Steady free-surface flow over spatially periodic topography

Two-dimensional free-surface flow over a spatially periodic channel bed topography is examined using a steady periodically forced Korteweg-de Vries equation. The existence of new forced solitary-type waves with periodic tails is demonstrated using recently developed non-autonomous dynamical-systems theory. Bound states with two or more co-existing solitary waves are also identified. The solution space for varying amplitude of forcing is explored using a numerical method. A rich bifurcation structure is uncovered and shown to be consistent with an asymptotic theory based on small forcing amplitude..J. Binder, M.G. Blyth and S. Balasuriy

Studies on the fleece fibres of British breeds of sheep

In connection with a sheep hybridising experiment which is being carried cut by the Animal Breeding Research Department, a microscopical analysis of the fleece of the parental breeds involved (viz. Scuthdown and Blackface Mountain) was undertaken. It was hoped in this way to make a complete survey of all British breeds, describing in the first place those which are most frequently used for crossing on account of their greater value in the study of the inheritance of fleece characters. However, this study had not long been commenced, when it became evident that if the original method of examining each breed separately and thoroughly in sequence were adhered to, while useful data would be collected in large numbers, much of the significance of such infcrmat ion would only be exposed at the end of the investigation, or indeed some points would be entirely lost sigh of if they were not accentuated until some breed towards the middle of the series was reached. Moreover, the time required to carry cut the work on such a scale would stretch over many years.Accordingly, the position was reconsidered and it was decided that the quickest way to optimum results lay in first carrying out a breed survey on the smallest scale compatible with reasonable accuracy in general and basic results. Such a study would at least present a bird's eye view of the situation and would, in all probability, show or suggest more specific lines of research which might be followed with advantage.The work was carried out at the Animal Breeding Research Department, the University, Edinburgh, and my best thanks are due to Dr F. A. E. Crew, Director, for the facilities and opportunities afforded to me during the course of this investigation. I am very deeply indebted to Professor Barker, University of Leeds, for his kindness in supplying me with most of the wool necessary for this study.1. Two main types of fibres occur in British breeds of sheep. Type I is proportionally the longer and coarser and exhibits c iaracteristic scale markings. It appears to occur only in the Lustre and the Mountain Longwool groups of breeds. Type II ir shorter and finer and possesses a coronal type of scale marking; it occurs in all breed groups. It constitutes the main type in the Short Wools, is present in varying proportion in the Mountain Longwools and the Lustres. In some samples of the latter group, however, its component fibres are very few in number.2. Two small subsidiary classes of fibres are also found. Kemp, the coarsest type, is present in all breeds. It is shorter than the main types and is shed periodically, being usually found l ir.g loosely in the fleece with a complete tip &nc root. The other small group consists of very fine short fibres similar in structure to the finest members of type II. They were only identified in a few of the samples, but it is possible that they were present in all breeds but were not separable from type II.3. Type I and kemp are considered to be homologous with the hair of the primitive breeds of sheep, while the primitive wool is represented in modern breeds-by type II and the small group of fine fibres.4. Medulla. varies greatly even within individual breeds. It has a greater tendency to appear in the homologues of primitive hair than those of wool, and occurs more frequently in the Mountain than in the Non-mountain wools. It is suggested that this variability is not wholly due to hereditary influences but is in some measure caused by environment

Assessing preventable hospitalisation indicators (APHID): protocol for a data-linkage study using cohort study and administrative data

Introduction Potentially preventable hospitalisation (PPH) has been adopted widely by international health systems as an indicator of the accessibility and overall effectiveness of primary care. The Assessing Preventable Hospitalisation InDicators (APHID) study will validate PPH as a measure of health system performance in Australia and Scotland. APHID will be the first large-scale study internationally to explore longitudinal relationships between primary care and PPH using detailed person-level information about health risk factors, health status and health service use. Methods and analysis APHID will create a new longitudinal data resource by linking together data from a large-scale cohort study (the 45 and Up Study) and prospective administrative data relating to use of general practitioner (GP) services, dispensing of pharmaceuticals, emergency department presentations, hospital admissions and deaths. We will use these linked person-level data to explore relationships between frequency, volume, nature and costs of primary care services, hospital admissions for PPH diagnoses, and health outcomes, and factors that confound and mediate these relationships. Using multilevel modelling techniques, we will quantify the contributions of person-level, geographic-level and service-level factors to variation in PPH rates, including socioeconomic status, country of birth, geographic remoteness, physical and mental health status, availability of GP and other services, and hospital characteristics. Ethics and dissemination Participants have consented to use of their questionnaire data and to data linkage. Ethical approval has been obtained for the study. Dissemination mechanisms include engagement of policy stakeholders through a reference group and policy forum, and production of summary reports for policy audiences in parallel with the scientific papers from the study.</p

