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EXPONENTIAL INTEGRATORS FOR STOCHASTIC SCHRODINGER EQUATIONS DRIVEN BY ITO NOISE

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Journal of Computational Mathematics 2018年第2期36卷 276-309页

作者： Rikard Anton david Cohen Department of Mathematics and Mathematical Statistics Umea University SE-901 87 Umea Sweden Department of Mathematics University of Innsbruck A 6020 Innsbruck Austria

We study an explicit exponential scheme for the time discretisation of stochastic SchrS- dinger Equations Driven by additive or Multiplicative It6 Noise. The numerical scheme is shown to converge with strong order 1 if the noise is additive and with strong order 1/2 for multiplicative noise. In addition, if the noise is additive, we show that the exact solutions of the linear stochastic Sehr6dinger equations satisfy trace formulas for the expected mass, energy, and momentum （i. e., linear drifts in these quantities）. Furthermore, we inspect the behaviour of the numerical solutions with respect to these trace formulas. Several numerical simulations are presented and confirm our theoretical results.

关键词： Stochastic partial differential equations Stochastic SchrSdinger equations,Numerical methods Geometric numerical integration Stochastic exponential integrators,Strong convergence Trace formulas.

The Nobel Prize in Chemistry 2015:Exciting discoveries in DNA repair by Aziz Sancar

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Science China(Life Sciences) 2016年第1期59卷 97-102页

作者： david K.Orren Department of Toxicology and Cancer Biology University of Kentucky College of Medicine and Markey Cancer Center University of Kentucky

INTRODUCTIONOn October 7, 2015, the Nobel Prize in Chemistry for 2015 was awarded to three deserving scientists for their pioneer- ing research on DNA repair. Tomas Lindahl was recognized for studies that uncovered the inherent instability of DNA as well as the mechanism of the base excision repair pathway, Paul Modrich for characterization of the mismatch repair pathway, and Aziz Sancar for mechanistic elucidation of the nucleotide excision repair （NER） pathway. For me, the an- nouncement of these awards in my area of research was extremely gratifying, particularly so because Aziz was my mentor during my Ph.D. studies that examined the steps of prokaryotic NER. Memorably, I trained in the Sancar labor- atory at a time where groundbreaking discoveries were be- ing made in the burgeoning field of DNA repair, and can personally attest to his dedication and keen intellect.

关键词：诺贝尔化学奖 DNA修复兴奋桑

Deep resistivity "turnover" effect at oil generation "peak" in the Woodford Shale,Anadarko Basin,USA

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Petroleum Science 2019年第5期16卷 972-980页

作者： Ting Wang Jacobi david College of Resources and Environment Yangtze UniversityWuhan 430100China School of Geology and Geophysics University of OklahomaNormanOK 73019USA ConocoPhillips Company Houston 77079USA State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China Key Laboratory of Exploration Technology for Oil and Gas Research(Yangtze University) Ministry of EducationWuhan 430100China

The Devonian Woodford Shale in the Anadarko Basin is a highly organic,hydrocarbon source *** values of vitrinite reflectance(R_o)present in the Woodford Shale penetrated by 52 control wells were measured *** vitrinite reflectance values,when plotted against borehole resistivity for the middle member of the Woodford Shale in the wells,display a rarely reported finding that deep resistivity readings decrease as R_o increases when R_o is greater than 0.90%.This phenomenon may be attributed to that aromatic and resin compounds containing conjugated pi bonds generated within source rocks are more electrically conductive than aliphatic *** aromatic and resin fractions were generated more than aliphatic fraction when source rock maturity further increases beyond oil *** finding of the relationship between deep resistivity and R_o may re-investigate the previously found linear relationship between source rock formation and aid to unconventional play exploration.

关键词： Resistivity log Source rock thermal maturity Vitrinite reflectance Woodford Shale

Hermitian Generalization of the Rarita-Schwinger Operators

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Acta Mathematica Sinica,English Series 2010年第2期26卷 311-330页

作者： Alberto DAMIANO david EELBODE Mathematics Institute of Charles University Department of Mathematics and Computer Science University of Antwerp

We introduce two new linear differential operators which are invariant with respect to the unitary group SU（n）. They constitute analogues of the twistor and the Rarita-Schwinger operator in the orthogonal case. The natural setting for doing this is Hermitian Clifford Analysis. Such operators are constructed by twisting the two versions of the Hermitian Dirac operator 6z_ and 6z_ and then projecting on irreducible modules for the unitary group. We then study some properties of their spaces of nullsolutions and we find a formulation of the Hermitian Rarita-Schwinger operators in terms of Hermitian monogenic polynomials.

关键词： Hermitian Clifford analysis Rarita-Schwinger operator

Total Graphs Are Laplacian Integral

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Algebra Colloquium 2022年第3期29卷 427-436页

作者： david Dolžan Polona Oblak Department of Mathematics Faculty of Mathematics and Physics University of LjubljanaJadranska 21SI-1000 LjubljanaSlovenia Facultyof Computerand Information Science University of Ljubljana Vecna pot 113SI-1000 LjubljanaSlovenia

We prove that the Laplacian matrix of the total graph of a finite commutative ring with identity has integer eigenvalues and present a recursive formula for computing its eigenvalues and *** also prove that the total graph of a finite commutative local ring with identity is super integral and give an example showing that this is not true for arbitrary rings.

