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Size structure of biomass and primary production of phytoplankton：environmental impact analysis in the Dongsha natural gas hydrate zone, northern South China Sea

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Acta Oceanologica Sinica 2018年第1期37卷 97-107页

作者： KANG Jianhua LIANG Qianyong WANG Jianjun LIN Yili HE Xuebao xia Zhen ZHENG Xinqing WANG yu Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China Guangzhou Marine Geological Survey China Geological Survey Guangzhou 510760 China

The size-fractionated biomass and primary production of phytoplankton, and the influence of environmental factors on it were studied in the Dongsha natural gas hydrate zone of the northern South China Sea in May *** nutrient, low chlorophyll a（Chl a） and primary productivity characteristics were found in these waters. The phenomena of subsurface Chl a maximum layers（SCMLs） and primary production maximum layers（SPMLs）were observed in the Dongsha waters. There were significant differences in the size-fractionated biomass and primary production that showed picophytoplankton〉nanophytoplankton〉microphytoplankton in terms of biomass and degree of contribution to production. Vertical biomass distribution indicated there were considerable differences among different phytoplankton within the euphotic zone（Zeu） in spring. For example,microphytoplankton was distributed evenly in the euphotic layer and nanophytoplankton was mainly distributed in the subsurface or in the middle of the euphotic layer, while picophytoplankton was mainly distributed in the middle or bottom of the euphotic layer. Smaller cell size and larger relative surface area allow picophytoplankton to benefit from nutrient competition and to hold a dominant position in the tropical oligotrophic waters of low latitudes. There was a positive correlation between size-fractionated biomass and temperature with pH and a negative correlation between size-fractionated biomass and silicate with phosphate. There was a positive correlation between size-fractionated primary production and temperature and a negative correlation between size-fractionated biomass and salinity with phosphate. Phosphate was an important factor influencing the size structure of phytoplankton. Meanwhile, irradiation and the euphotic layer were more important in regulating the vertical distribution of size-fractionated phytoplankton in the Dongsha natural gas hydrate zone.

关键词： phytoplankton biomass primary production size fractionation gas hydrate northern South China Sea

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Nickel Release Rate of Several Nickel-containing Stainless Steels for Jewelries

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Journal of Iron and Steel Research International 2015年第1期22卷 72-77页

作者： Jun-ping yuAN Wei LI Chang WANG Chun-yu MA Ling-xia CHEN De-dong CHEN Jewelry Institute of Guangzhou Panyu Polytechnic Department of Materials Science and Engineering Jinan University

Nickel-containing stainless steels have been widely applied in watch and jewelry production, and their re- sponses to the Nickel Directive become a universal concern in the industry. The nickel release rates and corrosion be- haviors of types 316L, 304, 303 and 201 stainless steels under the conditions of solid solution and mirror polishing were studied by artificial sweat soaking and electrochemical methods. The results show that the weekly nickel release rates in artificial sweat do not strictly correspond to the nickel contents, which present a descending order as 303 stainless steel of 2.06 μg/cm2 , 201 stainless steel of 1.51 μg/cm2 , 304 stainless steel of 0.08μg/cm2 and 316L stainless steel of 0.02 μg/cm2. Both the nickel release rates of type 303 and 201 stainless steels significantly exceed the threshold values regulated in EN1811 ： 2011 ; therefore, they should be avoided to be used as watch and jewelry materials owing to the risk of nickel sensitization. The nickel release rates of 316L and 304 stainless steels meet the requirements of the standard. Sulfide inclusions in stainless steel become the sources of pitting and exacerbate the damage of the passivation membrane, which is the significant cause to enhance the nickel release rates.

