1,100 research outputs found

    Regional polycentricity: an indicator framework for assessing cohesion impacts of railway infrastructures

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    Territorial cohesion has become one of the main objectives in transport planning. This has fostered the development of assessment methodologies to quantitatively estimate the territorial impact of major transport infrastructures, which are particularly scarce at the intra-regional level. Linked to cohesion, polycentricity has been defined as the best spatial configuration to achieve balanced regions where population and opportunities are distributed among several entities linked by functional relationships. This paper aims to present a methodology to estimate these impacts based on the use of a new regional composite polycentricity indicator. The proposed indicator is tested by comparing the effects of conventional and high-speed railway (HSR) alternatives in the territorial system of a northern region of Spain. This quantitative assessment is a ranking tool for prioritizing rail network alternatives in terms of achieving the most balanced territory, which is especially relevant in countries where HSR networks follow cohesion goals. Our results show that new HSR links should only be complementary to regional railway services, and that the suppression of secondary lines should be avoided if a reduction in polarization is to be achieved.E. González-González gratefully acknowledges a predoctoral fellowship (FPI) from the Spanish Ministry of Science and Innovation (reference BES-2008–00436)

    Protocol Techniques for Testing Radiotherapy Accelerators

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    The nature of radiotherapy accelerators is briefly explained. It is argued that these complex safety-critical systems need a systematic basis for testing their software. The paper describes a novel application of protocol specification and testing methods to radiotherapy accelerators. An outline specification is given in LOTOS (Language Of Temporal Ordering Specification) of the accelerator control system. It is completely infeasible to use this directly for test generation. Instead, specification inputs are restricted using annotations in a Parameter Constraint Language. This is automatically translated into LOTOS and combined with the accelerator specification. It then becomes manageable to generate tests automatically of the actual accelerator to check that it agrees with its specification according to the relation ioconf (input-output conformance). Sample input annotations, their translation to LOTOS, and the resulting test cases are described

    A proposed methodology for the assessment of arsenic, nickel, cadmium and lead levels in ambient air

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    Air quality assessment, required by the European Union (EU) Air Quality Directive, Directive 2008/50/EC, is part of the functions attributed to Environmental Management authorities. Based on the cost and time consumption associated with the experimental works required for the air quality assessment in relation to the EU-regulated metal and metalloids, other methods such as modelling or objective estimation arise as competitive alternatives when, in accordance with the Air Quality Directive, the levels of pollutants permit their use at a specific location. This work investigates the possibility of using statistical models based on Partial Least Squares Regression (PLSR) and Artificial Neural Networks (ANNs) to estimate the levels of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in ambient air and their application for policy purposes. A methodology comprising the main steps that should be taken into consideration to prepare the input database, develop the model and evaluate their performance is proposed and applied to a case of study in Santander (Spain). It was observed that even though these approaches present some difficulties in estimating the individual sample concentrations, having an equivalent performance they can be considered valid for the estimation of the mean values - those to be compared with the limit/target values - fulfilling the uncertainty requirements in the context of the Air Quality Directive. Additionally, the influence of the consideration of input variables related to atmospheric stability on the performance of the studied statistical models has been determined. Although the consideration of these variables as additional inputs had no effect on As and Cd models, they did yield an improvement for Pb and Ni, especially with regard to ANN models.This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through the Projects CTM2010-16068 and CTM2013-43904R. Germán Santos thanks MINECO for his FPI research fellowship (BES-2011-047908)

    The systemic lupus erythematosus IRF5 risk haplotype is associated with systemic sclerosis

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    Systemic sclerosis (SSc) is a fibrotic autoimmune disease in which the genetic component plays an important role. One of the strongest SSc association signals outside the human leukocyte antigen (HLA) region corresponds to interferon (IFN) regulatory factor 5 (IRF5), a major regulator of the type I IFN pathway. In this study we aimed to evaluate whether three different haplotypic blocks within this locus, which have been shown to alter the protein function influencing systemic lupus erythematosus (SLE) susceptibility, are involved in SSc susceptibility and clinical phenotypes. For that purpose, we genotyped one representative single-nucleotide polymorphism (SNP) of each block (rs10488631, rs2004640, and rs4728142) in a total of 3,361 SSc patients and 4,012 unaffected controls of Caucasian origin from Spain, Germany, The Netherlands, Italy and United Kingdom. A meta-analysis of the allele frequencies was performed to analyse the overall effect of these IRF5 genetic variants on SSc. Allelic combination and dependency tests were also carried out. The three SNPs showed strong associations with the global disease (rs4728142: P = 1.34×10<sup>−8</sup>, OR = 1.22, CI 95% = 1.14–1.30; rs2004640: P = 4.60×10<sup>−7</sup>, OR = 0.84, CI 95% = 0.78–0.90; rs10488631: P = 7.53×10<sup>−20</sup>, OR = 1.63, CI 95% = 1.47–1.81). However, the association of rs2004640 with SSc was not independent of rs4728142 (conditioned P = 0.598). The haplotype containing the risk alleles (rs4728142*A-rs2004640*T-rs10488631*C: P = 9.04×10<sup>−22</sup>, OR = 1.75, CI 95% = 1.56–1.97) better explained the observed association (likelihood P-value = 1.48×10<sup>−4</sup>), suggesting an additive effect of the three haplotypic blocks. No statistical significance was observed in the comparisons amongst SSc patients with and without the main clinical characteristics. Our data clearly indicate that the SLE risk haplotype also influences SSc predisposition, and that this association is not sub-phenotype-specific

