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Distribution of dissolved oxygen and causes of maximum concentration in the Bering Sea in July 2010

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Acta Oceanologica Sinica 2014年第6期33卷 20-27页

作者： sun Xiuwu LIN Cai CHEN Yong ZHANG Yuanbiao WANG jigang JI Weidong Third Institute of Oceanography State Oceanic Administration College of Ocean and Earth Sciences Xiamen University

According to data obtained in the Bering Sea during the 4th Chinese National Arctic Research Expedition, the distribution of dissolved oxygen （DO） was studied, causes of its maximum concentration were discussed, and the relationships between DO and other parameters, such as saliniW, temperature, and chlorophyll a were analyzed. The results showed DO concentration ranged from 0.53 to 12.05 mg/L in the Bering Sea basin. The upper waters contained high concentrations and the maximum occurred at the depth range from 20 to 50 m. The DO concentration decreased rapidly when the depth was deeper than 200 m and reached the minimum at the depth range from 500 to 1000 m, and then increased slowly with the depth increasing but still kept at a low level. On the shelf, the DO concentration ranged from 6.53 to 16.63 mg/L with a mean value of 10.75 mg/L, and showed a characteristic of decreasing from north to south. The DO concentration was higher in the area between the Bering Sea and Lawrence Island and was lower in the southeast and southwest of Lawrence Island at the latitude of 62°N. The formation of maximum DO concentration was concerned with phytoplankton photosynthesis and formation of the themocline. To the south of Sta. B07 in the Bering Sea basin, the oxygen produced by photosynthesis permeated to the deeper water and the themocline made it difficult to exchange vertically, and to the north of Sta. B07, the maximum DO concen- tration occurred above the themocline due to phytoplankton activities. On the shelf, the oxygen produced by phytoplankton photosynthesis gathered at the bottom of the thermocline and formed the DO maximum concentration. In the Bering Sea basin, the DO and salinity showed a weak negative correlation （r=0.40） when the salinity was lower than 33.1, a significant negative correlation （r=-0.92） when the salinity ranged from 33.1 to 33.7, and an irregular reversed parabola （r=0.95） when the salinity was greater than 33.7. Key words： Bering Sea, dissolved

关键词： Bering Sea dissolved oxygen maximum concentration stratification chlorophyll a

The measurement of electron beam transverse sizes by synchrotron radiation interferometry for HLS Ⅱ

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Nuclear Science and Techniques 2012年第4期23卷 193-198页

作者： TANG Leilei sun Baogen LU Ping WANG jigang XIAO Yunyun National Synchrotron Radiation Laboratory&School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230029China

In order to improve accuracy of electron beam transverse sizes measurement,the vertical and horizontal synchrotron radiation light interferometers have been designed to measure beam transverse sizes for the upgrade project of Hefei Light Source(HLS II).In this paper,the light intensity distributions of the interferogram are descussed,and parameters of the interferometers are *** interferograms are simulated under MATLAB. Taking integrations of two-dimensional interferogram intensity,normalized one-dimensional interference intensities distribution of the vertical and horizontal interferogram are *** two curves are fitted to compare the beam transverse sizes with the designed sizes,and this verifies the feasibility of this ***,several factors that affect the beam sizes measurement are discussed.

关键词：干涉测量横向尺寸 HLS 电子束同步辐射 MATLAB环境光强度分布尺寸测量

Impairment of the autophagy-lysosomal pathway in Alzheimer’s diseases: Pathogenic mechanisms and therapeutic potential

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Acta Pharmaceutica Sinica B 2022年第3期12卷 1019-1040页

作者： Wei Zhang Chengchao Xu Jichao sun Han-Ming Shen jigang Wang Chuanbin Yang Department of Geriatrics Shenzhen People’s Hospital(the Second Clinical Medical CollegeJinan Universitythe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020China Integrated Chinese and Western Medicine Postdoctoral Research Station Jinan UniversityGuangzhou 510632China Artemisinin Research Center Institute of Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Faculty of Health Sciences University of MacaoTaipaMacao 999078China Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical SciencesSouthern Medical UniversityGuangzhou 510515China

Alzheimer’s disease(AD),the most common neurodegenerative disorder,is characterized by memory loss and cognitive *** accumulation of misfolded protein aggregates including amyloid beta(Aβ)peptides and microtubule associated protein tau(MAPT/tau)in neuronal cells are hallmarks of *** far,the exact underlying mechanisms for the aetiologies of AD have not been fully understood and the effective treatment for AD is *** is an evolutionarily conserved cellular catabolic process by which damaged cellular organelles and protein aggregates are degraded via ***,there is accumulating evidence linking the impairment of the autophagy-lysosomal pathway with AD ***,the enhancement of autophagy to remove protein aggregates has been proposed as a promising therapeutic strategy for ***,we first summarize the recent genetic,pathological and experimental studies regarding the impairment of the autophagy-lysosomal pathway in *** then describe the interplay between the autophagy-lysosomal pathway and two pathological proteins,Aβand MAPT/tau,in ***,we discuss potential therapeutic strategies and small molecules that target the autophagy-lysosomal pathway for AD treatment both in animal models and in clinical ***,this article highlights the pivotal functions of the autophagy-lysosomal pathway in AD pathogenesis and potential druggable targets in the autophagy-lysosomal pathway for AD treatment.