关键词： jewelry nickel-containing stainless steel nickel release rate nickel allergy

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超声分层应变技术评估急性病毒性心肌炎患者左心室收缩功能及与磁共振比较

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中国临床医学影像杂志 2024年第5期35卷 329-332,342页

作者：钟刚龙湘党敖琨谢娟娟史凤霞周琼李巧荣卓宇湖南省人民医院(湖南师范大学附属第一医院) 湖南长沙410005

目的:探讨超声分层应变技术评估急性病毒性心肌炎(AVMC)患者左室心肌收缩功能的价值。方法:前瞻性选取2020年1月—2023年2月在我院经临床诊断为AVMC且左室射血分数(LVEF)≥50%的患者37例作为病例组,另随机选取同期健康志愿者37例作为对... 详细信息

目的:探讨超声分层应变技术评估急性病毒性心肌炎(AVMC)患者左室心肌收缩功能的价值。方法:前瞻性选取2020年1月—2023年2月在我院经临床诊断为AVMC且左室射血分数(LVEF)≥50%的患者37例作为病例组,另随机选取同期健康志愿者37例作为对照组,比较两组常规超声心动图参数,并将病例组常规超声心动图参数与心脏磁共振(CMR)参数做对比分析;应用超声分层应变技术测量两组左室三层心肌收缩期整体纵向应变(GLS)及周向应变(GCS),分析组间差异及与CMR参数的相关性。结果:两组间常规超声心动图参数差异无统计学意义(P>0.05)。与CMR比较,常规超声心动图低估了病例组左室舒张末期容积(LVEDV)、左室收缩末期容积(LVESV)及每搏输出量(SV)(P<0.05)。病例组左室三层心肌GLS及GCS的绝对值较对照组均显著减低(P<0.001),与CMR参数视觉存在分数(VPS)均成负相关(P均<0.001)、LVEF均成正相关(P均<0.01)。结论:超声分层应变技术在早期识别AVMC患者左室心肌收缩功能损害中具有一定临床应用价值。

关键词：心肌炎心室功能,左超声检查,多普勒,彩色

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公路施工中软土路基的施工技术处理

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建筑与装饰 2024年第6期 103-105页

作者：杨红梅秦安县农村公路养护管理站甘肃天水 741600

自我国的第一个国家级干线公路网规划方案《国家干线公路网(试行方案)》(简称"国道网规划")试行以来,我国全面开展了公路施工建设工作,截至2022年末,全国已有535.48万km的公路里程.在开展公路施工时,会频繁遇到软土路基的问题,给施工团... 详细信息

自我国的第一个国家级干线公路网规划方案《国家干线公路网(试行方案)》(简称"国道网规划")试行以来,我国全面开展了公路施工建设工作,截至2022年末,全国已有535.48万km的公路里程.在开展公路施工时,会频繁遇到软土路基的问题,给施工团队带来了较大的困扰.本文分析了软土路基的主要特征,并从六个方面详细讨论了软土路基的主要施工技术,希望能够给软土路基的实际施工作业带来一点启发.

关键词：公路施工软土路基施工技术

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Dry cropland changes in China's Three Gorges Reservoir Region during the period 1990 to 2015

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Journal of Mountain Science 2020年第3期17卷 516-527页

作者： WANG Ming-feng TIAN Feng-xia HE Xiu-bin Raheel ANJUM BAO yu-hai Adrian LCOLLINS Key Laboratory of Mountain Surface Process and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Department of Tourism and Geography Tongren UniversityTongrenGuizhou Province554300China Abdul Wali Khan University MardanPakistan Sustainable Agriculture Sciences Department Rothamsted ResearchNorth WykeOkehamptonDevon EX202SBUK

Monitoring and analyzing changes in the extent of cultivated land may inform strategic decisions on issues of environmental and food *** dry cropland area of 12000 km^2in the Three Gorges Reservoir Region(TGRR)of China is essential for feeding the local population of^20 million,but is highly prone to soil erosion,leading to the delivery of excessive amounts of sediment and associated pollutants to the Three Gorges Reservoir(TGR),and causing serious eco-environmental *** this background,this paper used Landsat images and a digital elevation model to analyze the altitudinal distribution of,and dynamic changes in,the area of dry cropland during the period 1990 to *** results suggest that dry cropland was mainly distributed in the elevation range of 200-600 *** dry cropland area decreased from 12525.37 km^2to 11796.27 km^2during the 25-year study period,including a particularly significant decrease in the rate of decrease from 6.93 km^2/yr to 43.99 km^2/yr after *** largest decline in the dry cropland area occurred in the elevation range of 600-900 *** transformations between dry cropland and forest revealed the impact of the TGR operation on the extent of dry cropland.A total of 528.79 km^2of dry cropland with slopes>25°were converted to forest after 2000,whereas a total of 642 km^2of forest was converted to dry cropland during the study period,and these conversions mainly occurred between the elevation of 200–900 *** spatiotemporal changes in the dry cropland area are likely to raise new issues concerning food security in the TGRR.

