The Role Of Individual Character Strengths In Adolescent Academic Achievement And Risky School Behavior

Adolescent achievement is a major developmental task in adolescence and reducing Risky School Behaviors is an important part of the process. Patterns of adolescent achievement and general development are the result of the cumulative process that includes a long history of experience and socialization in school, in the family, in the peer group, and in the community. This study is the first to expand understanding of these key interrelated but unique outcome variables of both Academic Achievement and risky School Behavior through examination of individual Character Strengths in the presence of other key intrapersonal and contextual variables from multiple systems in the child’s life including intrapersonal/individual and microsystem (family, peer, school) factors. Over 500 adolescents from 2 different high schools participated in the study providing information on demographics, individual Character Strengths, Adolescent Achievement Orientation, Parent Achievement Orientation, Parent Involvement, Peer Achievement Orientation, Teacher Social Support, School Attachment, Academic Achievement and Risky School Behaviors. Results revealed that the individual Character Strengths of Persistence and Prudence were significant in predicting Academic Achievement and Risky School Behaviors, respectively, when considered in comparison with other know predictors. Implications and possible application of Character Strengths to inform school-wide character education programs as well as individual character building interventions with the goal of increasing student achievement and decreasing Risky School Behaviors is discussed

A new technique to generate 100 GW-level attosecond X-ray pulses from the X-ray SASE FELs

We propose a scheme for generation of single 100 GW 300-as pulse in the X-ray free electron laser with the use of a few cycles optical pulse from Ti:sapphire laser system. Femtosecond optical pulse interacts with the electron beam in the two-period undulator resonant to 800 nm wavelength and produces energy modulation within a slice of the electron bunch. Following the energy modulator the electron beam enters the first part of the baseline gap-adjustable X-ray undulator and produces SASE radiation with 100 MW-level power. Due to energy modulation the frequency is correlated to the longitudinal position within the few-cycle-driven slice of the SASE radiation pulse. The largest frequency offset corresponds to a single-spike pulse in the time domain which is confined to one half-oscillation period near the central peak electron energy. After the first undulator the electron beam is guided through a magnetic delay which we use to position the X-ray spike with the largest frequency offset at the "fresh" part of the electron bunch. After the chicane the electron beam and the radiation produced in the first undulator enter the second undulator which is resonant with the offset frequency. In the second undulator the seed radiation at reference frequency plays no role, and only a single (300 as duration) spike grows rapidly. The final part of the undulator is a tapered section allowing to achieve maximum output power 100-150 GW in 0.15 nm wavelength range. Attosecond X-ray pulse is naturally synchronized with its fs optical pulse which reveals unique perspective for pump-probe experiments with sub-femtosecond resolution.Comment: 14 pages, 13 fig

The stability and structure of primordial reservoirs in the lower mantle: insights from models of thermochemical convection in three-dimensional spherical geometry

Large-scale chemical lateral heterogeneities are inferred in the Earth's lowermost mantle by seismological studies. We explore the model space of thermochemical convection that can maintain reservoirs of dense material for a long period of time, by using similar analysis in 3-D spherical geometry. In this study, we focus on the parameters thought to be important in controlling the stability and structure of primordial dense reservoirs in the lower mantle, including the chemical density contrast between the primordial dense material and the regular mantle material (buoyancy ratio), thermal and chemical viscosity contrasts, volume fraction of primordial dense material and the Clapeyron slope of the phase transition at 660 km depth. We find that most of the findings from the 3-D Cartesian study still apply to 3-D spherical cases after slight modifications. Varying buoyancy ratio leads to different flow patterns, from rapid upwelling to stable layering; and large thermal viscosity contrasts are required to generate long wavelength chemical structures in the lower mantle. Chemical viscosity contrasts in a reasonable range have a second-order role in modifying the stability of the dense anomalies. The volume fraction of the initial primordial dense material does not effect the results with large thermal viscosity contrasts, but has significant effects on calculations with intermediate and small thermal viscosity contrasts. The volume fraction of dense material at which the flow pattern changes from unstable to stable depends on buoyancy ratio and thermal viscosity contrast. An endothermic phase transition at 660 km depth acts as a ‘filter' allowing cold slabs to penetrate while blocking most of the dense material from penetrating to the upper mantl

Temperature and heat flux scalings for isoviscous thermal convection in spherical geometry

