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[Solid-phase extraction coupled with high performance liquid chromatography-triple quadrupole mass spectrometry for simultaneous determination of seven coumarins in water samples from drinking water treatment plants]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 78-86页

作者： Wen-mei Jiao Jing-Ming Yang Ce Xu Fu-Kang gao Lu-Yao Shen Yu-Bo Yuan Zhi-Fen Guo Guang Huang School of Life Sciences and Chemical Engineering Jiangsu Second Normal University Nanjing 211200 China. School of Stomatology Nanjing Medical University Nanjing 210029 China. School of Public Health Nanjing Medical University Nanjing 211166 China. Key Laboratory of Modern Toxicology Ministry of Education School of Public Health Nanjing Medical University Nanjing 211166 China.

Chlorinated coumarins, which are as cytotoxic as highly toxic halobenzoquinones toward CHO-K1 cells, have recently been identified as disinfection byproducts in drinking water disinfection processes. Therefore, detecting coumarins in water samples collected at various stages from drinking water treatment plants helps assess the formation of chlorinated coumarins in drinking water. Hence, a simple, rapid, accurate, and sensitive method for quantifying coumarins in water samples is required. In this study, a method was developed based on solid-phase extraction coupled with high performance liquid chromatography-triple-quadrupole mass spectrometry for analyzing seven coumarins in water samples from drinking water treatment plants, including 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, 8-chloro-7-hydroxycoumarin, coumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin. Sample pretreatment involved solid-phase extraction using HLB columns, followed by elution with water and methanol, each containing 0.25% formic acid. The extracted solution was separated via gradient elution using a Phenomenex Luna C18 column (100 mm×2.0 mm, 3 mm) with 0.1% formic acid aqueous solution and methanol as the mobile phases, with analytes detected by triple-quadrupole mass spectrometry equipped with electrospray ionization source in multiple reaction monitoring mode. The matrix effect, precision, and accuracy of the developed method were investigated using raw and treated water as matrices. Matrix effects of 0.84-1.12 were recorded for the detection of 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, and coumarin in raw water, while values of 0.67-0.70 were recorded for 8-chloro-7-hydroxycoumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin in finished water. The three chlorinated coumarins exhibited matrix effects above 0.80 after the finished water matrix had been diluted four times. These re

关键词： coumarins disinfection byproducts drinking water high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) solid-phase extraction (SPE)

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儿童突眼的CT诊断

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实用放射学杂志 2003年第12期19卷 1067-1069页

作者：高雪梅王振豫周志刚程敬亮江波赵艺蕾郭华郑州大学第一附属医院放射科郑州大学第一附属医院放射科河南郑州450052

目的　探讨儿童突眼的CT表现特点。方法　对 3 1例儿童突眼患者的眶部CT表现进行回顾性分析。 3 1例中 2 5例经手术病理证实 ,6例为临床随访。结果　眶内炎症 5例 ,其中蜂窝织炎 2例、肌锥外脓肿 1例、炎性假瘤 2例。眶内肿瘤 2 6例 ,... 详细信息

目的　探讨儿童突眼的CT表现特点。方法　对 3 1例儿童突眼患者的眶部CT表现进行回顾性分析。 3 1例中 2 5例经手术病理证实 ,6例为临床随访。结果　眶内炎症 5例 ,其中蜂窝织炎 2例、肌锥外脓肿 1例、炎性假瘤 2例。眶内肿瘤 2 6例 ,其中毛细血管瘤 4例 ,皮样囊肿 3例 ,视神经胶质瘤 3例 ,神经鞘瘤 1例 ,骨化性纤维瘤 1例 ,横纹肌瘤 1例 ,神经纤维瘤病Ⅰ型 2例 ,泪腺混合瘤和腺样囊性癌各 1例 ,横纹肌肉瘤 5例 ,视网膜母细胞瘤 3例 ,转移性神经母细胞瘤 1例。结论　儿童突眼的CT表现各有其特点 ,结合临床多数可作出定性诊断

关键词：眼球突出儿童体层摄影,X线计算机

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Chinese Cyber Threat Intelligence Named Entity Recognition via RoBERTa-wwm-RDCNN-CRF

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Computers, Materials & Continua 2023年第10期77卷 299-323页

作者： zhen zhen Jian gao School of Information Network Security People’s Public Security University of ChinaBeijing100038China Key Laboratory of Safety Precautions and Risk Assessment Ministry of Public SecurityBeijing102623China

