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A Blind Batch Encryption and Public Ledger-Based Protocol for Sharing Sensitive Data 被引量:1
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作者 Zhiwei Wang Nianhua Yang +2 位作者 qingqing chen Wei Shen Zhiying Zhang 《China Communications》 SCIE CSCD 2024年第1期310-322,共13页
For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and all... For the goals of security and privacy preservation,we propose a blind batch encryption-and public ledger-based data sharing protocol that allows the integrity of sensitive data to be audited by a public ledger and allows privacy information to be preserved.Data owners can tightly manage their data with efficient revocation and only grant one-time adaptive access for the fulfillment of the requester.We prove that our protocol is semanticallly secure,blind,and secure against oblivious requesters and malicious file keepers.We also provide security analysis in the context of four typical attacks. 展开更多
关键词 blind batch encryption data sharing onetime adaptive access public ledger security and privacy
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Data-driven prediction of dimensionless quantities for semi-infinite target penetration by integrating machine-learning and feature selection methods
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作者 qingqing chen Xinyu Zhang +2 位作者 Zhiyong Wang Jie Zhang Zhihua Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期105-124,共20页
This study employs a data-driven methodology that embeds the principle of dimensional invariance into an artificial neural network to automatically identify dominant dimensionless quantities in the penetration of rod ... This study employs a data-driven methodology that embeds the principle of dimensional invariance into an artificial neural network to automatically identify dominant dimensionless quantities in the penetration of rod projectiles into semi-infinite metal targets from experimental measurements.The derived mathematical expressions of dimensionless quantities are simplified by the examination of the exponent matrix and coupling relationships between feature variables.As a physics-based dimension reduction methodology,this way reduces high-dimensional parameter spaces to descriptions involving only a few physically interpretable dimensionless quantities in penetrating cases.Then the relative importance of various dimensionless feature variables on the penetration efficiencies for four impacting conditions is evaluated through feature selection engineering.The results indicate that the selected critical dimensionless feature variables by this synergistic method,without referring to the complex theoretical equations and aiding in the detailed knowledge of penetration mechanics,are in accordance with those reported in the reference.Lastly,the determined dimensionless quantities can be efficiently applied to conduct semi-empirical analysis for the specific penetrating case,and the reliability of regression functions is validated. 展开更多
关键词 Data-driven dimensional analysis PENETRATION Semi-infinite metal target Dimensionless numbers Feature selection
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Outliers rejection in similar image matching
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作者 qingqing chen Junfeng YAO 《Virtual Reality & Intelligent Hardware》 2023年第2期171-187,共17页
Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.... Background Image matching is crucial in numerous computer vision tasks such as 3D reconstruction and simultaneous visual localization and mapping.The accuracy of the matching significantly impacted subsequent studies.Because of their local similarity,when image pairs contain comparable patterns but feature pairs are positioned differently,incorrect recognition can occur as global motion consistency is disregarded.Methods This study proposes an image-matching filtering algorithm based on global motion consistency.It can be used as a subsequent matching filter for the initial matching results generated by other matching algorithms based on the principle of motion smoothness.A particular matching algorithm can first be used to perform the initial matching;then,the rotation and movement information of the global feature vectors are combined to effectively identify outlier matches.The principle is that if the matching result is accurate,the feature vectors formed by any matched point should have similar rotation angles and moving distances.Thus,global motion direction and global motion distance consistencies were used to reject outliers caused by similar patterns in different locations.Results Four datasets were used to test the effectiveness of the proposed method.Three datasets with similar patterns in different locations were used to test the results for similar images that could easily be incorrectly matched by other algorithms,and one commonly used dataset was used to test the results for the general image-matching problem.The experimental results suggest that the proposed method is more accurate than other state-of-the-art algorithms in identifying mismatches in the initial matching set.Conclusions The proposed outlier rejection matching method can significantly improve the matching accuracy for similar images with locally similar feature pairs in different locations and can provide more accurate matching results for subsequent computer vision tasks. 展开更多
关键词 Feature matching Outlier removal Motion consistency Similar image matching Global structures
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Three amino acid residues in the envelope of human immunodeficiency virus type 1 CRF07_BC regulate viral neutralization susceptibility to the human monoclonal neutralizing antibody IgG1b12 被引量:2
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作者 Jianhui Nie Juan Zhao +2 位作者 qingqing chen Weijin Huang Youchun Wang 《Virologica Sinica》 SCIE CAS CSCD 2014年第5期299-307,共9页
The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) ... The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) could recognize conformational epitopes that overlap the CD4 bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182 L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182 V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182 L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4 bs epitopes. 展开更多
关键词 HUMAN IMMUNODEFICIENCY virus type 1 CRF07_BC ENVELOPE GLYCOPROTEIN IgG1b12 NEUTRALIZING antibody single genome amplification
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Dual-boron-source-modified Polysilazane as a Novel Precursor for SiBCN Ceramics
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作者 Qian Zhang Zhihua Yang +2 位作者 Dechang Jia qingqing chen Yu Zhou 《功能材料信息》 2016年第1期57-57,共1页
