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International Journal of Digital Earth 2017年第3期10卷 307-323页

作者： Yanjun Su qin ma qinghua Guo Sierra Nevada Research Institute School of EngineeringUniversity of California at MercedMercedCAUSA State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijingPeople’s Republic of China

Forests of the Sierra Nevada(SN)mountain range are valuable natural heritages for the region and the country,and tree height is an important forest structure parameter for understanding the SN forest *** is still a need in the accurate estimation of wall-to-wall SN tree height distribution at fine spatial *** this study,we presented a method to map wall-to-wall forest tree height(defined as Lorey’s height)across the SN at 70-m resolution by fusing multi-source datasets,including over 1600 in situ tree height measurements and over 1600 km^(2) airborne light detection and ranging(LiDAR)*** tree height estimates within these airborne LiDAR boundaries were first computed based on in situ measurements,and then these airborne LiDAR-derived tree heights were used as reference data to estimate tree heights at Geoscience Laser Altimeter System(GLAS)***,the random forest algorithm was used to model the SN tree height from these GLAS tree heights,optical imagery,topographic data,and climate *** results show that our fine-resolution SN tree height product has a good correspondence with field *** coefficient of determination between them is 0.60,and the root-mean-squared error is 5.45 m.

关键词： Tree height Sierra Nevada LiDAR integration fine resolution

Littlewood Paley g-function on the Heisenberg Group

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Acta mathematica Sinica,English Series 2006年第1期22卷 95-100页

作者： He Ping LIU Rui qin ma LmaM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

We consider the g-function related to a class of radial functions which gives a characterization of the L^p-norm of a function on the Heisenberg group.

关键词： Heisenberg group g-function

Ichthyoplankton recruitment from mainstream of the Changjiang River into the Dongting Lake, the second largest freshwater lake in China

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Journal of Oceanology and Limnology 2019年第3期37卷 1090-1101页

作者： ma qin LI Mingzheng qin Xiangchao LIU Huanzhang CAO Wenxuan Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China Yellow River Basin Water Environment Monitoring Center Zhengzhou 450004China

Floodplains are important and distinctive ecosystems around the world,and the recruitment of ichthyoplankton from river to floodplain lakes is crucial to maintain this unique ***,this process has not been well *** this study,ichthyoplankton were sampled to investigate the details of ichthyoplankton recruitment from the Changjiang(Yangtze)River to the Dongting Lake via a floodway channel,the Songzi River,from may to July in 2013 and *** the study period,41 species of eggs and larvae were *** the samples,16 were river-lake migratory species(RL),representing 23.5%of the species in the Dongting *** 2013,an estimated 130 million eggs and 3180 million larvae drifted through the sampling section,and in 2014,an estimated 1 060 million eggs and 1040 million larvae drifted through the sampling *** amount of eggs and larvae of RL reached 3 210 million in 2013 and 1 850 million in 2014,*** results demonstrated the importance of ichthyoplankton recruitment from the river to the lake,as species diversity will decrease sharply without this *** correspondence analysis(CCA)showed that water temperature and water flow are the two most important factors influencing the spawning activities of *** maintain the high fish diversity in the Changjiang floodplain,we suggest to irrigate the channel to increase water discharge and increase the transport of ichthyoplankton from the Changjiang mainstream into the Dongting Lake.

关键词： ichthyoplankton recruitment Changjiang floodplain Dongting Lake

maleness-on-the-Y(MoY) orthologue is a key regulator of male sex determination in Zeugodacus cucurbitae(Diptera:Tephritidae)

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Journal of Integrative Agriculture 2023年第2期22卷 505-513页

作者： FAN Zi-zhen ma qin ma Si-ya CAO Feng-qin YAN Ri-hui LIN Xian-wu Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests of Ministry of Education Hainan UniversityHaikou 570228P.R.China School of Plant Protection Hainan UniversityHaikou 570228P.R.China School of Life Sciences Hainan UniversityHaikou 570228P.R.China Hainan Yazhou Bay Seed Lab Sanya 572000P.R.China

The initiation of sex differentiation in insects is regulated by primary sex determination *** the Medfly Ceratitis capitata and other tephritids,maleness-on-the-Y(MoY) is the master gene for male sex ***,the primary signal in Zeugodacus cucurbitae(Coquillett),a very destructive tephritid pest across the world,remains *** this study,we have isolated and characterized the Medfly MoY homolog in ***,*** protein shows high sequence conservation to its homologs in Bactrocera *** transcription begins and peaks at very early embryonic stages and then becomes undetectable except the testes and heads of day 1 male *** ZcMoY in early embryos by RNAi causes abnormal external genitalia and interior reproductive organs,giving rise to intersexes and feminization of XY *** expression pattern and knockdown phenotypes of ZcMoY indicate that ZcMoY plays a key role in regulating sex determination of *** *** findings will help the understanding of sex determination in *** and facilitate the development of genetic sexing strains in its biological control.

