Yoga, Physical Education, and Self-Esteem: Off the Court and Onto the Mat for Mental Health

Researchers studied increases in self-esteem of eighth-grade students after participation in regular physical education and yoga-enhanced physical education classes. Self-esteem was measured by the Coopersmith Self-Esteem Inventory. The Coopersmith Self-Esteem Inventory was given pre, mid, and post test in both the experimental and control group. The results showed that over the course of the eightweek intervention, self-esteem did increase in both the experimental and control groups. There was no significant difference in self-esteem between regular physical education activities and yoga. The study revealed the importance of physical activity, including yoga, for enhancing self-esteem. Theories for why self-esteem increased over time are discussed in the study

Mechanical behavior and durability of fibre reinforced mortar in an aggressive environment

International audienceThis study was carried out to examine the mechanical behavior and durability of mortar with or without addition of silica fume, with and without steel fibre reinforcement. Three tests were carried out: strength, depth of pH reduction and micro-structural analysis by SEM. The mixes studied had two water cement ratios (0.5; 0.65); with a 0.5% steel fibre content and 10% silica fume content (in substitution of cement). To characterize the durability performance of the mortars studied, samples were exposed to one-year in three environments: wet environment (control samples under laboratory conditions, 20°C and 95% RH) and exposure samples: in cyclic environment (wetting and drying) and a sewage pumping station sump (an aggressive environment). SEM observations were carried out on samples to study the micro structural changes in the mortar's matrix. One sees the organic matter deposits located inside a pore and one can see the formation of the secondary ettringite. It is concluded that the compressive strength of the samples are relatively unaffected by mix type and environment. The samples exposed to sewage exhibited evidence a depth of pH reduction

Conditional Preference Nets and Possibilistic Logic

International audienceCP-nets (Conditional preference networks) are a well-known compact graphical representation of preferences in Artificial Intelligence, that can be viewed as a qualitative counterpart to Bayesian nets. In case of binary attributes it captures specific partial orderings over Boolean interpretations where strict preference statements are defined between interpretations which differ by a single flip of an attribute value. It respects preferential independence encoded by the ceteris paribus property. The popularity of this approach has motivated some comparison with other preference representation setting such as possibilistic logic. In this paper, we focus our discussion on the possibilistic representation of CP-nets, and the question whether it is possible to capture the CP-net partial order over interpretations by means of a possibilistic knowledge base and a suitable semantics. We show that several results in the literature on the alleged faithful representation of CP-nets by possibilistic bases are questionable. To this aim we discuss some canonical examples of CP-net topologies where the considered possibilistic approach fails to exactly capture the partial order induced by CP-nets, thus shedding light on the difficulties encountered when trying to reconcile the two frameworks

Modeling and influence of shear retention parameter on the response of reinforced concrete structural elements

To obtain the complete solutions describing the balance of a reinforced concrete structure, it is necessary to introduce a behavioral law characterizing the physical properties of material. The goal of this work is to study the response of reinforced concrete elements by taking into account the variation of the shear retention parameter (aggregate interlock) and the mesh density. The concrete was assumed as elastic-plastic material and follow Drucker-Prager failure criterion with associated flow rule, the steel reinforcements were assumed to be elastic-perfectly plastic. The numerical results obtained are compared with other results available in the literature.Для отримання повних розв’язків із метою опису рівноваги залізобетонної конструкції необхідно використати рівняння, що характеризують фізичні властивості матеріалів. Вивчалася поведінка залізобетонних елементів з урахуванням зміни ретенційного параметра зсуву (множинного блокування) і щільності сітки. Постулювалось, що бетон являє собою пружно-пластичний матеріал, для якого правдиві критерій руйнування Друкера-Прагера та закон асоційованої течії, в той час як стальні елементи арматури припускалися пружно-ідеально-пластичними. Отримані результати числових розрахунків порівнювалися з наведеними у літературних джерелах.Для получения полных решений с целью описания равновесия железобетонной конструкции необходимо использовать уравнения, характеризующие физические свойства материала. Изучено поведение железобетонных элементов с учетом изменения ретенционного параметра сдвига (множественной блокировки) и плотности сетки. Постулировалось, что бетон является упругопластическим материалом, для которого справедливы критерий разрушения Друкера-Прагера и закон ассоциированного течения, тогда как стальные элементы арматуры предполагались упруго-идеально-пластичными. Полученные результаты численных расчетов сравнивались с приведенными в литературных источниках

The Compressive Strength of High-Performance Concrete and Ultrahigh-Performance

The compressive strength of silica fume concretes was investigated at low water-cementitious materials ratios with a naphthalene sulphonate superplasticizer. The results show that partial cement replacement up to 20% produce, higher compressive strengths than control concretes, nevertheless the strength gain is less than 15%. In this paper we propose a model to evaluate the compressive strength of silica fume concrete at any time. The model is related to the water-cementitious materials and silica-cement ratios. Taking into account the author's and other researchers’ experimental data, the accuracy of the proposed model is better than 5%

Intercropping Promotes the Ability of Legume and Cereal to Facilitate Phosphorus and Nitrogen Acquisition through Root- Induced Processes

Intercropping of cereal and legume can improve the use of resources for crop growth compared to cropping system. An increase in soil phosphorus (P) and nitrogen (N) acquisition by root-induced biochemical changes of intercropped species has been reported as key processes of facilitation and complementarily between both intercropping legumes and cereals. Indeed, the functional facilitation prevails over interspecific competition under nutrients limiting for crop growth. Results showed that P availability significantly increased in the rhizosphere of both species, especially in intercropping under the P-deficient soil conditions. This increase was associated with high efficiency efficiency in use of rhizobial, plant growth and resource use efficiency as indicated by higher land equivalent ratio (LER) and N nutrition index. In addition, the rhizosphere P availability and nodule biomass were positively correlated (r2 = 0.71**, and r2 = 0.62**) in the intercropped common bean grown at P-deficient soil. The increased P availability presumably improved biomass and yield in intercropping, although it mainly enhanced intercropped maize grain yield. Exploiting belowground parameters in a legume-cereal intercropping is likely necessary to maximize rhizosphere-interspecific interactions as a strategy to improve the symbiotic rhizobial efficiency and microbial activities, as a result of root-induced pH and N availability changes under low P soils

Using Comparative Preference Statements in Hypervolume-Based Interactive Multiobjective Optimization

International audienceThe objective functions in multiobjective optimization problems are often non-linear, noisy, or not available in a closed form and evolutionary multiobjective optimization (EMO) algorithms have been shown to be well applicable in this case. Here, our objective is to facilitate interactive decision making by saving function evaluations outside the "interesting" regions of the search space within a hypervolume-based EMO algorithm. We focus on a basic model where the Decision Maker (DM) is always asked to pick the most desirable solution among a set. In addition to the scenario where this solution is chosen directly, we present the alternative to specify preferences via a set of so-called comparative preference statements. Examples on standard test problems show the working principles, the competitiveness, and the drawbacks of the proposed algorithm in comparison with the recent iTDEA algorithm

An Axiomatic Approach to Support in Argumentation

International audienceIn the context of bipolar argumentation (argumentation with two kinds of interaction, attacks and supports), we present an axiomatic approach for taking into account a special interpretation of the support relation, the necessary support. We propose constraints that should be imposed to a bipolar argumentation system using this interpretation. Some of these constraints concern the new attack relations, others concern acceptability. We extend basic Dung’s framework in different ways in order to propose frameworks suitable for encoding these constraints. By the way, we propose a formal study of properties of necessary support