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Spatiotemporal variation of dissolved oxygen in the Ediacaran surface ocean and its implication for oceanic carbon cycling

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Science China Earth Sciences 2023年第8期66卷 1892-1905页

作者： Zihu ZHANG meng CHENG haiyang WANG Xinyang CHEN Wei GUO Chao LI State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

The Ediacaran Period(635–539 Ma)witnessed the largest negative excursion in inorganic carbon isotope(δ^(13)Ccarb)over the Earth’s geological history,also known as the Shuram Excursion(SE)*** occurrence of the SE has been widely attributed to an increase in atmospheric-oceanic oxygen levels and the subsequent oxidation of organic matters in Earth’s surface ***,the oxygen levels in the Ediacaran ocean during the SE remain poorly constrained,limiting our ability to better understand the cause and mechanisms behind the ***,the ratio of I/(Ca+Mg)in carbonate has emerged as an effective proxy for quantifying dissolved oxygen([O_(2)])in the local surface *** this study,we analyzed I/(Ca+Mg)ratios in the Shuiquan Formation at the Mochia-Khutuk(MK)section,which records the SE event in the Tarim *** I/(Ca+Mg)ratio shows synchronous variation withδ^(13)Ccarbin the MK section,with the average value decreasing from 2.2μmol/mol at the bottom of the section to 0.8μmol/mol in the middle and then increasing to 3.4μmol/mol at the very top along with the decline and recovery ofδ^(13)*** to the relationship between I/(Ca+Mg)and oxygen content in minimum oxygen zones of the modern ocean,we infer that[O_(2)]of surface water in the MK section decreased from>20–70μmol/L to<20–70μmol/L during the SE,which may reflect the upwelling of the deep seawater enriched dissolved organic carbon(DOC)and reduced substance(such as Fe^(2+))together with its subsequent consumption of[O2]in the surface *** I/(Ca+Mg)pattern in the MK section is significantly different from those of other contemporaneous SE records on other continents,indicating the surface[O_(2)]in the Ediacaran ocean could have been temporally and spatially *** factors,such as latitude,temperature,productivity,and input of anoxic water masses could play important roles in regulating the surface ocean redox *** observation further suggests that the atm

关键词： I/(Ca+Mg) Carbon isotope Dissolved oxygen Shuram Excursion Oceanic oxygenation

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ITERATIVE METHODS FOR OBTAINING AN INFINITE FAMILY OF STRICT PSEUDO-CONTRACTIONS IN BANACH SPACES

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Acta Mathematica Scientia 2022年第5期42卷 1765-1778页

作者： meng WEN haiyang LI Changsong HU Jigen PENG School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006China School of Science Xi'an Polytechnic UniversityXi'an 710048China Department of Mathematics Hubei Normal UniversityHuangshi 435002China

In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach ***,we show that the sequence defined by the iterative method converges strongly to a common element of the set of fixed points,which is the unique solution of the variational inequality≤0,for z∈⋂_(i=1)^(∞)Γ(S_(i)).The results introduced in our work extend to some corresponding theorems.

关键词： MKC iterative algorithm strict pseudo-contraction β-Lipschitzian d-strongly monotone Banach spaces

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Hypothalamic-Pituitary-Gonadal(HPG)Axis and Transcriptional Regulatory Elements Regulate piwil2 Gene Expression During Gametogenesis and Gonadal Development in Japanese Flounder(Paralichthys olivaceus)

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Journal of Ocean University of China 2020年第6期19卷 1378-1388页

作者： NI Feifei YU haiyang QU Jiangbo meng Lihui LIU Xiumei YAN Weijie CHANG Jing ZHANG Quanqi WANG Xubo YU haiyang Key Laboratory of Marine Genetics and Breeding Ministry of EducationOcean University of ChinaQingdao 266003China College of Life Sciences Yantai UniversityYantai 264005China