关键词： MoY Zeugodacus cucurbitae sex determination RNA interference reproductive system

Global Genomic Arrangement of Bacterial Genes Is Closely Tied with the Total Transcriptional Efficiency

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Genomics, Proteomics & Bioinformatics 2013年第1期11卷 66-71页

作者： qin ma Ying Xu Computational Systems Biology Laboratory Department of Biochemistry and Molecular Biology and Institute of BioinformaticsUniversity of Georgia BioEnergy Science Center College of Computer Science and Technology Jilin University

The availability of a large number of sequenced bacterial genomes allows researchers not only to derive functional and regulation information about specific organisms but also to study the fundamental properties of the organization of a genome. Here we address an important and chal- lenging question regarding the global arrangement of operons in a bacterial genome： why operons in a bacterial genome are arranged in the way they are. We have previously studied this question and found that operons of more frequently activated pathways tend to be more clustered together in a genome. Specifically, we have developed a simple sequential distance-based pseudo energy func- tion and found that the arrangement of operons in a bacterial genome tend to minimize the clus- teredness function （C value） in comparison with artificially-generated alternatives, for a variety of bacterial genomes. Here we extend our previous work, and report a number of new observations：（a） operons of the same pathways tend to group into a few clusters rather than one; and （b） the global arrangement of these operon clusters tend to minimize a new ＂energy＂ function （C＋ value） that reflects the efficiency of the transcriptional activation of the encoded pathways. These obser- vations provide insights into further study of the genomic organization of genes in bacteria.

关键词： Global genoic arrangement Bacterial genome Chromosomal supercoils Biological pathways Gene expression

Quantifying individual tree growth and tree competition using bi-temporal airborne laser scanning data:a case study in the Sierra Nevada Mountains,California

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International Journal of Digital Earth 2018年第5期11卷 485-503页

作者： qin ma Yanjun Su Shengli Tao qinghua Guo School of Engineering Sierra Nevada Research InstituteUniversity of California at MercedMercedCAUSA State Key Laboratory of Vegetation and Environmental Change Chinese Academy of SciencesInstitute of BotanyBeijingPeople’s Republic of China Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijingPeople’s Republic of China

Improved monitoring and understanding of tree growth and its responses to controlling factors are important for tree growth *** Laser Scanning(ALS)can be used to enhance the efficiency and accuracy of large-scale forest surveys in delineating three-dimensional forest structures and under-canopy *** study proposed an ALSbased framework to quantify tree growth and ***-temporal ALS data were used to quantify tree growth in height(ΔH),crown area(ΔA),crown volume(ΔV),and tree competition for 114,000 individual trees in two conifer-dominant Sierra Nevada *** analyzed the correlations between tree growth attributes and controlling factors(*** sizes,competition,forest structure,and topographic parameters)at multiple *** the individual tree level,ΔH had no consistent correlations with controlling factors,ΔA andΔV were positively related to original tree sizes(R>0.3)and negatively related to competition indices(R0.7),ΔV was positively related to original tree sizes(|R|>0.8).Multivariate regression models were simulated at individual tree level forΔH,ΔA,andΔV with the R2 ranged from 0.1 to *** ALS-based tree height estimation and growth analysis results were consistent with field measurements.

关键词： Airborne Laser Scanning change detection tree growth tree competition Sierra Nevada

Appendiceal bleeding caused by vascular malformation: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2457-2462页

作者： qin ma Jin-Jie Du Department of General Surgery Fuling Hospital Affiliated to Chongqing UniversityChongqing 408000China Department of Geriatrics Fuling Hospital Affiliated to Chongqing UniversityChongqing 408000China

BACKGROUND Acute lower gastrointestinal bleeding(LGIB)is a common occurrence in clinical ***,appendiceal bleeding is an extremely rare condition that can easily be overlooked and *** preoperative detection of appen-diceal bleeding often poses challenges due to the lack of related guidelines and consensus,resulting in controversial treatment *** SUMmaRY We presented a case of a 33-year-old female who complained of hematochezia that had lasted for 1 *** revealed continuous bleeding in the appen-diceal orifice.A laparoscopic appendectomy was performed immediately,and a pulsating blood vessel was observed in the mesangium of the appendix,accor-dingly,active bleeding into the appendicular lumen was *** examination revealed numerous hyperplastic vessels in the appendiceal mucosa and dilated capillary *** The preoperative detection of appendiceal bleeding is often challenging,colo-noscopy is extremely important,bowel preparation is not routinely recommend-ed for patients with acute LGIB or only low-dose bowel preparation is *** appendectomy is the most appropriate treatment for appendiceal bleeding.

