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Assessing benthic habitat quality using biotic indices in the Laizhou Bay, China

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Acta Oceanologica Sinica 2020年第2期39卷 49-58页

作者： Li Wang Xianxiang Luo Jianqiang Yang Juan Zhang Yuqing Fan jiayu shen Key Laboratory of Marine Environment and Ecology Ocean University of ChinaQingdao 266100China North China Sea Branch of Ministry of Natural Resources Qingdao 266061China Shandong Marine Resources and Environment Research Institute Yantai 264006China

As an important part of the Bohai economic rim,the Laizhou Bay has been stressed by serious eco-environmental problems in recent *** this study,the Shannon-Wiener index(H′),AZTI’s marine biotic index(AMBI)and the multivariate AMBI(M-AMBI)were used to assess the ecological quality status(EQS)of the Laizhou Bay according to macrobenthos data collected annually in August 2011–*** results showed that the overall benthic habitat quality in the Laizhou Bay was assessed as“Good”.However,25%of the samples were classified as“Moderate”,“Bad”or“Poor”status under degraded *** group III(EGIII)species which had a certain tolerance to environmental disturbances had a higher proportion in each station,and most of them had appeared the pollution indicator species Capitella *** indicated that the benthic habitat in the Laizhou Bay had been disturbed and polluted to some *** comparison of the three indices evaluation result and the RDA analysis showed that the H′and M-AMBI were more suitable when the relative abundance of the single species was high and the macrobenthic community was significantly imbalanced;when the relative abundance of opportunistic species(EGIV and EGV)was high,the AMBI and M-AMBI could reflected the EQS objectively;in an undisturbed and polluted environment,all the three indices could indicate the benthic habitats *** summary,the better correlation between the three indices and environmental factors showed that they were well responsive to the tendency of the benthic habitats quality in the Laizhou Bay.

关键词： Laizhou Bay macrobenthos ecological quality status Shannon-Wiener index AMBI M-AMBI

Benthic Habitat Quality Assessment Based on Biological Indices in Xiaoqing River Estuary and Its Adjacent Sea of Laizhou Bay,China

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Journal of Ocean University of China 2017年第3期16卷 537-546页

作者： LUO Xianxiang LIN Song YANG Jianqiang shen jiayu FAN Yuqing ZHANG Longjun Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao 266100 P. R. China North China Sea Branch of the State Oceanic Administration Qingdao 266033 P. R. China

Based on the macrofauna data(2008-2011) in Xiaoqing River estuary and its adjacent sea, Laizhou Bay of Bohai Sea, China, the AZTI Marine Biotic Index(AMBI) and Multivariate AMBI(M-AMBI) were used for benthic habitat quality(BHQ) assessment. Results showed that BHQ presented an obvious trend of improvement along the direction of stream channel and river mouth, and in the coastal areas. AMBI and M-AMBI were significantly related to environmental pressure gradient data. Therefore, the two indices can well indicate BHQ in the studied area. However, there were significant differences between results of the two indices. In the cases of low taxa number and high abundance of single species, AMBI might overestimate BHQ. We thus adjusted its thresholds to solve this problem. And M-AMBI might overestimate BHQ when benthic assemblage was dominated by the opportunistic species. Then we could raise the weight of AMBI in the calculation of M-AMBI to handle the problem.

关键词： Xiaoqing River estuary benthic habitat quality (BHQ) AMBI M-AMBI environmental parameters

Near-Field Beam Training for Holographic MIMO Communications: Typical Methods, Challenges and Future Directions

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ZTE Communications 2024年第1期22卷 41-52页

作者： shen jiayu YANG Jun ZHU Chen DENG Zhiji HUANG Chongwen Zhejiang University Hangzhou 310058China ZTE Corporation Shenzhen 518055China Polytechnic Institute Zhejiang UniversityHangzhou 310015China Zhejiang Dahua Technology Co. Ltd.Hangzhou 310053China

Holographic multiple-input multiple-output(HMIMO)has become an emerging technology for achieving ultra-high frequency spectral efficiency and spatial resolution in future wireless *** increasing antenna aperture leads to a more significant characterization of the spherical wavefront in near-field communications in HMIMO *** training as a key technique for wireless communication is worth exploring in this near-field *** with the widely researched far-field beam training,the increased dimensionality of the search space for near-field beam training poses a challenge to the complexity and accuracy of the proposed *** this paper,we introduce several typical near-field beam training methods:exhaustive beam training,hierarchical beam training,and multi-beam training that includes equal interval multi-beam training and hash multi-beam *** performances of these methods are compared through simulation analysis,and their effectiveness is verified on the hardware testbed as ***,we provide application scenarios,research challenges,and potential future research directions for near-field beam training.