The P-element induced wimpy testis(Piwi)proteins,which are associated with PIWI-interacting RNAs(piRNAs),play important roles in meiosis,germ cell division,and germline *** this study,we identified and characterized the Paralichthys olivaceus piwil2 gene,a constituent factor of the piRNA pathways involved in the biogenesis of reproductive *** biological analysis indicated that piwil2,which contains PAZ and PIWI domains,was highly conserved between teleosts and *** piwil2 distribution profile in different tissues confirmed a sexually dimorphic expression pattern,with a higher expression level in *** situ hybridization demonstrated that piwil2 was expressed in the oogonia and oocytes of the ovaries as well as in the Sertoli cells and spermatocytes of the *** piwil2 showed a maternally inherited expression pattern during embryonic development,and was highly expressed during the early embryonic *** luciferase reporters were constructed to determine the transcriptional regulatory mechanisms of *** piwil2 core promoter region was located at−360 bp to−60 ***,some representative sex hormones,including human chorionic gonadotropin,17α-methyltestosterone,and estradiol-17βhad distinct regulatory effects on *** a summery,these results indicate that piwil2,regulated by sex hormones and transcriptional elements,has vital functions in the reproductive cycle and gonadal development.

关键词： piwil2 gametogenesis and gonadal development HPG axis transcriptional regulatory elements Paralichthys olivaceus

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A nanoforest-based humidity sensor for respiration monitoring

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Microsystems & Nanoengineering 2022年第2期8卷 107-117页

作者： Guidong Chen Ruofei Guan meng Shi Xin Dai Hongbo Li Na Zhou Dapeng Chen haiyang Mao Institute of Microelectronics of Chinese Academy of Sciences BeijingChina University of Chinese Academy of Sciences BeijingChina Jiangsu Hinovaic Technologies Co LtdWuxiChina

Traditional humidity sensors for respiration monitoring applications have faced technical challenges,including low sensitivity,long recovery times,high parasitic capacitance and uncalibrated temperature *** overcome these problems,we present a triple-layer humidity sensor that comprises a nanoforest-based sensing capacitor,a thermistor,a microheater and a reference *** compared with traditional polyimide-based humidity sensors,this novel device has a sensitivity that is improved significantly by 8 times within a relative humidity range of 40-90%.Additionally,the integration of the microheater into the sensor can help to reduce its recovery time to 5 *** use of the reference capacitor helps to eliminate parasitic capacitance,and the thermistor helps the sensor obtain a higher *** unique design aspects cause the sensor to have an excellent humidity sensing performance in respiration monitoring ***,through the adoption of machine learning algorithms,the sensor can distinguish different respiration states with an accuracy of 94%.Therefore,this humidity sensor design is expected to be used widely in both consumer electronics and intelligent medical instrument applications.

关键词： humidity sensor overcome

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A Cluster-Based Opportunistic Multicast in Multi-hop Wireless Networks

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Chinese Journal of Electronics 2015年第1期24卷 170-175页

作者： ZHANG haiyang Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications

Multicast has become increasingly important in multi-hop wireless networks for such applications which deliver shared media and data to multiple ***, the existing multicast protocols for wireless network have large control overhead, and cannot adequately take the advantage of broadcast communication mode in multicast structure for sharing the forwarding path. This paper proposes a Cluster-based opportunistic multicast(COM) algorithm, which constructs multicast tree structure based on clusters by utilizing a stability greedy algorithm to achieve the minimum total Cluster-based expected transmission count(CETX). In this multicast tree structure, the edge is created between the kernel sets respectively belonging to two clusters for improving the forwarding efficiency and the stability of this structure. In the process of data distribution, our multi-layer solution combines multicast and opportunistic routing to improve the efficiency of transmission. Simulation results show that COM scheme can achieve the less total number of sending packets, and higher stability than other topology-based solutions and opportunistic multicast.

关键词： Multi-hop wireless network Multicast Opportunistic routing Cluster.