关键词： Alzheimer’s disease(AD) Amyloid beta(Aβ)peptides MAPT/tau Autophagy-lysosomal pathway Autophagy enhancers Autophagy Mitophagy Neurodegenerative diseases

Conjugated polymerized bimetallic phthalocyanine based electrocatalyst with Fe-N_(4)/Co-N_(4) dual-sites synergistic effect for zinc-air battery

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Journal of Energy Chemistry 2023年第11期86卷 41-53,I0002页

作者： Shuaifeng Wang Zhongfang Li Wenjie Duan Peng sun jigang Wang Qiang Liu Lei Zhang Yanqiong Zhuang School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049ShandongChina

The bifunctional oxygen catalyst is essential for zinc-air batteries(ZABs).Here,an efficient bifunctional oxygen catalyst,PPcFeCo/3D-G,is obtained throughπ-πinteraction between the conjugated polymerized iron-cobalt phthalocyanine(PPcFeCo)with excellent thermal stability and three-dimensional graphene(3D-G).The bimetallic synergistic effect of PPcFeCo,verified by DFT(Density functional theory)calculation,andπ-πinteractions enhances the catalytic activity and durability of the PPcFeCo/*** electrochemical performance,the PPcFeCo/3D-G with a high electron transfer number(3.98,@0.768 V ***)has excellent half-wave potential(E_(1/2)=0.890 V ***)and exhibits outstanding reversibility(ΔE=0.700 V,ΔE=Ej=10-E_(1/2)).The liquid ZAB(LZAB)employed PPcFeCo/3D-G displays a high power density(222 m W cm^(-2)),a specific capacity(792 m A h g-1),and excellent durability(120 h).This work has guiding significance for the preparation of high-efficiency bifunctional catalysts.

关键词： Zn-airbattery Bifunctional oxygen catalysts Polymerized iron-cobalt phthalocyanine Bimetallic synergy π-πinteraction

Rise and Fall of Recent Chinese Coastal Resort Development:Case of Beihai Silver Beach, Guangxi, China

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Chinese Geographical Science 2012年第2期22卷 245-254页

作者： LIU Jun BAO jigang Department of Tourism Management South China Normal University Guangzhou 510631 China Center for Tourism Planning and Researeh Sun Yat-sen University Guangzhou 510275 China

Based upon a case study of Silver Beach coastal resort of Beihai, Guangxi Zhuang Autonomous Region, this article examines the rise and fall of Chinese coastal tourist resort development since the 1980s. It explores the causes for and responses to the decline of Chinese coastal resorts. The data were collected through in-depth interviews with twelve local key information providers, and secondary information sources such as government archives, survey reports, and resort plans. It was found that the rise and fall of Chinese coastal resorts in the last three decades is closely linked to the transitional reform from a central planned economy to a market economy. Three stages of coastal tourism development were identified in a sequence of rapid growth, decline and redevelopment. It was government financial funds and high local government involvement that promoted the rapid expansion of coastal resorts during the 1980s. However, coastal resort decline occurred when transitional reform was intensified and deflationary policy executed af- ter 1992. Institutional failure is found to be the main reason of Chinese coastal resorts decline since the mid-1990s. The government-dominated pattern could not be sustained and should be restructured in forthcoming coastal tourism de- velopment in China. Revival strategies should emphasize enhancing market-oriented reform in the declining resorts on both suoolv and demand sides.

关键词： coastal resort transitional decline Silver Beach Beihai

HLS bunch current measurement system

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 309-312页

作者： YANG YongLiang MA TianJi sun BaoGen LU Ping WANG jigang ZOU JunYing TANG LeiLei National Synchrotron Radiation Laboratory&School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230029China

Bunch current is an important parameter for studying the injection fill-pattern in the storage ring and the instability threshold of the bunch, and the bunch current monitor also is an indispensable tool for the top-up injection. A bunch current measurement (BCM) system has been developed to meet the needs of the upgrade project of Hefei Light Source (HLS). This paper presents the layout of the BCM system. The system based on a high-speed digital oscilloscope can be used to measure the bunch current and synchronous phase shift. To obtain the absolute value of bunch-by-bunch current, the calibration coefficient is measured and analyzed. Error analysis shows that the RMS of bunch current is less than 0.01 mA when bunch current is about 5 mA, which can meet project requirement.

