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A review of the neurotransmitter system associated with cognitive function of the cerebellum in Parkinson's disease

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Neural Regeneration Research 2024年第2期19卷 324-330页

作者： xi chen Yuhu Zhang Department of Neurology Guangdong Neuroscience InstituteGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhouGuangdong ProvinceChina Shantou University Medical College ShantouGuangdong ProvinceChina

The dichotomized brain system is a concept that was generalized from the‘dual syndrome hypothesis’to explain the heterogeneity of cognitive impairment,in which anterior and posterior brain systems are independent but partially *** dopaminergic system acts on the anterior brain and is responsible for executive function,working memory,and *** contrast,the cholinergic system acts on the posterior brain and is responsible for semantic fluency and visuospatial *** from dopaminergic/cholinergic imaging or functional neuroimaging has shed significant insight relating to the involvement of the cerebellum in the cognitive process of patients with Parkinson’s *** research has reported evidence that the cerebellum receives both dopaminergic and cholinergic ***,whether these two neurotransmitter systems are associated with cognitive function has yet to be fully ***,the precise role of the cerebellum in patients with Parkinson’s disease and cognitive impairment remains ***,in this review,we summarize the cerebellar dopaminergic and cholinergic projections and their relationships with cognition,as reported by previous studies,and investigated the role of the cerebellum in patients with Parkinson’s disease and cognitive impairment,as determined by functional *** findings will help us to understand the role of the cerebellum in the mechanisms underlying cognitive impairment in Parkinson’s disease.

关键词： anterior brain system cerebellum cholinergic cognitive impairment dopaminergic dual syndrome hypothesis neuroimage neurotransmitter Parkinson’s disease posterior brain system therapeutic targets

Bio-screening and quantification of methyl paraben in vinegar and coconut juice separated by HPTLC

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Food Science and Human Wellness 2024年第3期13卷 1602-1607页

作者： Yisheng chen xingjun xi College of Food Science and Engineering Shanxi Agricultural UniversityTaigu 030801China Insitute of Food Nutrition and Safety Shanxi Agricultural UniversityTaiyuan 030031China Institute of Agricultural Food Standardization China National Institute of StandardizationBeijing 100191China

As a widely used food preservative,methyl paraben was experimentally evidenced with serious hormonelike adverse ***,a high performance thin-layer chromatography platformed bioluminescent bioautography and image analysis for the selective quantification and confirmation of methyl paraben was proposed and validated in vinegar and coconut ***,the detectability of the bioautography to the analyte on different layer materials was estimated,revealing that normal silica gel was the best *** that,the liquid of sample extract and working solution were separated to overcome the background noises due to co-extracted *** separation result was then coupled to the optimized bioautography,enabling instant and straightforward screening of the targeted *** accurate quantification,bioluninescent inhibition pattern caused by the analyte was processed by image analysis,giving useful sensitivity(LOD>16 mg/kg),precision(RSD10.1%)and accuracy(spike-recovery rate 76.9%-112.2%).Finally,the suspected result was confirmed by determining its MS fingerprint,further strengthening the reliability of screening.

关键词： High performance thin-layer chromatography Bio-screening Bioluminescence Image analysis Methyl paraben

An extended numerical model of the first exothermic peak for three dimensional printed cement-based materials

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 80-88页

作者： Wei JIANG Wenqian LI xi chen School of Materials Science and Engineering Tongji UniversityShanghai 200092China School of Civil Engineering Tongji UniversityShanghai 200092China

The first exothermic peak of cement-based material occurs a few minutes after mixing,and the properties of three dimensional(3D)printed concrete,such as setting time,are very sensitive to *** this background,based on the classical Park cement exothermic model of hydration,we propose and construct a numerical model of the first exothermic peak,taking into account the proportions of C_(3)S,C_(3)A and quicklime in *** calculated parameters are calibrated by means of relevant published exothermic test *** is found that this developed model offers a good simulation of the first exothermic peak of hydration for C_(3)S and C_(3)A proportions from 0 to 100% of cement clinker and reflects the effect of quicklime content at 8%-10%.The unique value of this research is provision of an important computational tool for applications that are sensitive to the first exothermic peak of hydration,such as 3D printing.

