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Heavy metals in maternal and cord blood in Beijing and their efficiency of placental transfer

Journal of Environmental Sciences 2019年第6期31卷 99-106页

作者： aijing li Taifeng Zhuang Jianbo Shi Yong liang Maoyong Song Institute of Environment and Health Jianghan University Key Laboratory of Environmental Nanotechnology and Health Effects Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Department of Pediatrics Beijing Obstetrics and Gynecology Hospital Capital Medical University University of Chinese Academy of Sciences

This study aimed to determine the effect of exposure to heavy metals in pregnant women in Beijing, China. We also evaluated the association of these heavy metals with birth weight and length of newborns. We measured the levels of 10 heavy metals,including lead(Pb), titanium(Ti), manganese(Mn), nickel(Ni), cadmium(Cd), chromium(Cr), antimony(Sb), stannum(Sn), vanadium(V), and arsenic(As), in 156 maternal and cord blood pairs. An inductively coupled plasma mass spectrometry method was used for measurement. Pb, As, Ti, Mn, and Sb showed high detection rates(> 50%) in both maternal and cord blood. Fourteen(9%) mothers had blood Pb levels greater than the United States Center for Disease Control allowable threshold limit for children(50 μg/L).In prenatal exposure to these heavy metals, there was no significant association between any heavy metal and birth weight/length. Moreover, we estimated the placental transfer efficiency of each heavy metal, and the median placental transfer efficiency ranged from 49.6%(Ni) to 194%(Mn)(except for Cd and Sn). The level and detection rate of Cd in maternal blood were much higher than that in cord blood, which suggested that Cd had difficulty in passing the placental barrier. Prospective research should focus on the source and risk of heavy metals in non-occupationally exposed pregnant women in Beijing.

关键词： Heavy metal Maternal blood Cord blood Newborn Placental transfer efficiency

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Association between serum levels of TSH and free T4 and per- and polyfluoroalkyl compounds concentrations in pregnant women

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Journal of Environmental Sciences 2023年第2期124卷 11-18页

作者： aijing li Jian Hou Jianjie Fu YinanWang Yifei Hu Taifeng Zhuang Menglong li Maoyong Song Guibin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of ScienceBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Department of Epidemiology and Biostatistics College of Public HealthZhengzhou UniversityZhengzhou 450001China Beijing Obstetrics and Gynecology Hospital Capital Medical UniversityBeijing 100026China Department of Child Adolescent Health and Maternal CareSchool of Public HealthCapital Medical UniversityBeijing 100069China

Many per-and polyfluoralkyl substances(PFASs)may disrupt maternal thyroid hormone homeostasis in *** should be raised regarding the PFASs exposure in pregnant women because thyroid hormones are involved in the early development of the *** this study,we measured the concentrations of 13 PFASs,including five novel shortchain PFASs,in serum from 123 pregnant women in Beijing,*** regression models were used to investigate the association between thyroid-stimulating hormone(TSH)or free thyroxine(FT4)levels and PFASs concentrations under consideration of the impacts of pregnancy-induced physiological *** found that perfluorobutanoic acid(PFBA)(β=0.189,95%CI=-0.039,0.417,p=0.10)and perfluorodecanoic acid(PFDA)(β=-0.554,95%CI=-1.16,0.049,p=0.071)were suggestive of significant association with TSH in thyroid peroxidase antibody(TPOAb)negative *** association was observed between all PFASs and FT4 levels after controlling for these confounding factors,such as BMI,gestational weight gain and maternal *** findings suggest that it should pay more attention to the association between thyroid hormone levels and short-chain PFASs *** studies could consider a greater sample and the inclusion of other clinical indicators of thyroid function,such as free T3 and total T3.

