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Baseline determination,pollution source and ecological risk of heavy metals in surface sediments of the Amu Darya Basin,Central Asia

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Journal of Geographical Sciences 2022年第11期32卷 2349-2364页

作者： ZHAN Shuie WU jinglu jin miao ZHANG Hongliang State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyCASNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

Central Asia(CA)is one of the most fragile regions worldwide owing to arid climate and accumulated human activities,and is a global hotspot due to gradually deteriorating ecological *** Amu Darya Basin(ADB),as the most economically and demographically important region in CA,is of particular *** determine the concentration,source and pollution status of heavy metals(HMs)in surface sediments of the ADB,154samples were collected and analyzed for metals across the *** and cluster analysis,and positive matrix factorization model were implemented to understand metals’association and apportion their possible *** frequency distribution and normalization methods were used to determine the geochemical baseline values(GBVs).Then,various pollution indices and ecological risk index were employed to characterize and evaluate the pollution levels and associated risks based on the *** indicated that the mean concentrations of HMs showed the following descending order in the surface sediments of ADB:Zn>Cr>Ni>Cu>Pb>Co>*** spatial distribution maps showed that Cr,Ni,and Cu had relatively high enrichment in the irrigated agricultural area;high abundances of Zn,Pb,and Cd were mainly found in the urban *** source factors were identified for these metals,namely natural sources,industrial discharge,agricultural activities,and mixed source of traffic and mining activities,accounting for 33.5%,11.4%,34.2%,and 20.9%of the total contribution,*** GBVs of Cd,Zn,Pb,Cu,Ni,Cr,and Co in the ADB were 0.27,58.9,14.6,20.3,25.8,53.4,and 9.80 mg/kg,respectively,which were similar to the regional background values obtained from lake sediments in the *** general,the assessment results revealed that surface sediments of the ADB were moderately polluted and low ecological risk by HMs.

关键词： heavy metal spatial distribution source identification geochemical baseline value risk assessment Amu Darya Basin

Shakedown Criterion Employing Actual Residual Stress Field and Its Application in Numerical Shakedown Analysis

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 919-927页

作者： ZOU Zongyuan GUO Baofeng LI Yinxiao jin miao ZHAO Shiyan Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Chinese 91315 People's Liberation Army Troops

Construction of the static admissible residual stress field and searching the optimal field are key tasks in the shakedown analysis methods applying the static theorem. These methods always meet dimension obstacles when dealing with complex problems. In this paper, a novel shakedown criterion is proposed employing actual residual stress field based on the static shakedown theorem. The actual residual stress field used here is produced under a specified load path, which is a sequence of proportional loading and unloading from zero to all the vertices of the given load domain. This ensures that the shakedown behavior in the whole load domain can be determined based on the theorem proposed by K6nig. The shakedown criterion is then implemented in numerical shakedown analysis, The actual residual stress fields are calculated by incremental finite element elastic-plastic analysis technique for finite deformation under the specified load path with different load levels. The shakedown behavior and the shakedown limit load are determined according to the proposed criterion. The validation of the criterion is performed by a benchmark shakedown example, which is a square plate with a central hole under biaxial loading. The results are consistent with existing results in the literatures and are validated by full cyclic elastic-plastic finite element analysis. The numerical shakedown analysis applying the proposed criterion avoids processing dimension obstacles and performing full cyclic elastic-plastic analysis under arbitrary load paths which should be accounted for appearing. The effect of material model and geometric changes on shakedown behavior can he considered conveniently.

关键词： elastoplastic finite element shakedown criterion specified load path actual residual stress field

Formation Mechanism of Inclusion Defects in Large Forged Pieces

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Journal of Iron and Steel Research International 2016年第6期23卷 531-538页

作者： Rong-sheng QI miao jin Xin-gang LIU Bao-feng GUO Key Laboratory of Advanced Forging and Stamping Technology and Science of Ministry of Education Yanshan University

Nonmetallic inclusions mixed into large forged metal objects destroy the continuity in the metal and affect the quality of the forged *** on how inclusions affect the plastic deformation of a matrix shows the significance of the formation mechanism of inclusion *** upset forging,the nonlinear finite element model was shown to be appropriate for the ingot hot-forging process by comparing the results with experiments involving plastic and hard inclusions inserted into the forged *** high-temperature stress-strain curves of MnS plastic inclusions were obtained *** results show how,during upsetting,the morphology of MnS plastic inclusions varies from spherical to ellipsoidal,until finally becoming flat in *** larger the inclusion is,the larger the degree of deformation of the inclusion is,and large inclusions enhance the risk of the final product failing to pass inspection for inclusion *** significantly concentrates in the matrix near a hard *** the hard inclusion reaches a certain size,conical fractures form on both sides of the *** pass inclusion-flaw inspection and close hole defects to the extent possible,the flat-anvil upsetting is ***,the inclusiondeformation state obtained by finite element simulation is verified experimentally.

