Modeling Of Elastic Wave Propagation On Irregular Triangular Grids Using A Finite-Volume Method

We present a finite-volume method for the modeling of wave propagation on irregular triangular grids. This method is based on an integral formulation of the wave equation via Gauss's theorem and on spatial discretization via Delaunay and Dirichlet tessellations. We derive the equations for both SH and P-SV wave propagation in 2-D. The method is of second-order accuracy in time. For uniform triangular grids it is also second-order accurate in space, while the accuracy is first-order in space for nonuniform grids. This method has an advantage over finite-difference techniques because irregular interfaces in a model can be represented more accurately. Moreover, it may be computationally more efficient for complex models.United States. Air Force. Technical Applications Center (Contract FI9628-95-C-0091)United States. Air Force Research Laboratory (Contract FI9628-95-C-0091)Massachusetts Institute of Technology. Earth Resources Laboratory. Reservoir Delineation Consortiu

Simulation Of Elastic Wave Propagation In Models Containing Irregular Interfaces Parameterized On Irregular Grids

Thus study demonstrates the advantages of a recently-developed irregular-grid modeling technique (Nolte, 1996). This technique can model irregular interfaces more accurately than a standard regular-grid finite-difference method. I show this by comparison of both methods for a simple model containing a sloping interface. While the discrete approximation to the sloping interface results in numerical inaccuracies for the finite-difference method, the irregular-grid technique produces superior results. I then show that the method can also be applied to a free surface with irregular topography, suggesting that it may be a valuable alternative to existing finite-difference free-surface algorithms.Massachusetts Institute of Technology. Earth Resources Laboratory. Reservoir Delineation Consortiu

Estimation Of Nonorthogonal Shear Wave Polarizations And Shear Wave Velocities From Four-Component Dipole Logs

Polarizations of split shear waves and flexural borehole waves are most commonly estimated from four-component data using the rotation technique of Alford (1986). This method is limited to the case of the two polarizations being orthogonal to each other. We present a method that is able to handle the case of nonorthogonally polarized waves and, moreover, is computationally more efficient than Alford's technique. Our method is based on the eigenvalue decomposition of an asymmetric matrix and a least-squares minimization of its off-diagonal components. In the case of orthogonally polarized waves, our method will yield exactly the same results as the Alford rotation. We apply our method to a cross-dipole shear-wave logging data set from the Powder River Basin in Wyoming and find that independently rotated source-receiver sets are very consistent with each other in anisotropic sections. After the rotation we compare two methods for estimating the phase velocities of fast and slow waves-a semblance method and homomorphic processing (Ellefsen et al., 1993). We find homomorphic processing to be more reliable due to the dispersive nature of flexural waves.Massachusetts Institute of Technology. Borehole Acoustics and Logging ConsortiumUnited States. Dept. of Energy (Contract DE-FG02-86ER13636

Dispersion Analysis Of Split Flexural Waves

In this paper we first present a technique for measuring dispersion curves from array data, that is both simple and efficient. We demonstrate its performance on both synthetic and field data. We then use the technique to compute dispersion curves for split flexural waves from cross-dipole data from the Powder River Basin in Wyoming. In this data set we consistently observe crossover of the fast and slow flexural waves, an indication of stress-induced anisotropy. Next, we demonstrate the effect that dispersion-curve crossover has on Alford rotation. Finally, we give a procedure for rapidly determining stress-induced anisotropy from crossed-dipole logs.Massachusetts Institute of Technology. Borehole Acoustics and Logging Consortiu

Longitudinal claudin gene expression analyses in canine mammary tissues and thereof derived primary cultures and cell lines

Human and canine mammary tumours show partial claudin expression deregulations. Further, claudins have been used for directed therapeutic approaches. However, the development of claudin targeting approaches requires stable claudin expressing cell lines. This study reports the establishment and characterisation of canine mammary tissue derived cell lines, analysing longitudinally the claudin-1, -3, -4 and -7 expressions in original tissue samples, primary cultures and developed cell lines. Primary cultures were derived from 17 canine mammary tissues: healthy, lobular hyperplasia, simple adenoma, complex adenoma, simple tubular carcinoma, complex carcinoma, carcinoma arising in a benign mixed tumour and benign mixed tissue. Cultivation was performed, if possible, until passage 30. Claudin mRNA and protein expressions were analysed by PCR, QuantiGene Plex Assay, immunocytochemistry and immunofluorescence. Further, cytokeratin expression was analysed immunocytochemically. Cultivation resulted in 11 established cell lines, eight showing epithelial character. In five of the early passages the claudin expressions decreased compared to the original tissues. In general, claudin expressions were diminished during cultivation. Three cell lines kept longitudinally claudin, as well as epithelial marker expressions, representing valuable tools for the development of claudin targeted anti-tumour therapies

PDA Indolylmaleimides Induce Anti-Tumor Effects in Prostate Carcinoma Cell Lines Through Mitotic Death