Here,we demonstrated a novel synthesis of a polyborosilazane(PBSN)precursor using hydroboration and aminolysis reaction synergies to modify polysilazane(PSN).Specifically,borane tetrahydrofuran and boron trichloride h... Here,we demonstrated a novel synthesis of a polyborosilazane(PBSN)precursor using hydroboration and aminolysis reaction synergies to modify polysilazane(PSN).Specifically,borane tetrahydrofuran and boron trichloride hexane were used as dual boron sources,which not only reacted 展开更多
关键词 英语 阅读 理解 陶瓷材料
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Efficient charge relay steering in Pd nanoparticles coupled with the heterojunction for boosting CO_(2)photoreduction to C_(2)H_(6)
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作者 Jiaojiao Fang chengyang Zhu +5 位作者 Lincan Fang Yukai chen Huiling Hu Yan Wu qingqing chen Junjie Mao 《Science China Materials》 SCIE EI CAS CSCD 2024年第9期2949-2956,共8页
Solar-driven CO_(2)conversion to prepare value-added products is highly desirable but challenging.Central to the achievement of multi-carbon products via CO_(2)photoconversion is to break the bottlenecks of C-C coupli... Solar-driven CO_(2)conversion to prepare value-added products is highly desirable but challenging.Central to the achievement of multi-carbon products via CO_(2)photoconversion is to break the bottlenecks of C-C coupling and multi-electron transfer.Herein,a charge relay system consisting of Pd-decorated BiOCl-wrapped CuBi_(2)O_(4)is reported by taking advantage of the synergy of Pd nanoparticles(PdNPs)and heterojunction for efficient CO_(2)-to-C_(2)H_(6)photoconversion.The C_(2)H_(6)production rate reached 167.1µmol g^(-1)h^(-1)with the electron selectivity of 81.1%in the absence of any sacrificial agents.The spectroscopic characterizations indicated that BiOCl nanosheets,acting as the charge relay,directionally transferred the photogenerated electrons from itself and CuBi2O4 nanorods to PdNPs for C-C coupling.The coordinated ensemble of PdNPs and heterojunction significantly elevated the charge separation and transfer efficiency.Moreover,the in-situ spectroscopic analysis supported by theoretical simulations demonstrated that the electron-rich PdNPs generated by the charge relay of PdNPs and heterojunction optimized the CO_(2)-to-C_(2)H_(6)reaction pathway and reduced the energy barrier of the key*CHOCO intermediates.This work develops an innovative strategy to design the multifunctional catalysts for the photoconversion of CO_(2)to value-added carbon products. 展开更多
关键词 charge relay Pd nanoparticles HETEROJUNCTION CO_(2)photoreduction C_(2)H_(6)
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Toward a compact fiber comb with 1.66×10^(-12)instability based on acetylene-filled photonic microcells
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作者 qingqing chen Yongqi Li Shun Wu 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第8期29-34,共6页
We demonstrated an optical fiber frequency comb stabilized to an acetylene-filled photonic microcell.The short-term instability of the comb at 1 s gate time was 1.66×10^(-12)for a 4.2-h measurement in a laborator... We demonstrated an optical fiber frequency comb stabilized to an acetylene-filled photonic microcell.The short-term instability of the comb at 1 s gate time was 1.66×10^(-12)for a 4.2-h measurement in a laboratory environment with air conditioning.This is the best short-term stability reported for a compact fiber comb stabilized to an acetylene-filled photonic microcell at telecom wavelengths.It is particularly significant in the development of compact fiber combs with target instability of 10^(-13).Such a device has the potential to serve as an alternative to GPS in areas lacking signal coverage,including remote locations,regions with adverse weather conditions,and military intelligence areas. 展开更多
