269 research outputs found

    Shape description and matching using integral invariants on eccentricity transformed images

    Get PDF
    Matching occluded and noisy shapes is a problem frequently encountered in medical image analysis and more generally in computer vision. To keep track of changes inside the breast, for example, it is important for a computer aided detection system to establish correspondences between regions of interest. Shape transformations, computed both with integral invariants (II) and with geodesic distance, yield signatures that are invariant to isometric deformations, such as bending and articulations. Integral invariants describe the boundaries of planar shapes. However, they provide no information about where a particular feature lies on the boundary with regard to the overall shape structure. Conversely, eccentricity transforms (Ecc) can match shapes by signatures of geodesic distance histograms based on information from inside the shape; but they ignore the boundary information. We describe a method that combines the boundary signature of a shape obtained from II and structural information from the Ecc to yield results that improve on them separately

    Multi-messenger observations of a binary neutron star merger

    Get PDF
    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    Search for Dark Matter and Supersymmetry with a Compressed Mass Spectrum in the Vector Boson Fusion Topology in Proton-Proton Collisions at root s=8 TeV

    Get PDF
    Peer reviewe

    The effects of phenoxodiol on the cell cycle of prostate cancer cell lines

    Get PDF
    Background: Prostate cancer is associated with a poor survival rate. The ability of cancer cells to evade apoptosis and exhibit limitless replication potential allows for progression of cancer from a benign to a metastatic phenotype. The aim of this study was to investigate in vitro the effect of the isoflavone phenoxodiol on the expression of cell cycle genes. Methods: Three prostate cancer cell lines-LNCaP, DU145, and PC3 were cultured in vitro, and then treated with phenoxodiol (10 μM and 30 μM) for 24 and 48 h. The expression of cell cycle genes p21WAF1, c-Myc, Cyclin-D1, and Ki-67 was investigated by Real Time PCR. Results: Here we report that phenoxodiol induces cell cycle arrest in the G1/S phase of the cell cycle, with the resultant arrest due to the upregulation of p21WAF1 in all the cell lines in response to treatment, indicating that activation of p21WAF1 and subsequent cell arrest was occurring via a p53 independent manner, with induction of cytotoxicity independent of caspase activation. We found that c-Myc and Cyclin-D1 expression was not consistently altered across all cell lines but Ki-67 signalling expression was decreased in line with the cell cycle arrest. Conclusions: Phenoxodiol demonstrates an ability in prostate cancer cells to induce significant cytotoxicity in cells by interacting with p21WAF1 and inducing cell cycle arrest irrespective of p53 status or caspase pathway interactions. These data indicate that phenoxodiol would be effective as a potential future treatment modality for both hormone sensitive and hormone refractory prostate cancer

    Low-energy Observables and General Gauge Mediation in the MSSM and NMSSM

    Full text link
    We study constraints on the general gauge mediation (GGM) parameter space arising from low-energy observables in the MSSM and NMSSM. Specifically, we look at the dependence of the spectra and observables on the correlation function ratios in the hidden sector where supersymmetry is presumably broken. Since these ratios are not a priori constrained by theory, current results from the muon anomalous magnetic moment and flavor physics can potentially provide valuable intuition about allowed possibilities. It is found that the muon anomalous magnetic moment and flavor-physics observables place significant constraints on the GGM parameter space with distinct dependences on the hidden sector correlation function ratios. The particle spectra arising in GGM, with the possibility of different correlation function ratios, is contrasted with common intuition from regular gauge mediation (RGM) schemes (where the ratios are always fixed). Comments are made on precision gauge coupling unification, topography of the NLSP space, correlations of the muon anomalous magnetic moment with other observables, and approximate scaling relations in sparticle masses with respect to the high-scale correlation function ratios.Comment: 43 pages, 16 figures. Typos corrected, updated references, acknowledgements and minor changes in expositio

    Effects of Imatinib Mesylate (Gleevec) on Human Islet NF-kappaB Activation and Chemokine Production In Vitro

