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中国通信:英文版 2023年第9期20卷 1-19页

作者： shanshan ma Bingpeng Zhou The School of Electronics and Communication Engineering Sun Yat-sen UniversityShenzhen 518107China

In this paper,joint location and velocity estimation(JLVE)of vehicular terminals for 6G integrated communication and sensing(ICAS)is studied.We aim to provide a unified performance analysis framework for ICAS-based JLVE,which is challenging due to random fading,multipath interference,and complexly coupled system models,and thus the impact of channel fading and multipath interference on JLVE performance is not fully understood.To address this challenge,we exploit structured information models of the JLVE problem to render tractable performance quantification.Firstly,an individual closedform Cramer-Rao lower bound for vehicular localization,velocity detection and channel estimation,respectively,is established for gaining insights into performance limits of ICAS-based JLVE.Secondly,the impact of system resource factors and fading environments,e.g.,system bandwidth,the number of subcarriers,carrier frequency,antenna array size,transmission distance,spatial channel correlation,channel covariance,the number of interference paths and noise power,on the JLVE performance is theoretically analyzed.The associated closed-form JLVE performance analysis can not only provide theoretical foundations for ICAS receiver design but also provide a perfor mance benchmark for various JLVE methods。

关键词： integrated sensing and communication vehicular state sensing Cramer-Rao lower bound

Comparative analysis of habitation behavioral patterns in spatial configuration of traditional houses in Anhui;Jiangsu;and Zhejiang provinces of China

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Frontiers of Architectural Research 2020年第1期9卷 54-66页

作者： Jie Ding shanshan ma School of Art Soochow UniversitySuzhouChina School of Art Anhui University of Finance&EconomicsBengbuChina School of Education Soochow UniversitySuzhouChina

This study investigated the categories of spatial characteristics of traditional houses in Anhui,Jiangsu,and Zhejiang provinces of China by applying syntactic theories and conducting a comparative analysis of their different layout configurations.Six houses in the three provinces were selected as measurement samples,and statistical analysis of their spatial variables was conducted through SPSS 22.Results showed that the correlation of depth and integration in the Zhejiang and Jiangsu samples are negative,whereas the samples in Anhui show no correlation.These results further indicated that spaces with high rates of utilization in Zhejiang and Jiangsu dwellings are located at low depths in the spatial configurations,whereas the samples from Anhui show opposite findings.Different housing spatial structures reflect various habitation behavioral patterns in this area.Zhejiang and Jiangsu residents interact more closely with outside spaces in their daily lives,whereas Anhui residents have very limited interaction with outside spaces,thereby reflecting two different modes of living behavior,namely,extroversion and introversion.

关键词： Traditional house Behavioral patterns Spatial configuration Anhui Jiangsu and Zhejiang provinces

数字平台自我优待的反垄断规制困境与优化进路

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法治研究 2024年第1期151卷 139-149页

作者：孙晋马姗姗武汉大学法学院

平台企业为开拓商业疆土,通过数据垄断、流量封锁等方式优待下游市场的自营业务,实现竞争优势乃至垄断地位的跨市场传导。从本质上来看,竞争优势的传导超越一定限度即可能构成滥用,不属于合法竞争的范围。平台自我优待由于符合杠杆理论... 详细信息

平台企业为开拓商业疆土,通过数据垄断、流量封锁等方式优待下游市场的自营业务,实现竞争优势乃至垄断地位的跨市场传导。从本质上来看,竞争优势的传导超越一定限度即可能构成滥用,不属于合法竞争的范围。平台自我优待由于符合杠杆理论对滥用行为的共同要求,应当被纳入反垄断法的规制范围。然而,鉴于我国当前该行为违法性统一认定标准缺失、反竞争效果难以判定、正当性抗辩理由滥用三项因素模糊了自我优待的反垄断规制边界,故在重塑分析框架基础上对其有针对性展开优化,明确平台自治的合理限度,以期为规制指明未来走向。

