On NCQFT and dimensionless insertions

In these notes, we aim at a precise definition of the tree level action for the noncommutative scalar and gauge field theories on four-dimensional canonically deformed Euclidean space. As tools to achieve this goal we employ power counting and normalization conditions.Comment: 10 page

On Non-Commutative U*(1) Gauge Models and Renormalizability

Based on our recent findings regarding (non-)renormalizability of non-commutative U*(1) gauge theories [arxiv:0908.0467, arxiv:0908.1743] we present the construction of a new type of model. By introducing a soft breaking term in such a way that only the bilinear part of the action is modified, no interaction between the gauge sector and auxiliary fields occurs. Demanding in addition that the latter form BRST doublet structures, this leads to a minimally altered non-commutative U*(1) gauge model featuring an IR damping behavior. Moreover, the new breaking term is shown to provide the necessary structure in order to absorb the inevitable quadratic IR divergences appearing at one-loop level in theories of this kind. In the present paper we compute Feynman rules, symmetries and results for the vacuum polarization together with the one-loop renormalization of the gauge boson propagator and the three-point functions.Comment: 20 pages, 4 figures; v2-v4: clarified several points, and minor correction

Gauge Theories on Deformed Spaces

The aim of this review is to present an overview over available models and approaches to non-commutative gauge theory. Our main focus thereby is on gauge models formulated on flat Groenewold-Moyal spaces and renormalizability, but we will also review other deformations and try to point out common features. This review will by no means be complete and cover all approaches, it rather reflects a highly biased selection.Comment: v2 references added; v3 published versio

Design principles for digital value co-creation networks—a service-dominant logic perspective

Information systems (IS) increasingly expand actor-to-actor networks beyond their temporal, organizational, and spatial boundaries. In such networks and through digital technology, IS enable distributed economic and social actors to not only exchange but also integrate their resources in materializing value co-creation processes. To account for such IS-enabled value co-creation processes in multi-actor settings, this research gives rise to the phenomenon of digital value co-creation networks (DVNs). In designing DVNs, it is not only necessary to consider underpinning value co-creation processes, but also the characteristics of the business environments in which DVNs evolve. To this end, our study guides the design of DVNs through employing service-dominant logic, a theoretical lens that conceptualizes value co-creation as well as business environments. Through an iterative research process, this study derives design requirements and design principles for DVNs, and eventually discusses how these design principles can be illustrated by expository design features for DVNs

A Value Co-creation Perspective on Information Systems Analysis and Design

Information systems analysis and design (ISAD) ensures the design of information systems (IS) in line with the requirements of a business environment. Since ISAD approaches follow the currently dominant logic of busi- ness, the rise of a new and thriving business logic may require revisiting and advancing extant ISAD approaches and techniques. One of the prevailing debates in marketing research is the paradigmatic shift from a goods-dominant (G-D) to a service-dominant (S-D) logic of business. The cornerstone of this reorientation is the concept of value co- creation emphasizing joint value creation among a variety of actors within a business network. With the aim of introducing value co-creation as a new discourse to ISAD research, this research note argues that (1) the lens of S-D logic with its core concept of value co-creation provides a novel perspective to ISAD. The authors also assert that (2) value co-creation-informed IS design realizes the paradig- matic shift from G-D to S-D logic. Building on this mutual relationship between value co-creation and ISAD, they propose a research agenda and discuss the ISAD artifacts that prospective research may target

Taxonomy of Digital Platforms: A Platform Architecture Perspective

Digital platforms—technical core artefacts augmented by peripheral third-party derivatives—afford organizations to integrate resources in networked business ecosystems. Although digital platforms widely differ in their configurations, digital platforms’ dimensions and characteristics to disentangle different digital platform configurations are under-researched. To bridge this void, we employ Nickerson et al.’s method for taxonomy development to systematically derive a taxonomy of digital platforms. Specifically, we embrace a platform architecture perspective to capture the configuration of digital platform’s components. The resultant taxonomy facilitates a more pronounced understanding and grouping of digital platforms as configurations of certain dimensions and characteristics. Our findings suggest that digital platforms exhibit characteristics on at least four dimensions—namely, infrastructure, core, ecosystem, and service dimensions. Second, through instantiating the taxonomy, we find that digital platforms that exhibit similar characteristics share identical architectural profiles and, therefore, belong to one of three digital platform archetypes—namely, orchestration, amalgamation, and innovation platforms