Castrate resistant prostate cancer in men shares several characteristics with canine prostate cancer (PCa). Due to current insufficient therapies, evaluating novel therapeutic agents for late-stage PCa is of considerable interest for both species. PDA indolylmaleimides showed anticancer effects in several neoplastic cell lines. Herein, a comparative characterization of PDA-66 and PDA-377 mediated effects was performed in human and canine PCa cell lines, which is also the first detailed characterization of these agents on cells derived from solid tumors in general. While PDA-377 showed only weak growth inhibition on human PCa cell lines, PDA-66 inhibited proliferation and induced apoptosis in human and canine cell lines with concentrations in the low micromolar range. Morphological characterization and whole transcriptome sequencing revealed that PDA-66 induces mitotic death through its microtubule-depolymerizing ability. PDA-66 appears to be a worthwhile anti-mitotic agent for further evaluation. The similarities in cellular and molecular response observed in the cell lines of both origins form a solid basis for the use of canine PCa in vivo models to gain valuable interchangeable data to the advantage of both species

Alignment of retention time obtained from multicapillary column gas chromatography used for VOC analysis with ion mobility spectrometry

Multicapillary column (MCC) ion mobility spectrometers (IMS) are increasingly in demand for medical diagnosis, biological applications and process control. In a MCC-IMS, volatile compounds are differentiated by specific retention time and ion mobility when rapid preseparation techniques are applied, e.g. for the analysis of complex and humid samples. Therefore, high accuracy in the determination of both parameters is required for reliable identification of the signals. The retention time in the MCC is the subject of the present investigation because, for such columns, small deviations in temperature and flow velocity may cause significant changes in retention time. Therefore, a universal correction procedure would be a helpful tool to increase the accuracy of the data obtained from a gas-chromatographic preseparation. Although the effect of the carrier gas flow velocity and temperature on retention time is not linear, it could be demonstrated that a linear alignment can compensate for the changes in retention time due to common minor deviations of both the carrier gas flow velocity and the column temperature around the MCC-IMS standard operation conditions. Therefore, an effective linear alignment procedure for the correction of those deviations has been developed from the analyses of defined gas mixtures under various experimental conditions. This procedure was then applied to data sets generated from real breath analyses obtained in clinical studies using different instruments at different measuring sites for validation. The variation in the retention time of known signals, especially for compounds with higher retention times, was significantly improved. The alignment of the retention time—an indispensable procedure to achieve a more precise identification of analytes—using the proposed method reduces the random error caused by small accidental deviations in column temperature and flow velocity significantly

Genetic variants associated with subjective well-being, depressive symptoms, and neuroticism identified through genome-wide analyses

Very few genetic variants have been associated with depression and neuroticism, likely because of limitations on sample size in previous studies. Subjective well-being, a phenotype that is genetically correlated with both of these traits, has not yet been studied with genome-wide data. We conducted genome-wide association studies of three phenotypes: subjective well-being (n = 298,420), depressive symptoms (n = 161,460), and neuroticism (n = 170,911). We identify 3 variants associated with subjective well-being, 2 variants associated with depressive symptoms, and 11 variants associated with neuroticism, including 2 inversion polymorphisms. The two loci associated with depressive symptoms replicate in an independent depression sample. Joint analyses that exploit the high genetic correlations between the phenotypes (|ρ^| ≈ 0.8) strengthen the overall credibility of the findings and allow us to identify additional variants. Across our phenotypes, loci regulating expression in central nervous system and adrenal or pancreas tissues are strongly enriched for association.</p

Genome-wide analysis identifies 12 loci influencing human reproductive behavior.

The genetic architecture of human reproductive behavior-age at first birth (AFB) and number of children ever born (NEB)-has a strong relationship with fitness, human development, infertility and risk of neuropsychiatric disorders. However, very few genetic loci have been identified, and the underlying mechanisms of AFB and NEB are poorly understood. We report a large genome-wide association study of both sexes including 251,151 individuals for AFB and 343,072 individuals for NEB. We identified 12 independent loci that are significantly associated with AFB and/or NEB in a SNP-based genome-wide association study and 4 additional loci associated in a gene-based effort. These loci harbor genes that are likely to have a role, either directly or by affecting non-local gene expression, in human reproduction and infertility, thereby increasing understanding of these complex traits

Формирование эмоциональной культуры как компонента инновационной культуры студентов

Homozygosity has long been associated with rare, often devastating, Mendelian disorders1 and Darwin was one of the first to recognise that inbreeding reduces evolutionary fitness2. However, the effect of the more distant parental relatedness common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity, ROH), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power3,4. Here we use ROH to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts and find statistically significant associations between summed runs of homozygosity (SROH) and four complex traits: height, forced expiratory lung volume in 1 second (FEV1), general cognitive ability (g) and educational attainment (nominal p<1 × 10−300, 2.1 × 10−6, 2.5 × 10−10, 1.8 × 10−10). In each case increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing convincing evidence for the first time that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples5,6, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein (LDL) cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection7, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been