In recent years,cyber attacks have been intensifying and causing great harm to individuals,companies,and *** mining of cyber threat intelligence(CTI)can facilitate intelligence integration and serve well in combating cyber *** Entity Recognition(NER),as a crucial component of text mining,can structure complex CTI text and aid cybersecurity professionals in effectively countering ***,current CTI NER research has mainly focused on studying English *** the limited studies conducted on Chinese text,existing models have shown poor *** fully utilize the power of Chinese pre-trained language models(PLMs)and conquer the problem of lengthy infrequent English words mixing in the Chinese CTIs,we propose a residual dilated convolutional neural network(RDCNN)with a conditional random field(CRF)based on a robustly optimized bidirectional encoder representation from transformers pre-training approach with whole word masking(RoBERTa-wwm),abbreviated as *** are the first to experiment on the relevant open source dataset and achieve an F1-score of 82.35%,which exceeds the common baseline model bidirectional encoder representation from transformers(BERT)-bidirectional long short-term memory(BiLSTM)-CRF in this field by about 19.52%and exceeds the current state-of-the-art model,BERT-RDCNN-CRF,by about 3.53%.In addition,we conducted an ablation study on the encoder part of the model to verify the effectiveness of the proposed model and an in-depth investigation of the PLMs and encoder part of the model to verify the effectiveness of the proposed *** RoBERTa-wwm-RDCNN-CRF model,the shared pre-processing,and augmentation methods can serve the subsequent fundamental tasks such as cybersecurity information extraction and knowledge graph construction,contributing to important applications in downstream tasks such as intrusion detection and advanced persistent threat(APT)attack detection.

关键词： Cybersecurity cyber threat intelligence named entity recognition

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限流电阻柜对移圈调压器空载合闸保护作用的研究

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通信电源技术 2020年第1期37卷 126-128页

作者：陈英豪高美珍周水威汪湘洪家平湖北师范大学计算机科学与技术学院湖北黄石435002 湖北师范大学物理与电子科学学院湖北黄石435002 中国人民解放军91919部队湖北黄冈438000 湖北师范大学经济与管理学院湖北黄石435002

针对某高压系统移圈调压器故障原因进行了探讨,从理论上研究了励磁涌流对调压器的破坏机理;研究了采取在调压器前端串入限流启动电阻的方法来减小励磁涌流对调压器破坏性作用的可行性。经过实测数据对比表明,加装限流电阻后,励磁涌流的... 详细信息

针对某高压系统移圈调压器故障原因进行了探讨,从理论上研究了励磁涌流对调压器的破坏机理;研究了采取在调压器前端串入限流启动电阻的方法来减小励磁涌流对调压器破坏性作用的可行性。经过实测数据对比表明,加装限流电阻后,励磁涌流的幅值和持续时间下降都非常明显,操作过电压也得到抑制,具有较强的实用性。

关键词：限流电阻励磁涌流过电压

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Performance of Three Adelphocoris spp.(Hemiptera: Miridae) on Flowering and Non-flowering Cotton and Alfalfa

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Journal of Integrative Agriculture 2014年第8期13卷 1727-1735页

作者： gao zhen PAN Hong-sheng LIU Bing LU Yan-hui LIANG Ge-mei State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

The genus Adelphocoris（Hemiptera： Miridae） is a group of key insect pests in cotton fields in China that includes three dominant species： A. suturalis（Jakovlev）, A. lineolatus（Goeze） and A. fasciaticollis（Reuter）. Previous field surveys have found that adults of these Adelphocoris species usually move onto specific host plants when the plants enter the flowering stage. To determine the potential trade-offs for this host-plant preference behavior, the performance of these three Adelphocoris spp. on flowering and non-flowering cotton and alfalfa were compared in the laboratory. The results showed that Adelphocoris spp. had significantly higher nymphal developmental and survival rates, along with increased adult longevity and fecundity on flowering cotton and alfalfa than on non-flowering plants of either species. In addition, compared with cotton plants, alfalfa generally promoted better performance of these three Adelphocoris species, especially for A. lineolatus. Simple correlation analysis indicated that female adult longevity was positively correlated to male adult longevity and female fecundity, and female fecundity was positively correlated to nymphal development and survival rates. This study demonstrated a positive correlation between adult preference and offspring/adult performance for all three Adelphocoris species, with no evidence of any trade-offs for this preference for flowering host plants. These findings support the hypothesis that hemimetabolous insects such as mirid bugs have positive adult preference-adult/nymphal performance relationships, which is likely due to the similar feeding habits and nutritional requirements of adults and nymphs.

