868 resultados para AI behaviour


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BACKGROUND: Endurance athletes are advised to optimize nutrition prior to races. Little is known about actual athletes' beliefs, knowledge and nutritional behaviour. We monitored nutritional behaviour of amateur ski-mountaineering athletes during 4 days prior to a major competition to compare it with official recommendations and with the athletes' beliefs. METHODS: Participants to the two routes of the 'Patrouille des Glaciers' were recruited (A, 26 km, ascent 1881 m, descent 2341 m, max altitude 3160 m; Z, 53 km, ascent 3994 m, descent 4090 m, max altitude 3650 m). Dietary intake diaries of 40 athletes (21 A, 19 Z) were analysed for energy, carbohydrate, fat, protein and liquid; ten were interviewed about their pre-race nutritional beliefs and behaviour. RESULTS: Despite belief that pre-race carbohydrate, energy and fluid intake should be increased, energy consumption was 2416 ± 696 (mean ± SD) kcal · day(-1), 83 ± 17 % of recommended intake, carbohydrate intake was only 46 ± 13 % of minimal recommended (10 g · kg(-1) · day(-1)) and fluid intake only 2.7 ± 1.0 l · day(-1). CONCLUSIONS: Our sample of endurance athletes did not comply with pre-race nutritional recommendations despite elementary knowledge and belief to be compliant. In these athletes a clear and reflective nutritional strategy was lacking. This suggests a potential for improving knowledge and compliance with recommendations. Alternatively, some recommendations may be unrealistic.

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OBJECTIVE: We evaluated whether regional differences in physical activity (PA) and sedentary behaviour (SB) existed along language boundaries within Switzerland and whether potential differences would be explained by socio-demographics or environmental characteristics. METHODS: We combined data of 611 children aged 4 to 7 years from four regional studies. PA and SB were assessed by accelerometers. Information about the socio-demographic background was obtained by questionnaires. Objective neighbourhood attributes could be linked to home addresses. Multivariate regression models were used to test associations between PA and SB and socio-demographic characteristics and neighbourhood attributes. RESULTS: Children from the German compared to the French-speaking region were more physically active and less sedentary (by 10-15 %, p < 0.01). Although German-speaking children lived in a more favourable environment and a higher socioeconomic neighbourhood (differences p < 0.001), these characteristics did not explain the differences in PA behaviour between French and German speaking. CONCLUSIONS: Factors related to the language region, which might be culturally rooted were among the strongest correlates of PA and SB among Swiss children, independent of individual, social and environmental factors.

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The six most important cost-effective policies on tobacco control can be measured by the Tobacco Control Scale (TCS). The objective of our study was to describe the correlation between the TCS and smoking prevalence, self-reported exposure to secondhand smoke (SHS) and attitudes towards smoking restrictions in the 27 countries of the European Union (EU27).

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Past studies on the personnel selection demonstrated that a supervisor's advice to discriminate can lead to compliant behaviours. This study had the aim to extend past findings by examining what can overcome the powerful influence of the hierarchy. 50 Swiss managers participated to an in-basket exercise. The main task was to evaluate Swiss candidates (in-group) and foreigners (out-groups: Spanish and Kosovo Albanians) and to select two applicants for a job interview. Main results were the effect of codes of conduct to prevent discrimination against out-group applicants in the presence of a supervisor's advice to prefer in-group members. But, when participants were accountable to an audience, this beneficial effect disappears because participants followed the supervisor's advice. The second aim was to assess if the difference in responses between participants was related to their difference in moral attentiveness. Results showed some significant relationships but not always in the direction expected.

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The strength properties of paper coating layer are very important in converting and printing operations. Too great or low strength of the coating can affect several problems in printing. One of the problems caused by the strength of coating is the cracking at the fold. After printing the paper is folded to final form and the pages are stapled together. In folding the paper coating can crack causing aesthetic damage over printed image or in the worst case the centre sheet can fall off in stapling. When folding the paper other side undergoes tensile stresses and the other side compressive stresses. If the difference between these stresses is too high, the coating can crack on the folding. To better predict and prevent cracking at the fold it is good to know the strength properties of coating layer. It has measured earlier the tensile strength of coating layer but not the compressive strength. In this study it was tried to find some way to measure the compressive strength of the coating layer and investigate how different coatings behave in compression. It was used the short span crush test, which is used to measure the in-plane compressive strength of paperboards, to measure the compressive strength of the coating layer. In this method the free span of the specimen is very small which prevent buckling. It was measured the compressive strength of free coating films as well as coated paper. It was also measured the tensile strength and the Bendtsen air permeance of the coating film. The results showed that the shape of pigment has a great effect to the strength of coating. Platy pigment gave much better strength than round or needle-like pigment. On the other hand calcined kaolin, which is also platy but the particles are aggregated, decreased the strength substantially. The difference in the strength can be explained with packing of the particles which is affecting to the porosity and thus to the strength. The platy kaolin packs up much better than others and creates less porous structure. The results also showed that the binder properties have a great effect to the compressive strength of coating layer. The amount of latex and the glass transition temperature, Tg, affect to the strength. As the amount of latex is increasing, the strength of coating is increasing also. Larger amount of latex is binding the pigment particles better together and decreasing the porosity. Compressive strength was increasing when the Tg was increasing because the hard latex gives a stiffer and less elastic film than soft latex.

