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At least 1,333 records · Page 74Linked to original sources
PubMed1997

Antiproliferative effect of c-myc antisense phosphorothioate oligodeoxynucleotides in malignant glioma cells.

OBJECTIVE: To improve the prognosis for primary malignant tumors of the central nervous system, new therapeutic strategies are needed. Antisense oligodeoxynucleotides (ODNs) offer the potential to block the expression of specific genes within cells. The proto-oncogene c-myc has long been implicated in the control of normal cell growth and its deregulation in the development of neoplasia. We therefore reasoned that a strategy using ODNs complementary to c-myc messenger ribonucleic acid would be a potent inhibitor of glioma cell proliferation. METHODS: A variety of antisense, sense, and scrambled (15-mer) phosphorothioate ODNs targeted to rat and human c-myc messenger ribonucleic acid were synthesized and added to the media of cultured RT-2 cells (a rat glioblastoma cell line). Cell growth was assessed by 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide dye assay 1 to 5 days after adding the ODNs. c-Myc protein expression was analyzed by Western blot analysis. The stability of the ODNs was confirmed by gel electrophoresis. RESULTS: Compared with cultures containing standard media, two of three antisense ODNs significantly inhibited the growth of glioma cells, whereas sense and scrambled sequence ODNs did not significantly affect cell growth at the concentrations tested. A human c-myc antisense sequence, which differed from the rat sequence by one base substitution, also had an inhibitory effect on RT-2 cells. Western blot analysis demonstrated that expression of immunoreactive c-Myc protein was also greatly reduced in the rat antisense ODN-treated cells (and not in sense-, scrambled-, or control-treated cells). The degree of reduction of c-Myc protein expression correlated well with the decrease in cell growth observed with several antisense ODNs. Phosphorothioate ODNs were stable in cell culture media for at least 5 days. CONCLUSION: These results suggest that c-Myc plays a critical role in glioma cell proliferation and demonstrate that antisense ODNs can suppress proto-oncogene expression and inhibit the proliferation of glioma cells. Our results indicate that the antiproliferative activity of these ODNs was mediated predominantly through sequence-specific antisense mechanisms, but that sequence-specific nonantisense effects may also contribute to the strongest effects demonstrated. These findings support a potential role for antisense strategies designed to inhibit c-myc expression in the treatment of malignant gliomas.

Animals↗
PubMed2002

Large-scale structure-function analysis of the Arabidopsis RPM1 disease resistance protein.

The Arabidopsis RPM1 gene confers resistance against Pseudomonas syringae expressing either the AvrRpm1 or the AvrB type III effector protein. We present an exhaustive genetic screen for mutants that no longer recognize avrRpm1. Using an inducible avrRpm1 expression system, we identified 110 independent mutations. These mutations represent six complementation groups. None discriminates between avrRpm1 and avrB recognition. We identified 95 rpm1 alleles and present a detailed structure--function analysis of the RPM1 protein. Several rpm1 mutants retain partial function, and we deduce that their residual activity is dependent on the level of avrRpm1 signal. In these mutants, the hypersensitive response remains activated if the signal goes above a certain threshold. Missense mutations in rpm1 are highly enriched in the nucleotide binding domain, suggesting that this region plays a key role either in the hypersensitive response associated with RPM1 activation or in RPM1 stability. Cluster analysis of rpm1 alleles defines functionally important residues that are highly conserved between nucleotide binding site leucine-rich repeat R proteins and those that are unique to RPM1. Regions of RPM1 to which no loss-of-function alleles map may represent domains in which variation is tolerated and may contribute to the evolution of new R gene specificities.

Alleles↗
PubMed2004

Chromatographic analysis and sequencing approach of heparin oligosaccharides using cetyltrimethylammonium dynamically coated stationary phases.

