Search results for " Deriva"

showing 8 items of 718 documents

Iterative Methods for Pricing American Options under the Bates Model

2013

We consider the numerical pricing of American options under the Bates model which adds log-normally distributed jumps for the asset value to the Heston stochastic volatility model. A linear complementarity problem (LCP) is formulated where partial derivatives are discretized using finite differences and the integral resulting from the jumps is evaluated using simple quadrature. A rapidly converging fixed point iteration is described for the LCP, where each iterate requires the solution of an LCP. These are easily solved using a projected algebraic multigrid (PAMG) method. The numerical experiments demonstrate the efficiency of the proposed approach. Furthermore, they show that the PAMG meth…

ta113Mathematical optimizationStochastic volatilityDiscretizationIterative methodComputer scienceFinite difference methodLinear complementarity problemIterative methodQuadrature (mathematics)Multigrid methodFixed-point iterationBates modelLinear complementarity problemGeneral Earth and Planetary SciencesPartial derivativeAmerican optionGeneral Environmental ScienceProcedia Computer Science
researchProduct

The fractional tajimi-kanai model of earthquake gound motion

2013

tajimi kani modelgraound motionfractional derivative
researchProduct

Thiazole Analogues of the Marine Alkaloid Nortopsentin as Inhibitors of Bacterial Biofilm Formation

2020

Anti-virulence strategy is currently considered a promising approach to overcome the global threat of the antibiotic resistance. Among different bacterial virulence factors, the biofilm formation is recognized as one of the most relevant. Considering the high and growing percentage of multi-drug resistant infections that are biofilm-mediated, new therapeutic agents capable of counteracting the formation of biofilms are urgently required. In this scenario, a new series of 18 thiazole derivatives was efficiently synthesized and evaluated for its ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 25923 and S. aureus ATCC 6538 a…

thiazole derivativeAquatic OrganismsStaphylococcus aureusIndolesantibiotic resistanceSettore BIO/05 - ZoologiaPharmaceutical ScienceMicrobial Sensitivity TestsBacterial growthSettore BIO/19 - Microbiologia Generalemedicine.disease_cause01 natural sciencesArticlenortopsentinAnalytical ChemistryMicrobiologylcsh:QD241-441Inhibitory Concentration 50chemistry.chemical_compoundAlkaloidsAntibiotic resistancelcsh:Organic chemistryDrug DiscoverymedicinePhysical and Theoretical ChemistryThiazoleStrain (chemistry)010405 organic chemistryPseudomonas aeruginosamarine alkaloids analoguesAlkaloidOrganic ChemistryImidazolesBiofilmantibiofilm agentsSettore CHIM/08 - Chimica Farmaceuticamarine alkaloids analogueantibiofilm agent0104 chemical sciencesThiazoles010404 medicinal & biomolecular chemistrychemistryChemistry (miscellaneous)Staphylococcus aureusBiofilmsPseudomonas aeruginosathiazole derivativesMolecular MedicineMolecules
researchProduct

Crystal structure and Hirshfeld surface analysis of (Z)-4-chloro-N′-(4-oxothiazolidin-2-ylidene)benzenesulfonohydrazide monohydrate

2018

The asymmetric unit of the title thiazole derivative containing a sulfonylhydrazinic moiety, C9H8ClN3O3S2·H2O, consists of two independent molecules and two water molecules. The central parts of the molecules are twisted as both the molecules are bent at both the S and N atoms. In the crystal, N—H...N, N—H...O, C—H...O and O—H...O hydrogen-bonding interactions connect the molecules, forming layers parallel to the ab plane. Two-dimensional fingerprint plots associated with the Hirshfeld surface show that the largest contributions to the crystal packing come from O...H/H...O (32.9%) and H...H (22.6%) interactions.

thiazole derivativecrystal structureCrystallography010405 organic chemistryHydrogen bondBent molecular geometryGeneral ChemistryCrystal structure010403 inorganic & nuclear chemistryCondensed Matter PhysicsHydrazide01 natural sciences0104 chemical sciencesCrystalchemistry.chemical_compoundCrystallographychemistryQD901-999hydrogen bondsMoietyHirshfeld surface analysisGeneral Materials SciencePhysics::Chemical PhysicsBenzeneDerivative (chemistry)Acta Crystallographica Section E: Crystallographic Communications
researchProduct