关键词： Adelphocoris lineolatus Adelphocoris suturalis Adelphocoris fasciaticollis preference-performance relationship cotton alfalfa flowering stage

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Multi-Panel Extra-Large Scale MIMO Based Joint Activity Detection and Channel Estimation for Near-Field Massive IoT Access

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China Communications 2023年第5期20卷 232-243页

作者： zhen gao Hanlin Xiu Yikun mei Anwen Liao Malong Ke Chun Hu Mohamed-Slim Alouini School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China MIIT Key Laboratory of Complex-Field Intelligent Sensing Beijing Institute of TechnologyBeijing 100081China The Advanced Technology Research Institute of Beijing Institute of Technology Jinan 250307China Yangtze Delta Region Academy of Beijing Institute of Technology(Jiaxing) Jiaxing 314019China Electrical Engineering Program Division of Physical Sciences and EngineeringKing Abdullah University of Science and TechnologyThuwal 23955Saudi Arabia

The extra-large scale multiple-input multiple-output(XL-MIMO)for the beyond fifth/sixth generation mobile communications is a promising technology to provide Tbps data transmission and stable access ***,the extremely large antenna array aperture arouses the channel near-field effect,resulting in the deteriorated data rate and other challenges in the practice communication ***,multi-panel MIMO technology has attracted extensive attention due to its flexible configuration,low hardware cost,and wider *** combining the XL-MIMO and multi-panel array structure,we construct multi-panel XL-MIMO and apply it to massive Internet of Things(IoT)***,we model the multi-panel XL-MIMO-based near-field channels for massive IoT access scenarios,where the electromagnetic waves corresponding to different panels have different angles of arrival/departure(AoAs/AoDs).Then,by exploiting the sparsity of the near-field massive IoT access channels,we formulate a compressed sensing based joint active user detection(AUD)and channel estimation(CE)problem which is solved by AMP-EM-MMV *** simulation results exhibit the superiority of the AMP-EM-MMV based joint AUD and CE scheme over the baseline algorithms.

关键词： extra-large scale MIMO massive IoT access active user detection channel estimation multipanel approximate message passing

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Identification of Quantitative Trait Loci for Rice Quality in a Population of Chromosome Segment Substitution Lines

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Journal of Integrative Plant Biology 2009年第5期51卷 500-512页

作者： Wei Hao mei-zhen Zhu Ji-Ping gao Shi-Yong Sun Hong-Xuan Lin National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai 200032 China

The demand for high quality rice represents a major issue in rice production. The primary components of rice grain quality include appearance, eating, cooking, physico-chemical, milling and nutritional qualities. Most of these traits are complex and controlled by quantitative trait loci （QTLs）, so the genetic characterization of these traits is more difficult than that of traits controlled by a single gene. The detection and genetic identification of QTLs can provide insights into the genetic mechanisms underlying quality traits. Chromosome segment substitution lines （CSSLs） are effectivetools used in mapping QTLs. In this study, we constructed 154 CSSLs from backcross progeny （BC3F2） derived from a cross between ＇Koshihikari＇（an Oryza sativa L. ssp. japonica variety） as the recurrent parent and ＇Nona Bokra＇（an O. sativa L. ssp. indica variety） as the donor parent. In this process, we carried out marker-assisted selection by using 102 cleaved amplified polymorphic sequence and simple sequence repeat markers covering most of the rice genome. Finally, this set of CSSLs was used to identify QTLs for rice quality traits. Ten QTLs for rice appearance quality traits were detected and eight QTLs concerned physico-chemical traits. These results supply the foundation for further genetic studies and breeding for the improvement of grain quality.

