Effects of industrial polystyrene foam insulation pads on the center of pressure and load distribution in the forefeet of clinically normal horses

Objective—To evaluate the ability of industrial polystyrene foam insulation pads to redistribute loads placed on clinically normal weight-bearing structures of the foot and shift the location of the center of pressure palmarly in horses. Animals—25 nonlame mature horses. Procedures—Both forefeet from each horse were evaluated. Center of pressure data and solar load distribution patterns were recorded during a 5-second trial by use of a commercial pressure measurement system prior to placement of foam sole support and at 0, 6, 12, 24, and 48 hours after placement. Total contact surface area, contact pressure, peak contact pressure, and center of pressure positions were compared by use of a linear mixed model with repeated measurements. Results—Total contact surface area was increased significantly at all time points, whereas contact pressure and peak contact pressure were significantly decreased at all time points following application of foam sole supports. Immediately following application of sole support, the position of the center of pressure was significantly moved cranially. However, by 48 hours, the center of pressure was significantly positioned more palmarly than prior to application of the foam supports. Conclusions and Clinical Relevance—Results indicated that the use of foam sole supports may be an effective, economical, and immediate treatment for acute laminitis

The impact of regional jets on air service at selected US airports and markets

Regional jets, normally defined as jet aircraft introduced since 1993 with less than 100 seats, have been thought to have significant impacts on air services at airports, for example, in improving service frequency, allowing airlines to exploit niche markets and to feed hubs. Previous studies have focused on regional jet deployment strategy and the overall situation and they suggest that deployment was generally to larger cities first and, in addition, to locations east of the Mississippi. It has also been suggested that smaller airports might lose service when regional jets replace turbo-props and that carrier competition would increase, to the benefit of the consumer. This paper aims to throw more light on these issues from the individual airports’ point of view. Data on changes in schedules from the Official Airline Guide (OAG) at a series of case study airports from 1994 to 2002 is used to examine, the impacts on new route development, market dynamics, carrier competition and concentration and deployment status. In particular, the impact on smaller airports is examined. It is concluded, subject to the usual caveats on sample size, that there is little evidence of a uniform impact on routes or airports. The aggregate picture often described by the industry and government is shown to be a combination of highly dissimilar cases. A spectrum of effects is identified across different types of airports and routes but some of the anticipated trends, such as hub bypassing, are not observed. Some airports reaped significant benefits in terms of improved frequency and services to new destinations, whilst others gained little

The development of a more risk-sensitive and flexible airport safety area strategy: Part II. Accident location analysis and airport risk assessment case studies

This two-part paper presents the development of an improved airport risk assessment methodology aimed at assessing risks related to aircraft accidents at and in the vicinity of airports and managing Airport Safety Areas (ASAs) as a risk mitigation measure. The improved methodology is more quantitative, risk-sensitive, flexible and transparent than standard risk assessment approaches. As such, it contributes to the implementation of Safety Management Systems at airports, as stipulated by the International Civil Aviation Organisation. The second part of the paper presents the analysis of accident locations, including the plotting of Complementary Cumulative Probability Distributions for the relevant accident types. These were then used in conjunction with the improved accident frequency models to produce Complementary Cumulative Frequency Distributions that could be used to assess risks related to specific runways and determine Airport Safety Area (ASA) dimensions necessary to meet a quantitative target level of safety. The approach not only takes into account risk factors previously ignored by standard risk assessments but also considers the operational and traffic characteristics of the runway concerned. The use of the improved risk assessment technique and risk management strategy using ASAs was also demonstrated in two case studies based on New York LaGuardia Airport and Boca Raton Airport in Florida

The development of a more risk-sensitive and flexible airport safety area strategy: Part I. The development of an improved accident frequency model