C(18) and C(8) bonded stationary phases dynamically coated with cetyltrimethylammonium (CTA) and strong anion exchange (SAX) were developed to obtain separations of oligosaccharide mixtures resulting from chemical or enzymatic depolymerization of heparin. With this method, the retention of sulfated oligosaccharides is directly adjustable depending on the amount of CTA adsorbed into the column. Oligosaccharides containing up to 20 sulfates were separated with a resolving power superior to that of conventional SAX analysis. The stability of the column coating enables hundreds of injections. Using ammonium methane sulfonate aqueous solutions as ultraviolet transparent mobile phases, it was possible to set up double detection, including selective detection of acetylated oligosaccharides. Analytical gel permeation chromatography was directly coupled to CTA-SAX, obtaining a two-dimensional profile of analyzed oligosaccharidic mixtures. A sequencing method of heparin oligosaccharides using partial depolymerization by heparinases according to their size and sulfation pattern and digest analysis by CTA-SAX was developed. A direct application of this method to the analysis of oligosaccharide mixtures obtained by complete digestion of heparins by heparinases I, II, and III was done. It allowed a reliable quantification of heparin building blocks. We also focused our attention on di- and tetrasaccharidic species containing the 3-O-sulfated glucosamines taken as markers of the active sites for antithrombin III. The method was also applied to more complex mixtures resulting from porcine heparin partially depolymerized with heparinase I. The specificity of the reaction was studied up to decasaccharidic fractions.

Animals↗
PubMed1993

Site-directed mutagenesis of the genome of mouse hepatitis virus by targeted RNA recombination.

We have genetically characterized a nucleocapsid (N) protein mutant of the coronavirus mouse hepatitis virus (MHV). This mutant, designated Alb4, is both temperature-sensitive and thermolabile, and its N protein is smaller than wild-type N. Sequence analysis of the Alb4 N gene revealed that it contains an internal deletion of 87 nucleotides, producing an in-frame deletion of 29 amino acids. All of these properties of Alb4 made it ideal for use as a recipient in a targeted RNA recombination experiment in which the deletion in Alb4 was repaired by recombination with synthetic RNA7, the smallest MHV subgenomic mRNA. Progeny from a cotransfection of Alb4 genomic RNA and synthetic RNA7 were selected for thermal stability. PCR analysis of candidate recombinants showed that they had regained the material that is deleted in the Alb4 mutant. They also had acquired a five nucleotide insertion in the 3' untranslated region, which had been incorporated into the synthetic RNA7 as a molecular tag. The presence of the tag was directly verified, as well, by sequencing the genomic RNA of purified recombinant viruses. This provided a clear genetic proof that the Alb4 phenotype was due to the observed deletion in the N gene. In addition, these results demonstrated that it is possible to obtain stable, independently replicating progeny from recombination between coronaviral genomic RNA and a tailored, synthetic RNA species. To date, we have constructed three additional mutants by this procedure. For two of these, a second-site point mutation that reverts the Alb4 phenotype has been transduced into a wild type background, which does not contain the Alb4 deletion.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1989

Analysis of single-stranded DNA stability and damage-induced strand loss in mammalian cells using SV40-based shuttle vectors.

The fate and stability of fully or partially single-stranded DNA molecules transfected into mammalian cells have been analysed. For this, we constructed a simian virus 40 (SV40)-based shuttle vector containing the f1 bacteriophage replication origin in the two possible orientations (pi SVF1-A and pi SVF1-B). This vector contains the SV40 origin of replication, the late viral genes and DNA sequences for replication and selection in Escherichia coli. It also carries the lacO sequence, which permits the analysis of plasmid stability. Single-stranded DNA from pi SVF1-A and pi SVF1-B were produced in bacteria and annealed in vitro to form a heteroduplex molecule. We showed that, in monkey kidney COS7 cells, single-stranded vectors replicate to form duplex molecules. After transfection of the three forms of molecules (single-stranded, heteroduplex or double-stranded), replicated DNA was rescued in E. coli. Vector stability was analysed by checking for plasmid rearrangements and screening for lacO mutants. The single-stranded pi SVF1 has a lower rearrangement level, while the spontaneous mutation frequency (on the lacO target) is in the same range as for the double-stranded vector. In contrast, the level of spontaneous mutagenesis is higher for the heteroduplex than for the single- and double-stranded forms. In addition, we found that replication of heteroduplex with one strand containing ultraviolet light-induced lesions yields progeny molecules in which the irradiated strand is mostly lost. This result indicates for the first time the specific loss of the damaged strand in mammalian cells.

Animals↗
PubMed1991

Analysis of the conformation and stability of Escherichia coli derived recombinant human interleukin 4 by circular dichroism.