关键词 optical frequency comb gas-filled photonic microcell hollow-core photonic crystal fiber
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分散于金属有机框架的单一铜位点促进神经毒剂模拟物降解 被引量:1
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作者 蔡春祺 陈庆庆 +3 位作者 苏红艳 黄鹏程 毛俊杰 吴芳英 《Science China Materials》 SCIE EI CAS CSCD 2023年第6期2475-2482,共8页
神经毒剂是一类毒性极高的化学战剂,因其对人类的巨大危害,亟需实现对它们的脱毒.目前,锆基金属有机框架(Zr-MOFs)是该领域研究最广的催化剂,但仍需开发新的高效的Zr-MOFs催化剂以实现更快速的水解.本文中,我们报道了一种以UiO-66-NH_(2... 神经毒剂是一类毒性极高的化学战剂,因其对人类的巨大危害,亟需实现对它们的脱毒.目前,锆基金属有机框架(Zr-MOFs)是该领域研究最广的催化剂,但仍需开发新的高效的Zr-MOFs催化剂以实现更快速的水解.本文中,我们报道了一种以UiO-66-NH_(2)为载体的铜单原子催化剂,Cu@UiO-66-NH_(2),它能极大促进神经毒剂模拟物的降解.相比于载体UiO-66-NH_(2)本身,这一单原子催化剂展现出显著的催化活性(半衰期约为2分钟)和良好的循环可用性.实验和理论研究均表明分散的单原子铜锚定于氨基而非UiO-66-NH_(2)的Zr6簇,这一螯合方式有利于与底物和产物的结合.因此,和传统的基于Zr-MOFs的催化机理不同,这一新机理能阐明催化效率增强的实质. 展开更多
关键词 金属有机框架 单原子催化剂 神经毒剂 催化机理 催化活性 模拟物 化学战剂 催化效率
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Staphylococcus aureus bloodstream infection in a Chinese tertiary-care hospital:A single-center retrospective study
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作者 cheng Zheng qingqing chen +7 位作者 Sijun Pan Yuanyuan Li Li Zhong Xijiang Zhang Wei Cui Ronghai Lin Gensheng Zhang Shufang Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2023年第12期1503-1505,共3页
To the Editor:Despite major advances in medical care,the incidence and mortality of bloodstream infection(BSI)remain high,which is still a global public health challenge.BSI can be caused by various microorganisms,and... To the Editor:Despite major advances in medical care,the incidence and mortality of bloodstream infection(BSI)remain high,which is still a global public health challenge.BSI can be caused by various microorganisms,and the most common organisms are Escherichia coli,Klebsiella pneumoniae,and Staphylococcus aureus(S.aureus),according to the China Antimicrobial Surveillance Network(CHINET).[1]S.aureus is the third most common cause of BSI,which is associated with shortterm mortality rates of 15–30%,long-term excess mortality,and increased healthcare costs.At present,there are many studies on Gram-negative bacteremia but relatively few on S.aureus bloodstream infection(SA-BSI),especially in China.With the occurrence of new treatments and clinical conditions,such as aging and extensive antibiotic resistance,it is necessary to reanalyze the clinical characteristics and prognosis of SA-BSI. 展开更多
关键词 INFECTION MORTALITY SPITE
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Electronic properties of 2H-stacking bilayer MoS_(2)measured by terahertz time-domain spectroscopy
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作者 Xingjia cheng Wen Xu +5 位作者 Hua Wen Jing Zhang Heng Zhang Haowen Li Francois M.Peeters qingqing chen 《Frontiers of physics》 SCIE CSCD 2023年第5期161-171,共11页
