Enhanced non-perturbative effects through the collinear anomaly

We show that non-perturbative effects are logarithmically enhanced for transverse-momentum-dependent observables such as q_T-spectra of electroweak bosons in hadronic collisions and jet broadening at e^+e^- colliders. This enhancement arises from the collinear anomaly, a mechanism characteristic for transverse observables, which induces logarithmic dependence on the hard scale in the product of the soft and collinear matrix elements. Our analysis is based on an operator product expansion and provides, for the first time, a systematic, model-independent way to study non-perturbative effects for this class of observables. For the case of jet broadening, we relate the leading correction to the non-perturbative shift of the thrust distribution.Comment: 5 pages, 2 figures. v2: Minor changes, references added. Journal versio

Microbes in the Anthropocene: spillover of agriculturally selected bacteria and their impact on natural ecosystems

Soil microbial communities are enormously diverse, with at least millions of species and trillions of genes unknown to science or poorly described. Soil microbial communities are key components of agriculture, for example in provisioning nitrogen and protecting crops from pathogens, providing overall ecosystem services in excess of $1000bn per year. It is important to know how humans are affecting this hidden diversity. Much is known about the negative consequences of agricultural intensification on higher-organisms, but almost nothing is known about how alterations to landscapes affect microbial diversity, distributions and processes. We review what is known about spatial flows of microbes and their response to land use change, and outline nine hypotheses to adva nce research of microbiomes across landscapes. We hypothesise that intensified agriculture selects for certain taxa and genes, which then “spill over” into adjacent unmodified areas and generate a halo of genetic differentiation around agricultural fields. Consequently, the spatial configuration and management intensity of different habitats combines with the dispersal ability of individual taxa to determine the extent of spillover, which can impact the functioning of adjacent unmodified habitats. When land scapes are heterogeneous and dispersal rates are high, this will select for large genomes that allow exploitation of multiple habitats , a process that may be accelerated through horizontal gene transfer. Continued expansion of agriculture will increase genotypic similarity, making microbial community functioning increasingly variable in human - dominated landscapes , potentially also impacting the consistent provisioning of ecosystem services . While the resulting economic costs have not been calculated, it is clear that dispersal dynamics of microbes should be taken into consideration to ensure that ecosystem functioning and services are maintained in agri - ecosystem mosaics

Computer performance analysis - Measurement objectives and tools

Objectives and measurements in computer performance analysi

The Health Related Components of Physical Fitness in People with Visual Impairment: A Systematic Review

Visual impairment is becoming progressively more common in America’s aging society. Physical inactivity contributes to the development of chronic health conditions. Therefore, it is important to understand the relationship between visual impairment and its impact on health related physical activity and fitness. The purpose of this systematic review is to examine the prevalence of physical activity and the five components of physical fitness in the visually impaired population. This review was limited to articles addressing individuals with “visual impairment,” as defined by the National Eye Institute. The data abstracted included documentation of visual impairment, physical activity rates, physical fitness measures, gender, age, number of participants, and sample size. Results confirm that persons with visual impairment tend to participate in physical activity significantly less than their sighted counterparts and are often less physically fit, especially in regards to body composition, cardiovascular endurance, and muscular strength. Consensus within the research attributes this decreased physical fitness to the lack of sufficient physical activity within the population. The observed lack of physical activity warrants intentionally improving upon the many physiopsychological and social factors which prevent visually impaired children and adults from having equal access to opportunities to engage regularly in physical fitness activities

