990 resultados para Universality class
Resumo:
Cytokines are proteins that provide essential signals to blood and immune cells. The evolution of this system was determined from primitive organisms to humans and zebrafish. Analysis of zebrafish granulocyte colony-stimulating factor (GCSF) signalling revealed broad conservation of function with mammals and a novel role in white blood cell migration.
Resumo:
Choline dihydrogen phosphate ([N1.1.1.2OH]DHP) and 1-butyl-3-methylimidazolium dihydrogen phosphate ([C4mim]DHP) were synthesized as a new class of proton-conducting ionic plastic crystals. Both [N1.1.1.2OH]DHP and [C4mim]DHP showed solid–solid phase transition(s) and showed a final entropy of fusion lower than 20 J K−1 mol−1 which is consistent with Timmerman’s criterion for molecular plastic crystals. The ionic conductivity of [N1.1.1.2OH]DHP was in the range of 10−6 S cm−1–10−3 S cm−1 in the plastic crystalline phase. On the other hand, the ionic conductivity of [C4mim]DHP showed about 10−5 S cm−1 in the plastic crystalline phase. [N1.1.1.2OH]DHP showed one order of magnitude higher ionic conductivity than [C4mim]DHP in the temperature range where the plastic phase is stable.
Resumo:
In this article, I analyze a class of contest success functions (CSFs) that satisfy Luce's Choice Axiom. I show that the functional forms of these CSFs can be fully identified if they are characterized by a partial differential equation (PDE), which has several intuitive economic interpretations. This POE approach provides foundations for popular CSFs and their generalizations.
Resumo:
This thesis explores the multi-dimensional nature of class size and how educational processes are shaped by different class size environments in four undergraduate business courses. Class size significantly influenced how curricula were structured and designed for learning and consequently students' course expectations and learning experiences in large and small classes.
Resumo:
The thesis investigates various machine learning approaches to reducing data dimensionality, and studies the impact of asymmetric data on learning in image retrieval. Efficient algorithms are proposed to reduce the data dimensionality. Integration strategies for one-class classification are designed to address asymmetric data issue and improve retrieval effectiveness.
Resumo:
Background
School recess provides a daily opportunity for children to engage in physically active behaviours. However, few studies have investigated what factors may influence children's physical activity levels in this context. Such information may be important in the development and implementation of recess interventions. The aim of this study was to investigate the association between a range of recess variables and children's sedentary, moderate and vigorous physical activity in this context.
Methods
One hundred and twenty-eight children (39% boys) aged 9-10 years old from 8 elementary schools had their physical activity levels observed during school recess using the System for Observing Children's Activity and Relationships during Play (SOCARP). Playground variables data were also collected at this time. Multilevel prediction models identified variables that were significantly associated with children's sedentary, moderate and vigorous physical activity during recess.
Results
Girls engaged in 13.8% more sedentary activity and 8.2% less vigorous activity than boys during recess. Children with no equipment provision during recess engaged in more sedentary activity and less moderate activity than children provided with equipment. In addition, as play space per child increased, sedentary activity decreased and vigorous activity increased. Temperature was a significant negatively associated with vigorous activity.
Conclusions
Modifiable and unmodifiable factors were associated with children's sedentary, moderate and vigorous physical activity during recess. Providing portable equipment and specifying areas for activities that dominate the elementary school playground during recess may be two approaches to increase recess physical activity levels, though further research is needed to evaluate the short and long-term impact of such strategies.
Resumo:
Understanding children’s physical activity (PA) patterns and the factors that may influence PA are important for developing interventions within this population. One hundred and ten children aged 9–0 years from 8 schools had their PA patterns assessed over 7 days. Physiological and self-report data were also collected. Multilevel analyses revealed that cardiorespiratory fitness was a consistent, significant and positive predictor of weekday and weekend PA, while the availability of home sedentary activities was a significant but negative predictor of PA. Since a range of variables were associated with PA levels, intervention developers should be cognizant of variables that may influence children’s activity
Resumo:
This paper poses and solves a new problem of consensus control where the task is to make the fixed-topology multi-agent network, with each agent described by an uncertain nonlinear system in chained form, to reach consensus in a fast finite time. Our development starts with a set of new sliding mode surfaces. It is proven that, on these sliding mode surfaces, consensus can be achieved if the communication graph has the proposed directed spanning tree. Next, we introduce the multi-surface sliding mode control to drive the sliding variables to the sliding mode surfaces in a fast finite time. The control Lyapunov function for fast finite time stability, motivated by the fast terminal sliding mode control, is used to prove the reachability of the sliding mode surface. A recursive design procedure is provided, which guarantees the boundedness of the control input.