Bilayer (BL) molybdenum disulfide (MoS_(2)) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moiré s... Bilayer (BL) molybdenum disulfide (MoS_(2)) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moiré superlattices. In this work, BL MoS_(2) on sapphire substrate with 2H-stacking structure is fabricated. We apply the terahertz (THz) time-domain spectroscopy (TDS) for examining the basic optoelectronic properties of this kind of BL MoS_(2). The optical conductivity of BL MoS_(2) is obtained in temperature regime from 80 K to 280 K. Through fitting the experimental data with the theoretical formula, the key sample parameters of BL MoS_(2) can be determined, such as the electron density, the electronic relaxation time and the electronic localization factor. The temperature dependence of these parameters is examined and analyzed. We find that, similar to monolayer (ML) MoS_(2), BL MoS_(2) with 2H-stacking can respond strongly to THz radiation field and show semiconductor-like optoelectronic features. The theoretical calculations using density functional theory (DFT) can help us to further understand why the THz optoelectronic properties of BL MoS_(2) differ from those observed for ML MoS_(2). The results obtained from this study indicate that the THz TDS can be applied suitably to study the optoelectronic properties of BL MoS_(2) based twistronic systems for novel applications as optical and optoelectronic materials and devices. 展开更多
关键词 terahertz time-domain spectroscopy bilayer MoS_(2) OPTOELECTRONICS
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Phylogeny of Seven Genomes of Monkeypox Virus—Anhui Province,China,2023
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作者 Wanhang Lu qingqing chen +5 位作者 Xiaomin Wu Jiaqi Li Ming Li Yongkang Xiao Lei Gong Yong Sun 《China CDC weekly》 SCIE 2024年第46期1218-1222,共5页
What is already known about this topic?Monkeypox,first identified in Africa in 1958,is a zoonotic disease caused by monkeypox virus(MPXV).Since January 2022,a global outbreak of mpox has spread to over 100 non-endemic... What is already known about this topic?Monkeypox,first identified in Africa in 1958,is a zoonotic disease caused by monkeypox virus(MPXV).Since January 2022,a global outbreak of mpox has spread to over 100 non-endemic countries.As of June 30,2024,there have been 99,176 confirmed cases and 535 probable cases across 116 countries,resulting in 208 deaths.What is added by this report?This report presents an analysis of the whole genome sequences of seven MPXVs from Anhui Province.We discovered that,compared to the reference sequence(NC_063383.1),these genomes exhibit 91 nucleotide substitutions and 42 amino acid mutations.They are highly similar to genomes of MPXVs that emerged simultaneously in China,Japan,the Republic of Korea,and Portugal,and are classified within the IIb C.1.1 lineage,with multiple transmission chains and no new branch.What are the implications for public health practice?The MPXV in Anhui Province has undergone mutations in areas critical for viral replication,transcription,and immune escape,posing a risk of recurrent outbreaks.Therefore,vigilant mutation monitoring of MPXV is imperative. 展开更多
关键词 Anhui branch chains
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分娩期耻骨骨折合并盆腔血肿一例
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作者 陈晴晴 柯彩萍 王晓怡 《中华产科急救电子杂志》 2022年第1期62-64,共3页
患者36岁,孕4产2,因“顺产后耻骨联合疼痛18d,间断性发热17d”于2019年2月22日23:48收入广州医科大学附属第三医院。孕期定期产前检查(简称“产检”)无特殊。患者身高156cm,孕前体重55kg,体重指数22.6kg/m2。患者于2月5日在当地医院自... 患者36岁,孕4产2,因“顺产后耻骨联合疼痛18d,间断性发热17d”于2019年2月22日23:48收入广州医科大学附属第三医院。孕期定期产前检查(简称“产检”)无特殊。患者身高156cm,孕前体重55kg,体重指数22.6kg/m2。患者于2月5日在当地医院自然临产,分娩时胎儿头部娩出后娩肩困难,予耻骨联合上加压娩出一活男婴,出生体重3700g,新生儿Apgar评分10-10-10分。患者产后即感耻骨联合处疼痛明显,双下肢活动受限。产后4h起床时出现一过性晕厥,数秒后自然清醒,当地医院考虑体位性低血压、低血糖所致,予对症处理并留置导尿管。 展开更多
关键词 体位性低血压 耻骨联合 留置导尿管 定期产前检查 一过性晕厥 对症处理 间断性发热 孕前体重
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功能农业关键科学问题研究进展与“十四五”发展建议 被引量:12