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Palladium-Catalyzed Intermolecular Oxidative Coupling Reactions of （Z）-Enamines with Isocyanides through Selective β-C（sp2）-H and/or C = C Bond Cleavage

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Chinese Journal of Chemistry 2018年第8期36卷 712-715页

作者： Weigao Hu Jia Zheng meng Li Wanqing Wu haiyang Liu Huanfeng Jiang Key Lab of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical Engineering South China University of Technology Guangzhou Guangdong 510640 China

Herein, two efficient palladium-catalyzed intermolecular oxidative coupling reactions of （Z）-enamines with isocyanides via selective β-C（sp2）-H and/or C=C bond cleavage have been developed, leading to controllable chemodivergent and stereoselective construction of a wide range of （E）-β-carbamoylenamine derivatives containing strong intramolecular hydrogen bonds. Furthermore, possible reaction pathways for these transfor- mations are proposed on the basis of preliminary mechanism studies.

关键词： palladium (Z)-enamines isocyanides cleavage reaction oxidative coupling

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Ultra-broadband metamaterial absorbers from long to very long infrared regime

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Light(Science & Applications) 2021年第8期10卷 1462-1473页

作者： Yu Zhou Zheng Qin Zhongzhu Liang Dejia meng haiyang Xu David R.Smith Yichun Liu State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunJilinChina. University of Chinese Academy of Sciences 100049 BeijingChina. Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory of UV Light-Emitting Materials and Technology of Ministry of Education College of PhysicsNortheast Normal University130024 ChangchunChina. Center for Metamaterials and Integrated Plasmonics Duke UniversityP.O.Box 90291DurhamNC 27708USA

Broadband metamaterials absorbers with high absorption,ultrathin thickness and easy configurations are in great demand for many potential *** this paper,we first analyse the coupling resonances in a Ti/Ge/Ti three-layer absorber,which can realise broadband absorption from 8 to 12 *** we experimentally demonstrate two types of absorbers based on the Ti/Ge/Si_(3)N_(4)/Ti *** taking advantage of coupling surface plasmon resonances and intrinsic absorption of lossy material Si_(3)N_(4),the average absorptions of two types of absorbers achieve almost 95%from 8 to 14μm(experiment result:78%from 6.5 to 13.5μm).In order to expand the absorption bandwidth,we further propose two Ti/Si/SiO_(2)/Ti absorbers which can absorb 92%and 87%of ultra-broadband light in the 14-30μm and 8-30μm spectral range,*** findings establish general and systematic strategies for guiding the design of metamaterial absorbers with excellent broadband absorption and pave the way for enhancing the optical performance in applications of infrared thermal emitters,imaging and photodetectors.

关键词： absorber absorption coupling

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Salinity variation and hydrographic dynamics in the early Cambrian Nanhua Basin(South China)

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Science China Earth Sciences 2023年第6期66卷 1268-1278页

作者： meng CHENG Zihu ZHANG Chengsheng JIN Wei WEI haiyang WANG Thomas J.ALGEO Chao LI State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation&Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China College of Resource Environment and Tourism Hubei University of Arts and ScienceXiangyang 441053China School of Earth Science China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Department of Geology University of CincinnatiCincinnati 45221-0013USA

Despite intensive study of the early Cambrian Nanhua Basin(ECNB)in South China,its degree of connectedness to the open ocean remains uncertain,impeding analysis of contemporaneous oceanic redox evolution and its role in the Cambrian *** analyzed bulk-shale B/Ga,a newly proposed proxy for watermass salinity in ancient depositional systems,for three sections(Daotuo,Yuanjia,and Zhalagou)representing a range of water depths in the ECNB and spanning early Cambrian Stages 2 and *** B/Ga proxy records a salinity gradient in the basin,with increasing salinity from shallow-to deep-water areas,particularly during the deposition of black shales of the lower Jiumenchong/Niutitang/Zhalagou *** gradient was probably due to the mixing of freshwater from adjacent landmasses with marine waters within a moderately restricted *** three study sections exhibit a monotonic rise in salinity over the~9-Myr study interval,reflecting increased watermass exchange with the open ocean due to regional tectonic and/or global sea-level *** improved watermass exchange may have weakened water-column stratification and reduced deep-water anoxia in the ECNB,contributing the enhanced oceanic oxygenation along with global environmental controls and further modulating the expression of the Cambrian Explosion recorded in Lower Cambrian sections of South *** study thus highlights the need for comprehensive analyses of hydrographic dynamics in marginal-marine settings that are used to explore co-evolutionary relationships between early animals and environmental oxygen levels.

