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Fine classification of rice paddy using multitemporal compact polarimetric SAR C band data based on machine learning methods

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Frontiers of Earth Science 2024年第1期18卷 30-43页

作者： Xianyu GUO Junjun YIN kun li jian yang Huimin ZOU Fukun yang School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China

Rice is an important food crop for human *** distinguishing different varieties and sowing methods of rice on a large scale can provide more accurate information for rice growth monitoring,yield estimation,and phenological monitoring,which has significance for the development of modern *** polarimetric(CP)synthetic aperture radar(SAR)provides multichannel information and shows great potential for rice monitoring and ***,the use of machine learning methods to build classification models is a controversial *** this paper,the advantages of CP SAR data,the powerful learning ability of machine learning,and the important factors of the rice growth cycle were taken into account to achieve high-precision and fine classification of rice ***,CP SAR data were simulated by using the seven temporal RADARSAT-2 C-band data ***,20-two CP SAR parameters were extracted from each of the seven temporal CP SAR data *** addition,we fully considered the change degree of CP SAR parameters on a time scale(ΔCP_(DoY)).Six machine learning methods were employed to carry out the fine classification of rice *** results show that the classification methods of machine learning based on multitemporal CP SAR data can obtain better results in the fine classification of rice paddies by considering the parameters ofΔCP_(DoY).The overall accuracy is greater than 95.05%,and the Kappa coefficient is greater than *** them,the random forest(RF)and support vector machine(SVM)achieve the best results,with an overall accuracy reaching 97.32%and 97.37%,respectively,and Kappa coefficient values reaching 0.965 and 0.966,*** the two types of rice paddies,the average accuracy of the transplant hybrid(T-H)rice paddy is greater than 90.64%,and the highest accuracy is 95.95%.The average accuracy of direct-sown japonica(D-J)rice paddy is greater than 92.57%,and the highest accuracy is 96.13%.

关键词： compact polarimetric(CP)SAR rice paddy machine learning fine classification multitemporal

Supported carbon dots decorated with metallothionein for selective cadmium adsorption and removal

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Chinese Chemical Letters 2015年第12期26卷 1496-1501页

作者： Ting yang Yi-kun li Ming-li Chen jian-Hua Wang Research Center for Analytical Sciences College of Sciences Northeastern University

Carbon dots are prepared and immobilized onto spherical SiO_2 through a one-step thermal oxidation and then decorated with metallothionein（MT）, a protein with high affinity towards thiophilic metals. The MT-carbon dots composites are characterized by means of FT-IR, SEM and TGA, giving rise to a MT loading amount of 823 μg g^（-1）. The adsorption of cadmium by the composites is a fast process and follows Langmuir model. In comparison with native SiO_2, a 2- and 2.4-folds improvement on the static and dynamic adsorption capacity of the composites for cadmium are obtained, respectively. Moreover,the adsorption efficiency is not affected by the presence of other metals. Finally, the composites are successfully applied for the removal of cadmium in a series of environmental water samples.

关键词： cadmium adsorbent spherical kinetics isotherms sorption breakthrough effluent alkaline sequential

Altered metabolism of bile acids correlates with clinical parameters and the gut microbiota in patients with diarrhea-predominant irritable bowel syndrome

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World Journal of Gastroenterology 2020年第45期26卷 7153-7172页

作者： Wei Wei Hui-Fen Wang Yu Zhang yan-li Zhang bing-Yu Niu Shu-kun Yao Graduate School Peking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China Department of Gastroenterology China-Japan Friendship HospitalBeijing 100029China Graduate School Beijing University of Chinese MedicineBeijing 100029China