关键词：数字平台自我优待杠杆理论支配地位滥用反垄断规制

一种用于肼氧化-复合海水电解制氢的富吡啶氮碳纸

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Science China materials 2024年第3期67卷 752-761页

作者：马闪闪喻博夏宝玉游波 Key Laboratory of material Chemistry for Energy Conversion and Storage(Ministry of Education) Hubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

丰富的中性海水有望替代高纯淡水用于绿氢制备,然而基于过渡金属材料催化的直接海水电解会因析氯反应(ClER)引发严重的腐蚀问题并造成二次重金属污染,且析氧反应(OER)的动力学缓慢.本工作中,我们报道了一种稳定的富吡啶氮的碳纸(N-CP-80... 详细信息

丰富的中性海水有望替代高纯淡水用于绿氢制备,然而基于过渡金属材料催化的直接海水电解会因析氯反应(ClER)引发严重的腐蚀问题并造成二次重金属污染,且析氧反应(OER)的动力学缓慢.本工作中,我们报道了一种稳定的富吡啶氮的碳纸(N-CP-800),可以有效地催化肼氧化反应(HzOR),以取代中性海水中的OER用于节能制氢.结合电化学实验、原位衰减全反射-表面增强傅里叶变换红外光谱表征和密度泛函理论计算,我们发现:相较于吡咯氮和石墨氮,zig和arm构型的吡啶氮更有利于决速步(^(*)H+N_(2)H_(1))的质子脱附,以促进肼氧化反应.因此,N-CP-800在中性介质中进行HzOR时,仅需0.78 V(相对于可逆氢电势)便可达到10 ma cm^(-2),低于其OER/ClER竞争反应.当N-CP-800与非贵金属析氢催化剂CoP耦合进行HzOR-复合海水电解时,仅需1.56 V的电压即可达到10 ma cm^(-2),并能稳定运行200 h,优于Pt/C和RuO_(2)标准电极对催化的海水电解.

关键词： seawater electrolysis hydrazine oxidation hydrogen evolution nitrogen doping metal-free carbon

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金融科技平台垄断的公私协同治理

科技与法律（中英文） 2024年第4期 11-19页

作者：孙晋马姗姗武汉大学法学院武汉430072

金融科技平台垄断涉及数据互操作限制、扼杀式收购以及算法合谋等多种实践样态,其垄断行为既能在杠杆效应下提高竞争壁垒,也因其混业经营特性而容易诱发系统性风险。传统反垄断法公共规制路径依赖具有压制性与滞后性,难以应对复杂多变... 详细信息

金融科技平台垄断涉及数据互操作限制、扼杀式收购以及算法合谋等多种实践样态,其垄断行为既能在杠杆效应下提高竞争壁垒,也因其混业经营特性而容易诱发系统性风险。传统反垄断法公共规制路径依赖具有压制性与滞后性,难以应对复杂多变的金融科技平台垄断问题,需要为垄断治理提供全新的视角和方案,公私协同治理模式应运而生。在理论维度,协同治理所强调的灵活性、回应性能够满足风险社会下金融科技平台垄断的治理结构需求;在实践层面,金融科技平台内生的公私融合性以及根植于金融市场的合规传统,则为公私协同治理提供了现实基础。金融科技平台垄断问题在公私协同治理的具体实现上,需深化公私治理主体间的互信、促进治理规范的软硬协同,以及强化监管科技工具的共治目标嵌入。

关键词：金融科技平台垄断风险防范公共规制公私协同治理

vsx1 3' untranlated region-mediated translation difference at different developmental stages of goldfish embryos

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Journal of Genetics and Genomics 2009年第8期36卷 483-490页

作者： Jinhui Chen Ying Tong Shufang Zhao shanshan ma Chen Luo College of Life Science Hunan Normal University Changsha 410081 China College of Life Science Zhejiang University Hangzhou 310058 China