关键词： inclusion inspection anvil spherical destroy continuity forging finally verified ingot

Promotion of hexadecyltrimethyleamine bromide to the damage of Alexandrium ***3 by cupric glutamate

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Journal of Environmental Sciences 2006年第6期18卷 1152-1156页

作者： LI Hao miao jin-lai CUI Feng-xia LI Guang-you Key Laboratory of Marine Biological Active Substances SOA Qingdao 266061 China Institute of Radiation Medicine Academy of Military Medical Sciences Beijing 100850 China College of Food Science and Technology Ocean University of China Qingdao 266003 China

The effect of hexadecyltrimethyleamine bromide （HDTMAB） on the removal of A lexandrium sp. LC3 under cupric glutamate stress was investigated. Toxic effect of cupric glutamate on A lexandrium sp. LC3 was significantly promoted in the presence of HDTMAB, especially at 3.0 cmc of HDTMAB. It was found that the sulfhydryl group content of the cell decreased, while the malonaldehyde content and membrane permeability increased when A lexandrium sp. LC3 was treated with HDTMAB and cupric glutamate complex, compared with cupric glutamate alone. The data suggest that HDTMAB might stimulate the damage of A lexandrium sp. LC3 by enhancing the membrane permeability.

关键词： HDTMAB cupric glutamate A lexandrium sp. LC3 cell membrane permeability

Human gut microbiota： the links with dementia development

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Protein & Cell 2017年第2期8卷 90-102页

作者： Rashad Alkasir jing Li Xudong Li miao jin Baoli Zhu Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China China-Japan Friendship Hospital Beijing 100029 China Collaborative Innovation Centre for Diagnosis and Treatment of Infectious Diseases The First Attainted Hospital College of Medicine Zhejiang University Hangzhou 310058 China

Dementia is a comprehensive category of brain diseases that is great enough to affect a person＇s daily functioning. The most common type of dementia is Alzheimer＇s disease, which makes most of cases. New researches indicate that gastrointestinal tract microbiota are directly linked to dementia pathogenesis through triggering metabolic diseases and low-grade inflammation progress. A novel strategy is proposed for the management of these disorders and as an adjuvant for psychiatric treatment of dementia and other related diseases through modulation of the microbiota （e.g. with the use of probiotics）.

关键词： dementia alzheimer's disease gut microbiota inflammation probiotics

Flow Stress Behaviors and Microstructure Evolution of 300M High Strength Steel under Isothermal Compression

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Journal of Iron and Steel Research International 2014年第12期21卷 1116-1123页

作者： Rong-sheng QI Bao-feng GUO Xin-gang LIU miao jin Key Laboratory of Advanced Forging & Stamping Technology and Science(Yanshan University) Ministry of Education of China

The compressive deformation behaviors of 300M high strength steel were investigated over a wide range of temperatures （850- 1200 C） and strain rates （0. 001- 10 s^- 1 ） on a Gleeble-3800 thermo-mechanical simulator. The measured flow stress was modified by the corrections of the friction and the temperature compensations, which nicely reflect negative effects of the friction and temperature on the flow stress. The corrected stress-strain curves were the dynamic recrystallization type on the conditions of higher deformation temperature and lower strain rate. Flow stress increases with the increase of strain rate at the same deformation temperature and strain. By contrast, flow stress decreases with the increase of temperature at the same strain rate and strain. Dependence of the peak stress on temperature and strain rate for 300M steel is described by means of the conventional hyperbolic sine equation. By re gression analysis, the activation energy （Q） in the whole range of deformation temperature is determined to be 367. 562 kJ/mol. The effects of the temperature and the strain rate on mierostructural evolution are obvious. With the increase of the deformation temperature and the decrease of the strain rate, the original austenite grain sizes of 300M steel increase. At the same time, the corrected flow stress curves more accurately determine the evolution of the microstrueture.