The conformation and stability of Escherichia coli derived recombinant human interleukin 4 (rhuIL-4) have been examined by circular dichroism (CD). Protein unfolding was detected by ellipticity changes at 222 nm with increasing concentrations of guanidine hydrochloride (GdnHCl). The unfolding midpoint ([GdnHCl]1/2) was 3.7 M, the free energy of unfolding, (delta GDH2O), was 5.9 kcal/mol and the dependence of delta GD on the GdnHCl concentration (m) was 1.6 (kcal/mol)/M. This unfolding was demonstrated to be reversible upon removal of the GdnHCl by dialysis. Analysis of the far-UV CD spectrum indicated the presence of a high percentage of alpha-helical structure (ca. 73%). A small change in ellipticity was noted over the pH range 1.9-9.6, suggesting that the protein undergoes a minor conformational change with an apparent pKa of 4.17. Virtually complete biological activity, measured in vitro in a T-cell proliferation assay, was recovered following exposure to extreme values of pH (i.e., pH 3 and 10). An analysis of the near-UV CD spectrum indicated that the single tryptophan residue at position 91 was unconstrained and most likely exposed to the solvent. Titration with 4,4'-dithiodipyridine and 2-nitrothiosulfobenzoate established that the six cysteine residues in rhuIL-4 were involved in intramolecular disulfide linkages. These data support that rhuIL-4 has a highly stable three-dimensional structure.

Circular Dichroism↗
PubMed2004

A biosensor for the analysis of acetonitrile.

A biosensor for monitoring acetonitrile was constructed. A mixed culture was taken from a degradation reactor and mounted on top of a Clark electrode. The amperometric biosensor was placed in a flow-through cell and integrated into a flow injection system. The metabolic response in terms of oxygen consumption was well correlated to the concentration of acetonitrile in standard solutions. However, when the reaction products, acetic acid and ammonia, were also present, the response was erratic, due to the additional metabolic reaction on acetate. By introducing a hydrophobic barrier it was possible to eliminate the negative influence of these charged products and thus to improve the operational selectivity of the sensor. The biosensor showed good stability for analysis during at least 6 days and future work will focus on using it for monitoring and control of degradation processes.

Acetonitriles↗
PubMed2004

Engineering of a polymeric bacterial protein as a scaffold for the multiple display of peptides.

Protein assemblies with a high degree of repetitiveness and organization are known to induce strong immune responses. For that reason they have been postulated for the design of subunit vaccines by means of protein engineering. The enzyme lumazine synthase from Brucella spp. (BLS) is highly immunogenic, presumably owing to its homodecameric arrangement and remarkable thermodynamic stability. Structural analysis has shown that it is possible to insert foreign peptides at the ten amino terminus of BLS without disrupting its general folding. These peptides would be displayed to the immune system in a highly symmetric three-dimensional array. In the present work, BLS has been used as a protein carrier of foreign peptides. We have established a modular system to produce chimeric proteins decorated with ten copies of a desired peptide as long as 27 residues and have shown that their folding and stability is similar to that of the wild-type protein. The knowledge about the mechanisms of dissociation and unfolding of BLS allowed the engineering of polyvalent chimeras displaying different predefined peptides on the same molecular scaffold. Moreover, the reassembly of mixtures of chimeras at different steps of the unfolding process was used to control the stoichiometry and spatial arrangement for the simultaneous display of different peptides on BLS. This strategy would be useful for vaccine development and other biomedical applications.

Amino Acid Sequence↗
PubMed2002

[Radiolunate arthrodesis of the rheumatoid wrist - mid- and long-term results].

