1,100 research outputs found
Regional polycentricity: an indicator framework for assessing cohesion impacts of railway infrastructures
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)
Antibacterial activity of crude extracts from Mexican plants against methicillin-resistant Staphylococcus
The aim of this study was to evaluate the antimicrobial activity of 36 extracts from 18 vegetal species used as soap, insecticides, insect repellent and for the treatment of several diseases likely associated to microorganisms. The vegetal species were collected in Oaxaca, Puebla and Veracruz States, México. The extracts were evaluated against isolates of nosocomial infections of Staphylococcus aureus and Staphylococcus coagulase negative resistant to Methicillin by a modificated agar diffusion method. The results demonstrate an important antibacterial effect in vitro, against all of the strains of Staphylococcus tested mainly with those from Vernonanthura oaxacana, Trixis silvatica, and with those of Perezia hebeclada. The minimum inhibitory concentration for V. oaxacana and P. hebeclada was 250 μg/disc and for T. silvatica it was 15 μg/disc. These extracts showed an important potential that would contribute to the development of new agents against infections by Staphylococcus.Key words: Crude extracts, antimicrobial activity, intrahospitalary infections, methicillin-resistant Staphylococcus coagulase negative
Improvement of the drought indicators system in the Jucar River Basin, Spain
[EN] Droughts are one of the gravest natural threats currently existing in the world and their occurrence and intensity might be exacerbated in the coming years due to climate change. The severe impacts that droughts cause to inland water resources and to the associated socio-economic activities justify the continuous monitoring of the drought. The case study presented shows a practical application of a distributed drought monitoring system implemented in a real river basin district, the Jucar River Basin District (43,000 km(2)), where drought periods of marked intensity have occurred historically and the climate ranges from humid in the north to semiarid in the south. Five drought indices have been applied: Standardised Precipitation Index (SPI) for meteorological drought; Palmer Drought Severity Index (PDSI) and a newsoilmoisture index (HI), for edaphic drought; Normalised Difference Vegetation Index (NDVI) for the vegetation activity; and Spanish Status Index (SI), for the operational drought. All indices are standardised to compare them.
The relationship between the standardised operational drought index SI and the long-term meteorological indices, SPI-12 or SPI-24, show that in a medium size basin the concept of "prolonged drought" required by the European Commission under the Water Framework Directive could be defined by the use of accumulated precipitation indices. The number of months to be accumulated depends on the size of the basin and the water management system properties. In large basins, such as the Jcar river basin (22,000 km(2)), there are significant deviations due to the spatial distribution of the drought. The use of a unique aggregated indicator could hide a significant drought in a specific area, or on the other hand showa non-real drought. Evolution of drought indices for eachwater management systemmust be accompanied by spatially distributed drought maps to better understand the drought status and its evolution.Tatiana Ortega; Pérez-Martín, MÁ.; Estrela Monreal, T. (2018). Improvement of the drought indicators system in the Jucar River Basin, Spain. The Science of The Total Environment. 610:276-290. https://doi.org/10.1016/j.scitotenv.2017.07.250S27629061
Integrated multi-modality image-guided navigation for neurosurgery: open-source software platform using state-of-the-art clinical hardware.
PURPOSE: Image-guided surgery (IGS) is an integral part of modern neuro-oncology surgery. Navigated ultrasound provides the surgeon with reconstructed views of ultrasound data, but no commercial system presently permits its integration with other essential non-imaging-based intraoperative monitoring modalities such as intraoperative neuromonitoring. Such a system would be particularly useful in skull base neurosurgery. METHODS: We established functional and technical requirements of an integrated multi-modality IGS system tailored for skull base surgery with the ability to incorporate: (1) preoperative MRI data and associated 3D volume reconstructions, (2) real-time intraoperative neurophysiological data and (3) live reconstructed 3D ultrasound. We created an open-source software platform to integrate with readily available commercial hardware. We tested the accuracy of the system's ultrasound navigation and reconstruction using a polyvinyl alcohol phantom model and simulated the use of the complete navigation system in a clinical operating room using a patient-specific phantom model. RESULTS: Experimental validation of the system's navigated ultrasound component demonstrated accuracy of [Formula: see text] and a frame rate of 25 frames per second. Clinical simulation confirmed that system assembly was straightforward, could be achieved in a clinically acceptable time of [Formula: see text] and performed with a clinically acceptable level of accuracy. CONCLUSION: We present an integrated open-source research platform for multi-modality IGS. The present prototype system was tailored for neurosurgery and met all minimum design requirements focused on skull base surgery. Future work aims to optimise the system further by addressing the remaining target requirements