This two-part paper presents the development of an improved airport risk assessment methodology aimed at assessing risks related to aircraft accidents at and in the vicinity of airports and managing Airport Safety Areas (ASAs) as a risk mitigation measure. The improved methodology is more quantitative, risk-sensitive, flexible and transparent than standard risk assessment approaches. As such, it contributes to the implementation of Safety Management Systems at airports, as stipulated by the International Civil Aviation Organisation. The first part of the paper presents the methodological advances made in the development of accident frequency models; namely the building of a single comprehensive database of all relevant accident types, the collection and use of normal operations data in quantifying the criticality of a series of risk factors, and modelling accident frequency using multivariate logistic regression. The resulting models have better goodness-of-fit, sensitivity and specificity than standard risk assessment methodologies

Quantifying and characterising aviation accident risk factors

This paper compares normal flights’ exposure to a number of meteorological factors with the equivalent for certain accident flights. The factors examined include visibility, ceiling height, temperature, crosswind, tailwind and instrument or visual meteorological conditions. Differences in exposure and to measure accident propensity related to different levels of risk exposure are quantified based on relative accident involvement ratios. Four categories of aircraft accidents relevant to the assessment of airport safety are examined

Modelling the location and consequences of aircraft accidents

Following the completion of two projects funded by the UK EPSRC and two for the Airports Cooperative Research Program, ACRP (2008, 2011), this paper aims to summarise the work on the location and consequence models . The projects overall focused on the development of an improved airport risk assessment methodology aimed at assessing risks related to aircraft accidents at and in the vicinity of airports and managing Runway Safety Areas (RSAs) as a risk mitigation measure. The improved methodology is more quantitative, risk-sensitive, flexible and transparent than traditional risk assessment approaches. As such, it contributes to the implementation of Safety Management Systems at airports, as stipulated by the International Civil Aviation Organisation. The innovative elements of this research are two-fold. First, an accident database covering undershoots, overruns, and veer-off crashes close to runways at airports has been compiled and data on incidents has been added. Second, accident frequency models have been developed, for example, identifying the contribution of influencing factors such as variations in meteorological conditions. To allow airport risk to then be calculated entails comparing these cases with those contained in a ‘normal operations database’ where no accidents have been recorded but where the influencing factors are also known. Subsequent models have examined the location of the accidents and their consequences. It is this work that is the focus of this paper. Future work will focus on improving these aspects of the modelling and the consequences of crashes more than 2000 ft. but less than 10 miles from a runway end as well as impacts on third parties

Painting the Nation:Examining the Intersection Between Politics and the Visual Arts Market in Emerging Economies

Politics and art have throughout history, intersected in diverse and complex ways. Ideologies and political systems have used the arts to create a certain image and, depending on the form of government this has varied from clear-cut state propaganda, to patronage, to more indirect arms-length funding procedures. Therefore, artists working within the macro-level socio-political context cannot help but be influenced, inspired and sometimes restricted by these policies and political influences. This article examines the contemporary art markets of two emerging, Socialist economies to investigate the relationship between state pol-itics and the contemporary visual arts market. We argue that the respective governments and art worlds are trying to construct a brand narrative for their nations, but that these discourses are often at cross-purposes. In doing so, we illustrate that it is impos-sible to separate a consideration of the artwork from the macro-level context in which it is produced, distributed, and consumed

Positively Selected Codons in Immune-Exposed Loops of the Vaccine Candidate OMP-P1 of Haemophilus influenzae

The high levels of variation in surface epitopes can be considered as an evolutionary hallmark of immune selection. New computational tools enable analysis of this variation by identifying codons that exhibit high rates of amino acid changes relative to the synonymous substitution rate. In the outer membrane protein P1 of Haemophilus influenzae, a vaccine candidate for nontypeable strains, we identified four codons with this attribute in domains that did not correspond to known or assumed B- and T-cell epitopes of OMP-P1. These codons flank hypervariable domains and do not appear to be false positives as judged from parsimony and maximum likelihood analyses. Some closely spaced positively selected codons have been previously considered part of a transmembrane domain, which would render this region unsuited for inclusion in a vaccine. Secondary structure analysis, three-dimensional structural database searches, and homology modeling using FadL of E. coli as a structural homologue, however, revealed that all positively selected codons are located in or near extracellular looping domains. The spacing and level of diversity of these positively selected and exposed codons in OMP-P1 suggest that vaccine targets based on these and conserved flanking residues may provide broad coverage in H. influenzae