Late Synovectomy of the rheumatoid wrist combined with ulna head resection and dorsal wrist stabilization will not prevent carpal instability and dislocation. Depending on the radiological destruction pattern and the natural course of the wrist according to Simmen, dorsal wrist synovectomy is combined with soft-tissue or osseus stabilization procedures.This article describes the mid- and long-term results of radio-lunate arthrodesis in patients with rheumatoid arthritis. We present a retrospective study of 69 radiolunate arthrodesis performed from 1988 to 1994. Fifty patients with 57 wrists were available for clinical and radiological follow-up. All patients were suffering from rheumatoid arthritis (dominating female). The average length of R.A. illness was 9.6 years. The mean age at operation was 54.4 years. Postoperative results were reviewed with the Clayton score. The radiographic analysis included measurement of the carpal height index and ulnar translation of the carpus. The follow-up period ranged from 4 to 10.8 years (average: 7 years). The postoperative Clayton score averaged 74.2 points, representing 70% good or excellent results. Twelve wrists achieved satisfactory results and five were judged poor. The most benefit was achieved in pain relief and restoration of wrist function and extensor strength. Complete pain relief was achieved in 36 wrists, while 16 reported slight pain from loads. Five patients still complained about pain with daily wrist activity. We noticed a moderate decrease for extension-flexion (-39 degrees ) and for combined ulnar-radial deviation (-10 degrees ). The radiographic analysis proved stabilization of ulnar translocation in most cases. We routinely noticed a moderate radiographic progression according to the Larsen classification (+0.7) with reduction of the carpal height ratio. In conclusion radioulnate arthrodesis proved satisfactory pain relief and maintenance of functional wrist motion. Despite radiographic deterioration, partial wrist arthrodesis restrains ulnar translocation, while stabilization of the rheumatoid wrist is achieved.

Adult↗
PubMed1997

Phase response characteristics of model neurons determine which patterns are expressed in a ring circuit model of gait generation.

In order to assess the relative contributions to pattern-generation of the intrinsic properties of individual neurons and of their connectivity, we examined a ring circuit composed of four complex physiologically based oscillators. This circuit produced patterns that correspond to several quadrupedal gaits, including the walk, the bound, and the gallop. An analysis using the phase response curve (PRC) of an uncoupled oscillator accurately predicted all modes exhibited by this circuit and their phasic relationships--with the caveat that in certain parameter ranges, bistability in the individual oscillators added nongait patterns that were not amenable to PRC analysis, but further enriched the pattern-generating repertoire of the circuit. The key insights in the PRC analysis were that in a gait pattern, since all oscillators are entrained at the same frequency, the phase advance or delay caused by the action of each oscillator on its postsynaptic oscillator must be the same, and the sum of the normalized phase differences around the ring must equal to an integer. As suggested by several previous studies, our analysis showed that the capacity to exhibit a large number of patterns is inherent in the ring circuit configuration. In addition, our analysis revealed that the shape of the PRC for the individual oscillators determines which of the theoretically possible modes can be generated using these oscillators as circuit elements. PRCs that have a complex shape enable a circuit to produce a wider variety of patterns, and since complex neurons tend to have complex PRCs, enriching the repertoire of patterns exhibited by a circuit may be the function of some intrinsic neuronal complexity. Our analysis showed that gait transitions, or more generally, pattern transitions, in a ring circuit do not require rewiring the circuit or any changes in the strength of the connections. Instead, transitions can be achieved by using a control parameter, such as stimulus intensity, to sculpt the PRC so that it has the appropriate shape for the desired pattern(s). A transition can then be achieved simply by changing the value of the control parameter so that the first pattern either ceases to exist or loses stability, while a second pattern either comes into existence or gains stability. Our analysis illustrates the predictive value of PRCs in circuit analysis and can be extended to provide a design method for pattern-generating circuits.

Animals↗
PubMed2004

Simultaneous HPLC determination of ketoprofen and its degradation products in the presence of preservatives in pharmaceuticals.

A novel and quick high-performance liquid chromatography (HPLC) method with UV spectrophotometric detection was developed and validated for the determination of five compounds in topical gel. The described method is suitable for simultaneous determination of active component ketoprofen, two preservatives methylparaben and propylparaben and two degradation products of ketoprofen--3-acetylbenzophenone and 2-(3-carboxyphenyl) propionic acid--in a topical cream after long-term stability tests using ethylparaben as an internal standard. The chromatographic separation was performed on a 5microm Supelco Discovery C18 column (125mm x 4mm i.d., Sigma-Aldrich); the optimal mobile phase for separation of ketoprofen, methylparaben, propylparaben, degradation products 3-acetylbenzophenone and 2-(3-carboxyphenyl) propionic acid and ethylparaben as internal standard consists of a mixture of acetonitril, water and phosphate buffer pH 3.5 (40:58:2, v/v/v). At a flow rate of 1.0ml min(-1) and detection at 233nm, the total time of analysis was less than 10min. The method was applied for routine analysis (batch analysis and stability tests) of these compounds in topical pharmaceutical product.

Chromatography, High Pressure Liquid↗
PubMed1987

A reference data base for multilead electrocardiographic computer measurement programs.