关键词： Dry cropland Altitude Reservoir operation Three Gorges Reservoir Region Landuse change Soil erosion

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Efficient GSH delivery using PAMAM-GSH into MPP-induced PC12 cellular model for Parkinson’s disease

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Regenerative Biomaterials 2016年第5期3卷 299-307页

作者： Hong-Ji Sun Yan Wang Tong Hao Chang-Yong Wang Qi-yu Wang xiao-xia Jiang Department of Advanced Interdisciplinary Studies Institute of Basic Medical Sciences and Tissue Engineering Research CenterAcademy of Military Medical Sciences27 Taiping RoadHaidian DistrictBeijing 100850People’s Republic of China

Glutathione(GSH)depletion has been an important contributor to the dysfunction of dopamine ***-GSH(PAMAM-GSH)was synthesized and the delivery effect of GSH into PC12 cells was *** assessment for cytotoxicity and reactive oxygen species(ROS)as well as nitrite oxide(NO)and intracelluar superoxide dismutase(SOD)detection for antioxidative ability were ***,the antiapoptotic ability was analysed by assessing caspase-3,JNK1/2 and Erk1/2 *** data indicated that PAMAM-GSH is an effective agent to replenish GSH into PC12 ***-GSH developed its antioxidative and protective ability for 1-methyl-4-phenylpyridinium(MPP)-induced PC12 cells by reducing the intracellular levels of ROS and SOD activity as well as decreasing the release of ***,PAMAM-GSH could inhibit caspase-3 activation and might show its antiapoptotic ability to MPP-induced PC12 cells through JNK2/Erk1/2 *** summary,these studies suggest that PAMAM-GSH conjugate has an intrinsic ability to penetrate PC12 cells and deliver GSH into these cells which may provide a new strategy for clinical applications in the treatment of Parkinson’s disease.

关键词： polyamidoamine glutathione MPP PC12 cells Parkinson’s disease

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热力管道防腐保温施工技术及质量控制策略

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建筑与装饰 2024年第7期 164-166页

作者：李雪梅迁安市供热管理中心河北迁安 064400

热力管道是常见的市政设施之一,主要用于集中供暖服务,因供暖的服务对象较多,做好热力管道防腐保温也显得必要.本文以热力管道防腐保温施工技术及质量控制的不足为切入点,在此基础上,以迁安市甲工程为例,分别就热力管道防腐保温施工技... 详细信息

热力管道是常见的市政设施之一,主要用于集中供暖服务,因供暖的服务对象较多,做好热力管道防腐保温也显得必要.本文以热力管道防腐保温施工技术及质量控制的不足为切入点,在此基础上,以迁安市甲工程为例,分别就热力管道防腐保温施工技术以及质量控制策略进行论述,给出热力管道内外防腐、热力管道外层保温防护、质量控制精细化、提升质量控制针对性等内容,为后续热力管道防腐保温施工活动提供少许参考.

关键词：热力管道防腐保温施工内外防腐外层保温

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Highly sensitive and selective electrochemical immunosensors by substrate-enhanced electroless deposition of metal nanoparticles onto three-dimensional graphene@Ni foams

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Science Bulletin 2019年第17期64卷 1272-1279页

作者： Changrong Zhao xiaoli Li Shixia An Dongliang Zheng Shuaili Pei xiao Zheng yu Liu Qingqing Yao mei Yang Liming Dai Institute of Advanced Materials for Nano-Bio Applications School of Ophthalmology ■ Optometry Wenzhou Medical University Wenzhou 325027 China Department of Macromolecule Science and Engineering Case Western Reserve University Cleveland OH 44106 USA

In this study, we have for the first time preformed the facile substrate-enhanced electroless deposition(SEED) of metal nanoparticles onto monolithic graphene@Ni foams for construction of disposable three-dimensional(3 D) electrochemical immunosensors. Specifically, we firstly used the SEED method to deposit gold nanoparticles(AuNPs) onto the graphene@Ni foam for immobilization of antibody(Ab1). This is followed by a second step SEED deposition to produce silver nanoparticles(AgNPs) for electrochemical stripping detection. Using a-fetoprotein antigen(AFP) as a module analyte, the newly-developed sensor showed a wide linear response, ranging from 5.0 pg/mL to 5.0 ng/mL and a low detection limit down to 2.3 pg/mL. The newly-developed 3 D-immunosensor is sensitive, reliable,and easy to be fabricated, showing great potential for clinic applications.

