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Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques

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Journal of Mountain Science 2024年第2期21卷 397-412页

作者： ZHAO Haijun wei aihua MA Fengshan DAI Fenggang JIANG Yongbing LI Hui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Hebei Province Key Laboratory of Sustained Utilization&Development of Water Recourse Hebei GEO UniversityShijiazhuang 050031China School of Water Resources and Environment Hebei GEO UniversityShijiazhuang 050031China The Sixth Geological Brigade of Geological Mineral Exploration and Development Bureau of Hebei Province Shijiazhuang 050085China

The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility *** this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning *** total,133 historical debris flow records and 16 related factors were *** support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step ***,the particle swarm optimization(PSO)algorithm was employed to select the SVM model ***,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,*** statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the *** results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM ***,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing *** was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment ***,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning *** high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intens

关键词： Chengde Feature selection Support vector machine Particle swarm optimization Principal component analysis Debris flow susceptibility

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Hydrochemical Characteristics and the Suitability of Groundwater in the Coastal Region of Tangshan, China

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Journal of Earth Science 2014年第6期25卷 1067-1075页

作者： Fengshan Ma aihua wei~* Qinghai Deng Haijun Zhao Key Laboratory of Engineering Geomechanics Institute of Geology and Geophysics Chinese Academy of Sciences Shijiazhuang University of Economics Hebei Province Key Laboratory of Sustained Utilization and Development of Water Resources College of Geological Science and Engineering Shandong University of Science and Technology

Through collecting groundwater samples from the coastal region of Tangshan, China, the hydrochemical processes that affect the chemical composition of groundwater and the quality of resources were analyzed. Chemical constituents, factor analysis, and a graphic method were employed in this research. The results show that human activities obviously affect fresh groundwater. The deep groundwater distributed in the southern part of the region is severely affected by salinization, and the shallow groundwater in the north is also beginning to show the same deterioration. The chemical concentrations of the deep groundwater depend largely upon the water-rock interaction, the mixing of saline water and the ion exchange processes. With the exception of sample C-33, all the groundwater samples in the study area are suitable for drinking. Tests show that roughly half of the deep groundwater samples have at least one water quality index indicating that it is chemically doubtful or unsuitable for irrigation. Therefore, it is concluded that deep groundwater is becoming an unacceptable resource to irrigate areas located near the coastline because the groundwater quality in the study area is exhibiting signs of degradation. This study＇s findings contribute to a better understanding of groundwater resources in order to support regional management and protection.

关键词： groundwater factor analysis ion exchange process salinization water quality index

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The Characteristics and Causes of Land Subsidence in Tanggu Based on the GPS Survey System and Numerical Simulation

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1495-1507页

作者： MA Fengshan wei aihua HAN Zhantao ZHAO Haijun GUO Jie Key Laboratory of Engineering Geomechanics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China The Institute ofHydrogeology andEnvironmental Geology Chinese Academy of Geological Sciences Shijiazhuang 050061 China

Land subsidence is a severe hazard threatening Tanggu, a flat lowland area, and evidences of land subsidence can be seen throughout the city. A new reasonable GPS network was set up in this area from 2008 to 2010. The monitoring data show that land subsidence was serious and two main subsidence cones were obviously formed in the region. One emerged at Hujiayuan, with the maximum rate reaching 60 ram/a, and the influence region enlarged prominently from 2005 to 2010. The other one occurred at Kaifaqu, which became obvious only after 2005, and it showed a decreasing tendency with time. To analyze the causes of ground settlement, a correlation between groundwater withdrawal and land subsidence was firstly made. The results confirmed that over-exploitation of groundwater was the major cause for the severe settlement in Hujiayuan. Meanwhile, the subsidence of Kaifaqu was also related to groundwater withdrawal before 2005. However, the relationship became unconspicuous after 2005. To find the cause of this abnormity, a three-dimensional finite element numerical model, coupled with groundwater flow and subsidence, was built. The simulation results indicate that the subsidence induced by high-rise buildings is serious, but the affected range is limited and it also shows a decreasing trend with time, corresponding to the subsidence characteristics at Kaifaqu. Therefore, more attention should be paid to this hazard induced by engineering construction besides groundwater withdrawal, as more high-rise buildings are under construction in Tanggu.

