In species with indeterminate growth, age-related size variation of reproductive competitors within each sex is often high. This selects for divergence in reproductive tactics of same-sex competitors, particularly in males. Where alternative tactics are fixed for life, the causality of tactic choice is often unclear. In the African cichlid Lamprologus callipterus, large nest males collect and p...

Recent spectroscopic and morphological observational studies of galaxies around NGC 1399 in the Fornax Cluster (Drinkwater et al. 2000b) have discovered several ‘ultra-compact dwarf’ galaxies with intrinsic sizes of ∼ 100 pc and absolute B band magnitudes ranging from −13 to −11 mag. In order to elucidate the origin of these enigmatic objects, we perform numerical simulations on the dynamical e...

Studierstube and DWARF are modular Augmented Reality frameworks, each with distinct advantages in different application areas. Both can easily be extended by adding new components. In this case study we show how new components can act as a bridge between the frameworks. By facilitating the exchange of basic data types such as pose and user input, the frameworks become interoperable. This allows...

We present optical (6500-9200Å) spectroscopy of eight cool dwarfs detected in a 231 square degree “Mini-survey” of the Deep NEar Infrared Survey (DENIS) data. We are able to confirm that the spectral types derived from the Mini-survey infrared spectroscopy are meaningful. We provide a spectral sequence which extends beyond the M-dwarf range and into the proposed “L” class of dwarfs. The dominan...

We report the results of spectroscopic observations, obtained with the GEMINI MultiObject Spectrograph, of 8 planetary nebulae (PNe) in the dwarf spheroidal (dSph) galaxy NGC 147, a companion of M 31. The physico-chemical properties of the six brightest PNe (Corradi et. al. 2005) were derived using both the empirical icf method and photoionization modelling with cloudy. Different aspects of the...

We investigate the effects of gravity on the infrared spectra of objects around the M dwarf to brown dwarf transition. We focus on observations of the very low-mass objects TVLM 513–46546 and GJ 569B from 1 to 2.5 μm. These objects have very similar spectral types and colours but they differ by more than a magnitude in luminosity; this indicates that their surface gravities differ by around 0.5...

Globular star clusters are among the first stellar populations to have formed in the Milky Way, and thus only a small sliver of their initial spectrum of stellar types are still burning hydrogen on the main-sequence today. Almost all of the stars born with more mass than 0.8 M⊙ have evolved to form the white dwarf cooling sequence of these systems, and the distribution and properties of these r...

We explore the consequences of a magnetic dynamo origin for the viscosity in accretion discs, for the structure and evolution of discs in dwarf nova systems. We propose that the rapid cooling that sets in at the end of a dwarf nova eruption acts to inhibit the Balbus-Hawley instability, and thereby to quench dynamo action and so reduce disc viscosity. We demonstrate that a modi ed disc instabil...

The aim of this study was to analyze the effects on growth and muscle development during the growing period of the sex-linked dwarf gene in the background of a Taiwan Country chicken strain, L2, selected for egg production. Eight crossbred males, heterozygous for the DW*DW mutation, were each backcrossed to six females of the L2 strain to produce two genotypes of BC females, either normal (DW*N...