BACKGROUND Bile acids(BAs)have attracted attention in the research of irritable bowel syndrome with predominant diarrhea(IBS-D)due to their ability to modulate bowel function and their tight connection with the gut *** composition of the fecal BA pool in IBS-D patients is reportedly different from that in healthy *** hypothesized that BAs may participate in the pathogenesis of IBS-D and the altered BA profile may be correlated with the gut *** To investigate the role of BAs in the pathogenesis of IBS-D and the correlation between fecal BAs and gut *** Fifty-five IBS-D patients diagnosed according to the Rome Ⅳ criteria and twentyeight age-,sex-,and body mass index-matched healthy controls(HCs)were enrolled in this study at the gastroenterology department of China-Japan Friendship ***,clinical manifestations were assessed with standardized questionnaires,and visceral sensitivity was evaluated via the rectal distension test using a high-resolution manometry *** primary BAs including cholic acid(CA)and chenodeoxycholic acid(CDCA),secondary BAs including deoxycholic acid(DCA),lithocholic acid(LCA),and ursodeoxycholic acid(UDCA)as well as the corresponding tauro-and glyco-BAs were examined by ultraperformance liquid chromatography coupled to tandem mass *** gut microbiota was analyzed using 16S rRNA gene *** between fecal BAs with clinical features and gut microbiota were *** Fecal CA(IBS-D:3037.66[282.82,6917.47]nmol/g,HC:20.19[5.03,1304.28]nmol/g;P<0.001)and CDCA(IBS-D:1721.86[352.80,2613.83]nmol/g,HC:57.16[13.76,1639.92]nmol/g;P<0.001)were significantly increased,while LCA(IBSD:1621.65[58.99,2396.49]nmol/g,HC:2339.24[1737.09,2782.40];P=0.002)and UDCA(IBS-D:8.92[2.33,23.93]nmol/g,HC:17.21[8.76,33.48]nmol/g;P=0.025)were significantly decreased in IBS-D patients compared to *** frequency was positively associated with CA(r=0.294,P=0.030)and CDCA(r=

关键词： Bile acids Irritable bowel syndrome Diarrhea Visceral hypersensitivity Microbiota Dysbiosis

Longer duration of initial invasive mechanical ventilation is still a crucial risk factor for moderate‑to‑severe bronchopulmonary dysplasia in very preterm infants:a multicentrer prospective study

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World Journal of Pediatrics 2023年第6期19卷 577-585页

作者： Cong Dou Yong-Hui Yu Qing-Cui Zhuo jian-Hong Qi Lei Huang yan-Jie Ding De-Juan yang li li Dan li Xiao-Kang Wang yan Wang Xin Qiao Xiang Zhang bing-Jin Zhang Hai-yan jiang Zhong-liang li Simmy Reddy Department of Neonatology Maternal and Child Health Care Hospital of Shandong ProvinceShandong UniversityJinan 250014China Department of Neonatology Shandong Provincial Hospital affiliated to Shandong First Medical UniversityHuaiYin DistrictNo.324Jingwu RoadJinan 250021China Department of Neonatology Shandong Provincial HospitalShandong UniversityHuaiYin DistrictNo.324Jingwu RoadJinan 250021China Department of Neonatology Qilu Hospital of Shandong UniversityJinan 250012China Department of Neonatology Shandong Provincial Maternal and Child Health Care HospitalJinan 250014China Department of Neonatology Yantai Yuhuangding HospitalYantai 264000China Department of Neonatology The First Affiliated Hospital of Shandong First Medical UniversityJinan 250014China Department of Neonatology Linyi People’s HospitalLinyi 276000China Department of Neonatology Liaocheng People’s HospitalLiaocheng 252000China Department of Neonatology The Affiliated Taian City Central Hospital of Qingdao UniversityTaian 271000China Department of Neonatology Jinan Maternity and Child Healthcare HospitalJinan 250001China Department of Neonatology Hebei Petro China Central HospitalLangfang 065000China Department of Neonatology Shengli Olifield Central HospitalDongying 257000China Department of Neonatology The Third Hospital of Baogang GroupBaotou 014000China Department of Neonatology W.F.Maternal and Child Health HospitalWeifang 261011China Cheeloo College of Medicine Shandong UniversityJinan 250000China

Objectives We aimed to evaluate the risk factors for moderate-to-severe bronchopulmonary dysplasia(BPD)and focus on discussing its relationship with the duration of initial invasive mechanical ventilation(IMV)in very preterm neonates less than 32 weeks of gestational age(GA).Methods We performed a prospective cohort study involving infants born at 23–31 weeks of GA who were admitted to 47 different neonatal intensive care unit(NICU)hospitals in China from January 2018 to December *** data were obtained from the Sina-northern Neonatal Network(SNN)*** We identified 6538 very preterm infants,of whom 49.5%(3236/6538)received initial IMV support,and 12.6%(823/6538)were diagnosed with moderate-to-severe BPD *** median duration of initial IMV in the moderateto-severe BPD group was 26(17–41)days,while in the no or mild BPD group,it was 6(3–10)*** incidence rate of moderate-to-severe BPD and the median duration of initial IMV were quite different across different *** logistic regression analysis showed that the onset of moderate-to-severe BPD was significantly associated with the duration of initial IMV[adjusted odds ratio(AOR):1.97;95%confidence interval(CI):1.10–2.67],late-onset neonatal sepsis(LONS),and patent ductus arteriosus(PDA).Conclusion In this multicenter cohort study,the duration of initial IMV was still relatively long in very premature infants,and the longer duration of initial IMV accounts for the increased risk of moderate-to-severe BPD.