关键词： holographic multiple-input multiple-output(HMIMO) beam training near-field equal interval multi-beam(EIMB)training hash multi-beam(HMB)training

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Research on the Transmutation of Chinese Loanwords-Based on Modern Chinese Dictionary(7th Edition)

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Sino-US English Teaching 2022年第8期19卷 277-282页

作者： FU Yi shen jiayu Zhejiang University of Finance and Economics HangzhouChina

Vocabulary plays an irreplaceable role in a *** an important carrier to record foreign cultures in vocabulary,loanwords are widely used in all aspects of *** Chinese Dictionary includes loanwords from a variety of languages from the perspective of universal *** paper takes the loanwords in Modern Chinese Dictionary(7th Edition)as the closed corpus,and analyzes the etymology,structure,word length,and other aspects while making blanket statistics on the *** representative words are investigated by word frequency and described from multiple perspectives.

关键词： loanwords Modern Chinese Dictionary word frequency statistics

Super-resolution fluorescence-assisted diffraction computational tomography reveals the threedimensional landscape of the cellular organelle interactome

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Light(Science & Applications) 2020年第1期9卷 1889-1903页

作者： Dashan Dong Xiaoshuai Huang Liuju Li Heng Mao Yanquan Mo Guangyi Zhang Zhe Zhang jiayu shen Wei Liu Zeming Wu Guanghui Liu Yanmei Liu Hong Yang Qihuang Gong Kebin Shi Liangyi Chen State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuanShanxi 030006China State Key Laboratory of Membrane Biology Beijing Key Laboratory of Cardiometabolic Molecular MedicineInstitute of Molecular MedicinePeking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China School of Software and Microelectronics Peking UniversityBeijing 100871China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China National Laboratory of Biomacromolecules Chinese Academy of Sciences Center for Excellence in BiomacromoleculesInstitute of BiophysicsBeijing 100101China Institute for Brain Research and Rehabilitation(IBRR) Guangdong Key Laboratory of Mental Health and Cognitive ScienceSouth China Normal UniversityGuangzhouChina Collaborative Innovation Center of Quantum Matter Peking UniversityBeijing 100871China PKU-IDG/McGovern Institute for Brain Research Beijing 100871China

The emergence of super-resolution(SR)fluorescence microscopy has rejuvenated the search for new cellular ***,SR fluorescence microscopy achieves high contrast at the expense of a holistic view of the interacting partners and surrounding ***,we developed SR fluorescence-assisted diffraction computational tomography(SR-FACT),which combines label-free three-dimensional optical diffraction tomography(ODT)with two-dimensional fluorescence Hessian structured illumination *** ODT module is capable of resolving the mitochondria,lipid droplets,the nuclear membrane,chromosomes,the tubular endoplasmic reticulum,and *** dual-mode correlated live-cell imaging for a prolonged period of time,we observed novel subcellular structures named dark-vacuole bodies,the majority of which originate from densely populated perinuclear regions,and intensively interact with organelles such as the mitochondria and the nuclear membrane before ultimately collapsing into the plasma *** work demonstrates the unique capabilities of SR-FACT,which suggests its wide applicability in cell biology in general.

关键词： landscape illumination partner

突发公共卫生事件中政务短视频主题与用户行为的关联演化研究

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情报杂志 2023年第3期42卷 181-189页

作者：张敏沈嘉裕武汉大学信息资源研究中心武汉430072 武汉大学信息管理学院武汉430072

[研究目的]政务短视频如何精准地服务于用户需求已成为数字政务管理实践中的重点和难点。从主题与行为的关联演化的视角出发,对这一问题展开深入探究并提出针对性的意见和建议,能为政府制定适宜的政务短视频发布策略提供决策支持。[研... 详细信息

[研究目的]政务短视频如何精准地服务于用户需求已成为数字政务管理实践中的重点和难点。从主题与行为的关联演化的视角出发,对这一问题展开深入探究并提出针对性的意见和建议,能为政府制定适宜的政务短视频发布策略提供决策支持。[研究方法]设计网络爬虫程序抓取政务短视频数据,基于政务话语框架和BERTopic模型对政务短视频标题进行主题挖掘,并结合话题与用户行为数据进行关联分析。[研究结论]政务短视频运营方应基于舆情不同生命阶段的用户特征指定个性化的政务短视频主题发布策略,应加大观点框架的使用频度和使用力度。但在舆情爆发期,应特别重视和强化信息框架下的短视频发布。将框架理论引入政务短视频的主题挖掘研究,并基于短视频主题和用户行为的双重视角构建了突发公共卫生事件期间政务短视频的话语框架,为突发公共卫生事件中政务短视频运营管理提供了一种全新的发布策略。

关键词：网络舆情突发公共卫生事件政务短视频话语框架用户行为

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高锰酸钾灭活铜绿微囊藻及胞内毒素释放机制

同济大学学报（自然科学版） 2014年第5期42卷 721-729页

作者：高乃云沈嘉钰黎雷戎文磊同济大学污染控制与资源化研究国家重点实验室上海200092 无锡市自来水公司江苏无锡214031

采用高锰酸钾对微囊藻毒素MC-LR进行氧化试验,结果表明MC-LR氧化降解符合二级动力学模型,铜绿微囊藻细胞外代谢有机物（EOM）和细胞内代谢有机物（IOM）背景下,MC-LR降解速率常数分别为368.3 （mol·L-1）-1·s-1和400.2 （mol· L-1）-... 详细信息