Visual system homeobox-1 （vsxl） is important in retinal progenitor proliferation, differentiation, and function maintenance of bipolar cells in vertebrates. Recent study in Xenopus laevis has shown that vsxl 3＇ untranslated region （3＇ UTR） can mediate cell-specific translation of vsxl mRNA in the bipolar cells of the retinal inner nuclear layer （INL）. vsxl is also transcribed at the early developmental stages prior to eye formation and its spatiotemporal expression patterns are conserved in all the examined vertebrates. In order to determine whether the vsxl 3＇ UTR has a role in regulating the spatiotemporal expression of vsxl during early embryogenesis, we constructed a vsxl UTR-controlled green fluorescent protein （GFP） reporter gene system and examined the GFP expression pattern in goldfish, Carassius auratus, at different developmental stages, Our results indicated that both the vsxl 5＇ UTR and the vsxl 3＇ UTR remarkably repressed GFP expression at transcription level but did not regulate tissue-specific translation at early developmental stages. GFP protein was ubiquitously expressed in the embryos injected with GFP-sensors containing vsxl UTRs before 60 h post-fertilization （hpf）. From hatching stage （72 hpf） onwards, however, GFP protein was specifically expressed in the bipolar cells of the retinal 1NL in the vsxl 3＇UTR-GFP-sensor embryos, but was still ubiquitously expressed in the embryos injected with GFP-sensor lacking vsxl 3＇ UTR. These observations showed a significant difference of vsxl 3＇ UTR-mediated translation between early and late developmental stages and suggested that vsxl 3＇ UTR might not be involved in regulating the spatiotemporal expression of vsxl until hatching stage during embryogenesis.

关键词： vsxl untranslated region gene expression spatiotemporal pattern goldfish embryo

Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China

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Journal of Animal Science and Biotechnology 2014年第4期5卷 471-478页

作者： Xiaoying Li Lihong Zhao Yu Fan Yaxiong Jia Lei Sun shanshan ma Cheng Ji Qiugang ma Jianyun Zhang State Key Laboratory of Animal Nutrition China Agricultural University Beijing Municipal General Station for Animal Husbandry and Veterinary Service Institute of Plant Protection Chinese Academy of Agricultural Sciences

Background：The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.Methods：A total of 55 feed ingredients,including 14 corn,13 wheat bran,11 soybean meal and 17 dried distillers grains with solubles（DDGS） as well as 76 complete swine feeds including 7 creep feeds,14 starter feeds,14 grower feeds,18 grower-finisher feeds,10 gestating sow feeds,and 13 lactating sow feeds were randomly collected from15 swine farms located in the Beijing region of China from July to August 2011.Immunoaffinity clean-up,using High-Performance Liquid Chromatography（HPLC） in combination with UV or Fluorescence Detection,was used for quantitative analysis of aflatoxin B,（AFB,）,deoxynivalenol（DON）,zearalenone（ZEA） and ochratoxin A（OTA） in the ingredients and complete feeds.Results：DON and ZEA were the most prevalent mycotoxins found.DON was detected at percentages of 93,92,54,100 and 97%with a mean level of 1.01,0.44,0.05,1.36 and 0.65 ppm in the samples of corn,wheat bran,soybean meal,DDGS and complete feeds,respectively.The detected percentages of ZEA were 100,100,54,100 and 100 with mean levels of 109.1,14.9,9.2,882.7 and 58.9 ppb in the same samples.In the wheat bran and soybean meal samples,the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7,57 and 7%for corn,and 7,14 and 3%for the complete feeds for AFB,,DON and OTA respectively.DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6,88 and 41%,for AFB,,DON and ZEA,respectively.Conclusions：This paper is the first to present data on the natural occurrence of AFB,,DON,ZEA and OTA in ingredients and complete feeds obtained from swine farms in China＇s Beijing region.The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB

关键词： AflatoxinB1 Beijing region Deoxynivalenol Ochratoxin A Swine feeds Zearalenone

氟化物对生态系统的影响及其环境污染防治策略研究

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黑龙江环境通报 2024年第6期37卷 42-44页

作者：马珊珊唐山市环境监控中心河北唐山063000

本文研究了氟化物对生态系统的影响及其环境污染防治策略,分析了氟化物对水生生态系统和土壤生态系统的影响,研究表明氟化物存在一定的毒性,会对水生动植物和土壤微生物造成损害。此外,氟化物在食物链中积累并传递给食物链顶端的捕食者... 详细信息