关键词： 3D printed cement-based materials cement hydration the first exothermic peak liquid quick-setting agent numerical model

A Systematic Analysis of Early Life Exposure to the Chinese Famine(1959-1961)and the Health of Older Adults-China,2008-2023

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China CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： Chi Shen xi chen School of Public Policy and Administration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Department of Health Policy and Management Yale School of Public HealthNew HavenCTU.S Department of Economics Yale UniversityNew HavenCTU.S

What is already known about this topic?There is mounting evidence indicating that the aging process initiates during early life stages,with in utero the individual’s environment playing a significant ***,it is crucial to comprehend the enduring effects of early life circumstances on health in old *** is added by this report?In this study,we conducted a meta-analysis to examine the effects of the Chinese Famine(1959–1961)on the health of older *** also explored potential mechanisms underlying these *** are the implications for public health practice?The complex interplay between early life circumstances,multiple health-related sectors,and healthy aging necessitates a comprehensive life-course approach and strategic interventions to enhance public health in an aging society.

关键词： life aging mount

Parameter Estimation of Sub-/Super-synchronous Oscillation Based on Interpolated All-phase Fast Fourier Transform with Optimized Window Function

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1031-1041页

作者： Bo Sun xi Wu xi chen Zixiao Zou Qiang Li Bixing Ren School of Electrical Engineering Southeast UniversityNanjingChina State Grid Jiangsu Electric Power Company Limited Research Institute NanjingChina

In recent years,with increasing amounts of renew-able energy sources connecting to power grids,sub-/super-syn-chronous oscillations(SSOs)occurred more *** to the time-variant nature of SsO magnitudes and frequencies,as well as the mutual interferences among SsO modes with close frequencies,the accurate parameter estimation of SsO has be-come a particularly challenging *** solve this issue,this paper proposes an improved spectrum analysis method by im-proving the window function and a spectrum correction method to achieve higher ***,by aiming at the sidelobe characteristics of the window function as evaluation criteria,a combined cosine function is optimized using a genetic algorithm(GA).Furthermore,the obtained window function is self-con-volved to extend its excellent characteristics,which have better performance in reducing mutual interference from other SSO ***,a new form of interpolated all-phase fast Fourier transform(IpApFFT)using the optimized window func-tion is proposed to estimate the parameters of *** meth-od allows for phase-unbiased estimation while maintaining algo-rithmic simplicity and *** performance of the pro-posed method is demonstrated under various conditions,com-pared with other estimation *** results vali-date the effectiveness and superiority of the proposed method.

关键词： Sub-/Super-synchronous oscillation(SSO) window function parameter estimation interpolated all-phase fast Fourier transform(ApFFT)

A Microenvironment, Rather than Chemical, Initiates the Cardiomyogenic Differentiation of Marrow Stromal Cells

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Wuhan University Journal of Natural Sciences 2004年第4期9卷 513-521页

作者： LIU Wei-xin 1,2 , SONG Jian 1 , WAN Yu 1, PAN Guo-dong 1 , LIU Yu 1 , chenG Bang-chang 2 ,chen xi-chang 1 1. School of Medicine, Wuhan University, Wuhan 430071, Hubei, China 2. Renmin Hospital, Wuhan University, Wuhan 430060, Hubei, China Sch. of Medicine Wuhan Univ. Wuhan 430071 China Renmin Hospital Wuhan Univ. Wuhan 430060 China