关键词： 300M high strength steel flow stress curve correction microstructural evolution

Rapid,Energy-saving Bioinspired Soft Switching Valve Embedded in Snapping Membrane Actuator

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Journal of Bionic Engineering 2023年第1期20卷 225-236页

作者： Fangzhou Zhao Yingjie Wang Sijia Liu miao jin Luquan Ren Lei Ren Chunbao Liu School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130022China Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun130022China School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK

In nature,organisms widely use the interaction of muscle contraction and biological pipelines to form an efficient fluid control ***,a pneumatically powered,Bioinspired Soft Switching valve(BSS valve)with short response time and low-energy consumption is *** BSS valve is composed of flexible walls,a flexible tube and symmetrically arranged Snapping Membrane actuator(SM actuator).It functions based on tube deformation throttling caused by instability of SM actuator *** realize rapid preparation of customized BSS valve,the modular manufacturing method suitable for different materials and structures based on 3D printing and mold forming was *** the membrane flip rate as indicators,the displacement transient response characteristics of three structures actuators were studied,The results proved that spherical and spherical cap membrane SM actuator achieved rapid displacement response under the low critical pressure ***,with critical buckling pressure and capacity utilization efficiency as indicators,we analyzed the characteristics of SM actuators with different radius and wall thickness to obtain reasonable structural parameters configuration of SM *** influence of radius and thickness on SM actuator is revealed,and theoretical model formulas were *** different configurations are presented.(1)Customized BSS valve structures can achieve sequential motion of flexible gripper.(2)BSS valve embedded in soft *** performance tests confirmed it has significant advantages in energy consumption,specific pressure,specific flow,high-frequency cycle load life,and valve can be integrated into the soft pump fluid system as a throttling unit,and provides an idea for fluid drive control integration.

关键词： Bioinspired.Soft robot BSS valve SM actuator

Experimental models for preclinical research in kidney disease

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Zoological Research 2024年第5期45卷 1161-1174页

作者： jin miao Huanhuan Zhu Junni Wang Jianghua Chen Fei Han Weiqiang Lin Kidney Disease Center First Affiliated HospitalZhejiang University School of MedicineInstitute of NephrologyZhejiang UniversityKey Laboratory of Kidney Disease Prevention and Control TechnologyZhejiang ProvinceZhejiang Clinical Research Center of Kidney and Urinary System DiseaseHangzhouZhejiang 310003China Department of Nephrology Center for Regeneration and Aging MedicineFourth Affiliated Hospital of School of Medicineand International School of MedicineInternational Institutes of MedicineZhejiang UniversityYiwuZhejiang 322000China

Acute kidney injury(AKI)and chronic kidney disease(CKD)are significant public health issues associated with a long-term increase in mortality risk,resulting from various etiologies including renal ischemia,sepsis,drug toxicity,and diabetes *** preclinical models have been developed to deepen our understanding of the pathophysiological mechanisms and therapeutic approaches for kidney *** these,rodent models have proven to be powerful tools in the discovery of novel therapeutics,while the development of kidney organoids has emerged as a promising advancement in the *** review provides a comprehensive analysis of the construction methodologies,underlying biological mechanisms,and recent therapeutic developments across different AKI and CKD ***,this review summarizes the advantages,limitations,and challenges inherent in these preclinical models,thereby contributing robust evidence to support the development of effective therapeutic strategies.

关键词： Acute kidney injury Chronic kidney disease Mouse models

Tau truncation in the pathogenesis of Alzheimer's disease:a narrative review

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Neural Regeneration Research 2024年第6期19卷 1221-1232页

作者： Dandan Chu Xingyue Yang jing Wang Yan Zhou jin-Hua Gu jin miao Feng Wu Fei Liu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsCoinnovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Department of Biochemistry and Molecular Biology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Clinical Pharmacy Affiliated Maternity and Child Health Care Hospital of Nantong UniversityNantong UniversityNantongJiangsu ProvinceChina Laboratory of Animal Center Nantong UniversityNantongJiangsu ProvinceChina Department of Neurochemistry Inge Grundke-Iqbal Research FloorNew York State Institute for Basic Research in Developmental DisabilitiesStaten IslandNYUSA

Alzheimer's disease is characterized by two major neuropathological hallmarks—the extracellularβ-amyloid plaques and intracellular neurofibrillary tangles consisting of aggregated and hyperphosphorylated Tau *** studies suggest that dysregulation of the microtubuleassociated protein Tau,especially specific proteolysis,could be a driving force for Alzheimer's disease *** physiologically promotes the assembly and stabilization of microtubules,whereas specific truncated fragments are sufficient to induce abnormal hyperphosphorylation and aggregate into toxic oligomers,resulting in them gaining prion-like *** addition,Tau truncations cause extensive impairments to neural and glial cell functions and animal cognition and behavior in a fragment-dependent *** review summarizes over 60 proteolytic cleavage sites and their corresponding truncated fragments,investigates the role of specific truncations in physiological and pathological states of Alzheimer's disease,and summarizes the latest applications of strategies targeting Tau fragments in the diagnosis and treatment of Alzheimer's disease.

关键词： Alzheimer's disease cleavage site diagnosis marker neurofibrillary tangles phosphorylation Tau Tau aggregation therapy truncation