本文研究了氟化物对生态系统的影响及其环境污染防治策略,分析了氟化物对水生生态系统和土壤生态系统的影响,研究表明氟化物存在一定的毒性,会对水生动植物和土壤微生物造成损害。此外,氟化物在食物链中积累并传递给食物链顶端的捕食者,进一步影响生态系统的稳定性。在此基础上,提出了减少氟化物排放的策略,包括工业排放控制技术和农业活动氟化物排放控制以及相应的土壤修复方法。同时也需要完善法律法规,制定严格的氟化物排放标准,鼓励科研与技术创新。通过这些措施的实施,可以有效防治氟化物环境污染,保护生态系统的健康和稳定。

关键词：氟化物生态系统环境污染防治策略

Evaluation of Ambient Air Quality and Its Changing Trend in Jinan City during 2013-2020

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Meteorological and Environmental Research 2022年第4期13卷 118-124页

作者： Yang LIU Zhaojun WANG Kaizheng SUN Xuejing DAI Min ZHU shanshan ma Hualing ZHANG Jinan Ecological Environment Monitoring Center of Shandong Province Jinan 250100China

Based on the automatic monitoring data of ambient air in Jinan City from 2013 to 2020,the changing trend and characteristics of air quality in Jinan City during 2013-2020 were analyzed by using the fuzzy comprehensive evaluation,air quality index(AQI)and ambient air quality comprehensive index methods.The three methods are different in principle,purpose of use,and characterization methods,but the conclusions are consistent.The ambient air quality in Jinan City was improved significantly from 2013 to 2020.The prime pollutants were mainly PM_(2.5)and PM_(10),but the impact on air quality declined,and the impact of O_(3)on air quality increased.The complex pollution characteristics were obvious.Air pollution was the most severe in winter and lighter in summer.

关键词： Air quality Fuzzy comprehensive evaluation AQI Air quality comprehensive index

Clinical observation on prevention and treatment of radiation-induced parotid-gland injury in patients with nasopharyngeal carcinoma by Compound Sarcandra Glabra

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Radiation Medicine and Protection 2020年第3期1卷 115-119页

作者： Chang Liu Wenchao Yuan shanshan ma Zhixiao Wei Rensheng Wang Department of Radiotherapy The First Affiliated Hospital of Guangxi Medical UniversityNanning530021China

Objective:To investigate the protective effect of the Compound Sarcandra Glabra on radiation injury of parotid glands in patients with nasopharyngeal carcinoma.Methods:Sixty patients with primary nasopharyngeal carcinoma in the First Affiliated Hospital of Guangxi Medical University from June 2018 to January 2019 were collected,which were divided into treatment group and control group using a random number table.All patients were treated by a combination of 9-field intense-modulated radiotherapy and chemotherapy.The treatment group was given the Compound Sarcandra Glabra orally every day from 3 days before radiotherapy to the end.The degree of xerostomia(dry mouth)of patients was compared between the two groups at the end of radiotherapy and 3 months after radiotherapy by the chi-square test.The maximal adsorption and secretion rates of the parotid glands were compared between groups before radiotherapy,at the end of radiotherapy and 3 months after radiotherapy by the independent sample t-test.Results:The symptoms of dry mouth were alleviated in the treatment group,and the degree of dry mouth significantly differed between groups at the end of radiotherapy and 3 months after radiotherapy(χ2=6.696 and 10.977,Pmaximal adsorption and secretion rates of the parotid glands between groups before radiotherapy(t=0.974 and4.646,P>0.05);however,both variables were significantly higher in the treatment group at the end of radiotherapy and 3 months after radiotherapy(t=2.920 and 5.037;t=2.820 and 2.213,Pma,thereby alleviating the degree of dry mouth after radiotherapy.

关键词： Compound Sarcandra glabra Nasopharyngeal carcinoma Radiation injury Parotid gland