Galaxy size trends as a consequence of cosmology

We show that recently documented trends in galaxy sizes with mass and redshift can be understood in terms of the influence of underlying cosmic evolution; a holistic view which is complimentary to interpretations involving the accumulation of discreet evolutionary processes acting on individual objects. Using standard cosmology theory, supported with results from the Millennium simulations, we derive expected size trends for collapsed cosmic structures, emphasising the important distinction between these trends and the assembly paths of individual regions. We then argue that the observed variation in the stellar mass content of these structures can be understood to first order in terms of natural limitations of cooling and feedback. But whilst these relative masses vary by orders of magnitude, galaxy and host radii have been found to correlate linearly. We explain how these two aspects will lead to galaxy sizes that closely follow observed trends and their evolution, comparing directly with the COSMOS and SDSS surveys. Thus we conclude that the observed minimum radius for galaxies, the evolving trend in size as a function of mass for intermediate systems, and the observed increase in the sizes of massive galaxies, may all be considered an emergent consequence of the cosmic expansion.Comment: 14 pages, 13 figures. Accepted by MNRA

Constraints and subsequent limitations to parental involvement in primary schools in Abu Dhabi: stakeholders' perspective

The United Arab Emirates (UAE) is developing its public schools by initiating reform agendas for school improvement. High on the list of reforms is the call to increase parental involvement in schools. For this reform to work successfully, it is important to identify and examine the constraints and subsequent limitations that exist. Seven primary Public, Private Partnership schools (PPP) in Abu Dhabi were the focus of this qualitative case study. Participants were school stakeholders: school administrators, social workers, teachers and parents. The findings will assist in developing continuing policies and practices which take these limitations into account and work to mitigate them. Recommendations are made based within the context of the findings

Pharmacogenomics in drug development : implementation and application of PKPD model based approaches

Model based approaches, integrating physiological parameters or linking exposure with response, are powerful tools to quantify and evaluate the impact of genetic differences that are reflected as variability of drug exposure and/or clinical response(s). This thesis __Pharmacogenomics in Drug Development: Implementation and Application of PKPD Model Based Approaches__ focused on genotype differences in explaining inter-individual variability in drug metabolism and clinical response. Population pharmacokinetic and pharmacodynamic models were developed to evaluate the relationship between exposure differences resulting from UGT2B15 genotype and their effects on both fasting plasma glucose and glycosylated haemoglobin for the type 2 diabetes drug, Sipoglitazar__. The model was used to quantify the optimal dose and regime (Single treatment/genotyped-based or titrated based upon response) for future clinical trials. Evaluating the potential impact of genetic differences early during development is important to appropriately design future clinical studies and to ensure that exposure response relationships for efficacy and safety can be identifed for all genetic subgroups. Ultimately, these model-based approaches can be used to determine if covariate-based dose individualization would be advantageous/beneficial to normalize exposure and minimize variability in clinical outcomes across heterogeneous clinical populations.Takeda Pharmaceutical CompanyUBL - phd migration 201

Analytic and numerical realisations of a disk galaxy

Recent focus on the importance of cold, unshocked gas accretion in galaxy formation -- not explicitly included in semi-analytic studies -- motivates the following detailed comparison between two inherently different modelling techniques: direct hydrodynamical simulation and semi-analytic modelling. By analysing the physical assumptions built into the Gasoline simulation, formulae for the emergent behaviour are derived which allow immediate and accurate translation of these assumptions to the Galform semi-analytic model. The simulated halo merger history is then extracted and evolved using these equivalent equations, predicting a strikingly similar galactic system. This exercise demonstrates that it is the initial conditions and physical assumptions which are responsible for the predicted evolution, not the choice of modelling technique. On this level playing field, a previously published Galform model is applied (including additional physics such as chemical enrichment and feedback from active galactic nuclei) which leads to starkly different predictions.Comment: 15 pages, 15 figure

Design Guidance on Low Impact Development Practices for Stormwater Management and Control in Oklahoma

Since the National Pollutant Discharge Elimination System regulations were first implemented in Oklahoma in 1990 stormwater management has evolved in many ways. One of these evolutions has came by the way of the EPA encouraging communities to utilize Low Impact Development (LID) to deal with both stormwater quantity and achieve water quality benefits. In the last 5 years the installation of LID practices in the United States have grown tremendously. The purpose of this Thesis is to research the existing technology and implementation surrounding LID and document the findings to educate a variety of groups such as engineers, homebuilders, developers, homeowners, and scientists. Objectives of the research include indentifying LID practices appropriate for Oklahoma, developing comprehensive fact sheets on each practice for use in a future LID Manual, and identifying examples of LID practices currently in place in Oklahoma. Each chapter includes information on benefits, design, installation, cost, maintenance, and limitations of the following practices: rain gardens and bioretention cells, rainwater harvesting, pervious pavement, natural and engineered wetlands, and green roofs. Other chapters included are a comparison of traditional development to LID and pollutant source reduction. This series of fact sheets will provide a resource for the citizens of Oklahoma to utilize to determine if LID practices could be valuable to implement.Environmental Sciences Progra

How do atmospheric rivers form?

Identifying the source of atmospheric rivers: Are they rivers of moisture exported from the subtropics or footprints left behind by poleward travelling storms? The term atmospheric river is used to describe corridors of strong water vapor transport in the troposphere. Filaments of enhanced water vapor, commonly observed in satellite imagery extending from the subtropics to the extratropics, are routinely used as a proxy for identifying these regions of strong water vapor transport. The precipitation associated with these filaments of enhanced water vapor can lead to high impact flooding events. However, there remains some debate as to how these filaments form. In this paper we analyse the transport of water vapor within a climatology of wintertime North Atlantic extratropical cyclones. Results show that atmospheric rivers are formed by the cold front which sweeps up water vapor in the warm sector as it catches up with the warm front. This causes a narrow band of high water vapor content to form ahead of the cold front at the base of the warm conveyor belt airflow. Thus, water vapor in the cyclone's warm sector, and not long-distance transport of water vapor from the subtropics, is responsible for the generation of filaments of high water vapor content. A continuous cycle of evaporation and moisture convergence within the cyclone replenishes water vapor lost via precipitation. Thus, rather than representing a direct and continuous feed of moist air from the subtropics into the centre of a cyclone (as suggested by the term atmospheric river), these filaments are, in-fact, the result of water vapor exported from the cyclone and thus they represent the footprints left behind as cyclones travel polewards from subtropics

A reverse engineering approach to the suppression of citation biases reveals universal properties of citation distributions

The large amount of information contained in bibliographic databases has recently boosted the use of citations, and other indicators based on citation numbers, as tools for the quantitative assessment of scientific research. Citations counts are often interpreted as proxies for the scientific influence of papers, journals, scholars, and institutions. However, a rigorous and scientifically grounded methodology for a correct use of citation counts is still missing. In particular, cross-disciplinary comparisons in terms of raw citation counts systematically favors scientific disciplines with higher citation and publication rates. Here we perform an exhaustive study of the citation patterns of millions of papers, and derive a simple transformation of citation counts able to suppress the disproportionate citation counts among scientific domains. We find that the transformation is well described by a power-law function, and that the parameter values of the transformation are typical features of each scientific discipline. Universal properties of citation patterns descend therefore from the fact that citation distributions for papers in a specific field are all part of the same family of univariate distributions.Comment: 9 pages, 6 figures. Supporting information files available at http://filrad.homelinux.or