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作者 尹雪斌 赵其国 +9 位作者 印遇龙 陈清清 王张民 宋佳平 王晓丽 林锦钰 王莉莉 刘晓航 张泽洲 张宁 《科学通报》 EI CAS CSCD 北大核心 2022年第6期497-510,共14页
功能农业是赵其国院士在2008年提出的农业新概念,主要是指农产品的营养化、功能化,旨在解决全球性的“隐性饥饿”问题,并重点满足消费者“吃出健康”的新需求.香山科学会议第669次学术讨论会与会专家认为,历经13年的探索,功能农业已初... 功能农业是赵其国院士在2008年提出的农业新概念,主要是指农产品的营养化、功能化,旨在解决全球性的“隐性饥饿”问题,并重点满足消费者“吃出健康”的新需求.香山科学会议第669次学术讨论会与会专家认为,历经13年的探索,功能农业已初步形成了独特的学科和科技创新体系,实现了从“0”到“1”的突破.本文扼要阐述了9个方面关键科学问题及其相关研究进展:(1)通过对全国及区域土壤中矿物质的时空分布特征,反映母质和成土过程对土壤矿物质的含量影响;(2)土壤与作物间矿物质的吸收、转化,如人工根系实验系统(ARE系统)的建立、土壤中矿物质生物有效性的评价方法,以及植物中功能成分的转化机理等;(3)矿物质和重金属密切相关的超富集植物研究;(4)功能农业生产中功能成分对生物和环境影响评价;(5)功能农业长期科学试验站的研究成果;(6)功能农产品所制备的食物在蒸、炒、煮等烹调过程中以及其他加工技术下的功能成分形态变化的相关研究;(7)在健康效应评价方面,对功能性产品对人体健康的影响及其机理,以及相关功能农产品的干预研究;(8)天然富硒营养强化项目的研究;(9)基准物质的研制情况.在功能农业新技术研发方面,概述了包括食品、土壤和植物等功能成分及其形态的快速检测技术,基于功能农业种养一体化的功能畜牧业研究,涉及抗性淀粉、花青素等稻麦功能种质培育,功能物质的精准给肥调控技术等,有关新方法、新设施、新设备的研究进展.但目前我国功能农业总体上尚处于发展初期,创新链条还不完备,科技创新体系缺少国家平台和支持系统性创新的重大项目,与国家战略需求、地方政府发展愿望还不匹配.针对这些问题,本文提出了我国“十四五”期间功能农业的发展目标,并提供了一些发展建议,希望有助于推动我国功能农业实现从“1”到“100”的跨越式发展. 展开更多
关键词 功能农业 隐性饥饿 物质流 功能成分
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江西宜春市明月山地区土壤和多种作物中硒的含量及形态分布特征 被引量:13
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作者 王晓丽 张泽洲 +4 位作者 王张民 陈清清 宋佳平 刘瑛 尹雪斌 《科学通报》 EI CAS CSCD 北大核心 2022年第6期511-519,共9页
硒在土壤-作物系统中的分布特征是天然硒生物营养强化国际合作计划的重要基础.为了调查天然富硒区土壤与农作物中硒的积累特征和分布规律,本研究采集并测定宜春明月山地区土壤和农作物硒含量,利用高效液相色谱-电感耦合等离子体质谱(HPL... 硒在土壤-作物系统中的分布特征是天然硒生物营养强化国际合作计划的重要基础.为了调查天然富硒区土壤与农作物中硒的积累特征和分布规律,本研究采集并测定宜春明月山地区土壤和农作物硒含量,利用高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)测定农作物中5种硒形态含量.结果表明,土壤总硒含量为167~905μg/kg,中位值为373μg/kg,生物可利用硒含量为32~127μg/kg,中位值为53μg/kg;农作物中水稻、蔬菜、水果、茶叶的硒含量分别为9~210、23~282、1~20、30~221μg/kg;不同种类农作物中硒的形态组成不同,水稻中有机硒所占比例为83%,主要为SeMet;蔬菜样品中,茄子、辣椒、空心菜有机硒所占比例分别为45%、65%、68%,硒赋存形态为SeMet、MeSeCys和SeCys2;茶叶样品中有机硒占比为47%,主要以Se(VI)、MeSeCys形态存在.总体而言,宜春明月山地区土壤总硒和生物可利用硒含量高,农作物总硒含量高、硒赋存形态好,辣椒、空心菜、水稻等可作为天然富硒农作物的推荐种植品种. 展开更多
关键词 天然富硒区 宜春 土壤生物可利用硒 硒形态 有机硒
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天然富硒区广西壮族自治区桂平市水稻土壤线虫群落结构特征及其指示意义 被引量:2
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作者 宋佳平 袁林喜 +7 位作者 刘晓东 刘永贤 王张民 陈清清 张泽洲 龙泽东 林锦钰 尹雪斌 《科学通报》 EI CAS CSCD 北大核心 2022年第6期537-547,共11页
发展富硒农业对改善人体健康状况具有重要意义,但目前尚未开展富硒土壤中生态安全评估相关研究.土壤生物是土壤物质循环和能量流动过程的主要调节者,线虫是土壤中数量最丰富的后生动物,其群落结构和多样性对于土壤生态系统的能流通道和... 发展富硒农业对改善人体健康状况具有重要意义,但目前尚未开展富硒土壤中生态安全评估相关研究.土壤生物是土壤物质循环和能量流动过程的主要调节者,线虫是土壤中数量最丰富的后生动物,其群落结构和多样性对于土壤生态系统的能流通道和环境质量等均具有重要的指示意义.本研究选取广西壮族自治区桂平市水稻土壤(总硒为100~900μg/kg)为研究对象,将其分成低硒组、中硒组和高硒组,对其中的线虫群落进行了分析.结果显示,不同硒含量土壤中,线虫群落结构差异显著;相比于低硒组,中硒组及高硒组线虫密度显著增大,cp-2线虫及食真菌线虫相对丰度显著减小,F/B值和结构指数SI值显著减小;随土壤总硒及有效硒含量的增加,线虫密度、连胃属(Chronogaster)线虫相对丰度、棱咽属(Prismatolainus)线虫相对丰度增大,拟丽突属(Acrobeloides)线虫相对丰度、食真菌线虫相对丰度(Fu)、F/B值和结构指数SI减小.硒抑制了群落中的硒敏感线虫,简化了土壤食物网结构.在野外条件下线虫群落对于水稻土壤硒元素具有敏感的响应,可作为水稻土壤硒素水平的生物指示者.本研究为科学评价天然富硒水稻土壤的生态安全提供了数据参考. 展开更多
关键词 水稻土壤 线虫 结构指数 拟丽突属 生物指示者
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Resonance Y-type soliton solutions and some new types of hybrid solutions in the(2+1)-dimensional Sawada–Kotera equation 被引量:3
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作者 Jiaheng Li qingqing chen Biao Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第4期52-57,共6页
