The role of consumption in material reduction opportunities: the impact of product lifetime in supplying the UK steel demand

Most of the products purchased in the UK are manufactured in other countries. As a result, worldwide greenhouse gases (GHG) emissions released to manufacture all products purchased in the UK are significantly higher than the UK territorial emissions. More than one half of global industrial emissions result from the use of steel, cement, paper, plastics, and aluminium. In this paper, the UK consumption of products that embody these five materials is estimated. For steel, which is the most widely used among these five materials, consumption and accumulation patterns are examined across four product categories. The impact of steel product lifetime extension is examined for the UK as one option for material demand reduction at the consumption stage of the supply chain. Different levels of steel product lifetimes are simulated for the UK in 2050 and their impacts are examined in terms of UK steel production, implicit steel imports, and global carbon dioxide emissions. Steel product lifetime extension promotes a reduction in the need for steel imports, by reducing the demand for new steel, which leads to lower carbon dioxide emissions required to supply the UK steel demand. The results demonstrate the criticality of a focus on the consumption stage, since any interventions made towards demand reduction of end-use goods leads to material reduction across the supply chain

Comparaison de différents protocoles de spéciation séquentielle du phosphore dans des sédiments de rivière

Trois méthodes classiques de spéciation séquentielle du phosphore ont été appliquées aux sédiments de la rivière Sûre, à une sélection de ses affluents de taille variable, ainsi qu'aux sédiments du prébarrage Misère, un petit réservoir eutrophe situé sur la Sûre. Les protocoles comparés sont ceux de HIELTJES et LIJKLEMA (H et L), de PALUDAN et JENSEN (P et J) et de GOLTERMAN et BOOMAN (G et B).Le phosphore total des sédiments étudiés s'élève à 0,6 mg·P·g-1 séd. sec pour les petits sous-bassins expérimentaux (de l'ordre de 1 km2), à 0,8-1,0 mg·P·g-1 séd. sec pour les bassins de taille moyenne (20 à 320 km2) et à 1,8 mg·P·g-1 séd. sec pour le prébarrage Misère. Les schémas de (H et L) et de (P et J) reproduisent de façon similaire les différences qualitatives existant entre les sédiments. Toutefois les parts relatives des différentes fractions varient selon le protocole utilisé. Les rendements d'extraction obtenus avec le schéma de (G et B) sont sensiblement supérieurs aux deux autres méthodes et sont très liés aux teneurs en phosphore total des mêmes échantillons.Pour le P-labile, une bonne corrélation est obtenue entre les concentrations extraites selon les protocoles de (H et L) et (P et J) (R2 =0,84, P < 0,001) ; cependant les valeurs absolues sont 40 % supérieures pour le premier (H et L) qui utilise NH4Cl comme extractant au lieu de H2O. La fraction P- (Fe+Al) de (H et L) et la somme des fractions P-Fe et P-Al de (P et J) sont également bien corrélées (R2 =0,90, P < 0,001), mais avec des valeurs 30 % supérieures pour le second protocole (P et J) qui réalise l'extraction en deux étapes. La fraction P-Fe de (G et B) est moins bien corrélée à la fraction P-Fe de (P et J) (R2 =0,74, P < 0,01), et les résultats obtenus selon ces deux protocoles sont très éloignés en valeur absolue. Quant à la fraction P-Ca, les résultats du protocole de (G et B) ne sont ni corrélés ni similaires à ceux des deux autres schémas, en raison de la nature complètement différente des extractants appliqués.The Haute-Sûre river, with a rural watershed of 428 km2 is the principal entry of the Esch-sur-Sûre reservoir, which is mainly used for drinking-water supply. The role of particulate phosphorus (suspended matter and sediments) is important to maintain the trophic level of lakes, and in particular of reservoirs, often receiving higher external nutrient loads than natural lakes. Indeed, phosphorus flux in the Haute-Sûre basin occurs mainly in particulate form, closely linked to the hydrological and morphological conditions of its drainage basin. Several authors have shown that the fractionation of sedimentary phosphorus is strongly correlated with its bioavailability.This study was carried out in the framework of a larger project concerning the characterisation of the phosphorus from the sediments of the Sûre river watershed. The choice among the fractionation procedures described in literature and the comparison of the different results remains often difficult because of the different nature of the proposed extracting solutions, but also because of variable solid: liquid ratios, or the different exposure times proposed. Three traditional fractionation methods, HIELTJES and LIJKLEMA (H and L) (1980), PALUDAN and JENSEN (P and J) (1995) and GOLTERMAN and BOOMAN (G and B) (1988), were thus tested in the present study and applied to sediments from the Sûre river bed and a selection of its tributaries of variable size as well as to the Misère predam sediments, a small reservoir located upstream from the main reservoir.The first protocol (H and L) classes the sedimentary phosphorus in four fractions: labile-P obtained with a NO4C1 1M solution, (Fe+Al)-P with NaOH 0.1M as reagent, Ca-P with a HCl 0.5 M solution and residual-P obtained by difference of the three precedent fractions with total P. The second (P and J) separates sedimentary phosphorus in 6 fractions: labile-P extracted with H2O, Fe-P with a dithionite-bicarbonate solution (NaHCO3 0.11 M and Na2 S2 O4 0.11 M), Al-P with a NaOH 0.1 M solution after acidification of the supernatant to pH=1 and separation of the resultant precipitate, AH-P (humic acids - P) obtained after mineralisation (H2 SO4 /K2 SO4 sat. at 400°C) of the previous precipitate, Ca-P with a HCl 0.5 M solution, and finally residual-P after drying and mineralisation of the sediment having undergone all the previous steps (H2 SO4 /K2 SO4 sat. at 400°C). The third tested protocol (G and B) proposes chelates as extracting solutions: the fraction Fe-P with Ca-NTA/dithionite (CaCO3 0.04 M + NTA 0.02 M - Na2 S2 O4 0.045 M), and the Ca-P fraction with Na-EDTA 0.05 M at pH=8.The obtained results demonstrate a substantial difference between the sampled sediments. The total phosphorus content of the sampled sediments varied between 0.6 mg·P·g-1 dw for the small experimental basins (around 1 km2), 0.8 to 1.0 mg·P·g-1 dw for the medium-sized basins (20 to 320 km2) and 1.8 mg·P·g-1 dw for the Misère predam (lentic system). As regards the phosphorus fractionation, the (H and L) and the (P and J) procedures are concordant from the qualitative point of view, the relative importance of the different fractions varying nevertheless according to the used scheme. With the (G and B) method the extracted P fractions were highest. In relative terms (% P-fraction in relation to total-P), the sampled sediments have a very similar behaviour according to (G and B), the quantitative differences between samples being strongly correlated to their total phosphorus content.A good correlation was found between the labile-P fractions determined according to (H and L) and according to (P and J) (R2=0.84, P < 0.001) with however 40% higher values for (H and L). The P-(Fe+Al) fraction of (H and L) and the sum of the fractions P-Fe + P-Al of (P and J) are correlated as well (R2=0.90, P < 0.001) with 30% higher values for (P and J). Regarding the P-Fe fraction, the results obtained with the (G and B) and (P and J) protocols are correlated (R2=0.74, P < 0.01), but results are quantitatively quite different. The P-Ca fraction of the (G and B) protocol is badly correlated and very different from the two other procedures, because of the completely different nature of the extracting solutions

