5,766 research outputs found

    An Ecotechnical Alternative: An Embankment of Incinerated Municipal Solid Waste

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    Incineration seems to be one of the best solutions to solve the problem of household refuse disposal. In compliance with European legislation, part of this incinerated refuse, could be used in public works. The authorities are fully aware of the high economic stakes involved, and this is the reason why they would like to control and define the conditions of use of such incinerated refuse. An innovative alternative is presented in this paper, involving the use of slag from Municipal Solid Waste Incineration (I.M.S.W.R.), lightened by the inclusion of old tyres, and strengthened with a layer of geosynthetics, in order to build a retaining wall for a road embankment. With the possibility of seeding the wall facing, the structure can be blended harmoniously into the site. This reinforced structure was monitored in order to check its behavior, especially its thermal behavior

    Benign fibrous histiocytoma of bone in a paediatric population: a report of 6 cases

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    Case records and radiological investigations of six children with benign fibrous histiocytoma were studied retrospectively. BFH occurred in the femur (n=2), tibia (n=2) and fibula (n=2). Clinically, patients reported pain from the lesion lasting several months (mean 6months). The pain was not associated with pathological fracture in any patient. On X-rays, the lesions appeared as lytic and sharply demarcated with a sclerotic rim and fine trabeculations. The reported cases were located in the metaphysis and the diaphysis of the long bones. The tumour was restricted to bone, without periosteal or soft tissue reaction. Treatment consisted of careful intralesional curettage of the lesion; the defect was thereafter filled with bone bank graft or injectable phosphocalcic cement. The length of follow-up ranged from 24months to 4.75years (mean 35.2months). One case presented with recurrence of the disease and required successful repeat intralesional curettage. Benign fibrous histiocytoma is probably underestimated among patients less than 20years of age. This diagnosis should be considered in any child or teenager who presents with a non-ossifying fibroma accompanied by unexplainable pain or a rapid growing. Surgery restricted to the osteolytic lesion seems sufficient to achieve bone healin

    Grassland Management and Animal Product Quality

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    The expectations of consumers ultimately determine the specification of product quality; and grassland systems produce a wide range of animal-based products. Therefore, to provide focus, this paper deals only with food products that are destined for markets that exhibit strong discretionary choice. Quality expectations of consumers have traditionally been based on product attributes such as taste, freshness, nutritional value and appearance, but customer expectations are expanding to encompass food safety, environmental care, animal welfare and biotechnologies. Grassland forages and their management influence the intrinsic sensory properties of food. A dairy products case study is presented, indicating that pasture species and their interaction with local environmental factors, and the methods of forage conservation, can influence the chemical composition of milk, its ability to be processed into butter or cheese, and the final sensory characteristics of the product. These effects may result directly from compounds originating in the forage (e.g. carotenoids, aromatic terpenes) or indirectly through forage-related changes in animal physiology and enzyme production. Knowledge of these influences and the strict control of the determining factors are key elements in the granting of Protected Denomination of Origin (DMO) status and the benefits that accrue from marketing strategies that depend on this status. Animal feeding regimes also influence the attributes of meat. Pasture-grazed animals have harder and yellower carcass fat than grain-fed animals. The daily energy intake of pasture-grazed animals is also generally lower; therefore there is less intra-muscular marbling. In addition, glycogen levels tend to be more marginal, which can negatively interact with psychological stress to produce a greater incidence of high ultimate pH carcasses. High pH levels (\u3e 5.8) result in reduced tenderness, dark muscle and reduced shelf-life of fresh and chilled meats. Early identification of product quality variation is key to placing meat into the correct supply chain, and maximising the total value of the carcass. The positive and negative aspects of fatty acid profiles, phenol and indole compounds, and antioxidants originating from forages are discussed in respect of meat flavour and animal health. Tight planning and management protocols for both plants and animals are crucial to achieving quality raw material from grassland systems. Unlike feedlot and barn-based enterprises, variation in forage quantity and quality can severely impact on animal performance, timeliness of supply and raw product constituents. Control of a forage-based system requires the setting of performance targets and on-going monitoring. Such measures can signal when the tactical use of specialist forages, or of high-quality supplements, will be of most value in maintaining target performance and animal health. Consistently supplying products with desired attributes, attending to animal welfare expectations and caring for environmental integrity will all be required if the credibility of ‘natural’ grassland products is to be sustained in the market-place. Controlled grazing of animals will be invaluable in meeting these multiple market demands

    Insights into mixed contaminants interactions and its implication for heavy metals and metalloids mobility, bioavailability and risk assessment