关键词： Lower gastrointestinal bleeding Appendiceal bleeding Colonoscopy Vas-cular malformation Laparoscopic appendectomy Case report

Improved phenomenological nuclear charge radius formulae with kernel ridge regression

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Chinese Physics C 2022年第7期46卷 129-137页

作者： Jian-qin ma Zhen-Hua Zhang mathematies and Physics Department orth China Electric Power UniversityBeijing 102206China

The kernel ridge regression(KRR)method with Gaussian kernel is used to improve the description of the nuclear charge radius by several phenomenological *** widely used A^(1/3)A^(1/3),N^(1/3)N^(1/3)and Z^(1/3)Z^(1/3)formulae,and their improved versions by considering the isospin dependence are adopted as *** parameters in these six formulae are refitted using the Levenberg-marquardt method,which give better results than the previous *** radius for each nucleus is predicted with the KRR network,which is trained with the deviations between experimental and calculated nuclear charge *** each formula,the resultant root-mean-square deviations of 884 nuclei with proton number Z≥8 Z≥8 and neutron number N≥8 N≥8 can be reduced to about 0.017fm after considering the modification of the KRR *** extrapolation ability of the KRR method for the neutron-rich region is examined carefully and compared with the radial basis function *** is found that the improved nuclear charge radius formulae by KRR method can avoid the risk of overfitting and have a good extrapolation *** influence of the ridge penalty term on the extrapolation ability of the KRR method is also *** last,the nuclear charge radii of several recently observed K and Ca isotopes have been analyzed.

关键词： nuclear charge radius phenomenological formulae kernel ridge regression

GTB-PPI:Predict Protein-protein Interactions Based on L1-regularized Logistic Regression and Gradient Tree Boosting

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Genomics, Proteomics & Bioinformatics 2020年第5期18卷 582-592页

作者： Bin Yu Cheng Chen Hongyan Zhou Bingqiang Liu qin ma School of Life Sciences University of Science and Technology of ChinaHefei 230027China College of mathematics and Physics Qingdao University of Science and TechnologyQingdao 266061China Artificial Intelligence and Biomedical Big Data Research Center Qingdao University of Science and TechnologyQingdao 266061China School of mathematics Shandong UniversityJinan 250100China Department of Biomedical Informatics College of MedicineThe Ohio State UniversityColumbusOH 43210USA

Protein-protein interactions(PPIs)are of great importance to understand genetic mechanisms,delineate disease pathogenesis,and guide drug *** the increase of PPI data and development of machine learning technologies,prediction and identification of PPIs have become a research hotspot in *** this study,we propose a new prediction pipeline for PPIs based on gradient tree boosting(GTB).First,the initial feature vector is extracted by fusing pseudo amino acid composition(Pse AAC),pseudo position-specific scoring matrix(Pse PSSM),reduced sequence and index-vectors(RSIV),and autocorrelation descriptor(AD).Second,to remove redundancy and noise,we employ L1-regularized logistic regression(L1-RLR)to select an optimal feature ***,GTB-PPI model is ***-fold cross-validation showed that GTB-PPI achieved the accuracies of 95.15% and 90.47% on Saccharomyces cerevisiae and Helicobacter pylori datasets,*** addition,GTB-PPI could be applied to predict the independent test datasets for Caenorhabditis elegans,Escherichia coli,Homo sapiens,and Mus musculus,the one-core PPI network for CD9,and the crossover PPI network for the Wnt-related signaling *** results show that GTB-PPI can significantly improve accuracy of PPI *** code and datasets of GTB-PPI can be downloaded from https://***/QUST-AIBBDRC/GTB-PPI/.

关键词： Protein-protein interaction Feature fusion L1-regularized logistic regression Gradient tree boosting machine learning

Differential gene expression in nontransgenic and transgenic“M.26”apple overexpressing a peach CBF gene during the transition from eco-dormancy to bud break

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Horticulture Research 2019年第1期6卷 662-677页

作者： Timothy Artlip Adam McDermaid qin ma Michael Wisniewski USDA-ARS-Appalachian Fruit Research Station KearneysvilleWV 25430USA Agronomy Horticulture&Plant ScienceSouth Dakota State UniversityBrookingsSD 57007USA Imagenetics Sanford HealthSioux FallsSD 57007USA SBS-Biomedical Informatics The Ohio State UniversityColumbusOH 43210USA

The CBF signal pathway is responsible for a significant portion of plant responses to low temperature and *** of CBF genes in model organisms such as Arabidopsis thaliana enhances abiotic stress tolerance but also reduces *** addition to these effects,overexpression of the peach(Prunus persica[L.]Batsch)CBF1 gene in transgenic apple(malus x domestica Borkh.)line T166 also results in early entry into and late exit from *** the regulation of dormancy-induction and dormancy-release occur while the CBF regulon is operative in perennial,woody plants,how overexpression of CBF1 affects these dormancy-related changes in gene expression is incompletely *** objective of the present study was to characterize global changes in gene expression in peach CBF1-overexpressing and non-transformed apple bark tissues at different states of dormancy via *** bioinformatics data was confirmed by RT-qPCR on a number of *** indicate that the greatest number of significantly differentially expressed genes(DEGs)occurred in April when dormancy release and bud break normally occur but are delayed in Line *** involved in storage and inactivation of auxin,GA,and cytokinin were generally upregulated in T166 in April,while those for biosynthesis,uptake or signal transduction were generally downregulated in *** for cell division and cambial growth were also downregulated in T166 relative to the non-transformed *** data suggest that overexpression of the peach CBF1 gene impacts growth hormone homeostasis and as a result the activation of growth in the spring,and most likely growth cessation in the fall as well.

关键词： expressing break transformed