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quantification of traffic-induced compaction based on soil and agricultural implement parameters

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International Journal of Agricultural and Biological Engineering 2020年第5期13卷 134-140页

作者： Xianliang Wang Xiangcai Zhang Xiaona Lin Luming Sha Hanyu Yang Zhaoyang Guo Zeyu Chen Rongyan Sun College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000ShandongChina

Vehicle-induced soil compaction occurs when agricultural machinery is working in the fields.The accumulated soil compaction could destroy soil structure and inhibit crop growth.The low degree of visualization of soil compaction has always been an important reason for restricting the development of compaction alleviation technology.Therefore,the main objective of this study was to predict soil compaction based on soil and agricultural implement parameters.The component of soil compaction prediction includes traffic-induced stress transmission evaluation and the quantitative relationship between soil stress and bulk density.The modified FRIDA model was used to elucidate the soil stress propagation,which has been validated by previous studies.The Bailey formula was used to establish the intrinsic relationship between soil stress and bulk density.The soil uniaxial compression test was applied to obtain the parameters of the Bailey formula,and soil samples were prepared with three different levels of water content.After fitting with the Bailey formula,under the condition that the soil moisture contents were 16%,20%,and 24%,the fitting coefficients of soil bulk density were respectively 0.980,0.959,and 0.975,which were close to 1.The results indicated that the Bailey formula could be used to calculate soil bulk density based on the stress conditions of the soil.To verify the practicality of the soil compaction prediction model,a field experiment was carried out in Zhuozhou City,Hebei Province,China.The treatment was set for 1,3,5,7,and 9 times compaction with two different loads of compaction equipment.The results showed that the fit coefficient between the predicted and measured values of soil bulk density was greater than 0.641.The slope of the equation was greater than 0.782,proving that the soil bulk density prediction model based on agricultural implements and soil parameters has a good predictive effect on soil bulk density.The soil compaction evaluation model can provide a theoretical basis to further understand

关键词： soil traffic-induced compaction agricultural implement soil bulk density no-tillage soil structure quantification

quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms

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Journal of Mountain Science 2024年第1期21卷 322-334页

作者： QIN Yanhui MA Haoyuan ZHANG Lele YIN Jinshuai ZHENG Xionghui LI Shuo Department of Civil Engineering Qingdao University of TechnologyQingdao 266520China Department of Geography Qinghai Normal UniversityXining 810008China

The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP.

关键词： Freeze–thaw cycles quantification Machine learning algorithms Qinghai–Tibet Plateau Concrete

Detection and quantification of Water-Soluble Inorganic Chlorine,Bromine and Iodine by MALDI-MS

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Journal of Analysis and Testing 2022年第4期6卷 419-423页

作者： Yi Tong Zheng-Zheng Liu Jia-Feng Lu Hai-Yan Zhang Ke-Qiang Shi Guan-Ru Chen Ya-Qin Liu Hong-Ru Feng Yuan-Jiang Pan Department of Chemistry Zhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Ecological and Environmental Monitoring Forewarning and Quality ControlZhejiang Ecological and Environmental Monitoring CenterHangzhou310012China School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China

Halogens are elements in soil and water that occur as organic and inorganic species.Studies have shown that inorganic halogens are closely related to animal and plant life.Matrix-assisted laser desorption/ionization mass spectrometry(MALDI-MS)can achieve high-throughput and rapid analysis,which is also an essential characteristic in some environmental studies.However,there is currently no report on MALDI-MS analysis for water-soluble inorganic halogen compounds.In this study,we aimed to develop a reliable and reproductive method to detect inorganic halogens in soil and water by MALDI-MS.Based on sinapic acid(SA)and silver trifluoromethanesulfonate(SA/AgOTf)as the matrix in negative-ion mode,MALDI-MS showed excellent MS signals related to halogens.Under the optimum conditions,the method achieved satisfactory linearity(R^(2)>0.99)and repeatability(RSD<18%).The LODs for Cl^(−),Br^(−)and I^(−)were 0.76,0.11 and 0.10μg/mL,respectively.The concentration of inorganic halogens from 24 samples was successfully determined by MALDI-MS.In summary,an innovative method was developed for the analysis of inorganic halogens by MALDI-MS using a novel SA/AgOTf matrix,extending the application of MALDI-MS in inorganic compounds.