EXTRACCIÓN DE COMPUESTOS FENÓLICOS DE LA CÁSCARA DE LIMA (Citrus limetta Risso) Y DETERMINACIÓN DE SU ACTIVIDAD ANTIOXIDANTE
Los desechos que se tienen de la obtención de jugos son principalmente cáscara y bagazo, sin embargo son una buena fuente de compuestos fenólicos, mayoritariamente de flavonoides. El objetivo de este trabajo fue extraer y cuantificar el contenido fenólico de la cáscara de lima, así como su actividad antioxidante. Esto se determinó evaluando el mejor sistema de extracción de compuestos fenólicos y flavonoides, teniendo como variables: tipo de solvente (metanol, acetona y hexano) y tamaño de partícula (tamiz 20 (T1) y 50 (T2)). La determinación de la actividad antioxidante se realizó mediante dos métodos ABTS•+ y DPPH•, comparando la efectividad entre ellos. El mejor modelo de extracción de los compuestos fenólicos y flavonoides fue utilizando metanol como solvente y un tamaño de partícula pequeño (300 μm). El valor más alto de actividad antioxidante (91,69 %) se obtuvo con el método ABTS•+, en los extractos con metanol y acetona, sin diferencias entre los tamices utilizados. La cáscara de lima tiene 8,79 mg EAG/g ms y 14,325 mg quercetina/g ms. La utilización de cáscara de lima representa una alternativa para el aprovechamiento de biocompuestos, que son considerados como sustitutos de los antioxidantes sintéticos existentes
Influence of Two Vaccination Campaigns on Genetic Diversity of Invasive Neisseria meningitidis Isolates in Northern Spain (1997–2008)
BACKGROUND: Neisseria meningitidis diversifies rapidly, due to its high recombination rates. The aim of this study was to analyze the possible impact of two vaccination campaigns (a once-off A/C polysaccharide vaccination campaign in people aged 18 months to 20 years old in 1997, and a meningococcal C conjugate vaccination campaign in children aged < or = 6 years old from 2000 to 2008) on diversification of the population of invasive isolates obtained between 1997 and 2008. All of the 461 available isolates were included (2, 319, 123, 11 and 6 belonging to serogroups A, B, C, Y and W-135, respectively). METHODOLOGY/PRINCIPAL FINDINGS: The isolates were analyzed for diversity using multilocus sequence typing, eBURST and the S.T.A.R.T.2 program. One hundred and seven sequence types (ST) and 20 clonal complexes were obtained. Five different STs (ST11, ST8, ST33, ST1163 and ST3496) included 56.4% of the isolates. With the exception of ST11, all other STs were associated with a specific serogroup. Epidemic circulation of serogroup C ST8 isolates was detected in 1997-1998, as well as epidemic circulation of ST11 isolates (serogroups B and C) in 2002-2004. The epidemic behavior of serogroup B ST11 (ST11_B:2a:P1.5) was similar, although with lesser intensity, to that of ST11 of serogroup C. Although clonality increased during epidemic years, the overall diversity of the meningococcal population did not increase throughout the 12 years of the study. CONCLUSION: The overall diversity of the meningococcal population, measured by the frequency of STs and clonal complexes, numbers of alleles, polymorphic sites, and index of association, remained relatively constant throughout the study period, contradicting previous findings by other researchers
Water accounting for stressed river basins based on water resources management models
[EN] Water planning and the Integrated Water Resources Management (IWRM) represent the best way to help decision makers to identify and choose the most adequate alternatives among other possible ones. The System of Environmental-Economic Accounting for Water (SEEA-W) is displayed as a tool for the building of water balances in a river basin, providing a standard approach to achieve comparability of the results between different territories. The target of this paper is to present the building up of a tool that enables the combined use of hydrological models and water resources models to fill in the SEEA-W tables. At every step of the modelling chain, we are capable to build the asset accounts and the physical water supply and use tables according to SEEA-W approach along with an estimation of the water services costs. The case study is the Jucar River Basin District (RBD), located in the eastern part of the Iberian Peninsula in Spain which as in other many Mediterranean basins is currently water-stressed. To guide this work we have used PATRICAL model in combination with AQUATOOL Decision Support System (DSS). The results indicate that for the average year the total use of water in the district amounts to 15,143 hm3/year, being the Total Water Renewable Water Resources 3909 hm3/year. On the other hand, the water service costs in Jucar RBD amounts to 1634 million per year at constant 2012 prices. It is noteworthy that 9% of these costs correspond to non-conventional resources, such as desalinated water, reused water and water transferred from other regions.The authors thank the anonymous reviewers for their valuable comments, suggestions and positive feedback. All remaining errors, however, are solely the responsibility of the authors. We would also like to express our gratitude to the Jucar River Basin Authority – Confederación Hidrográfica del Júcar (Spanish Ministry of Agriculture, Food and Environment) for providing data to develop this study. The authors wish to thank the Spanish Ministry of Economy and Competitiveness for its financial support through the NUTEGES project (CGL2012-34978). We also value the support provided by the European Community's Seventh Framework Program in financing the projects ENHANCE (FP7-ENV2012, 308438) and IMPREX (H2020-WATER-2014-2015, 641811).Pedro Monzonís, M.; Solera Solera, A.; Ferrer Polo, FJ.; Andreu Álvarez, J.; Estrela Monreal, T. (2016). Water accounting for stressed river basins based on water resources management models. The Science of The Total Environment. 565:181-190. https://doi.org/10.1016/j.scitotenv.2016.04.161S18119056
