Search results for " Location"
showing 10 items of 403 documents
Determination of Concentration Profiles of Methyl Mercury Compounds in Surface Waters of Polar and other Remote Oceans by GC-AFD
1998
Abstract The concentration of monomethyl mercury (MeHg+) and dimethyl mercury (Me2Hg) was determined in surface sea-water samples of the Antarctic and Arctic Ocean as well as of other remote areas (South Atlantic and South Pacific) during expeditions of the German research vessel “Polarstern”. A purge and trap/gas chromatographic system, equipped with an atomic fluorescence detector (AFD), was used. For the analysis of MeHg+ conversion into the volatile methylethyl mercury by reaction with tetraethyloborate prior to the purging process was carried out. The detection limit for both methylated mercury compounds was 5 pg Hg/L, which allowed their determination in most ocean water samples even …
Reflexiones sobre cómo evaluar y mejorar la respuesta a la pandemia de COVID-19
2020
La pandemia de COVID-19 ha afectado de manera particularmente intensa a España, pese a su nivel de desarrollo y la elogiada solidez de su Sistema Nacional de Salud. Para comprender qué ha pasado e identificar cómo mejorar la respuesta creemos imprescindible una evaluación independiente multidisciplinaria de la esfera sanitaria, política y socioeconómica. En este trabajo proponemos objetivos, principios, metodología y dimensiones a evaluar, además de esbozar el tipo de resultados y conclusiones esperadas. Nos inspiramos en los requerimientos formulados por el panel independiente de la Organización Mundial de la Salud y en las experiencias evaluativas en otros países, y detallamos la propuest…
The contribution of geographical certification programs to farm income and rural economies: The case of Pecorino Siciliano PDO
2021
This study attempts to measure the capacity of the EU geographical certification scheme to positively influence the price of certified products and the incomes of their producers. A comparison of the economic results of two cheese-producing dairy farm enterprises with different business strategies and locations within the Sicilian hinterlands is performed in order to determine the transformation value of each dairy’s sheep milk into pecorino cheese (with and without the Protected Designation of Origin, or PDO, certification) and the related joint products (ricotta). The economic convenience of the total transformation of sheep milk into Pecorino Siciliano PDO and ricotta is also appraised. …
A Branch-and-Cut method for the Capacitated Location-Routing Problem
2011
International audience; Recent researches in the design of logistic networks have shown that the overall distribution cost may be excessive if routing decisions are ignored when locating depots. The Location-Routing Problem (LRP) overcomes this drawback by simultaneously tackling location and routing decisions. The aim of this paper is to propose an exact approach based on a Branch-and-Cut algorithm for solving the LRP with capacity constraints on depots and vehicles. The proposed method is based on a zero-one linear model strengthened by new families of valid inequalities. The computational evaluation on three sets of instances (34 instances in total), with 5–10 potential depots and 20–88 …
Discrimination based on place of residence and access to employment
2014
International audience; The purpose of this study is to assess the degree of employment discrimination against young people according to their place of residence. We considered several spatial scales in order to measure the effect of the reputation of the administrative department or county, the town or municipality and of the local neighbourhood. The evaluation is performed using correspondence test data carried out between October 2011 and February 2012. We studied 2988 candidacies that were submitted to 498 job offers (waiters and cooks) within the restaurant industry and located in the Paris area. Statistical and econometric results pointed out that resident effect is significant and im…
Sampling properties of the Bayesian posterior mean with an application to WALS estimation
2022
Many statistical and econometric learning methods rely on Bayesian ideas, often applied or reinterpreted in a frequentist setting. Two leading examples are shrinkage estimators and model averaging estimators, such as weighted-average least squares (WALS). In many instances, the accuracy of these learning methods in repeated samples is assessed using the variance of the posterior distribution of the parameters of interest given the data. This may be permissible when the sample size is large because, under the conditions of the Bernstein--von Mises theorem, the posterior variance agrees asymptotically with the frequentist variance. In finite samples, however, things are less clear. In this pa…
Physiological and practical considerations on liver regeneration after liver transplantion
2019
La regeneración hepática ha sido uno de los procesos más estudiados en la medicina al ser el hígado un órgano altamente importante y complejo del organismo, asiento de múltiples enfermedades y expuesto por su ubicación anatómica a los traumatismos. El trasplante hepático se ha convertido en uno de los procedimientos más frecuentes en la trasplantología de órganos, por lo que el conocimiento de los aspectos básicos de esta técnica terapéutica y el estudio de los mecanismos histológicos y fisiológicos vinculados con la regeneración hepática, es fundamental para lograr un resultado satisfactorio. Se realizó un estudio exploratorio de la bibliografía vinculada con el tema, con el objetivo de ex…
The impact of winter flooding with saline water on foliar carbon uptake and the volatile fraction of leaves and fruits of lemon (Citrus limon) trees
2012
We investigated the consequences of recurrent winter flooding with saline water on a lemon (Citrus × limon (L.) Burm.f.) orchard, focussing on photosynthesis limitations and emission of secondary metabolites (isoprenoids) from leaves and fruits. Measurements were carried out immediately after flooding (December), at the end of winter (April) and after a dry summer in which plants were irrigated with optimal quality water (September). Photosynthesis was negatively affected by flooding. The effect was still visible at the end of winter, whereas the photosynthetic rate was fully recovered after summer, indicating an unexpected resilience capacity of flooded plants. Photosynthesis inhibition by…
Atrial Fibrosis Hampers Non-invasive Localization of Atrial Ectopic Foci From Multi-Electrode Signals: A 3D Simulation Study
2018
[EN] Introduction: Focal atrial tachycardia is commonly treated by radio frequency ablation with an acceptable long-term success. Although the location of ectopic foci tends to appear in specific hot-spots, they can be located virtually in any atrial region. Multi-electrode surface ECG systems allow acquiring dense body surface potential maps (BSPM) for non-invasive therapy planning of cardiac arrhythmia. However, the activation of the atria could be affected by fibrosis and therefore biomarkers based on BSPM need to take these effects into account. We aim to analyze the effect of fibrosis on a BSPM derived index, and its potential application to predict the location of ectopic foci in the …
Simple Circuit Models for Studying Global Earthing Systems
2007
The paper proposes three simple circuit models for the simulation of the behaviour of a global earthing system during different fault events. The models allow one the evaluation of the maximum earth potential rise at every possible fault location and for every possible fault event. The three considered fault events are: single-line-to-earth fault inside a MV/LV substation, double-earth-fault in a MV line, single-line-to-earth fault inside a HV/MV station. After having illustrated the hypotheses at the basis of the study, the circuit models for the three fault events are presented and a numerical example shows how to use them in order to check the "global safety" of the interconnected earthi…