关键词： B/Ga Boron Gallium Watermass restriction Cambrian Explosion Co-evolution

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Secure separable reversible data hiding of halftone image in blockchain

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The Journal of China Universities of Posts and Telecommunications 2022年第2期29卷 85-96页

作者： Ding haiyang College of Information Engineering Beijing Institute of Graphic CommunicationBeijing 102600China Information Security Center Beijing University of Posts and TelecommunicationsBeijing 100876China

To realize the distributed storage and management of a secret halftone image in blockchain,a secure separable reversible data hiding(RDH)of halftone image in blockchain(SSRDHB)was proposed.A secret halftone image can be used as the original image to generate multiple share images which can be distributed storage in each point of blockchain,and additional data can be hidden to achieve management of each share ***,the secret halftone image was encrypted through Zu Chongzhi(ZUC)algorithm by using the encryption key(EK).Secondly,the method of using odd or even of share data was proposed to hide data,and a share dataset can be generated by using polynomial ***,multiple share images can be obtained through selecting share data,and different additional data can be hidden through controlling odd or even of share data,and additional data can be protected by using data-hiding key(DK).After sharing process,if the receiver has both keys,the halftone image can be recovered and additional data can be revealed,and two processes are *** results show that multiple share images hidden additional data can be obtained through SSRDHB,and the halftone image can be recovered with 100%by picking any part of share images,and one additional data can be revealed with 100%by picking any one share image.

关键词： separable reversible data hiding(RDH) halftone image secret sharing blockchain additional data

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服用二甲双胍的2型糖尿病患者进行碘造影剂检查的指南推荐意见质量评价

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医药导报 2022年第12期41卷 1804-1809页

作者：张爱玲罗旭飞孟海阳张晶敏李纳秦贵军鲁憬莉康建陈耀龙张晓坚郑州大学第一附属医院药学部郑州450052 兰州大学公共卫生学院兰州730000 郑州大学第一附属医院内分泌及代谢科郑州450052 兰州大学基础医学院循证医学中心兰州730000

目的采用AGREEⅡ工具评价服用二甲双胍的2型糖尿病患者行碘造影剂检查的指南推荐意见质量,为医生的临床决策提供参考。方法计算机检索PubMed、EMbase、The Cochrane Library、中国生物医学文献数据库(CBM)、中国知网、万方数据库以及指... 详细信息

目的采用AGREEⅡ工具评价服用二甲双胍的2型糖尿病患者行碘造影剂检查的指南推荐意见质量,为医生的临床决策提供参考。方法计算机检索PubMed、EMbase、The Cochrane Library、中国生物医学文献数据库(CBM)、中国知网、万方数据库以及指南相关数据库网站,查找有关2型糖尿病患者使用二甲双胍进行碘造影剂检查的推荐意见的临床指南,检索时限从建库至2021年11月28日。由2位研究者独立筛选文献、提取资料,4位研究者采用AGREEⅡ工具评价指南质量。结果共纳入7部指南。评价结果显示,皇家澳大利亚和新西兰放射医师学院的指南总得分最高;6个领域中,得分最高的是领域四(清晰性),最低的是领域五(应用性)。纳入指南对服用二甲双胍的2型糖尿病患者进行碘造影剂检查的推荐意见不一致:对于肾小球滤过率(eGFR)>60 mL·min·(1.73 m^(2))^(-1)的患者,有6部指南明确提出检查前后无需停药,仅中国指南要求停用二甲双胍;对eGFR在30~60 mL·min·(1.73 m^(2))^(-1)的患者,指南推荐意见存在较大分歧;对eGFR<30 mL·min·(1.73 m^(2))^(-1)的患者,仅3部指南给出推荐意见。结论目前服用二甲双胍的糖尿病患者进行碘造影剂检查的停药时机的推荐意见存在分歧,而且部分指南的质量有待提高。建议指南制定者应该遵循指南制定和更新的方法学,同时加强对指南各领域,尤其是应用性领域的描述。

关键词：二甲双胍碘造影剂 2型糖尿病指南乳酸酸中毒

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