In an effort to standardize and evaluate the performance of electrocardiographic computer measurement programs, a 15 lead reference library has been developed based on simultaneously recorded standard 12 lead and orthogonal XYZ lead data. A set of 250 electrocardiograms (ECGs) with selected abnormalities was analyzed by a group of five referee cardiologists and 11 different 12 lead and 6 XYZ computer programs. Attention was focused on the exact determination of the onsets and offsets of P, QRS and T waves. The referees performed their task on highly amplified, selected complexes from the library in a two round process. Median results of the referees coincided best with the median derived from all programs. An analysis of stability proved that the combined program median was a robust reference. However, some individual program results were widely divergent. Paired t tests demonstrated earlier onset for P and QRS (p less than 0.001), as well as later offset for P and T waves in the median 12 lead than in the XYZ results. Significant differences also existed among results obtained by programs analyzing all standard ECG leads at one time, the so-called multilead programs, and those obtained by the conventional standard three lead analysis programs. As a consequence, the derived P, PR, QRS and QT interval measurements varied quite widely among the various programs. Significant differences were also observed among measurements of Q, R and S duration. Some programs showed Q waves that were on the average 6 ms (p less than 0.001) longer than those of others. This may significantly influence diagnostic performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrocardiography↗
PubMed1997

Plasmid maintenance functions of the large virulence plasmid of Shigella flexneri.

The large virulence plasmid pMYSH6000 of Shigella flexneri contains a replicon and a plasmid maintenance stability determinant (Stb) on adjacent SalI fragments. The presence of a RepFIIA replicon on the SalI C fragment was confirmed, and the complete sequence of the adjacent SalI O fragment was determined. It shows homology to part of the transfer (tra) operon of the F plasmid. Stb stabilizes a partition-defective P1 miniplasmid in Escherichia coli. A 1.1-kb region containing a homolog of the F trbH gene was sufficient to confer stability. However, the trbH open reading frame could be interrupted without impairing stability. Deletion analysis implicated the involvement of two small open reading frames, STBORF1 and STBORF2, that fully overlap trbH in the opposite direction. These open reading frames are closely related to the vagC and vagD genes of the Salmonella dublin virulence plasmid and to open reading frame pairs in the F trbH region and in the chromosomes of Dichelobacter nodosus and Haemophilus influenzae. Stb appears to promote better-than-random distribution of plasmid copies and is a plasmid incompatibility determinant. The F homolog does not itself confer stability but exerts incompatibility against the activity of the Stb system. Stb is likely to encode either an active partition system or a postsegregational killing system. It shows little similarity to previously studied plasmid stability loci, but the genetic organization of STBORF1 and STBORF2 resembles that of postsegregational killing mechanisms.

Amino Acid Sequence↗
PubMed2006

Distance-based tests for homogeneity of multivariate dispersions.

The traditional likelihood-based test for differences in multivariate dispersions is known to be sensitive to nonnormality. It is also impossible to use when the number of variables exceeds the number of observations. Many biological and ecological data sets have many variables, are highly skewed, and are zero-inflated. The traditional test and even some more robust alternatives are also unreasonable in many contexts where measures of dispersion based on a non-Euclidean dissimilarity would be more appropriate. Distance-based tests of homogeneity of multivariate dispersions, which can be based on any dissimilarity measure of choice, are proposed here. They rely on the rotational invariance of either the multivariate centroid or the spatial median to obtain measures of spread using principal coordinate axes. The tests are straightforward multivariate extensions of Levene's test, with P-values obtained either using the traditional F-distribution or using permutation of either least-squares or LAD residuals. Examples illustrate the utility of the approach, including the analysis of stabilizing selection in sparrows, biodiversity of New Zealand fish assemblages, and the response of Indonesian reef corals to an El Niño. Monte Carlo simulations from the real data sets show that the distance-based tests are robust and powerful for relevant alternative hypotheses of real differences in spread.

Animals↗
PubMed2000

Paper-based archiving of mammalian and plant samples for RNA analysis.