To investigate the potential of cardiomyogenic differentiation of rat bone marrow stromal cells (MSCs), they were exposed to 5-azacytidine tretments (single/repeat) at varying concentrations (3, 5, 10 μmol/L) and the fates of the cells were analyzed by immunocytochemistry, Western blot and the reporter gene of enhanced cyan fluorescent protein (ECFP) under the control of ventricular myosin light chain 2 (MLC2v) promoter. MSCs were also cocultured with cardiomyocytes for periods up to 16 days, the expression of cardiac myosin heavy chain (MHC) and troponin I (Tn I) proteins was analyzed. After the induction with 5-azacytidine, neither spontaneously beating cells nor myotubes were found; MHC and Tn I proteins were also undetectable and no ECFP-positive MSCs were detected. But when cocultured with cardiomyocytes, spontaneously contracting MSCs were observed and cardiac specific proteins could be detected. The results proved that the novel effects of 5-azacytidine on the cardiomyogenic differentiation of MSCs should be questioned and a direct intercellular communication with cardiomyocytes is necessary for MSCs to differentiate into cardiomyocytes. Key words cardiomyocyte - cell differentiation - stem cell CLC number Q 813.5 - R 542.2+2 Foundation item: Supported by the Natural Science Foundation of Hubei Province (2002AB00150)Biography: LIU Wei-xin (1976-), male, Ph. D candidate, research direction: stem cell and cellular biology.

关键词： cardiomyocyte cell differentiation stem cell

A hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction

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Control Theory and Technology 2024年第3期22卷 394-405页

作者： Chuanxiang Gao xinyi Wang xi chen Ben M.chen Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongShatinNTChina

Unmanned aerial vehicles(UAVs)are emerging as a powerful tool for inspections and repair works in large-scale and unstructured 3D infrastructures,but current approaches take a long time to cover the entire *** using UAVs for inspections and repair works puts forward a requirement of improving time efficiency in large-scale and cluster *** paper presents a hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction to balance the workload and reduce the overall task completion *** proposed framework consists of two stages,the exploration stage and the exploitation stage,resolving the task in a sequential *** the exploration stage,the density map is developed to update global and local information for dynamic load-balanced area partition based on reconstructability and relative positions of UAVs,and the Voronoi-based planner is used to enable the UAVs to reach their best *** obtaining the global map,viewpoints are generated and divided while taking into account the battery capacity of each ***,a shortest path planning method is used to minimize the total traveling cost of these viewpoints for obtaining a high-quality *** experiments are conducted in both a simulated and real environment to show the time efficiency,robustness,and effectiveness of the proposed ***,the whole system is implemented in real applications.

关键词： Multi-UAV Coverage path planning Infrastructure inspection and reconstruction

Chinese Economic Structure and SDA Model

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Systems Science and Systems Engineering 2000年第2期10卷 142-148页

作者： chen xi\|kang 1,\ GUO Ju\|e 2 1. Academy of Machemation and Systems Science, Chinese Academy of Science Beijing 100080, China 2. Shaanxi Institute of Finance and Economics, xi′an 710061, China

With the rapid economic growth, Chinese economic structure has greatly changed. In this paper we propose a new structural decomposition analysis (SDA) model and use it to analyze the Chinese structure change from 1981 to 1995 on the basis of input\|output tables of China with 18 sectors at current price and at constant price, constructed by us.

关键词： economic structure SDA model input\|output table

A theoretical model for impact protection of flexible polymer material

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 217-226页

作者： Huifeng xi Hui Pan Song chen Heng xiao MOE Key Lab of Disaster Forecast and Control in Engineering School of Machanics and Construction EngineeringJinan UniversityGuangzhou 510632China Doctor Workstation of Xuwen County Guangdong Hydropower Energy Co. Ltd.Xuwen 524100China

The relationship between the protective performance of flexible polymer material and material parameters(elasticmodulus,viscosity coefficient)is explored,an impact collision motion equation between two bodies is establishedfrom the viscoelastic material constitutive,and the relationship between the kinematic response and the materialparameters is *** on the Kelvin constitutive model,a theoretical model for impact between the pro-tective body and the protected body is established,then the dynamic response is *** feasibility of themodel was verified by drop hammer experiment,and the material parameters(elastic modulus,viscosity coeffi-cient)were obtained by *** model is discretized and the relationship between local impact response andmaterial parameters is *** discussion results on the relationship between the impact response and theprotective material performance indicate that adjusting the elastic modulus,viscosity coefficient,and thicknessof the protective material can effectively improve protective effect.

关键词： Flexible polymer material Viscoelastic material Kelvin modelDynamic response Elastic modulus and viscosity coefficient