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    Mobility of heavy metals at contaminated sites is mainly influenced by the soil physicochemical properties and environmental conditions, therefore assessing heavy metals (HMs) and metalloids fractionation can provide insights into their potential risk and the mechanisms that regulate bioavailability. A 12-months mesocosms experiment was setup to investigate the effect of physicochemical factors (pH, moisture, and temperature) and weathering (time) on HMs and metalloids fractionation in three different multi-contaminated soil matrices (low, medium, and high contamination) collected from a soil treatment facility located in the United Kingdom, and two rural contaminated soil samples. The study demonstrates that even though Pb and Zn were found associated with the exchangeable fraction in the soil with the highest contamination (total average Pb 3400 mg/kg, and total average Zn 2100 mg/kg in Soil C), neither the condition applied nor the weathering caused an increase in their mobility. Although it was expected that lower pH (4.5) would favours the dissociation of HMs and metalloids, no significant differences were observed, potentially due to the initial alkaline pH of the genuine-contaminated soil samples. The results show that even though total concentration of Pb, Cu, and Zn exceed the soil standards and guideline values, HMs were predominantly associated with the non-exchangeable fraction, while only 5% were dissolved in the pore water fraction (potentially bioavailable). In addition, the mobility and bioavailability of HMs remained constant over the 12 months monitoring, suggesting that these soils pose negligible risk to the environment

    A non-parametric structural hybrid modeling approach for electricity prices

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    We develop a stochastic model of zonal/regional electricity prices, designed to reflect information in fuel forward curves and aggregated capacity and load as well as zonal or regional price spreads. We use a nonparametric model of the supply stack that captures heat rates and fuel prices for all generators in the market operator territory, combined with an adjustment term to approximate congestion and other zone-specific behavior. The approach requires minimal calibration effort, is readily adaptable to changing market conditions and regulations, and retains sufficient tractability for the purpose of forward price calibration. The model is illustrated for the spot and forward electricity prices of the PS zone in the PJM market, and the set of time-dependent risk premiums are inferred and analyzed

    SENSE: A comparison of photon detection efficiency and optical crosstalk of various SiPM devices

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    This paper describes a comparison of photon detection efficiency and optical crosstalk measurements performed by three partners: Geneva University, Catania Observatory and Nagoya University. The measurements were compared for three different SiPM devices with different active areas: from 9 mm2mm^2 up to 93.6 mm2mm^2 produced by Hamamatsu. The objective of this work is to establish the measurements and analysis procedures for calculating the main SiPM parameters and their precision. This work was done in the scope of SENSE project which aims to build roadmap for the last developments in field of sensors for low light level detection

    Time series prediction via aggregation : an oracle bound including numerical cost

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    We address the problem of forecasting a time series meeting the Causal Bernoulli Shift model, using a parametric set of predictors. The aggregation technique provides a predictor with well established and quite satisfying theoretical properties expressed by an oracle inequality for the prediction risk. The numerical computation of the aggregated predictor usually relies on a Markov chain Monte Carlo method whose convergence should be evaluated. In particular, it is crucial to bound the number of simulations needed to achieve a numerical precision of the same order as the prediction risk. In this direction we present a fairly general result which can be seen as an oracle inequality including the numerical cost of the predictor computation. The numerical cost appears by letting the oracle inequality depend on the number of simulations required in the Monte Carlo approximation. Some numerical experiments are then carried out to support our findings

    Walking Speed of Children and Adolescents With Cerebral Palsy: Laboratory Versus Daily Life.

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    The purpose of this pilot study was to compare walking speed, an important component of gait, in the laboratory and daily life, in young individuals with cerebral palsy (CP) and with typical development (TD), and to quantify to what extent gait observed in clinical settings compares to gait in real life. Fifteen children, adolescents and young adults with CP (6 GMFCS I, 2 GMFCS II, and 7 GMFCS III) and 14 with TD were included. They wore 4 synchronized inertial sensors on their shanks and thighs while walking at their spontaneous self-selected speed in the laboratory, and then during 2 week-days and 1 weekend day in their daily environment. Walking speed was computed from shank angular velocity signals using a validated algorithm. The median of the speed distributions in the laboratory and daily life were compared at the group and individual levels using Wilcoxon tests and Spearman's correlation coefficients. The corresponding percentile of daily life speed equivalent to the speed in the laboratory was computed and observed at the group level. Daily-life walking speed was significantly lower compared to the laboratory for the CP group (0.91 [0.58-1.23] m/s vs 1.07 [0.73-1.28] m/s, p = 0.015), but not for TD (1.29 [1.24-1.40] m/s vs 1.29 [1.20-1.40] m/s, p = 0.715). Median speeds correlated highly in CP (p < 0.001, rho = 0.89), but not in TD. In children with CP, 60% of the daily life walking activity was at a slower speed than in-laboratory (corresponding percentile = 60). On the contrary, almost 60% of the daily life activity of TD was at a faster speed than in-laboratory (corresponding percentile = 42.5). Nevertheless, highly heterogeneous behaviors were observed within both populations and within subgroups of GMFCS level. At the group level, children with CP tend to under-perform during natural walking as compared to walking in a clinical environment. The heterogeneous behaviors at the individual level indicate that real-life gait performance cannot be directly inferred from in-laboratory capacity. This emphasizes the importance of completing clinical gait analysis with data from daily life, to better understand the overall function of children with CP
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