Review of Genesis of a Music (2nd edition) by Harry Partch

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Geometric Modular Action and Spacetime Symmetry Groups

A condition of geometric modular action is proposed as a selection principle for physically interesting states on general space-times. This condition is naturally associated with transformation groups of partially ordered sets and provides these groups with projective representations. Under suitable additional conditions, these groups induce groups of point transformations on these space-times, which may be interpreted as symmetry groups. The consequences of this condition are studied in detail in application to two concrete space-times -- four-dimensional Minkowski and three-dimensional de Sitter spaces -- for which it is shown how this condition characterizes the states invariant under the respective isometry group. An intriguing new algebraic characterization of vacuum states is given. In addition, the logical relations between the condition proposed in this paper and the condition of modular covariance, widely used in the literature, are completely illuminated.Comment: 83 pages, AMS-TEX (format changed to US letter size

New developments in the theory of Groebner bases and applications to formal verification

We present foundational work on standard bases over rings and on Boolean Groebner bases in the framework of Boolean functions. The research was motivated by our collaboration with electrical engineers and computer scientists on problems arising from formal verification of digital circuits. In fact, algebraic modelling of formal verification problems is developed on the word-level as well as on the bit-level. The word-level model leads to Groebner basis in the polynomial ring over Z/2n while the bit-level model leads to Boolean Groebner bases. In addition to the theoretical foundations of both approaches, the algorithms have been implemented. Using these implementations we show that special data structures and the exploitation of symmetries make Groebner bases competitive to state-of-the-art tools from formal verification but having the advantage of being systematic and more flexible.Comment: 44 pages, 8 figures, submitted to the Special Issue of the Journal of Pure and Applied Algebr

Tacit and Explicit Knowledge in Software Development Projects: A Combined Model for Analysis

The development of new or updated software packages by software companies often involves the specification of new features and functionality required by customers, who may already be using a version of the software package. The on-going development and upgrade of such packages is the norm, and the effective management of knowledge in this process is critical to achieving successful enhancement of the package in line with customer expectations. Human interaction within the software development process becomes a key focus, and knowledge transfer an essential mechanism for delivering software to quality standards and within agreed timescales and budgetary constraints. This article focuses on the role and nature of knowledge within the context of software development, and puts forward a combined conceptual model to aid in the understanding of individual and group tacit knowledge in this business and operational environment

Investigation of Quark-Antiquark Interaction Properties using Leading Particle Measurements in e+e- Annihilation

Measurements of heavy quark production in electron-positron collisions are used to analyse the strong interactions between quarks and anti-quarks. A scaling behaviour is observed in distributions of the rapidity change of D*, B*, and B mesons. From these distributions information is obtained on the hadron formation time, effective quark masses, and the potential between quark-antiquark pairs. Predictions for fragmentation functions are presented.Comment: 10 pages, 4 figures, fig.2 references added, revised version accepted by Physics Letters

Health related quality of life in patients with end stage kidney disease treated with haemodialysis in Malawi: a cross sectional study

Kidney Disease and Quality of Life Short Form Questionnaire (KDQOL-SFTM). (PDF 168 kb

Tacit and Explicit Knowledge in Software Development Projects: Towards a Conceptual Framework for Analysis

The management and delivery of software development projects remains a key business activity in many industries. Although the advent of packaged software products has reduced the incidence of in-house development, bespoke software is still important for some industrial sectors - notably in the finance, defence and security industries. Despite the recognized criticality of software project success for organizations, a considerable proportion of projects continue to either not meet their due dates, exceed budget, do not deliver to specification, miss quality targets, or do not meet customer requirements. Software project failure – be it bespoke products or the implementation of commercially available packages - remains an area of considerable interest in contemporary software project management literature, and the management and transfer of knowledge within both these types of project is a key dimension and driver of project outcomes. This paper examines how knowledge definition and management can be applied within a conceptual framework to improve software development project outcomes

Experimental harvesting of fish populations drives genetically based shifts in body size and maturation

Size-selective harvesting in commercial fisheries can induce rapid changes in biological traits. While experimental and wild harvested populations often exhibit clear shifts in body size and maturation associated with fishing pressure, the relative contributions of genetic and environmental factors to these shifts remain uncertain and have been much debated. To date, observations of so-called fisheries-induced evolution (FIE) have been based solely on phenotypic measures, such as size data. Genetic data are hitherto lacking. Here, we quantify genetic versus environmental change in response to size-selective harvesting for small and large body size in guppies (Poecilia reticulata) across three generations of selection. We document for the first time significant changes at individual genetic loci, some of which have previously been associated with body size. In contrast, variation at neutral microsatellite markers was unaffected by selection, providing direct genetic evidence for rapid evolution induced by size-selective harvesting. These findings demonstrate FIE in an experimental system, with major implications for the sustainability of harvested populations, as well as impacts on size-structured communities and ecosystem processes. These findings highlight the need for scientists and managers to reconsider the capacity of harvested stocks to adapt to, and recover from, harvesting and predation. © 2013 The Ecological Society of America

The GALEX Arecibo SDSS Survey. VI. Second Data Release and Updated Gas Fraction Scaling Relations

We present the second data release from the GALEX Arecibo SDSS Survey (GASS), an ongoing large Arecibo program to measure the HI properties for an unbiased sample of ~1000 galaxies with stellar masses greater than 10^10 Msun and redshifts 0.025<z<0.05. GASS targets are selected from the Sloan Digital Sky Survey (SDSS) spectroscopic and Galaxy Evolution Explorer (GALEX) imaging surveys, and are observed until detected or until a gas mass fraction limit of a few per cent is reached. This second data installment includes new Arecibo observations of 240 galaxies, and marks the 50% of the complete survey. We present catalogs of the HI, optical and ultraviolet parameters for these galaxies, and their HI-line profiles. Having more than doubled the size of the sample since the first data release, we also revisit the main scaling relations of the HI mass fraction with galaxy stellar mass, stellar mass surface density, concentration index, and NUV-r color, as well as the gas fraction plane introduced in our earlier work.Comment: 30 pages, 12 figures. Accepted for publication in A&A. Version with complete Appendix A available at http://www.mpa-garching.mpg.de/GASS/pubs.php . GASS released data can be found at http://www.mpa-garching.mpg.de/GASS/data.ph