关键词： Bronchopulmonary dysplasia Invasive mechanical ventilation Multicenter cohort-Preterm infants Prospective

Protective effects of non-mitogenic human acidic fibroblast growth factor on hydrogen peroxide-induced damage to cardiomyocytes in vitro

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World Journal of Gastroenterology 2005年第35期11卷 5492-5497页

作者： Zhuo-Feng lin Xiao-kun li Yuan lin Fan Wu li-Min liang Xiao-bing Fu Department of Rheumatology the Third AffiliatedHospital of Sun Yat-Sen University Guangzhou 510630 GuangzhouProvince China Department ofBiopharmacy Pharmacy College Jinan University Guangzhou510632 Guangdong Province China Department of Ophthalmology the First AffiliatedHospital of Medical College Jinan University Guangzhou 510632Guangdong Province China Daan Gene Diagnosis Center of Sun Yat-Sen University Guangzhou 510089 Guangdong Province China Wound Healing and Cell Biology Laboratory Institution of Bums 304 Hospital Trauma Center of PostgraduateMedical College Beijing 100037 China

AIM： To study the protective effect of non-mitogenic human acidic fibroblast growth factor （FGF） on cardiac oxidative injury in vivo. METHODS： Ventricular cardiomyocytes were isolated from 1- to 3-d-old neonatal SD mice and cultured in Dulbecco＇s minimum essential medium supplemented with 15% fetal bovine serum under an atmosphere of 50 mL/L CO2-95% air at 37℃, as well as assessed by immunooltochemical assay. We constructed the cardiomyoolte injury model by exposure to a certain concentration of H2O2. Cellular viability, superoxide dismutase （SOD） activity, leakage of maleic dialdehyde and anti-apoptosis effect were included to evaluate the cardiac protective effect of non-mitogenic human acidic FGF. RESULTS： Over 50% of the cardiomyocytes beat spontaneously on the 2nd d of culture and synchronously beat after being cultured for 3 d. Forty-eight hours after plating was completed, the purity of such cultures was 95% myocytes, assessed by an immunocytochemical assay. Cellular viability dramatically decreased with the increasing of the concentration of H2O2. Non-mitogenic human acidic FGF showed significant resistance to thetoxic effect of H2O2, significantly increased the cellular viability as well as the activity of SOD, and dramatically decreased the leakage of maleic dialdehyde as well as the cellular apoptosis rate. CONCLUSION： Hydrogen peroxide shows strong cytotoxicity to the cultured cardiac myocytes, and non-mitogenic human acidic FGF shows strong cardio-protective effect when exposed to a certain concentration of H2O2.

关键词： Non-mitogenic human acidic fibroblast growthfactor Cardioprotection Cardiomyooltes H2O2

Short text classification based on strong feature thesaurus

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第9期13卷 649-659页

作者： bing-kun WANG Yong-feng HUANG Wan-xia yang Xing li Information Cognitive and Intelligent System Research Institute Department of Electronic and EngineeringTsinghua UniversityBeijing 100084China Information Technology National Laboratory Tsinghua UniversityBeijing 100084China

Data sparseness, the evident characteristic of short text, has always been regarded as the main cause of the low ac- curacy in the classification of short texts using statistical methods. Intensive research has been conducted in this area during the past decade. However, most researchers failed to notice that ignoring the semantic importance of certain feature terms might also contribute to low classification accuracy. In this paper we present a new method to tackle the problem by building a strong feature thesaurus （SFT） based on latent Dirichlet allocation （LDA） and information gain （IG） models. By giving larger weights to feature terms in SFT, the classification accuracy can be improved. Specifically, our method appeared to be more effective with more detailed classification. Experiments in two short text datasets demonstrate that our approach achieved improvement compared with the state-of-the-art methods including support vector machine （SVM） and Naive Bayes Multinomial.