Calibrating the glycerol dialkyl glycerol tetraether temperature signal in speleothems

Palaeotemperature proxies based on glycerol dialkyl glycerol tetraethers (GDGTs) lipids have been established for marine and lacustrine environments, but there has been relatively little study of their application in speleothems. In this study we analyse the GDGT content of 33 speleothem samples from 16 different sites around the globe, and test whether proxies based on isoprenoid tetraethers (TEX86) or branched tetraethers (MBT/CBT) are correlated with measured surface and cave mean annual air temperature (MAT). The results show that the TEX86 has a strong relationship with measured temperature (r2 = 0.78, standard error of the estimate 2.3 C, when calibrated with surface MAT). Furthermore, the MBT/CBT also showed a significant relationship with temperature (r2 = 0.73, standard error of the estimate 2.7 C, when calibrated with surface MAT). Some issues remain requiring future work, in particular the development of a larger calibration sample set with measured cave temperature data, and the investigation of controls other than temperature on GDGT distribution, but overall the results indicate that GDGT based proxies derived from speleothems may be highly viable new methods for reconstructing continental palaeotemperatures

Quantified HI Morphology VII: star-formation and tidal influence on local dwarf HI morphology

Scale-invariant morphology parameters applied to atomic hydrogen maps (HI) of galaxies can be used to quantify the effects of tidal interaction or star-formation on the ISM. Here we apply these parameters, Concentration, Asymmetry, Smoothness, Gini, M20, and the GM parameter, to two public surveys of nearby dwarf galaxies, the VLA-ANGST and LITTLE-THINGS survey, to explore whether tidal interaction or the ongoing or past star-formation is a dominant force shaping the HI disk of these dwarfs. Previously, HI morphological criteria were identified for ongoing spiral-spiral interactions. When we apply these to the Irregular dwarf population, they either select almost all or none of the population. We find that only the Asymmetry-based criteria can be used to identify very isolated dwarfs (i.e., these have a low tidal indication). Otherwise, there is little or no relation between the level of tidal interaction and the HI morphology. We compare the HI morphology to three star-formation rates based on either Halpha, FUV or the resolved stellar population, probing different star-formation time-scales. The HI morphology parameters that trace the inequality of the distribution, the Gini, GM, and M20 parameters, correlate weakly with all these star-formation rates. This is in line with the picture that local physics dominates the ISM appearance and not tidal effects. Finally, we compare the SDSS measures of star-formation and stellar mass to the HI morphological parameters for all four HI surveys. In the two lower-resolution HI surveys (12"), there is no relation between star-formation measures and HI morphology. The morphology of the two high-resolution HI surveys (6"), the Asymmetry, Smoothness, Gini, M20, and GM, do show a link to the total star-formation, but a weak one.Comment: 26 figures, 4 tables, two appendices. Third appendix (HI maps of all galaxies) omitted. Accepted by MNRA

Event by Event fluctuation in K/pi ratio at RHIC

We present the preliminary results from our analysis of event by event fluctuation in K/pi ratio in Au+Au collision at \sqrt s_{NN} = 200 GeV and at 62.4 GeV using STAR detector at RHIC. Two different methods have been used to extract the strength of dynamical fluctuation and the centrality dependence of that. The results from the study of energy and centrality dependence of the dynamical fluctuation are presented. From the excitation function it is seen that at two RHIC energies the measure of dynamical fluctuation is constant with values very close to that at 12.3 GeV at SPS. The dynamical fluctuation is found to be positive and decreasing with increasing centrality at RHIC. The results are compared with HIJING model calculation with jets. Results from HIJING are found to be very close to data from central collisions whereas it over predicts the data for peripheral events.Comment: 4 pages, 3 figures, for ICPAQGP - 2005 (Recalculated the errors shown in Fig 2 and Table 1