关键词： appearance quality traits chromosome segment substitution lines Oryza sativa physico-chemical quality traits quantitative trait loci

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Yinyanghuo(Herba Epimedii Brevicornus) and its components for chronic obstructive pulmonary disease:preclinical evidence and possible mechanisms

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Journal of Traditional Chinese Medicine 2023年第2期43卷 386-396页

作者： WANG Yide gao zhen Department of Respiration Traditional Chinese Medicine Hospital Affiliated to Xinjiang Medical UniversityUrumqi 830000China Department of Integrative Medicine Huashan hospital of Fudan UniversityShanghai 200040China

OBJECTIVE:To integrate Meta-analysis and bioinformatics strategies in the preliminary exploration of the potential mechanism of Yinyanghuo(Herba Epimedii Brevicornus) and its extract in treating chronic obstructive pulmonary disease(COPD).METHODS:First,Meta-analysis was carried *** Chinese and English literature of Yinyanghuo(Herba Epimedii Brevicornus) in treating COPD was searched using the systematic strategy of combining subject words with free *** included studies were evaluated by the SYRCLE risk bias assessment tool,after which the review manager software was used to combine the effect quantities for statistical ***,based on bioinformatics technology,the active ingredients and their targets of Yinyanghuo(Herba Epimedii Brevicornus) were screened,and the intersection genes were obtained by mapping and comparing with the targets of *** "medicinal materials-compounds-targets model" was constructed,and the key pathways were ***,the core target was docked with important ***:A total of 8 studies were included in the *** results showed that the Yinyanghuo(Herba Epimedii Brevicornus) group could significantly downregulate pro-inflammatory factors such as tumor necrosis factor-α(TNF-α) and interleukin(IL)-8 and increase the expression of anti-inflammatory factors and antioxidant factors such as IL-10 and phospho-protein kinase B(pAKT) in the COPD model(all P < 0.05).A total of 23 active components and 102 corresponding target genes of Yinyanghuo(Herba Epimedii Brevicornus) were obtained by bioinformatics technology,among which 17 compounds and 63 targets were closely related to *** results of enrichment analysis mainly included TNF signaling pathway,phosphoinositide 3-kinase(PI3K)/Akt signaling pathway,cancer signaling pathway,and other inflammatory reactions,oxidative stress,and tumorrelated *** molecular docking results showed that the binding energy fractions of the top five components

关键词： Yinyanghuo(Herba Epimedii Brevicornus) pulmonary disease chronic obstructive Meta-analysis computational biology

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Structure and Mechanical Properties of Al-based Gradient Composites Reinforced with Primary Si and Mg_2Si Particles through Centrifugal Casting

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 813-818页

作者：翟彦博 MA Xiuteng mei zhen College of Engineering and Technology Southwest University Congqing Machine Tool (Group) Co. Ltd.

The structure and mechanical properties of a new type of Al-based discontinuous gradient composites prepared by using the ternary AI-19Si-5Mg alloys as the raw material adopting the centrifugal casting method were investigated. Structurally, the composites are divided into two zones： a reinforced zone with the high volume fraction of primary Si and Mg2Si particles and an unreinforced zone with no or a few particles. In the reinforced zone, the primary particles are evenly distributed, with the sizes of the primary Si particles 80-120 μm, and that of primary Mg2Si particles 20-50 μm. The properties test results show the reinforced zone has higher Rockwell hardness and better wear resistance than the unreinforced zone, due to the complementary reinforcement relationship between the primary Si and Mg2Si particles and their high volume fraction.

关键词： gradient composites centrifugal casting primary Si primary Mg2Si

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Feasibility of LTE-Based GEO Satellite Mobile Communication Systems to Support VoIP for Handheld Terminals

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Chinese Journal of Electronics 2019年第4期28卷 829-834页

作者： DING Dan gao zhen CHENG Naiping Department of Electronic and Optical Engineering Space Engineering University School of Electrical and Information Engineering Tianjin University

To facilitate the integration of terrestrial and satellite mobile communication systems in the future,the new generation of satellite mobile communication system should be Long-term evolution(LTE)-*** LTE, voice is carried by Internet protocol(IP)packets(voice over IP, VoIP). The feasibility of LTEbased Geosynchronous earth orbit(GEO) satellite mobile communication systems for Vo IP is discussed. Detailed link budgets are created for typical handheld *** effectiveness of Physical resource block(PRB)bundling and Transmission time interval(TTI) bundling for the capacity improvement of downlink and uplink are evaluated, and further uplink improvement for low level terminals by Narrowband resource block(NRB)scheme is also studied. The analysis results show that the downlink VoIP transmission is mainly power limited, and optimization of PRB or TTI bundling can maximize the capacity. For uplink, only highlevel terminals can support VoIP under the normal LTE frame structure, and TTI bundling and Resource block(RB) block techniques can help the low-level terminals support VoIP transmission.

关键词： Satellite mobile communications Geosynchronous earth orbit(GEO) Long-term evolution(LTE) Voice over internet protocol(VoIP) Handheld terminals

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