Double copies of blaKPC-3::Tn4401a on an IncX3 plasmid in Klebsiella pneumoniae successful clone ST512 from Italy

2015

ABSTRACT A carbapenem-resistant sequence type 512 (ST512) Klebsiella pneumoniae carbapenemase 3 (KPC-3)-producing K. pneumoniae strain showing a novel variant plasmid content was isolated in Palermo, Italy, in 2014. ST512 is a worldwide successful clone associated with the spread of bla KPC genes located on the IncFIIk pKpQIL plasmid. In our ST512 strain, the bla KPC-3 gene was unusually located on an IncX3 plasmid, whose complete sequence was determined. Two copies of bla KPC-3 ::Tn 4401a caused by intramolecular transposition events were detected in the plasmid.

transposonsequence analysispolymerase chain reactionDrug ResistanceGene DosageSettore MED/42 - Igiene Generale E Applicatabacterial proteinbeta-Lactamaseopen reading framecarbapenemasePlasmidminocyclineplasmid DNAmeropenemPharmacology (medical)geneticscolistincefpodoximeceftazidime610 Medicine & healthCarbapenemBacterialpolymyxin Btimentingene expression regulationbacteriumKlebsiella pneumoniae carbapenemase 3 producing Klebsiella pneumoniae3. Good healthantiinfective agentmicrobial sensitivity testKlebsiella pneumoniaeItalypriority journaltigecyclineMultipleclone (Java method)cefotaxime030106 microbiologyKlebsiella pneumoniae carbapenemase 3tobramycinMicrobial Sensitivity Testsgentamicinpiperacillin plus tazobactamchemistryGene dosageArticleMicrobiology03 medical and health sciencesComplete sequenceClone CellOpen Reading FramesertapenemBacterial Proteinsmultidrug resistanceextensively drug resistant bacteriumAnti-Bacterial AgentcefepimePharmacologylevofloxacinmicrobiologycefoxitinbiochemical phenomena metabolism and nutritionbacterial infections and mycosesVirologyAnti-Bacterial Agents; Bacterial Proteins; Carbapenems; Clone Cells; Drug Resistance Multiple Bacterial; Gene Dosage; Italy; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Open Reading Frames; Plasmids; beta-Lactamases; DNA Transposable Elements; Gene Expression Regulation Bacterial; Pharmacology (medical); Pharmacology; Infectious Diseasesantibiotic sensitivityClone CellsKlebsiella InfectionsceftriaxoneCarbapenemsbacterial genetics0301 basic medicinemolecular cloningSettore MED/07 - Microbiologia E Microbiologia ClinicaKlebsiella pneumoniaeTransposition (music)Drug Resistance Multiple Bacterialpolycyclic compoundsgenetic screeningcell clonecarbapenem derivativeKlebsiella infectionunclassified drugAnti-Bacterial AgentsInfectious Diseasesbacterial genePlasmidsenzymologydoripenemBiologyminimum inhibitory concentrationbeta-Lactamasesbeta lactamaseMechanisms of ResistanceciprofloxacinAmikacin; aztreonam; carbapenemase; cefepime; cefotaxime; cefoxitin; cefpodoxime; ceftazidime; ceftriaxone; ciprofloxacin; colistin; cotrimoxazole; doripenem; doxycycline; ertapenem; gentamicin; imipenem; Klebsiella pneumoniae carbapenemase 3; levofloxacin; meropenem; minocycline; piperacillin plus tazobactam; plasmid DNA; polymyxin B; tigecycline; timentin; tobramycin; unclassified drug; antiinfective agent; bacterial protein; beta lactamase; carbapenem derivative; transposon antibiotic sensitivity; Article; bacterial gene; bacterial genetics; bacterial strain; bacterium; bacterium detection; bacterium isolation; Escherichia coli; extensively drug resistant bacterium; gene dosage; genetic screening; Italy; Klebsiella pneumoniae; Klebsiella pneumoniae carbapenemase 3 producing Klebsiella pneumoniae; minimum inhibitory concentration; molecular cloning; nonhuman; polymerase chain reaction; priority journal; sequence analysis; cell clone; chemistry; drug effects; enzymology; gene expression regulation; genetics; isolation and purification; Klebsiella infection; Klebsiella pneumoniae; metabolism; microbial sensitivity test; microbiology; multidrug resistance; open reading frame; plasmid; transposon Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamases; Carbapenems; Clone Cells; DNA Transposable Elements; Drug Resistance Multiple Bacterial; Gene Dosage; Gene Expression Regulation Bacterial; Italy; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests; Open Reading Frames; Plasmidsplasmidbacterium isolationEscherichia coliGeneAmikacinbacterium detectionnonhumandoxycyclineisolation and purificationGene Expression Regulation Bacterialbiology.organism_classificationbacterial straincotrimoxazoleOpen reading frameDNA Transposable Elementdrug effectsDNA Transposable Elementsmetabolismaztreonamimipenem
researchProduct