关键词： land subsidence GPS subsidence cones finite element numerical model high-rise buildings

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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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Journal of Mountain Science 2024年第1期21卷 146-159页

作者： HAO aihua LUO Zhengming CHEN Xiaojiang Department of Geography Xinzhou Normal UniversityXinzhou 034000China Department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(Pweiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

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高校重点学科文献需求及资源保障分析研究——以山西大学哲学学科为例

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长治学院学报 2024年第4期41卷 92-97页

作者：魏爱华贾玲玲卫雯李东旺山西大学图书馆山西太原030006

哲学是山西大学双一流建设学科之一。文章以2013-2022年中国知网数据库收录山西大学哲学学科期刊论文、博硕士论文引文为样本,通过数据统计、分析,充分了解哲学学科发展所需文献的语种、年代等,用数据真实反映各文献类型的需求及满足情... 详细信息

哲学是山西大学双一流建设学科之一。文章以2013-2022年中国知网数据库收录山西大学哲学学科期刊论文、博硕士论文引文为样本,通过数据统计、分析,充分了解哲学学科发展所需文献的语种、年代等,用数据真实反映各文献类型的需求及满足情况。最后从用户实际需求角度为该校今后哲学学科资源保障及资源建设提出了合理化建议。

关键词：重点学科文献需求资源保障学科资源建设

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Honeycomb-like biochar framework coupled with Fe_(3)O_(4)/FeS nanoparticles as efficient heterogeneous Fenton catalyst for phenol degradation

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Journal of Environmental Sciences 2024年第2期136卷 390-399页

作者： aihua Cheng Yi He Xiaohe Liu Chi He Department of Environmental Engineering College of Geology and EnvironmentXi’an University of Science and TechnologyXi’an 710054China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an 710049China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China

Achieving an efficient and stable heterogeneous Fenton reaction over a wide pH range is of great significance for wastewater ***,a pollen-derived biochar catalyst with a unique honeycomb-like structure,coupled with the dispersion of magnetic Fe_(3)O_(4)/FeS(Fe/S)nanoparticles,was synthesized by simple impregnation precursor,followed by *** prepared Fe/S-biochar catalyst demonstrated outstanding phenol degradation efficiency across a wide pH range,with 98%of which eliminated even under neutral conditions(pH 7.0).The high catalytic activity was due to the multilevel porous structure of pollenderived biochar provided enough active sites and allowed for better electron transfer,then increases oxidation ability to promote the ***,the acid microenvironment formed by SO_(4)^(2-)group from Fe/S composite extended the pH range for Fenton reaction,and S^(2-)facilitated the conversion of≡Fe^(3+)to≡Fe^(2+),resulting in remarkable degradation ***,biochar can effectively promote cycling stability by limiting Fe *** work may provide a general strategy for designing 3D framework biochar-based Fe/S catalysts with excellent performance for heterogeneous Fenton reactions.

关键词： Biomass Biochar Fenton reaction Fe_(3)O_(4)/FeS(Fe/S) Phenol degradation

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Clinical feature and waveform in infantile nystagmus syndrome in children with FRMD7 gene mutations

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Science China(Life Sciences) 2017年第7期60卷 707-713页

作者： Dayong Bai wei Shi Zhan Qi wei Li aihua wei~* Yanhui Cui Cheng Li Li Li Department of Ophthalmology Beijing Children's Hospital Capital Medical UniversityNational Center for Children's Health Beijing Pediatric Research Institute Beijing Children's Hospital Capital Medical UniversityNational Center for Children's Health Department of Dermatology Beijing Tongren Hospital Capital Medical University

Infant nystagmus sydrome presents as involuntary eye movement disorder and can affect seriously ocular function. We performed a retrospective study of clinical data and FRMD7 genetic test results in 12 cases of infantile nystagmus syndrome to correlate waveform, stereopsis, and visual acuity. The patients(age 6.40±2.67 years) had FRMD7 mutations as follows: missense in eight cases, shear in two cases, frameshift in one case, and non-frameshift in one case. Horizontal jerk waveform was observed in six cases, versus horizontal pendulum in five cases and dual jerk in one case. The uncorrected visual acuity(24 eyes) was 0.21±0.12,compared with a corrected visual acuity(24 eyes) of 0.32±0.14. All patients had simultaneous perception, versus fusion function in 10 cases(83.33%) and stereoscopic vision in seven cases(58.33%) using the synoptophore. Eleven cases(91.67%) detected the stereo fly, compared with five cases(41.67%) for stereoscopic circles and seven cases(58.33%) for stereoscopic animals by Titmus test. Stereoscopic vision using the synoptophore did not correlate with the frequency, amplitude, or intensity of nystagmus or with corrected binocular visual acuity. The infantile nystagmus syndrome with FRMD7 mutations in our cases was caused primarily de novo and missense mutations. Visual acuity and binocular visual function were significant impaired, and the waveform was generally horizontal jerk. Also, an infrared videonystagmogram can record the frequency, amplitude, and intensity of nystagmus accurately.