关键词： MALDI-MS Water-soluble halogen quantification Soil Water

Real-time quantification of nuclear RNA export using an intracellular relocation probe

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Chinese Chemical Letters 2022年第8期33卷 3865-3868页

作者： Jie Shen Juan Chen Dong Wang Zhengjie Liu Guangmei Han Bianhua Liu Mingyong Han Ruilong Zhang Guodong Liu Zhongping Zhang School of Chemistry and Chemical Engineering Information Materials and Intelligent Sensing Laboratory of Anhui Provinceand Institute of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University) Ministry of EducationHefei 230601China Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China School of Life and Health Sciences Anhui Science and Technology UniversityChuzhou 233100China

Nuclear RNA export into the cytoplasm is one of the key steps in protein expression to realize biological functions.Despite the broad availability of nucleic acid dyes,tracking and quantifying the highly dynamic process of RNA export in live cells is challenging.When dye-labeled RNA enters the cytoplasm,the dye molecules are released upon degradation of the RNA,allowing them to re-enter the cell nucleus.As a result,the ratio between the dye exported with RNA into the cytoplasm and the portion staying inside the nucleus cannot be determined.To address this common limitation,we report the design of a smart probe that can only check into the nucleus once.When adding to cells,this probe rapidly binds with nuclear RNAs in live cells and reacts with intrinsic H_(2)S.This reaction not only activates the fluorescence for RNA tracking but also changes the structure of probe and consequently its intracellular localization.After disassociating from exported RNAs in cytoplasm,the probe preferentially enters lysosomes rather than cell nucleus,enabling real-time quantitative measurement of nuclear RNA exports.Using this probe,we successfully evaluated the effects of hormones and cancer drugs on nuclear RNA export in live cells.Interestingly,we found that hormones inhibiting RNA exports can partially offset the effect of chemotherapy.

关键词： RNA export quantification Relocation probe Fluorescence imaging Hormone

quantification of six bioactive compounds in Zhenqi Fuzheng preparation by high-performance liquid chromatography coupled with diode array detector and evaporative light scattering detector

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Journal of Pharmaceutical Analysis 2011年第1期1卷 20-25页

作者： Yi-Kai Shi Fang Cui Fang-Di Hu Ying-Yan Bi Yu-Feng Ma Shi-Lan Feng School of Pharmacy Lanzhou University Lanzhou 730000 China Gansu Province Key Laboratory of Preclinical Study for New Drugs of Gansu Province Lanzhou 730000 China

A simple and accurate high-performance liquid chromatography（HPLC）coupled with diode array detector（DAD）and evaporative light scattering detector（ELSD）was established for the determination of six bioactive compounds in Zhenqi Fuzheng preparation（ZFP）.The monitoring wavelengths were 254,275 and 328 nm.Under the optimum conditions,good separation was achieved,and the assay was fully validated in respect of precision,repeatability and accuracy.The proposed method was successfully applied to quantify the six ingredients in 31 batches of ZFP samples and evaluate the variation by hierarchical cluster analysis（HCA）,which demonstrated significant variations on the content of these compounds in the samples from different manufacturers with different preparation procedures.The developed HPLC method can be used as a valid analytical method to evaluate the intrinsic quality of this preparation.

关键词： high-performance liquid chromatography（HPLC） diode array detector（DAD） evaporative light scattering detector（ELSD） Zhenqi Fuzheng preparation quantification hierarchical cluster analysis

GC-NICI-MS analysis of acetazolamide and other sulfonamide (R-SO2-NH2)drugs as pentafluorobenzyl derivatives [R-SO2-N(PFB)2] and quantification of pharmacological acetazolamide in human urine

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Journal of Pharmaceutical Analysis 2020年第1期10卷 49-59页

作者： Olga Begou Kathrin Drabert Georgios Theodoridis Dimitrios Tsikas Institute of Toxicology Core Unit ProteomicsHannover Medical SchoolCarl-Neuberg-Strasse 1D-30625HannoverGermany Department of Chemistry Aristotle University of Thessaloniki54124ThessalonikiGreece BIOMIC_AUTh Center for Interdisciplinary Research and Innovation(CIRI-AUTH)Balkan Center10th Km Thessaloniki-Thermi RdP.O.Box 8318GR 57001ThessalonikiGreece

