Currently, the etiology of obesity is conceptualized as a confluence of environmental, socioeconomic, behavioral, biological and genetic factors. With regard to behavioral factors, some have suggested that a failure of self-control may contribute to the difficulty of an overweight/obese individual because of their inability to resist food or maintain physical activity. Recent research proposed that self-control could be described as similar to a muscle that can be fatigued. Thus, if an individual engages in a self-control task they have lessened ability to utilize self-control on a subsequent task. Theory also suggests self-control may be fueled by a finite resource, identified as blood glucose. The role blood glucose plays is important to understand, especially in overweight and obese populations, as they may be more likely to be insulin resistant. In effect overweight and obese individuals are less likely to adequately process glucose. Therefore overweight/obese individuals might react to self-control tasks differently than normal weight individuals. Participants who were considered normal weight, overweight, and obese were recruited from the UNT research pool. They answered questions about their trait self-control in daily life and engaged in either a task that required them to exert self-control (e.g., resist crossing out a letter unless criteria is met) or a control task (e.g., cross out a letter without restriction). All participants then engaged in a subsequent self-control task to assess if engaging in the initial self-control task reduced performance on the subsequent self-control task compared to the control task. The current research findings were not in line with previous research, in that a depletion effect in self-control was not observed; in neither the normal weight individuals nor the overweight and obese groups. There were several limitations that may have contributed to these findings including; higher DSC than observed in the general population and a possible adaptation effect due to the duration of the self-control tasks, which is in keeping with subsequently published research.

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Failure criteria play a vital role in the numerical analysis of reinforced concrete structures. The current failure criteria can be classified into two types, namely the empirical and theoretical failure criteria. Empirical failure criteria normally lack reasonable theoretical backgrounds, while theoretical ones either involve too many parameters or ignore the effects of intermediate principal stress on the concrete strength. Based on the octahedral shear stress model and the concrete tensile strength under the state of triaxial and uniaxial stress, a new failure criterion, that is, the simplified unified strength theory (UST), is developed by simplifiing the five-parameter UST for the analysis of reinforced concrete structures. According to the simplified UST failure criterion, the concrete strength is influenced by the maximum and intermediate principal shear stresses together with the corresponding normal stresses. Moreover, the effect of hydrostatic pressure on the concrete strength is also taken into account. The failure criterion involves three concrete strengths, namely the uniaxial tensile and compressive strengths and the equal biaxial compressive strength. In the numerical analysis, a degenerated shell element with the layered approach is adopted for the simulation of concrete structures. In the layered approach, concrete is divided into several layers over the thickness of the elements and reinforcing steel is smeared into the corresponding number of layers of equivalent thickness. In each concrete layer, three-dimensional stresses are calculated at the integration points. For the material modelling, concrete is treated as isotropic material until cracking occurs. Cracked concrete is treated as an orthotropic material incorporating tension stiffening and the reduction of cracked shear stiffness. Meanwhile, the smeared craclc model is employed. The bending reinforcements and the stirrups are simulated using a trilinear material model. To verify the correctness of the simplified UST failure criterion, comparisons are made with concrete triaxial empirical results as well as with the Kupfer and the Ottosen failure criteria. Finally, the proposed failure criterion is used for the flexural analysis of simply supported reinforced concrete beams. Also conducted are the punching shear analyses of single- and multi-column-slab connections and of half-scale flat plate models. In view of its accuracy and capabilities, the simplified UST failure criterion may be used to analyse beam- and slab-type reinforced concrete structures.

Ce travail est une contribution à la compréhension de la structure à courte et moyenne distance des verres à base de TeO₂ via de nouveaux verres au sein des systèmes TeO₂-TiO₂-WO₃ (TTxWy) et TeO₂-NbO₂ ̩₅-WO₃ (TNxWy). De pertinentes corrélations sont révélées entre leurs propriétés structurales (en utilisant la spectroscopie Raman) et optiques. Globalement, l’ajout de TiO₂, WO₃ ou NbO₂ ̩₅ n’engendre aucune évolution structurale brutale. L’ajout de TiO2 induit une séparation de phases entre les régions amorphes riches en TiO2 et le réseau riche en TeO2. Cette interprétation est en accord avec le comportement structural prédit par la théorie de Dietzel sur la force de champ cationique. L’ajout de WO3 entraîne l’apparition (i) d’octaèdres WO₆ uniformément dispersés à travers le réseau des ponts Te–O–Te (pour de faibles teneurs en WO₃) et (ii) de régions riches en WO3 (pour des teneurs plus importantes en WO₃). L’ajout de NbO₂ ̩₅ engendre (i) une faible dépolymérisation structurale du réseau Te–O–Te et (ii) l’apparition des régions riches en NbO₂ ̩₅. Les verres étudiés sont dotés de forts indices de réfraction linéaires (2.19 dans TTxWy et 2.13 dans TNxWy en moyenne) et de remarquables susceptibilités non linéaires χ(3) (7.03 *10-13 esu dans TTxWy et 5.48 *10-13 esu dans TNxWy en moyenne, i.e., ~47 et ~37 fois plus élevées que la valeur de χ(3) du verre SiO₂). / In this work, we present a contribution to the understanding of the short- to medium-range structure of TeO₂-based glasses via new glasses within the TeO₂-TiO₂-WO₃ (TTxWy) and TeO₂-NbO₂ ̩₅-WO₃ (TNxWy) systems. Consistent correlations are revealed between their structural (using Raman spectroscopy) and optical properties. Globally, no striking structural evolutions take place upon adding TiO₂, WO₃ or NbO₂ ̩₅. Adding TiO2 results in a phase-separation between amorphous TiO₂-rich regions and TeO2-rich network, in harmony with the predicted structural behavior on the basis of Dietzel’s cationic field strength theory. Adding WO₃ leads to (i) uniformly dispersed WO₆ octahedra throughout the Te–O–Te network (at low WO₃ contents) and (ii) amorphous WO₃-rich regions (at higher WO₃ contents). Adding NbO₂ ̩₅ engenders (i) a weak structural depolymerization of the Te–O–Te network and (ii) occurrence of NbO₂ ̩₅-rich regions. The investigated glasses exhibit high linear refractive indices (averages of 2.19 in TTxWy and 2.13 in TNxWy) and remarkable nonlinear susceptibilities χ(3) (averages of 7.03 *10-13 esu in TTxWy and 5.48 *10-13 esu in TNxWy, i.e., ~47 and ~37 times higher than χ(3) of SiO₂ glass).