关键词： infantile nystagmus FRMD7 gene mutation waveform vision stereopsis

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Quantitative assessment of the breast cancer marker HER2 using a gold nanoparticle-based lateral flow immunoassay

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Nano Research 2024年第6期17卷 5452-5460页

作者： Liya Ye Xinxin Xu aihua Qu Liqiang Liu Chuanlai Xu Hua Kuang International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and TechnologyJiangnan UniversityWuxi 214122China

Human epidermal growth factor receptor 2(HER2)is an important biomarker for detection and treatment of breast *** this study,we developed monoclonal antibodies against the extracellular domain(ECD)of HER2 and established a rapid and accurate lateral flow immunoassay(LFIA)for use in community medical *** gene sequence of human HER2-ECD was obtained from the National Center for Biotechnology Information(NCBI)to construct the expression ***2-ECD protein expressed in HEK293F cells was used to immunize BALB/c *** monoclonal antibodies were produced in mouse ascites and isolated by hybridoma cell *** were analyzed for purity by SDS-PAGE(sodium dodecyl sulphate-polyacrylamide gel-electrophoresis)and affinity was assessed by enzyme-linked immunosorbent assay(ELISA)while subtypes were detected using the commercial *** HER2-ECD test strip was prepared based on the sandwich method and evaluated using a portable detection *** affinity of the paired antibodies,4D8 and 8D9,both reached 1×108 L/*** antibodies specifically recognized the HER2-ECD protein in *** limit of detection(LOD)of the gold nanoparticle(AuNP)-based LFIA was 1.7 ng/mL with a detection range of 1.7-400 ng/mL,and the performance of the HER2-ECD strip correlated well with that of a Siemens chemiluminescent immunoassay(CLIA)*** conclusion,the paired antibodies were successfully prepared with high affinity and *** AuNP-based LFIA of HER2-ECD provides a fast and accurate method to detect the concentration of HER2-ECD in serum samples for clinical use in community medical institutions,and could contribute to determining the progress of the disease or the effectiveness of treatment.

关键词： human epidermal growth factor receptor 2 breast cancer monoclonal antibody quantitative lateral flow immunoassay

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Electron vortex generations in photoionization of hydrogen atoms by circularly-polarized chirped attosecond pulses

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Communications in Theoretical Physics 2024年第1期76卷 111-118页

作者： Bingshuang Zhang Xiaoyu Liu Fengzheng Zhu Liguang Jiao aihua Liu Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China College of Physics Jilin UniversityChangchun 130012China Helmholtz-Institut Jena D-07743 JenaGermany State Key Laboratory of Transient Optics and Photonics Chinese Academy of SciencesXi'an 710119China

By numerically solving the time-dependent Schr?dinger equation and employing the analytical perturbative model,we investigated the chirp-induced electron vortex in the photoionization of hydrogen atoms by a pair of counter-rotating circularly polarized chirped attosecond extremely ultraviolet *** demonstrated that single-photon ionization of hydrogen atoms generates photoelectron momentum distributions(PMDs)with distinct helical vortex structures either with or without a time delay between two counter-rotating circularly polarized laser *** structures are highly sensitive to both the time delay between the pulses and their chirp *** analytical model reveals that the splitting of vortex spirals is caused by the sign changing of the chirp-induced frequency-dependent time *** showed that to obtain the counterpart of the PMD under a pair of counter-rotating circularly polarized chirped pulses,both chirp parameters and ordering of pulses need to be reversed.

关键词： photoionization ultrafast processes ultrafast dynamics electron vortex

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A gold-based multiplex immunochromatographic sensor for detecting paclitaxel

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Nano Research 2024年第7期17卷 6420-6429页

作者： Xiaoqian Jiang aihua Qu Xinxin Xu Hua Kuang Liqiang Liu Chuanlai Xu State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and TechnologyJiangnan UniversityWuxi 214122China

Paclitaxel(PTX),methotrexate(MTX),and 5-fluorouracil(5-FU)are commonly-used small molecule anti-tumor drugs for breast ***,drug resistance occurs with long-term treatment or excessive use,and the high concentrations of PTX,MTX,and 5-FU in patients may lead to side effects with dose-limiting toxicities,such as myelosuppression,hepatotoxicity,and peripheral ***,concentration monitoring of PTX,MTX,and 5-FU in clinical treatment is very *** prepared highly sensitive and specific monoclonal antibodies using several haptens,and established a multiple paper-based sensor utilizing optical signals of gold nanoparticles,which simultaneously detected PTX,MTX,and 5-FU in human plasma or urine with 10 min.A portable scanner for quantitative detection in plasma and urine samples was used,and the calculated limit of detection(cLOD)values were 0.002 and 0.142μg/mL for PTX,0.187 and 0.976 ng/mL for MTX,and 0.057 and 0.128μg/mL for 5-FU,*** the recovery test,the recovery rates and the coefficient of variation were 85.84%–108.81%and 1.23%–8.80%,respectively,indicating the reliability and accuracy of the multiple gold immunochromatographic strip(GIS).In addition,for the determination of collected clinical plasma samples,the correlation between the test data of the multiple GIS and liquid chromatography–tandem mass spectrometry(LC–MS/MS)was ***,the developed multiple GIS could be applied to the rapid detection of PTX,MTX,and 5-FU in different clinical samples.

关键词： paclitaxel methotrexate 5-fluorouracil immunochromatographic assay plasma urine

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