关键词： Electrochemical immunosensor Substrate-enhanced electroless deposition Graphene Ni foam Metal nanoparticles a-Fetoprotein antigen

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Seismic energy dispersion compensation by multi-scale morphology

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Petroleum Science 2014年第3期11卷 376-384页

作者： yu Junqing Wang Runqiu Liu Taoran Zhang Zhenglong Wu Jian Jiang Yongyong Sun Lipeng xia Pei College of Geophysics and Information Engineering China University of Petroleum (Beijing) BGP Research & Development Center

Seismic energy decays while propagating subsurface, which may reduce the resolution of seismic data. This paper studies the method of seismic energy dispersion compensation which provides the basic principles for multi-scale morphology and the spectrum simulation method. These methods are applied in seismic energy compensation. First of all, the seismic data is decomposed into multiple scales and the effective frequency bandwidth is selectively broadened for some scales by using a spectrum simulation method. In this process, according to the amplitude spectrum of each scale, the best simulation range is selected to simulate the middle and low frequency components to ensure the authenticity of the simulation curve which is calculated by the median method, and the high frequency component is broadened. Finally, these scales are reconstructed with reasonable coefficients, and the compensated seismic data can be obtained. Examples are shown to illustrate the feasibility of the energy compensation method.

关键词： Seismic wave multi-scale morphology dispersion compensation high resolution median method spectrum simulation

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Interleukin 17A deficiency alleviates neuroinflammation and cognitive impairment in an experimental model of diabetic encephalopathy

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Neural Regeneration Research 2022年第12期17卷 2771-2777页

作者： xiao-xia Fang Fen-Fen Xu Zhan Liu Bei-Bei Cao Yi-Hua Qiu yu-Ping Peng Department of Physiology School of Medicineand Co-innovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina

Interleukin 17A(IL-17A)was previously shown to be a key pro-inflammatory factor in diabetes mellitus and associated ***,the role of IL-17A in diabetic encephalopathy remains poorly *** this study,we established a mouse model of diabetic encephalopathy that was deficient in IL-17A by crossing Il17a-/-mice with spontaneously diabetic Ins2^(Akita)(Akita)*** glucose levels and body weights were monitored from 2-32 weeks of *** mice were 32 weeks of age,behavioral tests were performed,including a novel object recognition test for assessing short-term memory and learning and a Morris water maze test for evaluating hippocampus-dependent spatial learning and ***-17A levels in the serum,cerebrospinal fluid,and hippocampus were detected with enzyme-linked immunosorbent assays and real-time quantitative polymerase chain ***,proteins related to cognitive dysfunction(amyloid precursor protein,β-amyloid cleavage enzyme 1,p-tau,and tau),apoptosis(caspase-3 and-9),inflammation(inducible nitric oxide synthase and cyclooxygenase 2),and occludin were detected by western blot ***-inflammatory cytokines including tumor necrosis factor-α,interleukin-1β,and interferon-γin serum and hippocampal tissues were measured by enzyme-linked immunosorbent *** activation and hippocampal neuronal apoptosis were detected by immunofluorescent *** with that in wild-type mice,mice with diabetic encephalopathy had higher IL-17A levels in the serum,cerebrospinal fluid,and hippocampus;downregulation of occludin expression;lower cognitive ability;greater loss of hippocampal neurons;increased microglial activation;and higher expression of inflammatory factors in the serum and ***-17A knockout attenuated the abovementioned changes in mice with diabetic *** findings suggest that IL-17A participates in the pathological process of diabetic ***,IL-17A deficiency reduces

关键词： Akita mice apoptosis cognitive impairment diabetic encephalopathy hippocampus interleukin 17A mice microglia neuroinflammation neuron targeted treatment

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