A Mixed Real and Floating-Point Solver

Reasoning about mixed real and floating-point constraints is essential for developing accurate analysis tools for floating-point pro- grams. This paper presents FPRoCK, a prototype tool for solving mixed real and floating-point formulas. FPRoCK transforms a mixed formula into an equisatisfiable one over the reals. This formula is then solved using an off-the-shelf SMT solver. FPRoCK is also integrated with the PRECiSA static analyzer, which computes a sound estimation of the round-off error of a floating-point program. It is used to detect infeasible computational paths, thereby improving the accuracy of PRECiSA

Social perception drives eye-movement related brain activity: evidence from pro- and anti-saccades to faces

Social stimuli such as faces attract and retain attention to a greater extent than other objects. Using fMRI, we investigated how the activity of oculomotor and visual brain regions is modulated when participants look towards or away from visual stimuli belonging to different categories (faces and cars). We identified a region within the superior frontal sulcus showing greater difference between anti- and pro-saccades to faces than to cars, and thereby supporting inhibitory control in a social context. In contrast, ventral occipito-temporal regions and the amygdala, which are associated with face perception, showed higher activity for pro-saccades than anti-saccades for faces, but the reverse for cars, suggesting that contextual, top-down mechanisms modulate the functional specialisation of areas involved in perception. In addition, during saccades in the presence of faces, we found increased functional connectivity between the frontal eye-fields and other cortical and subcortical oculomotor structures, namely the inferior frontal eye field, the posterior parietal cortex and the basal ganglia, possibly reflecting the higher demand put on the oculomotor system to inhibit responses to socially salient stimuli. For the first time, these data highlight neural bases for the different orienting responses towards or away from faces as compared to other objects