关键词： Short text Classification Data sparseness Semantic Strong feature thesaurus (SFT) Latent Dirichlet allocation(LDA)

Reference genes for quantitative real-time PCR analysis and quantitative expression of P5CS in Agropyron mongolicum under drought stress

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Journal of Integrative Agriculture 2016年第9期15卷 2097-2104页

作者： TIAN Qing-song WANG Shu-yan DU jian-cai WU Zhi-juan li Xiao-quan HAN bing Institute of Grassland Research Chinese Academy of Agricultural Sciences Hohhot 010010 P.R. China gronomy College Inner Mongolia Agricultural University Hohhot 010010 P.R. China College of life Science Inner Mongolia Agricultural University Hohhot 010010 P.R. China

Reference genes, stably expressing in different tissues and cells, are commonly used as the references in expression analysis. Selecting the optimum reference gene is crucial to the success of experiments. In this study, the expression stabilities of nine common reference genes, including ACT2, 18 S r RNA, APRT, EF-1α, RNA POL II, TUBα, TUBβ, GAPDH and TLF of Agropyron mongolicum, were studied under drought condition. Among them, 18 S r RNA was found to be the most optimum reference gene under drought stress by the analyzing of ge Norm and Norm Finder software. Quantitative expression levels of P5 CS using 18 S r RNA as the reference gene, and proline contents under drought stress in A. mongolicum were further operated, and we found the expression level of P5 CS gene and proline content had a significantly positive relationship（R^2=0.7763, P〈0.05）. This study established and validated 18 S r RNA as the reference genes in A. mongolicum under drought stress, providing a powerful tool for the quantitative expression analysis of drought genes in A. mongolicum.

关键词： reference genes quantitative real-time PCR drought stress proline pyrroline-5-carboxylic acid synthetase Agropyron mongolicum

Two-stent strategy for renal artery stenosis with bifurcation lesion

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 561-567页

作者： Hong-bing yan Bin ZHENG Zheng WU jian WANG Han-jun ZHAO li SONG Yun-peng CHI Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

renal artery stenosis(RAS) with a bifurcation lesion is a challenge for interventional *** aim of this study is to summarize our experience in RAS with a bifurcation *** patients with RAS involving bifurcation lesion are *** cases 1 to 3,a single-stent strategy was first ***,these three patients were converted to a two-stent strategy for bailout stent implantation in the side *** cases 4 and 5,a simultaneous kissing stent technique was *** showed that the reference vascular diameter of the main branch was much larger than those of the side *** obvious residual stenosis existed in cases 1 to 3 after stent implantation,no obvious residual stenosis was seen in cases 4 and *** artery duplex sonography was performed in cases 1 through 5 at 6,7,7,8,and 6 months,respectively,after the *** evidence of restenosis or occlusion was *** conclusion,stent implantation with the simultaneous kissing stent technique may result in more simple and more satisfactory immediate angiographic results.

关键词： Peripheral atherosclerotic artery disease Angioplasty Stents renal artery stenosis

Using computational fluid dynamic simulation with Flow-3D to reveal the origin of the mushroom stone in the Xiqiao Mountain of Guangdong, China

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Journal of Mountain Science 2022年第1期19卷 1-15页

作者： li jian-cheng WANG Wei ZHENG yan-ming WEN Xiao-hao FENG Jing SHENG li WANG Chen QIU Ming-kun Department of Geography Hanshan Normal UniversityChaozhou 521041China Geographic School South China Normal UniversityGuangzhou 510631China

Mushroom shaped rocks are not uncommon in nature, but their origin is often misunderstood because they can be formed by different natural forces. A huge mushroom stone in a stream valley of the Xiqiao Mountain of Guangdong,China is widely believed to be formed through the way of stream water erosion. However, the result of the simulation performed with Flow-3 D in this study indicates that the mushroom shape of the rock could not have been sculpted by the flowing water erosion because the simulation result contradicts that of the field investigations:(1) the sediment brought by upstream flowing water tends to be deposited on the leeward side of the flowing water preventing the rock on this side form being eroded, but the narrowest part of the rock bottom is exactly located on this side of the rock and(2) the stream flow should erode the bed sediment and produce high abrasion on the rock surface on the upstream and lateral sides of the rock,respectively, but no abrasion marks are found on the same sides of the rock. Subsequent geological analyses in this study provide evidence that the narrow bottom of the mushroom stone was resulted from chemical and physical weathering happening within the sediment that used to deposit on the lee side of the stone.

关键词： Mushroom Stone Computational fluid dynamics(CFD)model Mineralogical analysis Chemical weathering Xiqiao Mountain happening