关键词： Per-and polyfluoralkyl substances Short-chain perfluoroalkyl acids Thyroid hormone Thyroid peroxidase antibody

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Eliminating Explicit Contention from Channel Access in Distributed Wireless Networks

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China Communications 2019年第5期16卷 70-82页

作者： aijing li Chao Dong Fan Wu Shaojie Tang Guihai Chen Qihui Wu Department of Computer Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Communications Engineering PLA Army Engineering UniversityNanjing 210007China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Information Systems University of Texas at DallasTexas 75080USA

Emerging techniques such as WiFi direct makes the objective of always-on be true. People can easily chat and share files with nearby friends even without AP(Access Point) or cellular coverage. In this paper, we focus on the channel efficiency issue of APfree Wi-Fi networks, which can be easily constructed in the subway, in a high-speed railway, or when camping in the wild. Today IEEE 802.11 DCF is the most commonly used MAC protocol for Wi-Fi networks, however, due to the control messages and backoff time, channel efficiency in high data rate networks can be extremely low. To solve this, we propose CD-MAC, which allows control messages to be transmitted with data packets concurrently, and thus eliminates the overheads of backoff and explicit contention. To maintain the reception reliability, we redesign the control messages and use signal detection in PHY instead of bits decoding to detect them. In MAC layer, CD-MAC is built upon our Correlation Detection based PHY. We have implemented and evaluated CD-MAC using USRP N210. Evaluation results show that CD-MAC can achieve over 95.5% channel efficiency and provide throughput gains of up to 80%, 60%, and 29.1% compared with DCF, 802.11 ec, and back2F, respectively.

关键词： implicit contention correlation detection media access ad hoc networks OFDM USRP

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An exceptionally well-preserved herbaceous eudicot from the Early Cretaceous(late Aptian–early Albian)of Northwest China

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National Science Review 2021年第12期8卷 46-54页

作者： Baoxia Du Mingzhen Zhang Bainian Sun aijing li Jing Zhang Defei Yan Sanping Xie Jingyu Wu Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Key Laboratory of Petroleum and Resources Gansu Province

A fossil eudicot, Gansufructus saligna gen. et sp. nov., is reported from the Early Cretaceous(late Aptian–early Albian) of the Gansu Province, Northwest China, based on numerous well-preserved axes with attached leaves and infructescences. The leaves are alternate, short petiolate and linear-lanceolate with low rank pinnate to reticulate venation. The infructescences are loose panicles bearing fruits in different stages of maturity, each containing four partly free carpels borne in a whorled arrangement. Each carpel has three to five seeds borne along its ventral margin. The nature of the leaves and axes indicates a terrestrial,herbaceous habit. In general organization, Gansufructus is closely similar to the fruit-bearing axes of Sinocarpus decussatus from the Early Cretaceous Jehol Biota, as well as other more or less contemporaneous angiosperms from the Far East, which together provide evidence of diverse eudicot angiosperms of low stature colonizing areas close to environments of deposition.

关键词： eudicot Early Cretaceous Northwest China Jehol Biota Gansufructus paleoecology

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Progress of Research on the Effect of Dietary Care on Patients with Gastritis and Gastric Ulcers

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Journal of Clinical and Nursing Research 2024年第2期8卷 201-205页

作者： aijing li Gucheng Town Center Health Center Shen CountyLiaocheng 252432Shandong ProvinceChina

Gastritis gastric ulcer is a common disease of the digestive system,which has a serious impact on the quality of life and health of affected *** care is one of the important measures to treat and prevent gastritis gastric *** paper reviews the research progress on the impact of dietary care on patients with gastritis and gastric ulcers,including dietary behavioral intervention,dietary habit cultivation,dietary hygiene education,and nutritional *** have shown that rational dietary care was able to improve the clinical symptoms of patients,regulate the intestinal microbial community,anti-inflammatory,antioxidant,and other pathways to improve the pathophysiological state of patients with gastritis and gastric ulcer and prevent ***,dietary care is of great significance to patients with gastritis and gastric ulcers.

关键词： Dietary care Gastritis Gastric ulcer Research progress

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DDoS Attack Autonomous Detection Model Based on Multi-Strategy Integrate Zebra Optimization Algorithm

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Computers, Materials & Continua 2025年第1期82卷 645-674页

作者： Chunhui li Xiaoying Wang Qingjie Zhang Jiaye liang aijing Zhang School of Information Engineering Institute of Disaster PreventionLangfang065201China Langfang Key Laboratory of Network Emergency Protection and Network Security Langfang065201China

