DNS of vertical plane channel flow with finite-size particles: Voronoi analysis, acceleration statistics and particle-conditioned averaging

We have performed a direct numerical simulation of dilute turbulent particulate flow in a vertical plane channel, fully resolving the phase interfaces. The flow conditions are the same as those in the main case of "Uhlmann, M., Phys. Fluids, vol. 20, 2008, 053305", with the exception of the computational domain length which has been doubled in the present study. The statistics of flow and particle motion are not significantly altered by the elongation of the domain. The large-scale columnar-like structures which had previously been identified do persist and they are still only marginally decorrelated in the prolonged domain. Voronoi analysis of the spatial particle distribution shows that the state of the dispersed phase can be characterized as slightly more ordered than random tending towards a homogeneous spatial distribution. It is also found that the p.d.f.'s of Lagrangian particle accelerations for wall-normal and spanwise directions follow a lognormal distribution as observed in previous experiments of homogeneous flows. The streamwise component deviates from this law presenting significant skewness. Finally, a statistical analysis of the flow in the near field around the particles reveals that particle wakes present two regions, a near wake where the velocity deficit decays as 1/x and a far wake with a decay of approximately 1/(x*x).Comment: accepted for publication in Int. J. Multiphase Flo

New angiogenic regulators produced by TAMs: perspective for targeting tumor angiogenesis

Angiogenesis is crucial to the supply of a growing tumor with nutrition and oxygen. Inhibition of angiogenesis is one of the main treatment strategies for colorectal, lung, breast, renal, and other solid cancers. However, currently applied drugs that target VEGF or receptor tyrosine kinases have limited efficiency, which raises a question concerning the mechanism of patient resistance to the already developed drugs. Tumor-associated macrophages (TAMs) were identified in the animal tumor models as a key inducer of the angiogenic switch. TAMs represent a potent source not only for VEGF, but also for a number of other pro-angiogenic factors. Our review provides information about the activity of secreted regulators of angiogenesis produced by TAMs. They include members of SEMA and S100A families, chitinase-like proteins, osteopontin, and SPARC. The COX-2, Tie2, and other factors that control the pro-angiogenic activity of TAMs are also discussed. We highlight how these recent findings explain the limitations in the efficiency of current anti-angiogenic therapy. Additionally, we describe genetic and posttranscriptional mechanisms that control the expression of factors regulating angiogenesis. Finally, we present prospects for the complex targeting of the pro-angiogenic activity of TAMs

Methionine restriction extends lifespan of \u3ci\u3eDrosophila melanogaster\u3c/i\u3e under conditions of low amino-acid status

Reduced methionine (Met) intake can extend lifespan of rodents; however, whether this regimen represents a general strategy for regulating aging has been controversial. Here we report that Met restriction extends lifespan in both fruit flies and yeast, and that this effect requires low amino-acid status. Met restriction in Drosophila mimicks the effect of dietary restriction and is associated with decreased reproduction. However, under conditions of high amino-acid status, Met restriction is ineffective and the trade-off between longevity and reproduction is not observed. Overexpression of InRDN or Tsc2 inhibits lifespan extension by Met restriction, suggesting the role of TOR signalling in the Met control of longevity. Overall, this study defines the specific roles of Met and amino-acid imbalance in aging and suggests that Met restiction is a general strategy for lifespan extension

Realization of the Vilnius photometric system for CCD-observations of selected sky areas at the Andrushivka Astronomical Observatory

We describe a set of glass UPXYZVS filters of the Vilnius photometric system of the Andrushivka Astronomical Observatory in Zhytomyr Region (Ukraine) [7]. They are installed at the Zeiss-600 Cassegrain reflector together with the 15-bit 1024×1024 CCD-camera S1C-017. The response curves of instrumental photometric systems are presented and a comparison of them with a standard system are analysed. Test observations in the Vilnius system of the star cluster IC 4665 with the Andrushivka filters were carried out in May–June 2003. The MIDAS/ROMAFOT and ASTROIMAGE software is adapted for digital processing of CCD-images of stellar fields. Comprehensive ground-based observations are being planned to design a catalogue of primary UPXYZVS CCD-standards in selected areas of the sky where are with radio sources, globular and open clusters, etc

Pattern of expression of immune- and stroma-associated genes in blood of mice with experimental B16 melanoma

