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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2 & XU WeiSheng 2 1 college of Hydraulic and Environmental engineering,china Three Gorges university,Yichang 443002,china 2 college of hydropower engineering,xi’an university of technology,xi’an 710048,china 1. college of Hydraulic and Environmental engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

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(RSD2.2%).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

Role of biochar in raising blue carbon stock capacity of salt marshes

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Pedosphere 2024年第1期34卷 19-22页

作者： Yuzhou HUANG xi xiAO Ocean college Zhejiang UniversityZhoushan 316021China Key Laboratory of Marine Ecological Monitoring and Restoration Technologies of the Ministry of Natural Resources of china Shanghai 201306China Donghai Laboratory Zhoushan 316021China Ocean Academy Zhejiang UniversityZhoushan 316021China Key Laboratory of Watershed Non-point Source Pollution Control and Water Eco-security of Ministry of Water Resources College of Environmental and Resources SciencesZhejiang UniversityHangzhou 310058China

Salt marshes are an important blue carbon ecosystem, with surprisingly fast carbon accumulation rates that are 40 times higher than those of terrestrial forests. In recent decades, salt marshes have suffered great degradation and loss all over the world. The idea to enhance carbon stock in salt marshes(so-called blue carbon) using biochar (so-called black carbon) has recently been proposed. Although experiments and observations remain limited, significant enhancements in soil organic carbon and plant growth have been documented in most case studies. However, due to the limited number of observations and their relatively short time window ranging from months to less than one year, there still exists a knowledge gap regarding the process, mechanism, and effect of biochar in enhancing carbon stock in salt marshes. Future research is urgently needed in the following perspectives:1) exploring the relationship between carbon stock enhancement efficiency and biochar properties, 2) optimizing the physical and chemical properties of biochar to boost its efficiency, and 3)studying the in-situ responses of complex carbon pools to biochar addition, especially under tidal conditions and over a longer period of time.

关键词： soil stock char

Traditional Chinese Medicine Integrated Responsive Microneedles for Systemic Sclerosis Treatment

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Research 2024年第1期2023卷 139-147页

作者： xi Luan xiaoxuan Zhang Min Nie Yuanjin Zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of PharmacyClinical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

Traditional Chinese medicine,such as Tripterygium wilfordii and Paeonia lactiflora,has potential values in treating systemic sclerosis(SSc)and other autoimmune diseases,while their toxic side effect elimination and precise tropical drug delivery are still ***,we present multiple traditional Chinese medicine integrated photoresponsive black phosphorus(BP)microneedles(MNs)with the desired features for the SSc *** employing a template-assisted layer-by-layer curing method,such MNs with triptolide(TP)/paeoniflorin(Pae)needle tips and BP-hydrogel needle bottoms could be well *** combined administration of TP and Pae can not only provide anti-inflammatory,detoxification,and immunomodulatory effects to treat skin lesions in the early stage of SSc but also remarkably reduce the toxicity of single drug ***,the additive BPs possess good biocompatibility and near-infrared(NIR)responsiveness,imparting the MN photothermal-controlled drug release *** on these features,we have demonstrated that the traditional Chinese medicine integrated responsive MNs could effectively improve skin fibrosis and telangiectasia,reduce collagen deposition,and reduce epidermal thickness in the SSc mouse *** results indicated that the proposed Chinese medicine integrated responsive MNs had enormous potential in clinical therapy of SSc and other diseases.

