42 resultados para Direct Sum of Cyclics


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A hypnotic induction technique was used to facilitate direct observation of multiple tics in a typically developing teenager in a home setting. A comprehensive habit reversal program then was implemented, including awareness training, competing response training, relaxation training, self-monitoring, social support and contingency management. Duration of relaxation was then self-monitored using a changing criterion design. The procedure eliminated multiple tics and achieved long-term maintenance of treatment gains. Implications for assessing and treating tics are discussed.

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We present differential x-ray scattering cross sections for a radiatively heated plasma showing overall consistency, in both form and absolute value, with theoretical simulations. In particular, the evolution of the plasma from a strongly coupled high density phase to a lower density weakly coupled phase is quite clearly shown in both experiment and simulation. The success of this experiment shows that x-ray scattering has the potential to become an extremely useful diagnostic technique for dense plasma physics.

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The Yarkovsky-O'Keefe-Radzievskii-Paddack effect is believed to alter the spin states of small bodies in the solar system. However, evidence for the effect has so far been indirect. Here we report precise optical photometric and radar observations acquired over four years of a small near-Earth asteroid (54509) 2000 PH5. We find the asteroid has been continuously increasing its rotation rate omega over this period by domega/dt = (2.0+/- 0.2) x 10-4 deg/day2. We simulated the close Earth approaches from 2001-2005, showing that gravitational torques cannot explain the observed spin-rate increase. Dynamical simulations also suggest that 2000 PH5 may reach a rotation period of ~20 seconds towards the end of its expected lifetime

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In this Letter we report on a near collective x-ray scattering experiment on shock-compressed targets. A highly coupled Al plasma was generated and probed by spectrally resolving an x-ray source forward scattered by the sample. A significant reduction in the intensity of the elastic scatter was observed, which we attribute to the formation of an incipient long-range order. This speculation is confirmed by x-ray scattering calculations accounting for both electron degeneracy and strong coupling effects. Measurements from rear side visible diagnostics are consistent with the plasma parameters inferred from x-ray scattering data. These results give the experimental evidence of the strongly coupled ionic dynamics in dense plasmas.

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Let A be a self-adjoint operator on a Hilbert space. It is well known that A admits a unique decomposition into a direct sum of three self-adjoint operators A(p), A(ac) and A(sc) such that there exists an orthonormal basis of eigenvectors for the operator A(p) the operator A(ac) has purely absolutely continuous spectrum and the operator A(sc) has purely singular continuous spectrum. We show the existence of a natural further decomposition of the singular continuous component A c into a direct sum of two self-adjoint operators A(sc)(D) and A(sc)(ND). The corresponding subspaces and spectra are called decaying and purely non-decaying singular subspaces and spectra. Similar decompositions are also shown for unitary operators and for general normal operators.

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Catalytic systems for the direct production of hydrogen peroxide from hydrogen and oxygen are investigated, and the factors which make a successful process identified. The use of low metal loadings, an organic co-solvent (such as ethanol) and reduced palladium as the catalytic metal all lead to good activity and selectivity. (C) 2002 Elsevier Science B.V. All rights reserved.

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BACKGROUND & AIMS: The transcription Factor RUNX3 is a gastric tumor suppressor. Tumorigenic Runx3(-/-) gastric epithelial cells attach weakly to each other, compared with nontumorigenic Runx3(+/+) cells. We alined to identify RUNX3 target genes that promote cell-cell contact to Improve our understanding of RUNX3's role in Suppressing gastric carcinogenesis. METHODS: We compared gene expression profiles of Runx3(+/+) and Runx3(-/-) cells and observed down-regulation of genes associated with cell-cell adhesion in Runx3(-/-) cells. Reporter, mobility shift, and chromatin immunoprecipitation assays were used to examine the regulation of these genes by RUNX3. Tumorigenesis assays and immunohistologic, analyses of human gastric tumors were performed to confirm the role of the candidate genes ill gastric tumor development. RESULTS: Mobility shift and chromatin immunoprecipitation assays revealed that the promoter activity of the gene that encodes the tight Junction protein claudin-1 was up-regulated via the binding of RUNX3 to the RUNX consensus sites. The tumorigenicity of gastric epithelial cells From Runx3(-/-) mice was significantly reduced by restoration of claudin-1 expression, whereas knockdown of claudin-1. increased the tumorigenicity of human gastric cancer cells. Concomitant expression of RUNX3 and claudin-1 was observed in human normal gastric epithelium and cancers. CONCLUSIONS: The tight junction protein claudin-1 has gastric tumor suppressive activity and is a direct transcriptional target of RUNX3. Claudin-1 is down-regulated during the epithelial-mesenchymal transition; RUNX3 might therefore act as a tumor suppressor to antagonize the epithelial-mesenchymal transition.