Parametrized convection, which has long been used to reconstruct the thermal history of planetary mantles, is based on scaling relationships between observables (including heat flux) and controlling parameters (the most important being the Rayleigh number, Ra). To explore the influence of spherical geometry on heat transfer, we have conducted two series of numerical experiments of thermal convection (one with bottom heating and the other with mixed heating) in an isoviscous spherical shell with various curvatures. Using these calculations and a generalized non-linear inversion, we then derive scaling laws for the average temperature and for the surface heat flux. In the case of bottom heating, we found that the non-dimensional average temperature is given by θm=f2/(1 +f2), where f is the ratio between the core and total radii. The non-dimensional surface heat flux is fitted well by Nutop= 0.36f0.32 Ra(0.273+0.05f)θ0.6m. This scaling indicates that the available heating power decreases with increasing curvature (decreasing f). There exist strong trade-offs between the inverted parameters, that is, different sets of parameters explain our calculations well within error bars. For mixed heating, the non-dimensional average temperature and surface heat flux are well explained by θH=θm+ (1.68 − 0.8f)[(1 +f+f2)/3]0.79 h0.79/Ra0.234, where h is the non-dimensional rate of internal heating, and Nutop= 0.59f0.05 Ra(0.300−0.003f)θ1.23H. Due to a competition between the radiogenic and convective powers, and for given values of h and Ra, there is a curvature for which the Urey ratio reaches a minimum. Applied to the Earth's mantle, the mixed heating scaling predicts a Urey ratio between 0.4 and 0.6, depending on the Rayleigh number. Additional parameters, including the thermal viscosity ratio, phase transitions, the presence of dense material in the deep mantle, and variability of the flow pattern in time, may enter an appropriate modelling of the Earth's mantle thermal histor

Influence of experimental pain on the perception of action capabilities and performance of a maximal single-leg hop

Changes in an individual's state - for example, anxiety/chronic pain - can modify the perception of action capabilities and physical task requirements. In parallel, considerable literature supports altered motor performance during both acute and chronic pain. This study aimed to determine the effect of experimental pain on perception of action capabilities and performance of a dynamic motor task. Performance estimates and actual performance of maximal single-leg hops were recorded for both legs in 13 healthy participants before, during, and after an episode of acute pain induced by a single bolus injection of hypertonic saline into vastus lateralis of 1 leg, with the side counterbalanced among participants. Both estimation of performance and actual performance were smaller (

Instrumentos financeiros para administraçao do risco cambial : uma abordagem pratica na empresa "X"

Orientador: Jose Wladimir Freitas da FonsecaMonografia(Graduaçao) - Universidade Federal do Paraná,Setor de Ciencias Sociais Aplicadas, Curso de Ciencias EconômicasResumo: Este trabalho tem como objetivo analisar como a empresa "X" se utiliza dos instrumentos financeiros para a administração do risco cambial, procurando identificar as estratégias adotadas, os instrumentos utilizados e os resultados obtidos. Para isso, procurou-se o caminho mais adequado: primeiro, na teoria dos custos de transação, que coloca o problema da organização da economia como um problema contratual, com o objetivo de estabelecimento de contratos para organizar nossas incertezas e incompletas percepções sobre a economia, e, segundo, na teoria evolucionista da firma, onde a firma é o resultado de um processo de aprendizagem ao longo do tempo, de forma que é este processo que torna possível sua progressão num ambiente de incertezas e de constantes mudanças. Através de uma breve apresentação do mercado de câmbio, verificou-se que desde a implantação do regime de câmbio flutuante em 1999 a taxa de câmbio no Brasil vem oscilando bastante. Diante dessa volatilidade e imprevisibilidade da taxa de câmbio, mais e mais empresas começaram a procurar os instrumentos financeiros, cujo objetivo é utilizar os mercados futuros de moeda para reduzir riscos dando cobertura a uma posição futura (dívida, financiamento, exportação) em aberto. Desta maneira, como os instrumentos financeiros funcionam como um instrumento de normalização, ou seja, um contrato, concluiu-se que a teoria dos custos de transação seria a mais adequada para o embasamento desse trabalho. A empresa "X", para se utilizar dos instrumentos financeiros, estabelece diretrizes e regras bem definidas, diretrizes essas que mostraram as operações de termo de moedas como o melhor instrumento financeiro a ser utilizado pela empresa. Através de análises, o que se viu foram resultados negativos superiores aos positivos. Ao que tudo indica, a empresa pode optar por não contratar os instrumentos financeiros, ficando exposta à variação cambial ou, realizar essa operações, abrindo mão, quem sabe, de um ganho futuro, mas ficando totalmente protegida contra a variação cambial

Development of compositional-gradient metallic alloys for combinatorial investigation of microstructures

International audienc

Fast colon centreline calculation using optimised 3D topological thinning

Topological thinning can be used to accurately identify the central path through a computer model of the colon generated using computed tomography colonography. The central path can subsequently be used to simplify the task of navigation within the colon model. Unfortunately standard topological thinning is an extremely inefficient process. We present an optimised version of topological thinning that significantly improves the performance of centreline calculation without compromising the accuracy of the result. This is achieved by using lookup tables to reduce the computational burden associated with the thinning process