Previous studies have shown that deep learning is very effective in detecting known ***,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convolutional Neural Networks(CNN)combined with LSTM,and so on are built by simple stacking,which has the problems of feature loss,low efficiency,and low ***,this paper proposes an autonomous detectionmodel for Distributed Denial of Service attacks,Multi-Scale Convolutional Neural Network-Bidirectional Gated Recurrent Units-Single Headed Attention(MSCNN-BiGRU-SHA),which is based on a Multistrategy Integrated Zebra Optimization Algorithm(MI-ZOA).The model undergoes training and testing with the CICDDoS2019 dataset,and its performance is evaluated on a new GINKS2023 *** hyperparameters for Conv_filter and GRU_unit are optimized using the Multi-strategy Integrated Zebra Optimization Algorithm(MIZOA).The experimental results show that the test accuracy of the MSCNN-BiGRU-SHA model based on the MIZOA proposed in this paper is as high as 0.9971 in the CICDDoS 2019 *** evaluation accuracy of the new dataset GINKS2023 created in this paper is *** to the MSCNN-BiGRU-SHA model based on the Zebra Optimization Algorithm(ZOA),the detection accuracy on the GINKS2023 dataset has improved by 5.81%,precisionhas increasedby 1.35%,the recallhas improvedby 9%,and theF1scorehas increasedby 5.55%.Compared to the MSCNN-BiGRU-SHA models developed using Grid Search,Random Search,and Bayesian Optimization,the MSCNN-BiGRU-SHA model optimized with the MI-ZOA exhibits better performance in terms of accuracy,precision,recall,and F1 score.

关键词： Distributed denial of service attack intrusion detection deep learning zebra optimization algorithm multi-strategy integrated zebra optimization algorithm

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Establishment of an astronomical time scale for the Shizigou Formation in the Qaidam Basin,Inner Asia and orbital forced evolution of lakes during The Pliocene

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Research in Cold and Arid Regions 2023年第5期15卷 239-252页

作者： DunZhu JiaoBa MingZhen Zhang GuoLong liu JianGuo Hui ShaoHua lin aijing li Jing Zhang Jing Peng YiQiao Fu Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Science Beijing 100049China Key Laboratory of Petroleum Resources Gansu ProvinceLanzhouGansu 730000China Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhouGansu 730000China

The Qaidam Basin,as the largest inland basin within the Tibetan Plateau,has accumulated more than 10,000 m of Cenozoic continental *** serves as a crucial research area for documenting Cenozoic climate changes and plateau uplift processes in the Asian ***,the basin holds vast reserves of oil and gas resources,making high-resolution drilling data invaluable for studying *** this study,the longsequence lacustrine deposits of JS1 drill core across the Shizigou Formation in the Yiliping Depression at the western center of the basin were studied,aiming to establish an astronomical timescale for the Shizigou Formation and investigate the characteristics of paleoclimatic changes during the late Miocene to the Pliocene for the Asian *** analysis was carried out using high-resolution natural gamma ray(GR)data sequences,employing techniques such as spectral analysis,filtering,and wavelet analysis in *** results indicated the presence of a stable Milankovitch orbital signal was perfectly recorded in the Shizigou Formation,primarily influenced by eccentricity cycles,with weaker obliquity and precession *** the stable and continuous 405 ka eccentricity cycle in astronomical tuning,a"floating"astronomical timescale with a duration of 6.1 Ma for the Yiliping depression's Shizigou Formation has been *** reference to previously established stratigraphic age anchor points,an absolute astronomical timescale(2.5–8.6 Ma)has been ultimately provided for the Shizigou ***,a clear 100 ka short eccentricity cycle record has been identified during the Pliocene(5.3–2.5 Ma),which corresponds in time with the aridification within the basin during this Pliocene *** addition,a comparison of the Pliocene natural gamma ray curve of the Qaidam Basin with global ice volume variations indicated that the basin's aridification was influenced by global cooling,with eccentricity-modulated prec

关键词： Qaidam basin Shizigou Formation Astronomical time scale Astronomical tuning~100 ka orbital eccentricity

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Exploration of Multi-Dimensional Collaborative Practice and Education Path for Electrical Engineering and Automation Major under the Background of“Dual Carbon”

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Journal of Contemporary Educational Research 2024年第12期8卷 217-229页