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The t(11; 17)(q23;q21) translocation is associated with a retinoic acid (RA)-insensitive form of acute promyelocytic leukemia (APL), involving the production of reciprocal fusion proteins, promyelocytic leukemia zinc finger-retinoic acid receptor alpha (PLZF-RAR alpha) and RAR alpha-PLZF. Using a combination of chromatin immuno-precipitation promotor arrays (ChIP-chip) and gene expression profiling, we identify novel, direct target genes of PLZF-RAR alpha that tend to be repressed in APL compared with other myeloid leukemias, supporting the role of PLZF-RAR alpha as an aberrant repressor in APL. In primary murine hematopoietic progenitors, PLZF-RAR alpha promotes cell growth, and represses Dusp6 and Cdkn2d, while inducing c-Myc expression, consistent with its role in leukemogenesis. PLZF-RAR alpha binds to a region of the c-MYC promoter overlapping a functional PLZF site and antagonizes PLZF-mediated repression, suggesting that PLZF-RAR alpha may act as a dominant-negative version of PLZF by affecting the regulation of shared targets. RA induced the differentiation of PLZF-RAR alpha-transformed murine hematopoietic cells and reduced the frequency of clonogenic progenitors, concomitant with c-Myc down-regulation. Surviving RA-treated cells retained the ability to be replated and this was associated with sustained c-Myc expression and repression of Dusp6, suggesting a role for these genes in maintaining a self-renewal pathway triggered by PLZF-RAR alpha. (Blood. 2009; 114: 5499-5511)

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Inorganic polyphosphate (polyP) is increasingly being recognized as an important phosphorus sink within the environment, playing a central role in phosphorus exchange and phosphogenesis. Yet despite the significant advances made in polyP research there is a lack of rapid and efficient analytical approaches for the quantification of polyP accumulation in microbial cultures and environmental samples. A major drawback is the need to extract polyP from cells prior to analysis. Due to extraction inefficiencies this can lead to an underestimation of both intracellular polyP levels and its environmental pool size: we observed 23-58% loss of polyP using standard solutions and current protocols. Here we report a direct fluorescence based DAPI assay system which removes the requirement for prior polyP extraction before quantification. This increased the efficiency of polyP detection by 28-55% in microbial cultures suggesting quantitative measurement of the intracellular polyP pool. It provides a direct polyP assay which combines quantification capability with technical simplicity. This is an important step forward in our ability to explore the role of polyP in cellular biology and biogeochemical nutrient cycling.

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Despite a clear link between ataxia-telangiectasia mutated (ATM)-dependent phosphorylation of p53 and cell cycle checkpoint control, the intracellular biology and subcellular localization of p53 phosphoforms during the initial sensing of DNA damage is poorly understood. Using GO-G, confluent primary human diploid fibroblast cultures, we show that endogenous p53, phosphorylated at Ser(15) (p53(Ser15)), accumulates as discrete, dose-dependent and chromatin-bound foci within 30 minutes following induction of DNA breaks or DNA base damage. This biologicafly distinct subpool of p53(Ser15) is ATM dependent and resistant to 26S-proteasomal degradation. p53(Ser15) colocalizes and coimmunoprecipitates with gamma-H2AX with kinetics similar to that of biochemical DNA double-strand break (DNA-dsb) rejoining. Subnuclear micro-beam irradiation studies confirm p53 S,,15 is recruited to sites of DNA damage containing gamma-H2AX, ATM(Ser1981), and DNA-PKcs(Thr2609) in vivo. Furthermore, studies using isogenic human and murine cells, which express Ser(15) or Ser(18) phosphomutant proteins, respectively, show defective nuclear foci formation, decreased induction of p21(WAF) decreased gamma-H2AX association, and altered DNA-dsb kinetics following DNA damage. Our results suggest a unique biology for this p53 phosphoform in the initial steps of DNA damage signaling and implicates ATM-p53 chromatin-based interactions as mediators of cell cycle checkpoint control and DNA repair to prevent carcinogenesis. (Cancer Res 2005; 65(23): 10810-21).