In this paper,based on N-soliton solutions,we introduce a new constraint among parameters to find the resonance Y-type soliton solutions in(2+1)-dimensional integrable systems.Then,we take the(2+1)-dimensional Sawada... In this paper,based on N-soliton solutions,we introduce a new constraint among parameters to find the resonance Y-type soliton solutions in(2+1)-dimensional integrable systems.Then,we take the(2+1)-dimensional Sawada–Kotera equation as an example to illustrate how to generate these resonance Y-type soliton solutions with this new constraint.Next,by the long wave limit method,velocity resonance and module resonance,we can obtain some new types of hybrid solutions of resonance Y-type solitons with line waves,breather waves,high-order lump waves respectively.Finally,we also study the dynamics of these interaction solutions and indicate mathematically that these interactions are elastic. 展开更多
关键词 resonance Y-type solitons (2+1)-dimensional Sawada-Kotera equation hybrid solutions
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Anaplasma bovis Infection in Fever and Thrombocytopenia Patients——Anhui Province,China,2021 被引量:3
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作者 Miao Lu qingqing chen +12 位作者 Xincheng Qin Yong Lyu Zhongqiu Teng Kun Li Liang Yu Xiaojing Jin Hongwei Chang Wen Wang Dayin Hong Yong Sun Biao Kan Lei Gong Tian Qin 《China CDC weekly》 2022年第12期249-253,I0005,I0006,共7页
Summary What is already known about this topic?The genus Anaplasma contains seven recognized bacterial species,mainly transmitted by tick bites.The two species,A.phagocytophilum and A.capra,are known commonly to cause... Summary What is already known about this topic?The genus Anaplasma contains seven recognized bacterial species,mainly transmitted by tick bites.The two species,A.phagocytophilum and A.capra,are known commonly to cause diseases in humans.What is added by this report?Anaplasma bovis was initially thought to be only an animal agent until the first patient case was reported in 2019.This study investigated another two patients who became sick within one month in the same township and were infected with A.bovis in Anhui Province. 展开更多
关键词 ANHUI Province. initially
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Methane and nitrous oxide fluxes from four tundra ecotopes in Ny-lesund of the High Arctic 被引量:1
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作者 qingqing chen Renbin Zhu +1 位作者 Qing Wang Hua Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第7期1403-1410,共8页
During the summers of 2008 and 2009, net methane(CH4) and nitrous oxide(N2O) fluxes were investigated from 4 tundra ecotopes: normal lowland tundra(LT), bird sanctuary tundra(BT), the tundra in an abandoned c... During the summers of 2008 and 2009, net methane(CH4) and nitrous oxide(N2O) fluxes were investigated from 4 tundra ecotopes: normal lowland tundra(LT), bird sanctuary tundra(BT), the tundra in an abandoned coal mine(CT) and the tundra in scientific bases(ST) in Ny-Alesund of the High Arctic. Tundra soils in CT(184.5 ± 40.0 μg CH4/(m2·hr)) and ST(367.6 ± 92.3 μg CH4/(m2·hr)) showed high CH4 emissions due to the effects of human activities, whereas high CH4 uptake or low emission occurred in the soils of LT and BT.The lowland tundra soils(mean,-4.4-4.3 μg N2O/(m2·hr)) were weak N2 O sources and even sinks. Bird activity increased N2 O emissions from BT with the mean flux of7.9 μg N2O/(m2·hr). The mean N2 O fluxes from CT(45.4 ± 10.2 μg N2O/(m2·hr)) and ST(78.8 ± 18.5 μg N2O/(m2·hr)) were one order of magnitude higher than those from LT and BT, indicating that human activities significantly increased N2 O emissions from tundra soils. Soil total carbon and water regime were important factors affecting CH4 fluxes