Our analysis of the Deep CFHT M33 variability survey database has uncovered 5 Beat Cepheids (BCs) that are pulsating in the fundamental and first overtone modes. With only the help of stellar pulsation theory and of mass–luminosity (M -L) relations, derived from evolutionary tracks, we can accurately determine the metallicities Z of these stars. The [O/H] metallicity gradient of −0.16 dex/kpc t...

Cellular infection by cytomegalovirus (CMV) is associated with very early G-protein-mediated signal transduction and reprogramming of gene expression. Here we investigated the involvement of human CMV (HCMV)-encoded US27, US28, and UL33 receptors as well as murine CMV-encoded M33 transmembrane (7TM) receptors in host cell signaling mechanisms. HCMV-encoded US27 did not show any constitutive act...

We present the result of a survey for star clusters in M33 using the HST/WFPC2 archive images. We have found 104 star clusters, including 32 new ones, in the images of 24 fields that were not included in the previous studies. Combining these with previous data in the literature, we increase the number of M33 star clusters found in the HST images to 242. We have derived BV I integrated photometr...

We present integrated photometry and color-magnitude diagrams (CMDs) for 24 star clusters in M33, of which 12 were previously uncataloged. These results are based on Advanced Camera for Surveys observations from the Hubble Space Telescope of two fields in M33. Our integrated V magnitudes and V–I colors for the previously identified objects are in good agreement with previously published photome...

The most luminous X-ray source in the Local Group is associated with the nucleus of M33. This source, M33 X-8, appears modulated by ∼ 20% over a ∼ 106 day period, making it unlikely that the combined emission from unresolved sources could explain the otherwise persistent ∼10erg s X-ray flux (Dubus et al. 1997, Hernquist et al. 1991). We present here high resolution UV imaging of the nucleus wit...

Measuring the proper motions and geometric distances of galaxies within the Local Group is very important for our understanding of its history, present state and future. Currently, proper motion measurements using optical methods are limited only to the closest companions of the Milky Way. However, given that VLBI provides the best angular resolution in astronomy and phasereferencing techniques...

The products of the Polycomb group (PcG) of genes are necessary for the maintenance of transcriptional repression of a number of important developmental genes, including the homeotic genes. A two-hybrid screen was used to search for putative new members of the PcG of genes in mammals. We have identified a new Zn finger protein, RYBP, which interacts directly with both Ring1 proteins (Ring1A and...

We present an approach for analysing the morphology and physical properties of Hi features near giant OB associations in M33, in the context of a model whereby the Hi excess arises from photodissociation of the molecular gas in remnants of the parent Giant Molecular Clouds (GMCs). Examples are presented here in the environs of NGC604 and CPSDPZ204, two prominent Hii regions in M33. These are th...

We report the negative results from a search for 6.7 GHz methanol masers in the nearby spiral galaxy M33. We observed 14 GMCs in the central 4 kpc of the Galaxy, and found 3σ upper limits to the flux density of ∼9 mJy in spectral channels having a velocity width of 0.069 kms. By velocity shifting and combining the spectra from the positions observed, we obtain an effective 3σ upper limit on the...