Mixed Land Use as an Intrinsic Feature of Sprawl: A Short-Term Analysis of Settlement Growth and Population Distribution Using European Urban Atlas

This study investigates the land-use/population mix over time as the base to derive an indicator of urban sprawl. Land-use individual patches (provided by Urban Atlas, hereafter UA, with a detailed spatial geometry at 1:10,000 scale) were associated with the total (resident) population based on official statistics (census enumeration districts and other public data sources), providing a comprehensive mapping of the spatial distribution of population density by land-use class in a representative case study for the Mediterranean region (metropolitan Athens, Greece). Data analysis adopted a mix of statistical techniques, such as descriptive statistics, non-parametric curve interpolation (smoothing splines), and exploratory multivariate statistics, namely hierarchical clustering, non-metric multi-dimensional scaling and confirmative factor analysis. The results of this study indicate a non-linear gradient of density decline from downtown (dominated by compact settlements) to peripheral locations (dominated by natural land). Population density in agricultural land was locally high and increasing over time; this result suggests how mixed land use may be the base of intense sprawl in large metropolitan regions. The methodology implemented in this study can be generalized over the whole sample of European cities included in Urban Atlas, providing a semi-automatic assessment of exurban development and population re-distribution over larger metropolitan regions

Appropriate end points for the characterization of behavioral changes in developmental toxicology.

The present paper is devoted to second- and higher-tier test methods for the characterization of behavioral changes produced in rodents by exposure to noxious agents during development. The paper analyzes a series of end points that are informative about specific processes and underlying regulatory mechanisms but require greater technical sophistication and larger investments than first-tier end points. This applies to ultrasonic emissions in successive postnatal periods; to mother-pup interactions, including appropriate cross-fostering controls; to social (including sexual) interaction tests from the infantile to the young adult stage; and to a variety of conditioning and learning tests using both positive and negative reinforcement

Agro-forest management and soil degradation in Mediterranean environments. Towards a strategy for sustainable land use in vineyard and Olive Cropland

Landscape fragmentation typical of the Mediterranean region is the result of long-term settlement history and continuous socioeconomic interactions among countries. In complex agro-ecosystems of the Mediterranean basin, formulation of practical guidelines aimed at counteract soil and land degradation, water depletion, rural area depopulation, and the loss of agricultural knowledge is imperative. Based on a multidisciplinary, integrated approach, the present contribution discusses the role of traditional agricultural systems in ecosystem services provision, considering together economic sustainability and the medium-term ecological benefits. A permanent monitoring of rural areas specialized in traditional crop production such as olive and vine may support optimal selection of cultivars finely adapted to a warm climate. A competitive agricultural system may consider human well-being, social equity, and conservation of natural resources, to ensure a high level of services for current and future generations. Recovery and conservation of agricultural resources provide positive externalities and social benefits at both local and regional levels. Understanding the multiple use and functions of tree crop landscapes will contribute to improve food security, land quality, and the provision of related ecosystem services

Population dynamics and agglomeration factors: A non-linear threshold estimation of density effects

Abstract: Although Southern Europe is relatively homogeneous in terms of settlement characteristics and urban dynamics, spatial heterogeneity in its population distribution is still high, and differences across regions outline specific demographic patterns that require in-depth investigation. In such contexts, density-dependent mechanisms of population growth are a key factor regulating socio-demographic dynamics at various spatial levels. Results of a spatio-temporal analysis of the distribution of the resident population in Greece contributes to identifying latent (density-dependent) processes of metropolitan growth over a sufficiently long time interval (1961-2011). Identification of density-dependent patterns of population growth contributes to the analysis of socioeconomic factors underlying demographic divides, possibly distinguishing between the effects of population concentration and dispersion. Population growth rates were non-linearly correlated with population density, highlighting a positive (or negative) impact of urban concentration on demographic growth when population is lower (or higher) than a fixed threshold (2800 and 1300 inhabitants/km2 in 1961 and 2011, respectively). In a context of low population density (less than 20 inhabitants/km2), the relationship between density and growth was again negative, contrasting with the positive and linear relationship observed in denser contexts. This result evidences a sort of 'depopulation' trap that leads to accelerated population decline under a defined density threshold. An improved understanding of density-dependent mechanisms of population growth and decline contributes to rethinking strategies of sustainable development and social policies more adapted to heterogeneous regional contexts