from tundra soils. The N2 O fluxes showed a significant positive correlation with ammonia nitrogen(NH4+-N) contents(r = 0.66, p 〈 0.001) at all the observation sites, indicating that ammonia nitrogen(NH4+-N) content acted as a strong predictor for N2 O emissions from tundra soils. The CH4 and N2O fluxes did not correspond to the temperature variations of soil at 0-15 cm depths.Overall our results implied that human activities might have greater effects on soil CH4 and N2O emissions than current climate warming in Ny-Alesund, High Arctic. 展开更多
关键词 Tundra soilMethaneNitrous oxideArcticGreenhouse gases
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Highly-efficient photosensitizer based on AIEgen-decorated porphyrin for protein photocleaving
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作者 Qiang Wang qingqing chen +6 位作者 Guoyu Jiang Mengting Xia Mengjiao Wang Yongdong Li Xiaoming Ma Jianguo Wang Xinggui Gu 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第11期1965-1968,共4页
An AIEgen decorated porphyrin(TPETPyP)was easily obtained through a one-step reaction.The bulky TPE in TPETPyP greatly impeded the intermolecularπ-πstacking of the porphyrin core,which significantly suppressed aggre... An AIEgen decorated porphyrin(TPETPyP)was easily obtained through a one-step reaction.The bulky TPE in TPETPyP greatly impeded the intermolecularπ-πstacking of the porphyrin core,which significantly suppressed aggregation-caused quenching(ACQ)effect of TPETPyP in aqueous solution.The four pyridinium salts formed in TPETPyP also render the whole molecule water solubility,which eliminated its aggregation.TPETPyP exhibited 1O2 quantum yield as high as 0.85 in PBS.Moreover,it also showed high binding affinity to proteins,the major biotarget of 1O2.The high 1O2 quantum yield plus the great binding ability of TPETPyP toward proteins makes it a highly-efficient protein photocleaving agent.Protein electrophoresis experiments demonstrated that TPETPyP can photocleave BSA upon visible light irradiation,indicating that TPETPyP can act as a promising photosensitizer(PS)in PDT.The work here will provide a facile strategy to utilize AIEgens modified traditional PSs for photodynamic therapy(PDT). 展开更多
关键词 AIEgen PORPHYRIN Singlet oxygen quantum yield Protein photoclevage
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Cysteine-Specific Bioconjugation and Stapling of Unprotected Peptides by Chlorooximes
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作者 qingqing chen Tengfang Long +5 位作者 Jie Zheng Wangjian Sheng Shuaishuai Sun Wei Wei Jing Zhao Huan Wang 《CCS Chemistry》 CAS 2022年第10期3355-3363,共9页
Cyclic peptides have found applications in fields ranging from drug discovery to nanomaterials.Peptide stapling reagents crosslink two or more residues in peptides to generate macrocycles of diverse topology and intro... Cyclic peptides have found applications in fields ranging from drug discovery to nanomaterials.Peptide stapling reagents crosslink two or more residues in peptides to generate macrocycles of diverse topology and introduce linker units that might directly impact the properties and biological functions of cyclic peptides.Herein,we demonstrate that chlorooxime derivatives are cysteine-specific peptide bioconjugation and stapling reagents that generate stable thiohydroximate linkages. 展开更多
关键词 cyclic peptides peptide stapling BIOCONJUGATION chlorooximes CYSTEINE
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