关键词： needle precise template

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： Jin-xi Zhang Kai-Di Xu Qing-Guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this ***, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

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

B-cell lymphoma-2 phosphorylation at Ser70 site-related autophagy mediates puerarin-inhibited the apoptosis of MC3T3-E1 cells during osteoblastogenesis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 27-34页

作者： LI xi LIN xiangquan CHEN Dongdong LIU Hui the Third Clinical Medical college Fujian Medical University Department of Orthopedics Fuzhou Second HospitalFuzhou 350007China

OBJECTIVE:To explore the relationship between autophagy and apoptosis regulated by puerarin during ***:In this study,the effects of puerarin on the autophagic activity and apoptosis level of osteoblast precursors(MC3T3-E1 cells)was ***,the roles of puerarin on B-cell lymphoma-2(Bcl-2)phosphorylation at different sites in osteoblast precursors were *** effect of puerarin on the interaction between Bcl-2 and autophagy regulatory molecule or pro-apoptotic molecule was also investigated using Co-immunoprecipitation *** addition,the effect of puerarin on mitochondrial membrane potential of osteoblast precursors was also identified by mitochondrial membrane potential fluorescence probe ***:Our results showed that puerarin can promote the autophagic activity and apoptosis level of *** addition,puerarin promoted Bcl-2phosphorylation at Ser70 site,and the dissociation of Bcl-2-Beclin1 ***,puerarin could enhance the binding of Bcl-2-Bcl-2-Associated X(Bax)complex in MC3T3-E1 ***,puerarin increased the mitochondrial membrane potential of MC3T3-E1 ***:Therefore,puerarin promotes Beclin1into autophagy flux through Bcl-2 phosphorylation at Ser70,thereby enhancing autophagy of osteoblast precursors,which mediates its anti-apoptotic role during ***,the dissociation of Bcl-2-Beclin1 complex is conducive to the binding of Bcl-2-Bax complex,which resists the apoptosis of osteoblast precursors via the increased mitochondrial membrane potential.

关键词： puerarin osteoblasts autophagy apoptosis lymphoma B-cell

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On Depolymerization

CCS Chemistry 2024年第2期6卷 297-312页

作者： Bo Qin xi Zhang college of Chemistry and Chemical engineering Hunan UniversityChangsha 410082 Department of Chemistry Tsinghua UniversityBeijing 100084

Polymers have become an essential part of modern life and the global economy on account of their costeffectiveness and versatile ***,most postconsumer polymer wastes are unrecycled,leading to environmental pollution and resource ***,as an efficient chemical recycling approach,holds great promise in establishing a circular polymer *** this review,we attempt to highlight recent and significant advancements in depolymerization *** key research topics are discussed:(1)depolymerization of commodity polymers to produce reusable monomers and high-value chemicals;(2)depolymerization of intrinsically depolymerizable *** is anticipated that this review will reflect the present status and future trends of this rapidly evolving realm of depolymerization.

关键词： depolymerization chemical recycling sustainable polymers circular polymer economy catalysis dynamic covalent chemistry

Integrating host biological and ecological variables to predict probability of haemosporidian infection in raptors

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Avian Research 2024年第2期15卷 255-264页

作者： Kai Gao Xuemei Yang xi Huang Wenhong Deng Ministry of Education Key Laboratory for Biodiversity Science and Ecological engineering College of Life SciencesBeijing Normal UniversityBeijing100875China

Variations in host traits that influence their exposure and susceptibility may impact probability of vector-transmitted ***,identifying the predictors of infection probability is necessary to understand the risk of disease outbreaks during expanding environmental ***,we conducted a large survey based on microscopic examination and molecular analysis of haemosporidian parasite infection in raptors rescued at the Beijing Raptor Rescue *** these data with biological and ecological variables of the raptors,we determined predictors that affect the probability of haemosporidian infection using generalized linear mixed models and multimodel *** results showed that infection probability exhibited considerable variation across host species in raptors,and body mass,sex,and evolutionary history played relatively weaker roles in driving infection ***,activity pattern,age,geographic range size,migration distance,and nest type were important predictors of the probability of haemosporidian infection,and the role of each predictor differed in the three main haemosporidian genera(Plasmodium,Haemoproteus,and Leucocytozoon).This macro-ecological analysis will add to our understanding of host traits that influence the probability of avian haemosporidian infection and will help inform risk of emerging diseases.

关键词： Activity pattern Emerging infectious diseases Infection probability Interspecific variation Migratory exposure