Glueballs, gluerings and gluestars in the d=2+1 SU(N) gauge theory

The 3d gluodynamics which governs the large T quark gluon plasma is studied in the framework of the field correlator method. Field correlators and spacial string tension are derived through the gluelump Green's functions. The glueball spectrum is calculated both in C=-1 as well as in C=+1 sectors, and multigluon bound states in the form of "gluon rings" and "gluon stars" are computed explicitly. Good overall agreement with available lattice data is observed.Comment: 19 page

Antioxidant responses of tolerant and sensitive barley cultivars to boron toxicity

Effect of boron toxicity on antioxidant response of sensitive (Hamidiye) and tolerant (Anadolu) barley (Holgarium vulgar) cultivars was investigated. Eight days old hydroponically grown seedlings were subjected to 5 and 10 mM boric acid treatments for 5 days. Growth parameters (dry-wet weight), protein, proline, MDA, H2O2 contents, membrane damage and activities of superoxide dismutase (SOD). ascorbate peroxidase (APX), catalase (CAT) and glutathion reductase (GR) was evaluated in root and shoot tissues. Compared with controls (no boric acid treatment) boron toxicity resulted in a reduction in root weights and did not cause any significant change in protein contents. Boric acid treatment did not cause significant (P > 0.05) changes in proline and H2O2 contents of both tissues and cultivars. On contrary, NIDA contents and electrolyte leakage exhibited a dose dependent increase in shoots whereas no significant change was observed in root tissues. Higher extend of membrane damage was observed in leaves of the sensitive cultivar. Total SOD, CAT and GR activities in shoot tissue of both cultivars did not change significantly whereas significantly higher APX activities was observed at 10 mM boric acid treatments. Significant increases in total SOD, CAT and decrease in GR activities was observed in roots of the sensitive cultivar. Roots of resistant cultivar, on contrary, exhibited enhanced CAT and decreased APX activity whereas no significant changes was observed in total SOD and GR activities. Our data suggest that. boron toxicity induced membrane damage in barley leaves, do not involve active oxygen species and antioxidant enzyme activity is not a critical factor in boron toxicity tolerance mechanism. To the best of our knowledge, this is the first report on antioxidant response of barley seedlings under boron toxicity. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved

Effects of some agents affecting K+ channels on the isolated mouse vas deferens

Purpose: Effects of agents modifying K+ channel activity on the response of the isolated mouse vas deferens to electrical field stimulation (EFS) were investigated. Methods: The experiments were performed in organ baths containing Krebs solution aerated with 95% O2 and 5% CO2 at the temperature of 25°C. The responses were recorded by isotonic transducers (Ugo Basile, 7006) on the paper of polygraph (Ugo Basile, Gemini 7070). Results: 0.1 Hz EFS evoked reproducible twitches while stimulation at 2 Hz and 5 Hz induced frequency-dependent reproducible contractures. Tetraethylammonium (TEA; 50-500 µM),4-aminopyridine (4-AP; 10-200 µM) and charybdotoxin (CHTX; 0.23 µM) caused enhancements in both twitch and contracture amplitudes in a concentration dependent manner. 1 µM Cromakalim decreased twitch activity without significantly affecting the contractures. Glibenclamide at low concentrations (5 nM, 0.1, 1 and 10 µM) affected neither twitch amplitude nor contracture. At higher concentrations (50 and 100 µM), it caused a considerable inhibition in the responses to EFS. 10 µM GLB potentiated the inhibition produced by 1 µM cromakalim on twitch responses. The inhibitory actions of cromakalim (1 µM) and GLB (10 µM) on the contractile activity deepened in the medium with moderately high potassium (10 or 12 mM). Conclusion: These results suggest that CRO-sensitive K+ channels may be insensitive to blocking effect of GLB and they may have voltage-dependent properties in the mouse vas deferens; the GLB action observed at the higher concentrations may have resulted from other mechanisms responsible for CRO action

Possible roles of nitric oxide and vasoactive intestinal polypeptide on relaxation induced by isoprenaline in isolated muscle strips of the mouse gastric fundus.

PubMedID: 8585392The possible role of nitric oxide (NO) and vasoactive intestinal polypeptide on isoprenaline-induced relaxation of the mouse longitudinal gastric fundal strips precontracted with 5.4 x 10(-7) M carbachol was investigated. Isoprenaline (5 x 10(-7) M, 10(-6) M and 5 x 10(-6) M) produced a concentration-dependent relaxations. NG-nitro L-arginine (10(-4) M) partly inhibited isoprenaline-induced relaxation. The inhibitory action of NG-nitro L-arginine was reversed by 4 x 10(-4) M L-arginine but not by 4 x 10(-4) M D-arginine. NG-nitro L-arginine (10(-4) M) did not affect the relaxation caused by sodium nitroprusside (10(-6) M). Vasoactive intestinal polypeptide antibody 7913 (1:160 dilution) partly inhibited isoprenaline-induced relaxation. This inhibition was greater on the response to the higher isoprenaline concentration (5 x 10(-6) M) than to the lower concentration (10(-6) M). The combination of vasoactive intestinal polypeptide antibody and NG-nitro L-arginine significantly enhanced the inhibition on 10(-6) M isoprenaline action. These results suggest that nitric oxide and vasoactive intestinal polypeptide may partly contribute to the relaxation induced by isoprenaline in the mouse gastric fundus precontracted with carbachol

A deconvolution technique to correct deep images of galaxies from instrumental scattered light

Deep imaging of the diffuse light that is emitted by stellar fine structures and outer halos around galaxies is often now used to probe their past mass assembly. Because the extended halos survive longer than the relatively fragile tidal features, they trace more ancient mergers. We use images that reach surface brightness limits as low as 28.5−29 mag arcsec-2 (g-band) to obtain light and color profiles up to 5–10 effective radii of a sample of nearby early-type galaxies. These were acquired with MegaCam as part of the CFHT MATLAS large programme. These profiles may be compared to those produced using simulations of galaxy formation and evolution, once corrected for instrumental effects. Indeed they can be heavily contaminated by the scattered light caused by internal reflections within the instrument. In particular, the nucleus of galaxies generates artificial flux in the outer halo, which has to be precisely subtracted. We present a deconvolution technique to remove the artificial halos that makes use of very large kernels. The technique, which is based on PyOperators, is more time efficient than the model-convolution methods that are also used for that purpose. This is especially the case for galaxies with complex structures that are hard to model. Having a good knowledge of the point spread function (PSF), including its outer wings, is critical for the method. A database of MegaCam PSF models corresponding to different seeing conditions and bands was generated directly from the deep images. We show that the difference in the PSFs in different bands causes artificial changes in the color profiles, in particular a reddening of the outskirts of galaxies having a bright nucleus. The method is validated with a set of simulated images and applied to three representative test cases: NGC 3599, NGC 3489, and NGC 4274, which exhibits a prominent ghost halo for two of them. This method successfully removes this