采用高锰酸钾对微囊藻毒素MC-LR进行氧化试验,结果表明MC-LR氧化降解符合二级动力学模型,铜绿微囊藻细胞外代谢有机物（EOM）和细胞内代谢有机物（IOM）背景下,MC-LR降解速率常数分别为368.3 （mol·L-1）-1·s-1和400.2 （mol· L-1）-1·s-1.同时,采用高锰酸钾对铜绿微囊藻进行预氧化试验,研究不同氧化剂投加量、氧化时间对铜绿微囊藻活性、藻毒素MC-LR的释放的影响.结果表明,高锰酸钾对藻活性、细胞内MC-LR的释放均符合二级动力学模型.氧化过程中存在两个氧化剂暴露剂量临界点,细胞灭活临界点及毒素释放临界点.细胞灭活临界点之前氧化剂主要与EOM和藻细胞细胞壁上的分泌物反应,藻活性缓慢降低,细胞灭活临界点之后,氧化剂直接与细胞壁反应,导致藻细胞迅速丧失活性,同时藻活性下降速率常数由0.49～2.35 （mol·L-1）-1·s-1突变至5.00～19.38 （mol·L-1）-1·s-1.毒素释放临界点之前藻细胞基本保持完整,MC-LR释放不明显,毒素释放临界点处藻细胞发生明显破裂和溶解,细胞内MC-LR大量释放,同时,MC-LR释放速率常数在临界点前后由0.55～1.45 （mol·L-1）-1·s-1突变至0.96～14.45（mol·L-1）-1·s-1.3维荧光光谱（EEM）分析发现,当高锰酸钾暴露剂量达到细胞灭活临界点时,EOM中类腐殖质峰开始出现,暴露剂量达到毒素释放临界点时,类腐殖质峰显著增加,与藻细胞活性及胞内MC-LR释放规律类似.

关键词：高锰酸钾微囊藻毒素-LR 释放氧化动力学

有限合伙制私募股权投资基金中的随机性契约研究

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系统工程理论与实践 2020年第12期40卷 3124-3136页

作者：倪宣明沈佳瑜张俊超赵慧敏北京大学软件与微电子学院北京100871 中山大学管理学院广州510275

有限合伙制因其低运营成本、无双重税负和高激励等优势,广泛应用于私募股权投资基金等领域.本文研究了有限合伙制下私募股权投资基金的契约设计问题,探讨了随机性契约的作用.在委托代理理论框架下,设定比确定性契约更有效的随机性契约,... 详细信息

有限合伙制因其低运营成本、无双重税负和高激励等优势,广泛应用于私募股权投资基金等领域.本文研究了有限合伙制下私募股权投资基金的契约设计问题,探讨了随机性契约的作用.在委托代理理论框架下,设定比确定性契约更有效的随机性契约,需要施加较强的假设.我们发现由于普通合伙人是风险规避的,而且随机性契约又引入了额外的不确定性,因此一般情形下随机性契约不会占优于确定性契约.但是由于复杂形式的契约设计和监督成本较高,确定性契约通常选择简单可行的函数形式,使得契约设计转化为契约参数的选择问题,导致效率扭曲,此时契约参数随机化可纠正确定性契约中的效率扭曲,从而随机性契约成为更优选择.因此本文以线性契约为例,给出了在有限合伙制中,最优的随机性契约优于最优的确定性契约的参数条件,而且证明了此时随机性契约是对确定性契约的Pareto改进,且引致更高的努力水平.

关键词：私募股权投资基金有限合伙制随机性契约激励委托代理理论

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数字化转型下国有企业内部审计跟进探索

市场周刊 2023年第2期36卷 159-162页

作者：沈嘉钰南京审计大学江苏南京211815

在以科技创新为着力点的创新驱动战略下,国有企业纷纷探索并开展适合自身的数字化实践。同时,作为赋能国有企业聚焦创新驱动战略并助力高质量发展的内部审计也面临着履职路径全新探索、队伍建设再次强化等难点与堵点问题。文章综合分析... 详细信息

在以科技创新为着力点的创新驱动战略下,国有企业纷纷探索并开展适合自身的数字化实践。同时,作为赋能国有企业聚焦创新驱动战略并助力高质量发展的内部审计也面临着履职路径全新探索、队伍建设再次强化等难点与堵点问题。文章综合分析国有企业数字化转型和内部审计的发展概况,为与国有企业发展同频共振下的内部审计转型实践提供一定的思路和建议。

关键词：数据赋能内部审计数字化平台数字化敏感性