Environmental noise control during its transmission phase to protect buildings. Design model for acoustic barriers based on arrays of isolated scatterers
A new generation of acoustic barriers is being introduced into the noise control market. These barriers,
based on arrays of isolated scatterers, present interesting properties to be used in cities to reduce the
transmitted transport noise affecting buildings. Among them, both aesthetic and continuity factors of the
urban landscape may be mentioned. This new kind of barrier is technologically advanced and acoustically
competitive with respect to the current ones formed by continuous rigid materials. To design these
barriers whilst taking into account their inherent acoustic complexity, we present an overlapping numerical
model here that enables us to split the real three-dimensional problem into two twodimensional
ones, allowing both the reduction of the computational cost and the separate analysis of each one of the noise control mechanisms involved. We analyse different cases, checking the numerical simulations with accurate experimental results.This work is supported by MEC (Spanish Government) under grant No. MTM2012-36740-C02-02.Castiñeira Ibáñez, S.; Rubio Michavila, C.; Sánchez Pérez, JV. (2015). Environmental noise control during its transmission phase to protect buildings. Design model for acoustic barriers based on arrays of isolated scatterers. Building and Environment. 93:179-185. https://doi.org/10.1016/j.buildenv.2015.07.002S1791859
Development and validation of a liquid chromatography-tandem mass spectrometry method for the determination of nicotine and its metabolites in placenta and umbilical cord.
Tobacco exposure during pregnancy is associated with obstetric and fetal complications. This study developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyse the placenta (PL) and umbilical cord (UC) for nicotine, cotinine and hydroxycotinine (OH-cotinine). Specimens were homogenized in water, followed by solid-phase extraction. Chromatographic separation was performed using an Atlantis HILIC Silica column. Detection was accomplished in electrospray in positive mode. Method validation included: linearity (5 to 1000 ng/g), accuracy (86.9 to 105.2% of target concentration in PL, and 89.1 to 105.0% in UC), imprecision (6.8 to 11.8% in PL, and 7.6 to 12.2% in UC), limits of detection (2 ng/g for cotinine and OH-cotinine, and 5 ng/g for nicotine) and quantification (5 ng/g), selectivity (no endogenous or exogenous interferences), matrix effect (-34.1 to -84.5% in PL, %CV = 9.1-24.0%; -18.9 to -84.7% in UC, %CV = 10.2-23.9%), extraction efficiency (60.7 to 131.5% in PL, and 64.1 to 134.2% in UC), and stability 72 h in the autosampler ( < 11.5% loss in PL, and < 13% loss in UC). The method was applied to 14 PL and UC specimens from tobacco users during pregnancy. Cotinine (6.8-312.2 ng/g in PL; 6.7-342.3 ng/g in UC) was the predominant analyte, followed by OH-cotinine ( < LOQ-80.2 ng/g in PL; < LOQ-80.5 ng/g in UC) and nicotine (5.7-63.7 ng/g in PL; 5.1-63.3 ng/g in UC). In a future study, this method will be applied to more than 150 specimens collected from a wide clinical study to evaluate the usefulness of maternal hair, meconium, placenta and umbilical cord compared to the maternal interview to detect in utero drug exposure
FSSIM, a bio-economic farm model for simulating the response of EU farming systems to agricultural and environmental policies
The disciplinary nature of most existing farm models as well as the issue specific orientation of most of the studies in agricultural systems research are main reasons for the limited use and re-use of bio-economic modelling for the ex-ante integrated assessment of policy decisions. The objective of this article is to present a bio-economic farm model that is generic and re-usable for different bio-physical and socio-economic contexts, facilitating the linking of micro and macro analysis or to provide detailed analysis of farming systems in a specific region. Model use is illustrated in this paper with an analysis of the impacts of the CAP reform of 2003 for arable and livestock farms in a context of market liberalization. Results from the application of the model to representative farms in Flevoland (the Netherlands) and Midi-Pyrenees (France) shows that CAP reform 2003 under market liberalization will cause substantial substitution of root crops and durum wheat by vegetables and oilseed crops. Much of the set-aside area will be put into production intensifying the existing farming systems. Abolishment of the milk quota system will cause an increase of the average herd size. The average total gross margin of farm types in Flevoland decreases while the average total gross margin of farms in Midi-Pyrenees increases. The results show that the model can simulate arable and livestock farm types of two regions different from a bio-physical and socio-economic point of view and it can deal with a variety of policy instruments. The examples show that the model can be (re-)used as a basis for future research and as a comprehensive tool for future policy analysis
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