The ability to archive biological samples for subsequent nucleic acid analysis is essential for tissue specimens and forensic samples. FTA Card is a chemically treated filter paper designed for the collection and room temperature storage of biological samples for subsequent DNA analysis. Its usefulness for the preservation of biological samples for subsequent RNA analysis was tested. Here, we demonstrate that RNA in biological samples stored on FTA Cards is stable and can be used successfully for RT-PCR and northern blot analysis. RNA stability depends on the storage temperature and the type of biological specimen. RNA in mammalian cells stored on FTA Cards is stable for over one year at temperatures at or below -20 degrees C and for two to three months in samples stored at room temperature. For plant leaf, longer storage times (> 5 days) require temperatures at or below -70 degrees C following sample application. FTA Cards may constitute a method not only for convenient collection and storage of biological samples but also for rapid RT-PCR analysis of tissue and cell samples.

Animals↗
PubMed1992

Ternary complex formation by vaccinia virus RNA polymerase at an early viral promoter: analysis by native gel electrophoresis.

We have resolved, by native gel electrophoresis, two intermediates in the transcription of a vaccinia virus early gene by the virus-encoded RNA polymerase. Polymerase holoenzyme containing the vaccinia virus early transcription factor (VETF) forms a complex of VETF bound to the promoter as the first step in a pathway leading to establishment of a committed ternary elongation complex. Formation of the VETF-DNA complex is stimulated by magnesium but is uninfluenced by nucleoside triphosphates. A stable binary complex of RNA polymerase bound to DNA is not detected. Assembly of a gel-stable polymerase-DNA complex depends on conditions permissive for RNA synthesis. Nucleotide omission experiments suggest that at least a tetrameric RNA must be made before a ternary complex is stabilized. RNA analysis indicates that complexes containing nascent transcripts 20 nucleotides long are stable and active. Ternary complex formation requires hydrolyzable ATP. This is consistent with an essential role for the ATPase activity of VETF at a step subsequent to DNA binding, as proposed by Broyles (S. S. Broyles, J. Biol. Chem. 266:15545-15548, 1991). The ternary complex, once formed, is resistant to dissociation by competitor DNA, as well as by salt, Sarkosyl, and heparin. The effects of these inhibitory agents on transcription complex formation suggest that they target different steps in the assembly pathway.

Base Sequence↗
PubMed2005

In situ stabilization of toxic metals in polluted soils using phosphates: theoretical prediction and experimental verification.

The in situ (in place) immobilization of toxic metals, using inexpensive "reactive" amendments, is considered as a simple and cost-effective approach for the treatment of soils, contaminated by the presence of heavy metals, when these soils are difficult or costly to be removed and treated ex situ. Several application studies have demonstrated that the stabilization of contaminated soils and groundwaters by the addition of apatite minerals has the potential to be a successful and widely applicable remediation strategy for the case of Pb, Cd, as well as for other toxic metals, existing in polluted soils. On the other hand, the specific immobilization mechanism(s) of these toxic metals remains rather elusive. The present work involves an interdisciplinary theoretical and experimental approach, designed to gain at the fundamental (molecular) level the understanding of respective mechanisms, considering the immobilization of Pb and Cd by the addition of apatites. The theoretical analysis of stability, regarding the apatite/Pb or apatite/Cd systems and the relevant results of sorption experiments, pointed out two different mechanisms for the immobilization of Pb or Cd by the use of apatites. The possible practical consequences of these findings for the selection/application of natural apatites for the remediation of contaminated soils by the presence of heavy metals have been also discussed.

Cadmium↗
PubMed1998

Analysis of 3D transient blood flow passing through an artificial aortic valve by Lattice-Boltzmann methods.

The development of flow instabilities due to high Reynolds number flow in artificial heart valve geometries inducing high strain rates and stresses often leads to hemolysis and related highly undesired effects. Geometric and functional optimization of artificial heart valves is therefore mandatory. In addition to experimental work in this field it is meanwhile possible to obtain increasing insight into flow dynamics by computer simulation of refined model problems. After giving an introductory overview we report the results of the simulation of three-dimensional transient physiological flows in fixed geometries similar to a CarboMedics bileaflet heart valve at different opening angles. The visualization of emerging complicated flow patterns gives detailed information about the transient history of the systems dynamical stability. Stress analysis indicates temporal shear stress peaks even far away from walls. The mathematical approach used is the Lattice Boltzmann method. We obtained reasonable results for velocity and shear stress fields. The code is implemented on parallel hardware in order to decrease computation time. Finally, we discuss problems, shortcomings and possible extensions of our approach.

Algorithms↗