Acetazolamide(molecular mass(MM),222)belongs to the class of sulfonamides(R-SO2-NH2)and is one of the strongest pharmacological inhibitors of carbonic anhydrase activity.Acetazolamide is excreted unchanged in the urine.Here,we report on the development,validation and biomedical application of a stable-isotope dilution GC-MS method for the reliable quantitative determination of acetazolamide in human urine.The method is based on evaporation to dryness of 50 mL urine aliquots,base-catalyzed derivatization of acetazolamide(d0-AZM)and its internal standard[acetylo-2H3]acetazolamide(d3-AZM)in 30 vol%pentafluorobenzyl(PFB)bromide in acetonitrile(60 min,30C),reconstitution in toluene(200 mL)and injection of 1-mL aliquots.The negative-ion chemical ionization(NICI)mass spectra(methane)of the PFB derivatives contained several intense ions including[M]‒at m/z 581 for d0-AZM and m/z 584 for d3-AZM,suggesting derivatization of their sulfonamide groups to form N,N-dipentafluorobenzyl derivatives(R-SO2-N(PFB)2),i.e.,d0-AZM-(PFB)2 and d3-AZM-(PFB)2,respectively.quantification was performed by selected-ion monitoring of m/z 581 and 83 for d0-AZM-(PFB)2 and m/z 584 and 86 for d3-AZM-(PFB)2.The limits of detection and quantitation of the method were determined to be 300 fmol(67 pg)and 1 mM of acetazolamide,respectively.Intra-and inter-assay precision and accuracy for acetazolamide in human urine samples in pharmacologically relevant concentration ranges were determined to be 0.3%e4.2%and 95.3%e109%,respectively.The method was applied to measure urinary acetazolamide excretion after ingestion of a 250 mg acetazolamide-containing tablet(Acemit®)by a healthy volunteer.Among other tested sulfonamide drugs,methazolamide(MM,236)was also found to form a N,N-dipentafluorobenzyl derivative,whereas dorzolamide(MM,324)was hardly detectable.No GC-MS peaks were obtained from the PFB bromide derivatization of hydrochlorothiazide(MM,298),xipamide(MM,355),indapamide and metholazone(MM,366 each)or brinzolamide(MM,384).We demonstrate for the first

关键词： Acetazolamide Derivatization quantification Sulfonamides Validation

CircAST:Full-length Assembly and quantification of Alternatively Spliced Isoforms in Circular RNAs

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Genomics, Proteomics & Bioinformatics 2019年第5期17卷 522-534页

作者： Jing Wu Yan Li Cheng Wang Yiqiang Cui Tianyi Xu Chang Wang Xiao Wang Jiahao Sha Bin Jiang Kai Wang Zhibin Hu Xuejiang Guo Xiaofeng Song Department of Biomedical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Biomedical Engineering and Informatics Nanjing Medical UniversityNanjing 211166China State Key Laboratory of Reproductive Medicine Nanjing Medical UniversityNanjing 211166China Center of Pathology and Clinical Laboratory Sir Run Run HospitalNanjing Medical UniversityNanjing 211166China Center for Cellular and Molecular Therapeutic Children’s Hospital of PhiladelphiaPhiladelphiaPA 19104USA

Circular RNAs(circ RNAs),covalently closed continuous RNA loops,are generated from cognate linear RNAs through back splicing events,and alternative splicing events may generate different circ RNA isoforms at the same locus.However,the challenges of reconstruction and quantification of alternatively spliced full-length circ RNAs remain unresolved.On the basis of the internal structural characteristics of circ RNAs,we developed Circ AST,a tool to assemble alternatively spliced circ RNA transcripts and estimate their expression by using multiple splice graphs.Simulation studies showed that Circ AST correctly assembled the full sequences of circ RNAs with a sensitivity of 85.63%–94.32%and a precision of 81.96%–87.55%.By assigning reads to specific isoforms,Circ AST quantified the expression of circ RNA isoforms with correlation coefficients of 0.85–0.99 between theoretical and estimated values.We evaluated Circ AST on an in-house mouse testis RNA-seq dataset with RNase R treatment for enriching circ RNAs and identified 380 circ RNAs with full-length sequences different from those of their corresponding cognate linear RNAs.RT-PCR and Sanger sequencing analyses validated 32 out of 37 randomly selected isoforms,thus further indicating the good performance of Circ AST,especially for isoforms with low abundance.We also applied Circ AST to published experimental data and observed substantial diversity in circular transcripts across samples,thus suggesting that circ RNA expression is highly regulated.Circ AST can be accessed freely at https://***/xiaofengsong/CircAST.

