Time and M-theory

We review our recent proposal for a background independent formulation of a holographic theory of quantum gravity. The present review incorporates the necessary background material on geometry of canonical quantum theory, holography and spacetime thermodynamics, Matrix theory, as well as our specific proposal for a dynamical theory of geometric quantum mechanics, as applied to Matrix theory. At the heart of this review is a new analysis of the conceptual problem of time and the closely related and phenomenologically relevant problem of vacuum energy in quantum gravity. We also present a discussion of some observational implications of this new viewpoint on the problem of vacuum energy.Comment: 86 pages, 5 figures, LaTeX, typos fixed, references added, and Sec. 6.2 revised; invited review for Int. J. Mod. Phys.

Parsec-scale radio structures in the nuclei of four Seyfert galaxies

We present 18-cm radio maps of four Seyfert nuclei, Mrk 1, Mrk 3, Mrk 231 and Mrk 463E, made with the European VLBI Network (EVN). Linear radio structures are present in three out of four sources on scales of ~100 pc to ~1 kpc, and the 20-mas beam of the EVN enables us to resolve details within the radio structures on scales of <10 pc. Mrk 3 was also imaged using MERLIN and the data combined with the EVN data to improve the sensitivity to extended emission. We find an unresolved flat-spectrum core in Mrk 3, which we identify with the hidden Seyfert 1 nucleus in this object, and we also see marked differences between the two highly-collimated radio jets emanating from the core. The western jet terminates in a bright hotspot and resembles an FRII radio structure, whilst the eastern jet has more in common with an FRI source. In Mrk 463E, we use the radio and optical structure of the source to argue that the true nucleus lies approximately 1 arcsec south of the position of the radio and optical brightness peaks, which probably represent a hotspot at the working surface of a radio jet. The EVN data also provide new evidence for a 100-pc radio jet powering the radio source in the Type 1 nucleus of Mrk 231. However, the Seyfert 2 galaxy Mrk 1 shows no evidence for radio jets down to the limits of resolution (~10 pc). We discuss the range of radio source size and morphology which can occur in the nuclei of Seyfert galaxies and the implications for Seyfert unification schemes and for radio surveys of large samples of objects.Comment: 23 pages, 7 postscript figures (supplied as separate files), uses AAS aaspp4 LaTeX style file, to appear in the 10 June 1999 issue of The Astrophysical Journa

Diastereoselective Hydrogenation in the Preparation of Fine Chemicals

Heterogeneous catalytic diastereoselective hydrogenation is reviewed with a special emphasis on its application in the preparation of fine chemical

Optical off-nuclear spectra of quasar hosts and radio galaxies

We present optical (~3200A to ~9000A) off-nuclear spectra of 26 powerful active galaxies in the redshift range 0.1 < z < 0.3, obtained with the Mayall and William Herschel 4-meter class telescopes. The sample consists of radio-quiet quasars, radio-loud quasars (all with -23 > M_V > -26) and radio galaxies of Fanaroff & Riley Type II (with extended radio luminosities and spectral indices comparable to those of the radio-loud quasars). The spectra were all taken approximately 5 arcseconds off-nucleus, with offsets carefully selected so as to maximise the amount of galaxy light falling into the slit, whilst simultaneously minimising the amount of scattered nuclear light. The majority of the resulting spectra appear to be dominated by the integrated stellar continuum of the underlying galaxies rather than by light from the non-stellar processes occurring in the active nuclei, and in many cases a 4000A break feature can be identified. The individual spectra are described in detail, and the importance of the various spectral components is discussed. Stellar population synthesis modelling of the spectra will follow in a subsequent paper (Nolan et al. 2000).Comment: 23 pages, LaTeX, uses MNRAS style file, incorporates 71 postscript figures, to be published in MNRAS. Contact author: [email protected]

An attempt at evaluating the direction and tempo of the transport infrastructure transformation in new EU members and EU aspiring countries

The paper presents the diversity of the transport infrastructure development in new EU members and countries aspiring to that organisation. Directions and the tempo of this phenomenon transformation are considered, as well. A statistical analysis is employed to characterise multivariate phenomenon by creation of an aggregate variable. The methodology of building up this measure encompasses normalisation process of diagnostic characteristics (zeroed unitarisation). The outcome of the research is a typology of countries according to the developmental level of an issue under investigation. Subsequently the research focuses on the prognosis of directions of the infrastructure transformation in individual countries. The forecast includes the time estimate of developmental disproportions equalization.multivariate analysis, transport infrastructure

Effect of quercetin and role of nitric oxide pathway in chloroquine-induced scratching

Nitric oxide (NO) is an abundant mediator which is demonstrated to be involved in pruritus. Assuming that the increased NO also mediates chloroquine-induced pruritus, which is a frequent complication seen in the chronic chloroquine treatment, the current study aimed to investigate the effect of quercetin and the role of NO in chloroquine-induced pruritus in C57BL/6 mice. Model was created with subcutaneous chloroquine (400µg/site) injection to the nape of the mice. Effect of quercetin and role of NO were investigated with administration of quercetin, and co-administration with L-NAME, 7-NI and L-arginine before chloroquine injection. Locomotor activity was assessed by activity cage and number of the scratching bouts after chloroquine injection was recorded for 30 minutes. Our results show that quercetin significantly reduced scratching bouts at the doses of 10, 20, 40 and 80 mg/kg. Locomotor activity was decreased at the 40 and 80 mg/kg doses of quercetin. Additionally, decrease of the number of scratching bouts by quercetin prevented by L-arginine treatment, while L-NAME and 7-NI enhanced the anti-pruritic effect of sub-effective doses of quercetin. Therefore, our study demonstrated that acute injection of quercetin significantly diminished chloroquine-induced scratching behavior, and this effect is partly mediated by inhibition of neuronal nitric oxide synthase enzyme