    Drivers of airport scheduled traffic in European winter tourism areas:Infrastructure, accessibility, competition and catchment area

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    Ski resorts in Europe are major tourism destinations that can generate traffic for their local airports. These small mountain airports can offer the airlines unparalleled accessibility to the resorts, but their catchment areas are typically not well populated. Local authorities are keen to develop scheduled flights but have failed many times in the past. In this context, there is no previous study that analyses the drivers of scheduled airport traffic in winter tourism regions. To that end, we compiled a large dataset of European airports and ski resorts and carry out a Poisson regression. Results show that catchment area, competition, and infrastructure outweigh accessibility to ski resorts as the main drivers of scheduled traffic at small mountain airports. This is linked to the dominance of low-cost carriers that prefer to operate out of major airports with larger aircraft. Small airports are recommended to focus on premium markets with smaller aircraft

    Assessment of the Public Administration Tools for the improvement of the Eco-efficiency of Small and Medium Sized Enterprises

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    Small and Medium Sized Enterprises (SME) face barriers to the implementation and development of eco-efficiency that could be overcome taking advantage of the adequate stimuli and incentives. A previous research and a thorough literature analysis show Public Administration (PA) is a key stakeholder. PA could use better its tools to stimulate SME to improve their ecoefficiency. Among these tools it can be named well known command and control tools like legislation or taxes, but also price policies, green procurement, ecological education, eco-innovation support and others. This paper reviews these tools and how they contribute to overcome barriers to ecoefficiency by offering external and internal incentives for SME. The analysis is focused on the case of Venezuelan public administration and SME but it can be generalized to other case studies. In addition, a panel of experts validates the results and assesses the public administration tools by means of the policy Delphi method. The assessment is based on criteria like: market influence, capability of the public administration for controlling results, tool costs, impact on public administration image, timespan to get results, etc. The assessment, therefore, allows ranking and understanding the tools according to their effectiveness and efficiency to support SME to improve their ecoefficiency. Due to the specific characteristics of the case study: SME of Venezuela, the method shows the best mix of public administration tools includes mainly command and control tools. Also the mix includes certain new-approach tools like advertising about responsible consumption and eco-efficient products, or education/training in environmental responsibility. The method also allows understanding better how the tools will help accomplishing the objectives for ecoefficiency of the public administration. Therefore, this research provides a method for raising information to be used when planning the actions to improve eco-efficiency of the SME.Fernández-Viñé, MB.; Gómez-Navarro, T.; Capuz-Rizo, SF. (2013). Assessment of the Public Administration Tools for the improvement of the Eco-efficiency of Small and Medium Sized Enterprises. Journal of Cleaner Production. 47:265-273. doi:10.1016/j.jclepro.2012.08.026S2652734

    Cortisol secretion after adrenocorticotrophin (ACTH) and Dexamethasone tests in healthy female and male dogs

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    <p>Abstract</p> <p>Background</p> <p>For the conclusive diagnosis of Cushing's Syndrome, a stimulating ACTH test or a low suppressive Dexamethasone test is used. Reports in other species than the dog indicate that plasma cortisol concentration after ACTH administration is affected by gender. We investigated the effect of gender on the cortisol response to ACTH and Dexamethasone tests in dogs.</p> <p>Methods</p> <p>Seven healthy adult Cocker Spaniels (4 females and 3 males) were assigned to a two by two factorial design: 4 dogs (2 females and 2 males) received IV Dexamethasone 0.01 mg/kg, while the other 3 dogs received an IV saline solution (control group). Two weeks later the treatments were reversed. After one month, ACTH was given IV (250 μg/animal) to 4 dogs (2 female and 2 males) while the rest was treated with saline solution (control group). Cortisol concentrations were determined by a direct solid-phase radioimmunoassay and cholesterol and triglycerides by commercial kits.</p> <p>Results and Discussion</p> <p>No effect of treatment was observed in metabolite concentrations, but females presented higher cholesterol concentrations. ACTH-treated dogs showed an increase in cortisol levels in the first hour after sampling until 3 hours post injection. Cortisol concentrations in Dexamethasone-treated dogs decreased one hour post injection and remained low for 3 hours, thereafter cortisol concentrations increased. The increase in cortisol levels from one to two hours post ACTH injection was significantly higher in females than males. In Dexamethasone-treated males cortisol levels decreased one hour post injection up to 3 hours; in females the decrease was more pronounced and prolonged, up to 5 hours post injection.</p> <p>Conclusion</p> <p>We have demonstrated that cortisol response to ACTH and Dexamethasone treatment in dogs differs according to sex.</p
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