关键词： Circular RNA Full-length reconstruction Isoform quantification Multiple splice graph model Transcriptome

Development of a fast and precise method for simultaneous quantification of the PLGA monomers lactic and glycolic acid by HPLC

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Journal of Pharmaceutical Analysis 2019年第2期9卷 100-107页

作者： Marcel Pourasghar Aljoscha Koenneke Peter Meiers Marc Schneider Department of Pharmacy Biopharmaceutics and Pharmaceutical TechnologySaarland University

Poly(lactide-co-glycolide acid)(PLGA) is an extraordinary well-described polymer and has excellent pharmaceutical properties like high biocompatibility and good biodegradability. Hence, it is one of the most used materials for drug delivery and biomedical systems, also being present in several US Food and Drug Administration-approved carrier systems and therapeutic devices. For both applications, the quantification of the polymer is inalienable. During the development of a production process, parameters like yield or loading efficacy are essential to be determined. Although PLGA is a well-defined biomaterial,it still lacks a sensitive and convenient quantification approach for PLGA-based systems. Thus, we present a novel method for the fast and precise quantification of PLGA by RP-HPLC. The polymer is hydrolyzed into its monomers, glycolic acid and lactic acid. Afterwards, the monomers are derivatized with the absorption-enhancing molecule 2,4′-dibromoacetophenone. Furthermore, the wavelength of the derivatized monomers is shifted to higher wavelengths, where the used solvents show a lower absorption,increasing the sensitivity and detectability. The developed method has a detection limit of 0.1 mg/mL,enabling the quantification of low amounts of PLGA. By quantifying both monomers separately, information about the PLGA monomer ratio can be also directly obtained, being relevant for degradation behavior. Compared to existing approaches, like gravimetric or nuclear magnetic resonance measurements, which are tedious or expensive, the developed method is fast, ideal for routine screening, and it is selective since no stabilizer or excipient is interfering. Due to the high sensitivity and rapidity of the method, it is suitable for both laboratory and industrial uses.

关键词： Poly(lactide-co-glycolide acid)(PLGA) Alkaline hydrolysis quantification Drug delivery system RP-HPLC

QuaPra: Efficient transcript assembly and quantification using quadratic programming with Apriori algorithm

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Science China(Life Sciences) 2019年第7期62卷 937-946页

作者： Xiangjun Ji Weida Tong Baitang Ning Christopher E. Mason David P. Kreil Pawel P. Labaj Geng Chen Tieliu Shi The Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory BiologyInstitute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China National Center for Toxicological Research U.S. Food and Drug Administration3900 NCTR RDJefferson AR 72079USA Department of Physiology and Biophysics Weill Cornell MedicineNew York 10065USA The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine New York 10021USA Feil Family Brain & Mind Research Institute New York 10065USA Chair of Bioinformatics Research Group Boku UniversityVienna A-1190Austria Malopolska Centre of Biotechnology Jagiellonian UniversityKrakow 30-387Poland APART Fellow Austrian Academy of ScienceVienna A-1190Austria National Center for International Research of Biological Targeting Diagnosis and Therapy Guangxi Key Laboratory of Biological Targeting Diagnosis and Therapy ResearchCollaborative Innovation Center for Targeting Tumor Diagnosis and TherapyGuangxi Medical UniversityNanning 530021China

RNA sequencing(RNA-seq) has greatly facilitated the exploring of transcriptome landscape for diverse organisms.However,transcriptome reconstruction is still challenging due to various limitations of current tools and sequencing technologies.Here,we introduce an efficient tool,QuaPra(Quadratic Programming combined with Apriori),for accurate transcriptome assembly and quantification.QuaPra could detect at least 26.5% more low abundance(0.1–1 FPKM) transcripts with over 2.7% increase of sensitivity and precision on simulated data compared to other currently popular tools.Moreover,around one-quarter more known transcripts were correctly assembled by QuaPra than other assemblers on real sequencing data.QuaPra is freely available at http://***/QuaPra/.

关键词： RNA-Seq transcriptome reconstruction transcript assembly transcript quantification