作者： Guangming li Qilong Zhang aijing li Yegui Zhang Chang Ji Kun Zhu Junjie Feng School of Physics and Electronics Science Liupanshui Normal UniversityLiupanshui 553004Guizhou ProvinceChina School of Chemistry and Materials Engineering Liupanshui Normal UniversityLiupanshui 553004Guizhou ProvinceChina

Driven by the strategic goal of“dual carbon,”the electric power industry is entering a critical period of transformation and upgrading,and there is a growing demand for composite and applied talents who are both proficient in professional technology and good at *** the electrical engineering and automation major of liupanshui Normal University as an example,this study addresses existing challenges in current talent cultivation *** emphasizing the deep integration of theory and practice and aligning closely with industry needs,the study aims to ensure that the talent cultivation system is both forward-looking and *** on key aspects such as the practical teaching system,practice platforms,teaching content,instructional methods,assessment and evaluation strategies,and resource optimization,a series of targeted measures are *** measures aim to construct a comprehensive,multi-dimensional practice education system that enhances students’practical innovation abilities and overall *** approach not only improves the quality of talent cultivation but also serves as a valuable reference for the development of electrical engineering education in similar local colleges and universities.

关键词： Dual carbon goals Industry demand Composite applied talents Practical education Reform and innovation

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Cellular and Molecular Damage by Ganaxolide on Phanerochaete Chrysosporium

Cellular and Molecular Damage by Ganaxolide on Phanerochaete...

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作者： Hongxia Xiong Changbing liu aijing li Yu lin Wei Huang Tianjin Research Institute for Water Transport Engineering Key Laboratory of Environmental Protection in Water transport EngineeringMinistry of Transport

Galaxolide(1, 3, 4, 6, 7, 8-hexahydro-4, 6, 6, 7, 8,8-hexamethyl-cyclopenta-γ-2-benzopyran, HHCB) is recognized as a novel contaminant in water and has potential adverse impacts on aquatic organisms. The toxic effect of HHCB on Phanerochaete chrysosporium was investigated by exposure of the fungus in nitrogen-limited culture medium to various concentrations of HHCB. The cultivation results showed that both the size and the quantity of the mycelial pellets of P. chrysosporium could be reduced when the concentration of HHCB was higher than 300 mg/L. DNA damage of *** by HHCB was also detected. Comparing with that in the control, the percent polymorphism under different concentrations of HHCB increased, from 21.4% to 42.9%. In addition, the result of UPGMA(un-weighted pair group method of arithmetic means) dendrogram showed that the Simple Matching Coefficient(SM) was decreased with an increase in the concentrations of HHCB. Thus, as an environmental pollutant, HHCB has the toxic effect on P. chrysosporium at both cellular and molecular level.

关键词： AFLP Phanerochaete chrysosporium HHCB DNA damaging effects

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河南师范大学校园鸟类调查

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河南师范大学学报（自然科学版） 2021年第1期49卷 70-79页

作者：李爱景河南师范大学生命科学学院河南新乡453007

从2017年1月至2020年1月对河南师范大学校园鸟类进行了调查,并与国内其他高校校园鸟类进行了比较.共调查到鸟类118种,隶属于15目41科.其中,雀形目鸟类最多,有25科74种,占总种数的63.3%;属于古北界的鸟类有57种,占总数的48%,东洋界的种... 详细信息

从2017年1月至2020年1月对河南师范大学校园鸟类进行了调查,并与国内其他高校校园鸟类进行了比较.共调查到鸟类118种,隶属于15目41科.其中,雀形目鸟类最多,有25科74种,占总种数的63.3%;属于古北界的鸟类有57种,占总数的48%,东洋界的种类27种,占总数的23%,广布种34种,占总数的29%;留鸟41种,占总数的35%,夏候鸟24种,占总数的20%,冬候鸟12种,占总数的10%,旅鸟41种,占总数的35%;有国家二级保护鸟类5种,河南省重点保护鸟类3种,中国特有鸟类4种,列入IUCN极危1种、近危1种;校园鸟类种类总数位居全国高校第二位,每公顷种类密度约为1.04种;校园建设应配置多样化的植被类群、构建包括水域在内的异质化生态环境,从而增加校园的鸟类多样性.

关键词：河南师范大学校园鸟类调查

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