Vegetation and Landscape Dynamics in Eastern Taranaki Hill Country

An ecological study of hill country landscapes in eastern Taranaki, New Zealand, was undertaken as part of a project concerning the implications of long-term soil mantle changes for sustainable land use. The study was undertaken in a 417 km2 area comprising uplifted and steeply dissected soft Tertiary sediments with a predominantly sandstone lithology. Rapid European settlement in the 1890s modified the natural vegetation cover greatly, so that most remaining forest in the study area occurs in patches surrounded by a matrix of pastoral land. Vegetational and successional patterns and environmental variation : The pattern of woody vegetation was investigated by extensive reconnaissance sampling incorporating semi-quantitative analysis of canopy cover, followed by intensive, environmentally stratified sampling. The vegetation was classified on a structural and floristic basis into 19 units of forest, treeland, scrub and shrubland. The effect of environmental variation on vegetation composition was investigated by reciprocal averaging ordination (DECORANA). The first ordination axis was correlated to vegetation structure and canopy height and was interpreted as a complex disturbance gradient relating to time since disturbance. The second and third axes were related to soil fertility and topographical gradients. Forest plots were dominated by Beilschmiedia tawa and Weinmannia racemosa and had basal area values of up to >250 m2/ha. Basal area, stem and seedling density varied greatly between vegetation structural groups. Regeneration of woody vegetation following various types of disturbance: The disturbance regime was comprehensively documented. Main factors of natural disturbance are landslide erosion and windthrow; main factors of cultural disturbance are direct clearance by felling and burning, and introduced animals. A chronology is presented of successional pathways for about 400 years following major disturbance. Succession proceeds through shrubland and scrub stages dominated by treeferns, Leptospermwn scoparium or other broadleaved woody shrubs, through treeland, to broadleaved forest dominated firstly by W. racemosa or Knightia excelsa, then by B. tawa. Podocarp trees are generally only prominent after a long period of uninterrupted succession. Seedling recruitment, mortality and growth were monitored for 2 years. Seedling dynamics varied considerably between and within sampling plots, some of which contained small exclosures that excluded possums and goats. The effects of introduced animals on seedling recruitment and vegetation growth is strongly modified by microtopography. Most dominant species showed continuous regeneration at the scale of the whole study area, despite local discontinuities. This pattern was consistent with a model of interrpted gap-phase regeneration, which may be widely applicable to New Zealand lowland forests. The vegetation turnover time is in the order of 150-250 years, a period consistent with comparable temperate forest ecosystems. The successional pathway is primarily dependent on topography, previous site history and location and area of disturbance. The existence of residual-soils on landslide scars, variations in plant propagule supply, and rapid loss of soil from steep slopes cleared for agriculture, all suggest that a rigid distinction between primary and secondary succession in the study area is not appropriate. Hillslope processes underlying vegetation and landscape change: Hillslope processes were studied in five 0.1 ha plots in which slope profiles were measured, vegetation and microtopography mapped in detail, vegetation age assessed and soil properties investigated. Ground surface age was assessed as an interpretation of the above data. Mean surface age was c. 450 years, but some swales had a surface age of several thousand years. There was a significant correlation between surface age and soil depth, soil depth increase being faster and continuing for much longer under forest than under pasture. Observations were made of near-surface erosion processes such as soil creep. A model of hillslope erosion is outlined, involving periodic evacuation of swales by landslides and refilling of swales by near-surface erosion. Evidence of past environments supports a fluvial origin for swales in an early Ohakean (glacial maximum) or pre-Ohakean period of high erosion. A concluding synthesis of vegetation, topography and soils emphasises the importance of selecting appropriate temporal and spatial scales at which to study landscape processes

Complete Genome Sequencing of Acinetobacter sp. Strain LoGeW2-3, Isolated from the Pellet of a White Stork, Reveals a Novel Class D Beta-Lactamase Gene

Whole-genome sequencing of Acinetobacter sp. strain LoGeW2-3, isolated from the pellet of a white stork (Ciconia ciconia), reveals the presence of a plasmid of 179,399 bp encoding a CRISPR-Cas (clustered regularly interspaced short palindromic repeats and associated genes) system of the I-F type, and the chromosomally encoded novel class D beta-lactamase OXA-568

Translation-invariant models for non-commutative gauge fields

Motivated by the recent construction of a translation-invariant renormalizable non-commutative model for a scalar field (see arXiv:0802.0791 [math-ph]), we introduce models for non-commutative U(1) gauge fields along the same lines. More precisely, we include some extra terms into the action with the aim of getting rid of the UV/IR mixing.Comment: 9 page