关键词： eigenvalue eigenvector Laplacian matrix total graph Laplacian integral

Weedy red rice has novel sources of resistance to biotic stress

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The Crop Journal 2018年第5期6卷 443-450页

作者： Yulin Jia david Gealy USDA Agricultural Research Service Dale Bumpers National Rice Research Center

Weedy red rice(Oryza sativa;WRR),a close relative of cultivated rice,is a highly competitive weed that commonly infests rice fields and can also naturally interbreed with *** genes for biotic stress have been maintained in WRR and can be explored for *** we describe genetic and physiological traits of WRR that can be beneficial in preventing major rice *** blast,caused by the hemibiotrophic fungal pathogen Magnaporthe oryzae,and sheath blight disease,caused by the necrotrophic pathogen Rhizoctonia solani,are the two most damaging biotic stresses of *** major and minor resistance genes and QTL have been identified in cultivated and wild rice ***,novel QTL were recently found in the two major *** of WRR,blackhull-awned(BH)and strawhullawnless(SH),suggesting that WRR has evolved novel genetic mechanisms to cope with these biotic ***-eight accessions of WRR(PI 653412–PI 653439)from the southern USA were characterized and placed in the National Small Grains Collection,and are available for identification of novel genetic factors to prevent biotic stress.

关键词： Weedy red rice Oryza sativa Geng Aus Blast disease Sheath blight disease

TagCombine： Recommending Tags to Contents in Software Information Sites

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Journal of Computer Science & Technology 2015年第5期30卷 1017-1035页

作者：王新宇夏鑫 david Lo 1.College of Computer Science and Technology Zhejiang University Hangzhou 310027 China 2.School of Information Systems Singapore Management University Singapore Singapore

Nowadays, software engineers use a variety of online media to search and become informed of new and interesting technologies, and to learn from and help one another. We refer to these kinds of online media which help software engineers improve their performance in software development, maintenance, and test processes as software information sites. In this paper, we propose TagCombine, an automatic tag recommendation method which analyzes objects in software information sites. TagCombine has three different components： 1） multi-label ranking component which considers tag recommendation as a multi-label learning problem; 2） similarity-based ranking component which recommends tags from similar objects; 3） tag-term based ranking component which considers the relationship between different terms and tags, and recommends tags after analyzing the terms in the objects. We evaluate TagCombine on four software information sites, Ask Different, Ask Ubuntu, Feecode, and Stack Overflow. On averaging across the four projects, TagCombine achieves recall@5 and recallS10 to 0.619 8 and 0.762 5 respectively, which improves TagRec proposed by Al-Kofahi et al. by 14.56% and 10.55% respectively, and the tag recommendation method proposed by Zangerle et al. by 12.08% and 8.16% respectively.

关键词： software information site online media tag recommendation

Duplication and diversification of insulin genes in ray-finned fish

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Zoological Research 2019年第3期40卷 185-197页

作者： david M.Irwin Department of Laboratory Medicine and Pathobiology University of Toronto Banting and Best Diabetes Centre University of Toronto

Insulin is a key hormone for the regulation of metabolism in *** is produced by pancreatic islet cells in response to elevated glucose levels and leads to the uptake of glucose by tissues such as liver and adipose tissue to store *** also has additional functions in regulating *** work has shown that the proglucagon gene,which encodes hormones counter regulating insulin,is duplicated in teleost fish,and that the peptide hormones encoded by these genes have diversified in function.I sought to determine whether similar processes have occurred to insulin genes in these *** of fish genomes revealed an unexpected diversity of insulin genes.A triplication of the insulin gene occurred at the origin of teleost fish,however one of these three genes,insc,has been lost in most teleost fish *** two other insulin genes,insa and insb,have been retained but show differing levels of selective constraint suggesting that they might have diversified in ***,a duplicate copy of the insa gene,which I named insab,is found in many *** coding sequenee encoded by insab genes is under weak selective constraint,with its predicted protein sequences losing their potential to be processed into a two-peptide ***,these sequences have retained perfectly conserved cystine residues,suggesting that they maintain insulin's three-dimensional structure and therefore might modulate the processing and secretion of insulin produced by the other genes.

关键词： Insulin Teleost fish Gene duplicati on Adaptive evolution Gene loss

Gastroesophageal reflux following peroral endoscopic myotomy for achalasia:Bumps in the road to success

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World Journal of Gastroenterology 2024年第29期30卷 3461-3464页

作者： david Itskoviz Stephen david Howard Malnick Kaplan Medical Center Institute of Gastroenterology and HepatologyHebrew University Medical School of JerusalemRehovot 76100Israel Kaplan Medical Center Department of Internal Medicine CHebrew University Medical School of JerusalemRehovot 76100Israel

Achalasia can significantly impair the quality of *** clinical presentation typically includes dysphagia to both solids and liquids,chest pain,and *** can be delayed in patients with atypical presentations,and they might receive a wrong diagnosis,such as gastroesophageal reflux disease(GERD),owing to overlapping symptoms of both *** the cause of achalasia is poorly understood,its impact on the motility of the esophagus and gastroesophageal junction is well *** treatment modalities have been utilized,with the most common being surgical Heller myotomy with concomitant fundoplication and pneumatic balloon ***,peroral endoscopic myotomy(POEM)has gained popularity as an effective treatment for achalasia,despite a relatively high incidence of GERD occurring after treatment compared to other *** magnitude of post-POEM GERD depends on its definition and is influenced by patient and procedure-related *** longterm sequelae of post-POEM GERD are yet to be determined,but it appears to have a benign course and is usually manageable with clinically available *** risk factors for post-POEM GERD and modifying the POEM procedure in selected patients may improve the overall success of this technique.

关键词： Achalasia Per-oral endoscopic myotomy Gastroesophageal reflux Pneumatic dilatation Heller myotomy Proton pump inhibitor Acidic fermentation