Hållfasthetslära är ett viktigt och centralt område inom ingenjörsutbildningar. Men att ha grundläggande kunskap om vad som gör konstruktioner hållfasta är dock något som inte enbart bör vara förbehållet ingenjörer, utan det är även ett område som tillhör allmänbildningen. Det är av den anledningen området hållfasthet tas upp redan i grundskolans lägre åldrar i skolämnet Teknik och fördjupas successivt upp till gymnasiets tekniska program. I denna studie har fem läroböcker för ämnet Teknik för grundskolans årskurs 7-9 samt två läroböcker för kursen Teknik 1 i gymnasieskolans årskurs 1, studerats för att utreda hur området hållfasthetslära beskrivs. Metoden som används i analysen är textanalys i form av en kvantitativ innehållsanalys av förekomsten av hållfasthetsrelaterade begrepp samt en kvalitativ analys av hur begreppen beskrivs. Därtill görs en analys av hur läromedlen uppfyller styrdokumentens krav och riktlinjer. Studien visar att böckerna har stor variation i hur området hållfasthetslära framställs, dock med generaliseringar att högstadieboken beskriver området med text och gymnasieboken med formler. De studerade läroböckerna tar visserligen upp många ämnesspecifika begrepp men det är en markant skillnad mellan böckerna hur dessa begrepp beskrivs. Den fördjupade analysen som studerar om läroböckerna uppfyller styrdokumentens kursplaner i Teknik för grundskolan och Teknik 1 för gymnasieskolan påvisar även den en stor spridning mellan läroböckerna. Av studiens valda bedömningskriterier kan utläsas att området behandlas utförligt endast av två av böckerna: grundskolans Teknik Direkt (2018) från förlaget Sanoma Utbildning samt gymnasiets Teknik (2011) från förlaget Liber. Gemensamt för de valda gymnasieböckerna är att området hållfasthet behandlas mycket mer matematiskt än i högstadieböckerna och stort fokus ligger på olika former av spänningsberäkningar. Dock är det ett markant språng i abstraktionsnivå från de enklare textbaserade högstadieböckerna till gymnasieböckerna med matematiska beräkningar. Slutsatsen av detta är att varken högstadieböckerna eller gymnasieböckerna ger en heltäckande bild av viktiga grundläggande begrepp inom området hållfasthet. Studien visar att de bästa av böckerna kan i viss mån komplettera varandra, men med ogrundade val av läromedel riskerar det att bli osammanhängande. Det är därmed viktigt att läraren noggrant utvärderar lämpliga läromedel så de uppfyller det tänkta syftet i undervisningen. / Strength of materials and solid mechanics theory is an important and central area in engineering education. But having a basic knowledge of what makes structures durable, however, is not only reserved for engineers, but is also an area that belongs to general education. For this reason, the area of strength is already taken up in the elementary school's lower age in the subject of technology and is gradually expanded up to the high school's technical program. In this study, five textbooks for the subject of Technology for comprehensive school upper stage, grade 7-9, and two textbooks for the course Technology 1 in high school year 1 were studied to investigate how the field of strength theory is described. The method used in the analysis is text analysis in the form of a quantitative content analysis of the presence of strength-related concepts as well as a qualitative analysis of how the concepts are described. In addition, an analysis is made of how the teaching materials meet the requirements and guidelines of the steering documents. The study shows that the books have a great variety in how the field of strength theory is presented, however with generalizations that the upper stage textbook describes the area with text and the high school describes with formulas. Although the textbooks studied have many subject-specific concepts, it is markedly different between the books how these concepts are described. The in-depth analysis that studies whether the textbooks meet the syllabus of the steering documents in Teknik for the elementary school and Teknik 1 for the upper secondary school also shows a large distribution between the textbooks. From the chosen assessment criteria in the study, it can be seen that the area is in depth covered by only two of the books: Teknik Direkt (2018) from publisher Sanoma Utbildning (for the elementary school) and Teknik (2011) from publisher Liber (from upper secondary school). Common to all the selected high school books is that the area of strength is treated much more mathematically than for the upper stage books and great focus is placed on various forms of stress calculations. However, there is a significant leap in abstraction level from the simpler text-based upper stage books to the high school books with mathematical calculations. The conclusion of this is that neither the upper stage school books nor the high school books provide a comprehensive picture of important basic concepts in the area of strength. The study shows that the best of the books can to some extent complement each other, but with unfounded choice of study material it risks becoming incoherent. It is therefore important that the teacher carefully evaluates appropriate teaching material so that they fulfill the intended purpose of the teaching.