关键词： bunch current fill-pattern synchronous phase shift Hefei Light Source (HLS)

Spatial Distribution of Integrated Impact Index of Mega-event——A Case Study of Expo '99 Kunming

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Chinese Geographical Science 2008年第3期18卷 214-223页

作者： DAI Guangquan BAO jigang School of Economics and Commerce South China University of Technology Guangzhou 510006 China Center for Tourism Planning ＆ Research SUN Yat-Sen University Guangzhou 510275 China

Taking the affinity between events and media as a conceptualization base, a total of 1032 related news re-ports of Expo '99 Kunming, gathered from the internet data bank of China INFOBANK from 1992 to 2003, are used as data sources. After classifying them with a communication research method-the content analysis, a data bank for SPSS is set up, and a mathematic model called the Integrated Impact Index of Expo '99 Kunming is constituted. With the model, the spatial distribution of the total integrated impacts of Expo '99 Kunming on the regions or cities with different regional scales is analysed quantitatively. The conclusions are: 1) the Expo '99 Kunming made obvious integrated impacts on the regions or cities of every scale, especially in the venue city and the region-Kunming City and Yunnan Province; 2) it had corresponding impacts on other provinces; 3) the spatial distribution of Integrated Impact Index had a disaggregation with both plane extension and spotted decentralization; and 4) there was a distance decay law in all three scales of regions (Kunming City, Yunnan Province and the whole China), which incarnated the spatial extension law of the integrated impact of a special mega-event.

关键词： Expo '99 Kunming Integrated Impact Index mega-event Yunnan Province

Temporal and spatial distribution characteristics of nutrients in Clarion-Clipperton Fracture Zone in the Pacific in 2017

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Acta Oceanologica Sinica 2022年第1期41卷 1-10页

作者： Baohong Chen Kaiwen Zhou Kang Wang jigang Wang Sumin Wang Xiuwu sun Jinmin Chen Cai Lin Hui Lin Third Institute of Oceanography Ministry of Natural ResourceXiamen 361005China Institute for Advanced Ocean Study Ocean University of ChinaQingdao 266003China

This research investigated eight stations in Clarion-Clipperton Fracture Zone(CCFZ)in the eastern tropical Pacific in 2017 to study the spatial distribution characteristics of nutrients and chlorophyll a(Chi a)concentration,and compared nutrient concentrations and molar ratios with those of other investigations 20 years ago in the same *** study found that dissolved inorganic nutrient(N,P and Si)concentrations were lowest in the upper layer,and increased from surface to some depths,then they decreased a little to the bottom.N was the limited nutrient factor for the growth of phytoplankton *** nutrient concentrations and molar ratios have no obvious changes in 2017 comparing those in 1998-2003,supplemented from the equatorial Pacific,nutrient concentrations in the study area were higher than those in seamounts in the North Pacific and Station ***,this study used Generalized Additive Models(GAMs)to infer the underlying bottom-up factors controlling phytoplankton abundance(Chi a concentration),showing that depth,salinity and PO^-P concentration were major factors controlling the growth of phytoplankton ***,this study can provide basic data and theoretical support for the development of polymetallic nodule area and its long-term impact assessment on the environment.

关键词： nutrients Chla GAMs CCFZ Pacific

原位生成砒霜的生物杂化体的制备及其体内外抗肝细胞癌评价

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中国现代应用药学 2024年第16期41卷 2167-2175页

作者：刘爱迪方威祥孙蒋李斌陈欣欣余凯玲叶婷娴朴寄纲李范珠浙江中医药大学药学院杭州310053

目的制备一种原位生成砒霜的生物杂化体(CeAs-Bac),并评价其体内外抗肝细胞癌效果。方法用静电吸附法和原位矿化法制备CeAs-Bac,并通过透射电镜、扫描电镜、马尔文粒径仪和X射线光电子能谱评价其外观形貌、电位及元素组成;采用透析袋法... 详细信息

目的制备一种原位生成砒霜的生物杂化体(CeAs-Bac),并评价其体内外抗肝细胞癌效果。方法用静电吸附法和原位矿化法制备CeAs-Bac,并通过透射电镜、扫描电镜、马尔文粒径仪和X射线光电子能谱评价其外观形貌、电位及元素组成;采用透析袋法和X射线光电子能谱考察CeAs-Bac的体外释放和释放前后砷(As)价态变化;以吲哚菁绿为荧光标记物考察HepG2摄取情况;采用MTT、活/死细胞染色法和Annexin V-FITC凋亡试剂盒分别考察CeAs-Bac的细胞毒性和凋亡情况;建立H22肝癌小鼠模型考察CeAs-Bac的体内抗肿瘤效果。结果成功制备了生物杂化体CeAs-Bac,透射电镜和扫描电镜结果表明砷铈(Ce)化合物紧密附着在希瓦氏菌表面,且修饰Ce和As后细菌表面电位由(−32.2±2.05)mV变为(−15.3±0.81)mV,As装载效率为60.6%;体外释放显示CeAs-Bac具有乳酸响应性释放的特点,且能在乳酸存在条件下生成砒霜;细胞实验结果证明CeAs-Bac对HepG2具有较高细胞毒性,并可诱导HepG2细胞凋亡;体内抗肿瘤结果显示CeAs-Bac可有效靶向肿瘤部位,抑制肿瘤生长,并促进肿瘤组织坏死。结论本研究成功制备了具有乳酸响应性释放及原位生成砒霜特点的生物杂化体CeAs-Bac,其能够有效降低砒霜在应用过程中的不良反应,实现肝细胞癌的安全有效治疗。

关键词：生物杂化体砒霜希瓦氏菌肝细胞癌乳酸