The Impact of a 1,2,3-Triazole Motif on the Photophysical Behavior of Non-K Tetrasubstituted Pyrene with a Substitution Pattern Providing the Long Ax…

2022

1,3,6,8-Tetrasubstituted pyrene derivatives with two types of substituents (4-(2,2-dimethylpropyloxy)pyridine, 1-decyl-1,2,3-triazole, 1-benzyl-1,2,3-triazole, and pyrazole), substituted in such a way that provides the long axial symmetry, are prepared and characterized in the present study. To the best of our knowledge, the pyrene derivative containing the same heteroaryl motif (triazole) but substituted by two various alkyls, straight decyl and benzyl-based side chains (C), is reported for the first time. For comparison, compounds with one kind of triazole motif and substituted pyridine or pyrazole groups were prepared (A and B). The photophysical properties of all molecules were evaluate…

triazole motifpyrene derivativestheoretical studysubstitution patternexperimental studyphotophysical propertiesMolecules
researchProduct

Remarks on regularity for p-Laplacian type equations in non-divergence form

2018

We study a singular or degenerate equation in non-divergence form modeled by the $p$-Laplacian, $$-|Du|^\gamma\left(\Delta u+(p-2)\Delta_\infty^N u\right)=f\ \ \ \ \text{in}\ \ \ \Omega.$$ We investigate local $C^{1,\alpha}$ regularity of viscosity solutions in the full range $\gamma>-1$ and $p>1$, and provide local $W^{2,2}$ estimates in the restricted cases where $p$ is close to 2 and $\gamma$ is close to 0.

viscosity solutionsintegrability of second derivativesType (model theory)01 natural sciencesDivergencelocal C1ViscosityMathematics - Analysis of PDEsFOS: Mathematicspartial differential equations0101 mathematicsMathematicsMathematical physicsosittaisdifferentiaaliyhtälötα regularityApplied Mathematics010102 general mathematicsta111p-Laplacianlocal C1α regularityviskositeettiDegenerate equation35J60 35B65 35J92010101 applied mathematicsviscosityp-LaplacianAnalysisAnalysis of PDEs (math.AP)Journal of Differential Equations
researchProduct

Ground and first excited electronic state interaction of FAD with some β-carboline derivatives

1987

Abstract The spectrophotometric and thermodynamic properties of molecular complexes of flavine adenine dinucleotide (FAD) with some dihydro β-carboline derivatives have been investigated in aqueous solution. The molecular associations have been examined by means of electronic absorption spectra, since in each a new charge-transfer band has been located, and also the variation of the fluorescence emission of FAD on the solutions has been observed. The formation constants for the molecular complexes were determined from absorption data, using the Foster-Hammick-Wardley method. The quenching fluorescence phenomena observed in FAD is related to the concentration of the dihydro β-carboline deriv…

β carboline derivativesAqueous solutionExcited electronic statebiologyAbsorption spectroscopyChemistryGeneral EngineeringPhotochemistryFluorescenceCofactorStability constants of complexesbiology.proteinPhysical chemistryheterocyclic compoundsAbsorption (chemistry)Spectrochimica Acta Part A: Molecular Spectroscopy
researchProduct