    Get PDF
    Imatinib Mesylate (Gleevec) is a drug that potently counteracts diabetes both in humans and in animal models for human diabetes. We have previously reported that this compound in human pancreatic islets stimulates NF-κB signaling and islet cell survival. The aim of this study was to investigate control of NF-κB post-translational modifications exerted by Imatinib and whether any such effects are associated with altered islet gene expression and chemokine production in vitro.Human islets were either left untreated or treated with Imatinib for different timepoints. IκB-α and NF-κB p65 phosphorylation and methylation were assessed by immunoblot analysis. Islet gene expression was assessed using a commercial Pathway Finder microarray kit and RT-PCR. Islet chemokine production was determined by flow cytometric bead array analysis.Human islet IκB-α and Ser276-p65 phosphorylation were increased by a 20 minute Imatinib exposure. Methylation of p65 at position Lys221 was increased after 60 min of Imatinib exposure and persisted for 3 hours. Microarray analysis of islets exposed to Imatinib for 4 hours revealed increased expression of the inflammatory genes IL-4R, TCF5, DR5, I-TRAF, I-CAM, HSP27 and IL-8. The islet release of IL-8 was augmented in islets cultured over night in the presence of Imatinib. Following 30 hours of Imatinib exposure, the cytokine-induced IκB-α and STAT1 phosphorylation was abolished and diminished, respectively. The cytokine-induced release of the chemokines MIG and IP10 was lower in islets exposed to Imatinib for 30 hours.Imatinib by itself promotes a modest activation of NF-κB. However, a prolonged exposure of human islets to Imatinib is associated with a dampened response to cytokines. It is possible that Imatinib induces NF-κB preconditioning of islet cells leading to lowered cytokine sensitivity and a mitigated islet inflammation

    A novel a-L-Arabinofuranosidase of Family 43 Glycoside Hydrolase (Ct43Araf ) from Clostridium thermocellum

    Get PDF
    Articles in International JournalsThe study describes a comparative analysis of biochemical, structural and functional properties of two recombinant derivatives from Clostridium thermocellum ATCC 27405 belonging to family 43 glycoside hydrolase. The family 43 glycoside hydrolase encoding a-L-arabinofuranosidase (Ct43Araf) displayed an N-terminal catalytic module CtGH43 (903 bp) followed by two carbohydrate binding modules CtCBM6A (405 bp) and CtCBM6B (402 bp) towards the C-terminal. Ct43Araf and its truncated derivative CtGH43 were cloned in pET-vectors, expressed in Escherichia coli and functionally characterized. The recombinant proteins displayed molecular sizes of 63 kDa (Ct43Araf) and 34 kDa (CtGH43) on SDS-PAGE analysis. Ct43Araf and CtGH43 showed optimal enzyme activities at pH 5.7 and 5.4 and the optimal temperature for both was 50uC. Ct43Araf and CtGH43 showed maximum activity with rye arabinoxylan 4.7 Umg21 and 5.0 Umg21, respectively, which increased by more than 2-fold in presence of Ca2+ and Mg2+ salts. This indicated that the presence of CBMs (CtCBM6A and CtCBM6B) did not have any effect on the enzyme activity. The thin layer chromatography and high pressure anion exchange chromatography analysis of Ct43Araf hydrolysed arabinoxylans (rye and wheat) and oat spelt xylan confirmed the release of L-arabinose. This is the first report of a-L-arabinofuranosidase from C. thermocellum having the capacity to degrade both pnitrophenol- a-L-arabinofuranoside and p-nitrophenol-a-L-arabinopyranoside. The protein melting curves of Ct43Araf and CtGH43 demonstrated that CtGH43 and CBMs melt independently. The presence of Ca2+ ions imparted thermal stability to both the enzymes. The circular dichroism analysis of CtGH43 showed 48% b-sheets, 49% random coils but only 3% a-helices
    corecore