Kinematics of the Outer Stellar Halo

We have tested whether the simple model for the kinematics of the Galactic stellar halo (in particular the outer halo) proposed by Sommer-Larsen, Flynn and Christensen (SLFC) is physically realizable, by directly integrating particles in a 3-D model of the Galactic potential. We are able to show that the SLFC solution can be realized in terms of a distribution of particles with stationary statistical properties in phase-space. Hence, the SLFC model, which shows a notable change in the anisotropy from markedly radial at the sun to markedly tangential beyond about Galactocentric radius r=20 kpc, seems a tenable description of outer halo kinematics.Comment: 13 pages, 6 figures, accepted for publication in MNRAS. also available at http://astro.utu.fi/~cflynn/papers/fslc4/fslc4.htm

Modelling Transport in an Interregional General Equilibrium Model with Externalities

In this working paper the regional impacts of road pricing on cars are analysed taking into account externality effects from transportation on wages and productivity. In the paper the direct impacts from changes in transport costs on level of wages and productivity (=direct externality effects) have been estimated. The direct and derived impacts of road pricing have been analysed with AKF’s local economic model LINE and include the impacts on regional production, income and employment. LINE is an interregional general equilibrium model, which uses an interregional social accounting matrix (SAM-K) and a regional transport satellite account as the basis for modelling. Additionally, data from a GIS-system (Technical University of Copenhagen) on transport costs have been included to estimate the demand for transport commodities and increase in transport demand and costs due to road pricing. The direct effects on level of wages and productivity have been included into the model together with all the direct effects on commodity prices from road pricing. In the working paper the total impacts of road pricing have been subdivided into 2 components: 1) The wage effects of reducing income net of commuting of increasing transport cost by introduction of road pricing, 2) the labour contraction effect from increasing wages through increase in commuting cost and 3) the negative productivity effects of introducing road pricing. In total the impacts of road pricing are substantial. Regions with high level of average commuting cost (suburban areas in Greater Copenhagen) suffers most, whereas the centre of Copenhagen suffers least because of short commuting distances. In rural areas impacts are on or just below average because low level of road pricing.

Exploratory modeling: Extracting causality from complexity

On 22 May 2011 a massive tornado tore through Joplin, Mo., killing 158 people. With winds blowing faster than 200 miles per hour, the tornado was the most deadly in the United States since modern record keeping began in the 1950s. ©2014. American Geophysical Union. All Rights Reserved

No nearby counterparts to the moving objects in the Hubble Deep Field

Ibata et al (1999) have recently discovered faint, moving objects in the Hubble Deep Field. The quantity, magnitudes and proper motions of these objects are consistent with old white dwarfs making up the Galactic dark halo. We review a number of ground-based proper motion surveys in which nearby dark halo white dwarfs might be present, if they have the colours and absolute magnitudes proposed. No such objects have been found, whereas we argue here that several times more would be expected than in the Hubble Deep Field. We conclude it is unlikely that hydrogen atmosphere white dwarfs make up a significant fraction of the halo dark matter. No limits can be placed yet on helium atmosphere dwarfs from optical searches.Comment: 7 pages, 4 figures, MNRAS LaTeX forma

A case of long thoracic nerve palsy

A 31 year old male developed unilateral neck pain associated with increased kyphotic posture 24 hours after having general anaesthesia for ankle surgery. The pain and postural adaptation resolved, but a painless shoulder dysfunction developed. Following assessment a provisional diagnosis of long thoracic nerve palsy was made, and a 'wait and see' approach to management was taken. The dysfunction gradually resolved over a 12 month period without further investigation or intervention. The case study is discussed in light of possible neurophysiological mechanisms involved and of published literature on the management of long thoracic nerve palsy

Quality appraisal as a part of the systematic review: a review of current methods

Systematic reviews frequently underpin national and international practice guidelines. Different approaches to the systematic review process, in particular quality appraisal, have been advocated. This paper discusses these approaches and highlights possible limitations which might impact upon the validity of the conclusions drawn. Practical alternatives are offered upon which systematic reviews may be appraised and conducted

Modelling Transport in an Interregional General Equilibrium Model with Externalities

In this working paper the regional impacts of road pricing on cars are analysed taking into account externality effects from transportation on wages and productivity. In the paper the direct impacts from changes in transport costs on level of wages and productivity (=direct externality effects) have been estimated. The direct and derived impacts of road pricing have been analysed with AKF's local economic model LINE and include the impacts on regional production, income and employment. LINE is an interregional general equilibrium model, which uses an interregional social accounting matrix (SAM-K) and a regional transport satellite account as the basis for modelling. Additionally, data from a GIS-system (Technical University of Copenhagen) on transport costs have been included to estimate the demand for transport commodities and increase in transport demand and costs due to road pricing. The direct effects on level of wages and productivity have been included into the model together with all the direct effects on commodity prices from road pricing. In the working paper the total impacts of road pricing have been subdivided into 2 components: 1) The wage effects of reducing income net of commuting of increasing transport cost by introduction of road pricing, 2) the labour contraction effect from increasing wages through increase in commuting cost and 3) the negative productivity effects of introducing road pricing. In total the impacts of road pricing are substantial. Regions with high level of average commuting cost (suburban areas in Greater Copenhagen) suffers most, whereas the centre of Copenhagen suffers least because of short commuting distances. In rural areas impacts are on or just below average because low level of road pricing

Non-prescription sun eyewear optical performance study

Non-prescription sun eyewear often has induced refractive power, prismatic deviations and variability in resolution within their lenses. The goal of current sun eyewear manufactures is to provide maximum optical quality in their lenses. In order to achieve superior optical quality in their lenses, manufactures attempt to have low refractive power, low prismatic power, and high resolution within and between their lenses. The purpose of this study was to assess various optical qualities including refractive power, prismatic deviation in primary and lateral gaze, and resolution of premium non-prescription eyewear available for over the counter purchase to consumers at local optical shops or stores. 48 pairs oflocally purchased sun eyewear from prominent national brands were purchased for this study. Two principal investigators measured both lenses in each pair of sun eyewear for refractive error and cylinder using a calibrated 8 power telescope. Prismatic deviation was measured on both lenses of each eyewear in primary gaze and 30 degrees dextroversional gaze. Resolution was also obtained for each individual lens by using the same calibrated 8 power telescope and the standard high contrast NBS Definition Pattern. All eyewear within the study produced measurable amounts of refractive power, with a majority oflenses measured producing a low minus power. Cylinder was also found in all lenses. Most lenses induced base-down and base-out prismatic deviations for primary gaze, and most lenses gave a base-out horizontal vergence effect in primary gaze. All but one lens produced base-out prism with temporal gaze and all lenses produced base-in prism in nasal gaze giving a yoked prismatic effect in lateral gazes. The majority of vertical deviations in lateral gaze were base-down. Resolution results showed large variability between lenses within the tested eyewear with over a third of the lenses not meeting current ANSI standards. It was concluded that refractive power and induced cylinder in all the lenses tested would have minimal perceptual effect based on the depth of focus innate in the human eye with variability and sensitivity most likely based on pupil size secondary to tint density. Prismatic deviations were felt to have a more detrimental effect on the viewer due to changes in perception of the viewer\u27s environment. Resolution results were questionable based on variability in tint density and transmittance of individual lenses. Further investigation in areas of transmittance and tint are indicated in determining resolving capabilities of sun eyewear. Further testing in optical quality is also indicated and could include subjective responses to clarity and comfort in both recreational and professional athletes