5,024 research outputs found
E-Learning for Teachers and Trainers : Innovative Practices, Skills and Competences
Reproduction is authorised provided the source is acknowledged.Final Published versio
The valuation of clean spread options: linking electricity, emissions and fuels
The purpose of the paper is to present a new pricing method for clean spread options, and to illustrate its main features on a set of numerical examples produced by a dedicated computer code. The novelty of the approach is embedded in the use of a structural model as opposed to reduced-form models which fail to capture properly the fundamental dependencies between the economic factors entering the production process
Benign fibrous histiocytoma of bone in a paediatric population: a report of 6 cases
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
Keeping an Eye on Wild Brown Trout (Salmo trutta) Populations: Correlation Between Temperature, Environmental Parameters, and Proliferative Kidney Disease.
Proliferative kidney disease (PKD) is an emerging disease of salmonids caused by the myxozoan parasite Tetracapsuloides bryosalmonae, which plays a major role in the decrease of wild brown trout (Salmo trutta) populations in Switzerland. Strong evidence demonstrated that water temperature modulates parasite infection. However, less knowledge exists on how seasonal water temperature fluctuations influence PKD manifestation under field conditions, how further environmental factors such as water quality may modulate the disease, and whether these factors coalesce with temperatures role possibly giving rise to cumulative effects on PKD. The aims of this study were to (1) determine the correlation between seasonal course of water temperature and PKD prevalence and intensity in wild brown trout populations, (2) assess if other factors such as water quality or ecomorphology correlate with the infection, and (3) quantitatively predict the implication of these factors on PKD prevalence with a statistical model. Young-of-the-year brown trout were sampled in 45 sites through the Canton of Vaud (Switzerland). For each site, longitudinal time series of water temperature, water quality (macroinvertebrate community index, presence of wastewater treatment plant effluent) and ecomorphological data were collected and correlated with PKD prevalence and intensity. 251 T. bryosalmonae-infected trout of 1,118 were found (overall prevalence 22.5%) at 19 of 45 study sites (42.2%). Relation between PKD infection and seasonal water temperature underlined that the mean water temperature for June and the number of days with mean temperature ≥15°C were the most significantly correlated parameters with parasite prevalence and intensity. The presence of a wastewater treatment plant effluent was significantly correlated with the prevalence and infection intensity. In contrast, macroinvertebrate diversity and river ecomorphology were shown to have little impact on disease parameters. Linear and logistic regressions highlighted quantitatively the prediction of PKD prevalence depending on environmental parameters at a given site and its possible increase due to rising temperatures. The model developed within this study could serve as a useful tool for identifying and predicting disease hot spots. These results support the importance of temperature for PKD in salmonids and provides evidence for a modulating influence of additional environmental stress factors
Empirical research on youth transitions to and within the labour market
The research project aimed to provide research outcomes on the magnitude of youth transitions, the main drivers and barriers of youth transitions and potential long-term outcomes (‘scarring’) on people’s subsequent employment trajectories. This report summarises the evidence obtained by making use of a range of individual-level data sets and methods, in particular:
• An analysis of Labour Force Survey (LFS) data creating pseudo-cohorts to examine long-term education and labour market trends affecting 16-to-24 year olds from 39 different birth cohorts and subsequent employment trajectories.
• An analysis of the ‘Ad Hoc module’ of 2009 from the European Labour Force Survey (EU:LFS) on ‘Youth Transitions’ on individual long-term outcomes of particular youth labour market transitions.
• An analysis of various cohort studies (National Child Development Study [NCDS], British Cohort Study [BCS], Youth Cohort Study [YCS], Longitudinal Study of Young People in England [LSYPE]) comparing the episodes young people experience when making transitions into the labour market in youth and early adulthood. This study uses sequential analysis for individual monthly panel data to describe biographies of young people until the age of 25 (based on BCS and NCDS) and until the age of 19 (for YCS and LSYPE).
• An analysis of the transition from secondary schooling to further destinations using a recent cohort of School Leavers National Pupil Data (NPD) merged to records of National Client Casework Information System (NCCIS) on young people’s activities after the end of compulsory education including econometric models on drivers and barriers of particular transitions
Walking Speed of Children and Adolescents With Cerebral Palsy: Laboratory Versus Daily Life.
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
A non-parametric structural hybrid modeling approach for electricity prices
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
Decreased MCM2-6 in Drosophila S2 cells does not generate significant DNA damage or cause a marked increase in sensitivity to replication interference.
A reduction in the level of some MCM proteins in human cancer cells (MCM5 in U20S cells or MCM3 in Hela cells) causes a rapid increase in the level of DNA damage under normal conditions of cell proliferation and a loss of viability when the cells are subjected to replication interference. Here we show that Drosophila S2 cells do not appear to show the same degree of sensitivity to MCM2-6 reduction. Under normal cell growth conditions a reduction of >95% in the levels of MCM3, 5, and 6 causes no significant short term alteration in the parameters of DNA replication or increase in DNA damage. MCM depleted cells challenged with HU do show a decrease in the density of replication forks compared to cells with normal levels of MCM proteins, but this produces no consistent change in the levels of DNA damage observed. In contrast a comparable reduction of MCM7 levels has marked effects on viability, replication parameters and DNA damage in the absence of HU treatment
Occupational choice of return migrants in Moldova
This paper analyzes the occupational choice of return migrants. Using the survey data on different aspects of migration in Moldova, we find that those who stayed illegally in the host country tend to go into wage employment on return to the home country. We also show that relatively better educated migrants tend not to be in formal employment (i.e., appear not to participate in the labor market), whereas those with relatively lower skills or who obtained a worse-than-expected outcome in the host country are more likely to be wage employed in the home country on return. We offer an economic analysis of these paradoxical results
Spin-wave scattering at low temperatures in manganite films
The temperature and magnetic field dependence of the resistivity
has been measured for LaSrMnO (y=0 and 0.128)
films grown on (100) SrTiO substrates. The low-temperature in the
ferromagnetic metallic region follows well with being the residual resistivity. We attribute the second and third term to
small-polaron and spin-wave scattering, respectively. Our analysis based on
these scattering mechanisms also gives the observed difference between the
metal-insulator transition temperatures of the films studied. Transport
measurements in applied magnetic field further indicate that spin-wave
scattering is a key transport mechanism at low temperatures.Comment: 5 pages, 4 figures. to appear in Phys. Rev.
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