The "Carex" fen vegetation of northern New South Wales

The floristic composition and extent of Carex-dominated fens in the New South Wales New England Tablelands Bioregion and Barrington Tops area (lat 28° 41’ S–31° 55’ S; long 151° 23’ E–152° 05’ E) together with outliers from the central west (Coonabarabran) are described from 81 full floristic survey sites. These fens contained 234 vascular plant taxa of which 27% were exotic. The fens were dominated by herbaceous vegetation (96% of taxa). Cluster analysis of cover-abundance scores of vascular plant taxa from 81 plots placed within 71 separate Carex fens revealed three alliances: 1) Carex appressa, 2) Scirpus polystachyus – Carex tereticaulis and 3) Carex gaudichaudiana and seven communities: (1) Carex appressa – Stellaria angustifolia Fen (2) Carex appressa Fen (3) Scirpus polystachyus – Carex appressa Fen (4) Carex tereticaulis Fen (5) Carex gaudichaudiana – Isachne globosa Fen (6) Carex sp. Bendemeer – Carex gaudichaudiana Fen (7) Carex gaudichaudiana – Glyceria australis Fen The distribution of alliances showed a pattern of east-west separation. The most easterly alliance shares many features with the Carex gaudichaudiana Alliance of the Monaro Region of southern NSW while the other alliances have no counterparts within the current literature. We estimate that up to 5 000 ha of fen vegetation survive in the New England Bioregion of which 90% is on grazed land and only 0.2% is within conservation reserves. Seven outstanding examples of fens remain; most are examples of Community 5, with one representing Community 6 and none representing the other five communities. Many of these are not secured, and none of those within reserves are in their ‘natural’ state. We therefore strongly encourage measures to allow closure of drains, the opening of dams, and the rehabilitation of important fens such as Bishops, Racecourse and New Country Swamps

Vegetation of montane bogs in east-flowing catchments of northern New England, New South Wales

The floristics of the montane bogs in east-flowing catchments of northern New England, north-eastern New South Wales (lat 28° 47’–31° 25’ S; long 151° 50’–152° 30’ E), are described from 62 full floristic survey sites (20 x 20 m in area). Eight vegetation communities are based on flexible UPGMA analysis of cover-abundance scores of vascular plant taxa. Shrub species make up 26% of the flora and herb species 69%, with the remaining taxa trees, climbers or vines. Shrub species were of little diagnostic value, as a few common dominants were shared across most communities. The herbaceous layer was found to be of better circumscriptive value. Communities described (based on dominant herbaceous species) are: (1) Themeda australis – Gonocarpus micranthus, (2) Baumea articulata – Baloskion stenocoleum, (3) Lepidosperma limicola – Baloskion stenocoleum, (4) Baloskion fimbriatum – Lomandra longifolia, (5) Lepyrodia scariosa – Blandfordia grandiflora, (6) Lepidosperma gunnii – Lepidosperma scariosa, (7) Baloskion stenocoleum – Empodisma minus, (8) Lepidosperma limicola – Xyris operculata. The mean annual moisture index was found to account for 26% of the variation in species density. These montane bog systems are some of the richest in Australia, with a high number of rare and restricted taxa. They are vulnerable to both present landuse practices and future changes in climate, are restricted in area, and need further conservation efforts to ensure their long-term survival

Search for acoustic signals from high energy cascades

High energy cosmic ray secondaries can be detected by means of the cascades they produce when they pass through matter. When the charged particles of these cascades ionize the matter they are traveling through, the heat produced and resulting thermal expansion causes a thermoacoustic wave. These sound waves travel at about one hundred-thousandth the speed of light, and should allow an array of acoustic transducers to resolve structure in the cascade to about 1 cm without high speed electronics or segmentation of the detector

Anomalies, Chern-Simons Terms and Chiral Delocalization in Extra Dimensions

Gauge invariant topological interactions, such as the D=5 Chern-Simons terms, are required in models in extra dimensions that split anomaly free representations. The Chern-Simons term is necessary to maintain the overall anomaly cancellations of the theory, but it can have significant, observable, physical effects. The CS-term locks the KK-mode parity to the parity of space-time, leaving a single parity symmetry. It leads to new processes amongst KK-modes, eg, the decay of a KK-mode to a 2-body final state of KK-modes. A formalism for the effective interaction amongst KK-modes is constructed, and the decay of a KK-mode to KK-mode plus zero mode is analyzed as an example. We elaborate the general KK-mode current and anomaly structure of these theories. This includes a detailed study of the triangle diagrams and the associated ``consistent anomalies'' for Weyl spinors on the boundary branes. We also develop the non-abelian formalism. We illustrate this by showing in a simple way how a D=5 Yang-Mills ``quark flavor'' symmetry leads to the D=4 chiral lagrangian of mesons and the quantized Wess-Zumino-Witten term.Comment: 51 pages, 3 figures; Corrected typos, amplified discussio