The interaction between malignant and stromal cells represents a major cross-talk pathway upon carcinogenesis. Cellular elements of the reactive tumor stroma are a heterogeneous population which are represented specifically by cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAM). It is not known whether expression of CAF- and TAM-associated genes could be detected in the peripheral blood of cancer patients to monitor a course of disease. The aim of the study was to assess the relative expression (RE) of cancer-related genes in peripheral blood of mice with experimental melanoma. Quantitative PCR was used to determine RE of 15 genes in the blood of C57BL/6j control mice and mice with injected B16 melanoma cells. The Kruskal-Wallis and the Fischer exact tests with correction on multiple comparisons, according­ to the Benjamini-Hochberg procedure with FDR = 0.2 were used for statistical analysis. Analysis of 15 immune and stromal markers RE showed differentiated expression of several CAF and TAM markers in mice with experimental melanoma in comparison with the control animals. Thus, CAF markers Acta2, Cxcl14, Fap and TAM markers Cd68, Ccl22 and Ccl17 were significantly upregulated, while Cd4, Cd3 were downregulated. This, together with increased expression of Cox-2 suggested a stable immunosuppressive state of mice with experimental melanomas. The results of the study showed that potential markers of cancer-associated fibroblasts and tumor-associated macrophages in peripheral blood of mice with experimental melanoma could be used for non-invasive detection of melanoma cell progression

Effect of the pore space on the strength of ceramics

The results of studies of the effect of the pore space and microcracks on ceramic strength are presented. © 2012 Springer Science+Business Media New York

Elastic turbulence in curvilinear flows of polymer solutions

Following our first report (A. Groisman and V. Steinberg, \sl Nature $\bf 405$, 53 (2000)) we present an extended account of experimental observations of elasticity induced turbulence in three different systems: a swirling flow between two plates, a Couette-Taylor (CT) flow between two cylinders, and a flow in a curvilinear channel (Dean flow). All three set-ups had high ratio of width of the region available for flow to radius of curvature of the streamlines. The experiments were carried out with dilute solutions of high molecular weight polyacrylamide in concentrated sugar syrups. High polymer relaxation time and solution viscosity ensured prevalence of non-linear elastic effects over inertial non-linearity, and development of purely elastic instabilities at low Reynolds number (Re) in all three flows. Above the elastic instability threshold, flows in all three systems exhibit features of developed turbulence. Those include: (i)randomly fluctuating fluid motion excited in a broad range of spatial and temporal scales; (ii) significant increase in the rates of momentum and mass transfer (compared to those expected for a steady flow with a smooth velocity profile). Phenomenology, driving mechanisms, and parameter dependence of the elastic turbulence are compared with those of the conventional high Re hydrodynamic turbulence in Newtonian fluids.Comment: 23 pages, 26 figure

Aberrant expression of selenium-containing glutathione peroxidases in clear cell renal cell carcinomas

Aim: To find putative diagnostic markers for clear cell renal cell carcinomas (ccRCC). Material and methods: Quantitative polymerase chain reaction (Q-PCR), bisulfite treatment, methylation-specific PCR, analysis on cBioPortal for Cancer Genomics. Results: We have found that expression of GPX 1, GPX3, and GPX4 genes was decreased in ccRCC. We have shown that the number of alanine (GCG) repeats at the amino terminus of the GPX1 protein is variable. It was reported earlier that an allele that possess 5 alanine repeats is associated with the increased cancer risk. According to the obtained data, the allele with the 5 alanine repeats was also present in a group of healthy donors. Moreover, the frequency of alleles with repeats was similar among ccRCC patients and healthy individuals. We found that decreased expression of GPXs genes was not associated with promoter methylation. To provide other explanation, an analysis on the gene copy number was performed. We have found the heterozygous deletions for GPX1 gene, amplification for GPX3 gene, and no change in gene copy number for GPX4. Conclusions: Our data support the hypothesis that GPX1, GPX3, and GPX4 genes may play a role in ccRCC cancerogenesis and therefore they might be considered as putative diagnostic markers for ccRCC. Key Words: clear cell renal cell carcinomas, selenium-containing GPXs, genetic and epigenetic regulation

Methionine restriction extends lifespan of Drosophila melanogaster under conditions of low amino acid status

Reduced methionine (Met) intake can extend lifespan of rodents, but whether this regimen represents a general strategy for regulating aging has been controversial. Here we report that Met restriction extends lifespan in both fruit flies and yeast, and that this effect requires low amino acid status. Met restriction in Drosophila mimicks the effect of dietary restriction and is associated with decreased reproduction. However, under conditions of high amino acid status, Met restriction is ineffective and the trade-off between longevity and reproduction is not observed. Overexpression of InRDN or Tsc2 inhibits lifespan extension by Met restriction, suggesting the role of TOR signaling in the Met control of longevity. Overall, this study defines the specific roles of Met and amino acid imbalance in aging and suggests that Met restiction is a general strategy for lifespan extension