Search results for "BEM"
showing 10 items of 133 documents
BE analysis of delaminated Composite Structures repaired with Piezoelectric Active patches
2009
The main target of the present paper is the analysis of the fracture mechanics behavior of delaminated composite structures actively repaired through piezoelectric patches. The aim at issue has been achieved by using a boundary element code implemented to study piezoelectric solids, including, as limiting case, the applicability to linear elastic anisotropic materials. The assembled structures, made up of the damaged composite components and the piezoelectric patches, have been modelled through the multidomain technique. To take into account for the adhesive layer among the host structure and the active patch, an interface spring-model has been also implemented. The multidomain technique co…
Hierarchical adaptive cross approximation GMRES technique for solution of acoustic problems using the boundary element method
2009
In this paper a new Rapid Acoustic Boundary Element Method (RABEM) is presented using a Hierarchical GMRES solver for 3D acoustic problems. The Adaptive Cross Approximation is used to generate both the system matrix and the right hand side vector. The ACA is also used to evaluate the potential and the particle velocity values at selected internal points. Two different GMRES solution strategies (without preconditioner and with a block diagonal preconditioner) are developed and tested for low and high frequency problems. Implementation of different boundary conditions (i.e. Dirichlet, Neumann and mixed Robin) is also described. The applications presented include the problem of noise acting on…
Inhibition of dextromethorphan metabolism by moclobemide.
1998
This pilot study was conducted to evaluate the potential of the new antidepressant moclobemide to inhibit the cytochrome enzyme P4502D6 (CYP2D6) using the cough suppressant dextromethorphan as a substrate in four extensive metabolizers (EM) of debrisoquine. The subjects received seven oral doses of 20 mg dextromethorphan at 4-h intervals over 2 days (1 and 2) and subsequently moclobemide (300 mg b.i.d.) for 9 days. On days 10 and 11, they received seven doses of 20 mg dextromethorphan in addition to moclobemide. During monotreatment and combined treatment, blood was collected on days 2 and 11, respectively, for determination of dextromethorphan and its demethylated metabolites using automat…
The role of cytochrome P450 2D6 in the metabolism of moclobemide.
1996
The metabolic fate of moclobemide (Ro 11-1163), a new reversible and selective inhibitor of monoamine oxidase type A (MAO-A), has been assessed in a pilot study in 2 debrisoquine poor metabolizers (PM) and 4 extensive metabolizers (EM) after multiple oral dosings of moclobemide with and without co-medication of dextromethorphan. Absorption and disposition parameters were not different between PM and EM. Concurrent application of dextromethorphan, a selective substrate of CYP2D6, did not affect the pharmacokinetics of moclobemide. These results indicate that the cytochromal isoenzyme CYP2D6 does not play a major role in the metabolic degradation of moclobemide. Limited CYP2D6 activities beca…
CYP2D6 genotype and phenotyping by determination of dextromethorphan and metabolites in serum of healthy controls and of patients under psychotropic …
1998
Fourteen drug free healthy volunteers and 22 psychiatric patients under psychotropic medication were phenotyped for their individual CYP2D6 activity using dextromethorphan as a probe drug. A solution containing 20 mg dextromethorphan was administered and blood was taken 60 min later for determination of dextromethorphan and metabolites in serum. For comparison, urine was collected over 8 h after ingestion of 20 mg dextromethorphan in a separate test. The CYP2D6 phenotype was determined from the ratio of dextromethorphan to dextrorphan. For genotyping, mutant alleles of the CYP2D6 gene were identified using allele-specific polymerase chain reactions. Genotyping revealed five poor metabolizer…
Randomised placebo-controlled trial of moclobemide, cognitive–behavioural therapy and their combination in panic disorder with agoraphobia
1999
BackgroundIn the treatment of panic disorder with agoraphobia, the efficacy of pharmacological, psychological and combined treatments has been established. Unanswered questions concern the relative efficacy of such treatments.AimsTo demonstrate that moclobemide and cognitive–behavioural therapy (CBT) are effective singly and more effective in combination.MethodFifty-five patients were randomly assigned to an eight-week treatment of: moclobemide plus CBT; moclobemide plus clinical management (‘psychological placebo’); placebo plus CBT; or placebo plus clinical management.ResultsComparisons between treatments revealed strong effects for CBT. Moclobemide with clinical management was not superi…
Effects of moclobemide on sexual performance and nocturnal erections in psychogenic erectile dysfunction
2001
Rationale and objectives: We tested the hypothesis that the selective reversible MAO-A inhibitor moclobemide has a specific therapeutic effect on erectile dysfunction independent of its antidepressive properties. Methods: In a double-blind placebo controlled study, 12 male outpatients suffering from psychogenic erectile dysfunction without any other psychiatric disorder were investigated. Based on comprehensive diagnosis before the beginning of the study, organic factors relevant for sexual function were excluded. The treatment period was 8 weeks. Half the patients received 450 mg moclobemide during the first week, and 600 mg afterwards; the others received placebo. Apart from assessment of…
A comparison study of moclobemide and doxepin in major depression with special reference to effects on sexual dysfunction
1993
A double-blind parallel-group comparison study of moclobemide versus doxepin in 237 patients with major depression confirmed that moclobemide was equal in efficacy and better tolerated than doxepin. It was less sedating and caused fewer anticholinergic adverse events as measured by the UKU side-effect rating scale. Unexpectedly, moclobemide therapy more often than doxepin resulted in increased sexual desire. An exploratory analysis of UKU-measured symptoms of impaired sexual function prior to commencement of the study revealed that moclobemide more often than doxepin led to an improvement of reduced libido and impaired erection, ejaculation and orgasm. This finding is compatible with the as…
Hierarchical-ACA DBEM for Anisotropic Three-Dimensional Time-Harmonic Fracture Mechanics
2012
A hierarchical BEM solver for the analysis of three-dimensional anisotropic time-harmonic fracture mechanics problems is presented. A thorough investigation on the relations and interactions between the numerically computed anisotropic fundamental solutions and the algorithm used to approximate the blocks of the hierarchical matrix, namely Adaptive Cross Approximation, is carried out leading to the employed computational strategy. The use of the hierarchical matrices and iterative solvers is proved as an effective technique for speeding up the solution procedure and reducing the required memory storage in time-harmonic three-dimensional anisotropic fracture mechanics problems.
Poetiche della musica nell'antichità e nel rinascimento
2008
Tramite Aristosseno, Dionigi d'Alicarnasso e Pietro Bembo la poestica dell'antica musica ellenica del V secolo a.C. viene trasmessa ai compositori del madrigale polifonico italiano del Rinascimento.