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Bioactive glasses are surface-active ceramic materials which support and accelerate bone growth in the body. During the healing of a bone fracture or a large bone defect, fixation is often needed. The aim of this thesis was to determine the dissolution behaviour and biocompatibility of a composite consisting of poly(ε-caprolactone-co-DL-lactide) and bioactive glass (S53P4). In addition the applicability as an injectable material straight to a bone defect was assessed. In in vitro tests the dissolution behaviour of plain copolymer and composites containing bioactive glass granules was evaluated, as well as surface reactivity and the material’s capability to form apatite in simulated body fluid (SBF). The human fibroblast proliferation was tested on materials in cell culture. In in vivo experiments, toxicological tests, material degradation and tissue reactions were tested both in subcutaneous space and in experimental bone defects. The composites containing bioactive glass formed a unified layer of apatite on their surface in SBF. The size and amount of glass granules affected the degradation of polymer matrix, as well the material’s surface reactivity. In cell culture on the test materials the human gingival fibroblasts proliferated and matured faster compared with control materials. In in vitro tests a connective tissue capsule was formed around the specimens, and became thinner in the course of time. Foreign body cell reactions in toxicological tests were mild. In experimental bone defects the specimens with a high concentration of small bioactive glass granules (<45 μm) formed a dense apatite surface layer that restricted the bone ingrowth to material. The range of large glass granules (90-315 μm) with high concentrations formed the best bonding with bone, but slow degradation on the copolymer restricted the bone growth only in the superficial layers. In these studies, the handling properties of the material proved to be good and tissue reactions were mild. The reactivity of bioactive glass was retained inside the copolymer matrix, thus enabling bone conductivity with composites. However, the copolymer was noticed to degradate too slowly compared with the bone healing. Therefore, the porosity of the material should be increased in order to improve tissue healing.

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Sixty-nine entire male pigs with different halothane genotype (homozygous halothanepositive – nn-, n=36; and homozygous halothane negative – NN-, n=33) were fed with a supplementation of magnesium sulphate (Mg) and/or L-tryptophan (Trp) in the diet for 5days before slaughter. Animals were housed individually and were submitted to stressful ante mortem conditions (mixed in the lorry according to treatments and transported 1h on rough roads). Individual feed intake was recorded during the 5-day treatment. At the abattoir, pig behaviour was assessed in the raceway to the stunning system and during the stunning period by exposure to CO2. Muscle pH, colour, water holding capacity, texture and cathepsin activities were determined to assess meat quality. The number of pigs with an individual feed intake lower than 2kg/day was significantly different among diets (P<0.05; Control: 8.7%; Mg&Trp: 43.5%; Trp:17.4%) and they were considered to have inadequate supplement intake. During the antemortem period, 15.2% of pigs included in the experiment died, and this percentagedecreased to 8.7% in those pigs with a feed intake > 2kg/day, all of them from thestress-sensitive pigs (nn). In general, no differences were observed in the behaviour ofpigs along the corridor leading to the stunning system and inside the CO2 stunningsystem. During the stunning procedure, Trp diet showed shorter periods of muscularexcitation than control and Mg&Trp diets. The combination of a stressful ante mortemtreatment and Mg&Trp supplementation led to carcasses with high incidence of severeskin lesions. Different meat quality results were found when considering all pigs orconsidering only those with adequate supplement intake. In this later case, Trp increased pH45 (6.15) vs Control diet (5.96) in the Longissimus thoracis (LT) muscle (P<0.05) and pH at 24h (Trp: 5.59 vs C: 5.47) led to a higher incidence of dark, firm and dry (DFD) traits in SM muscle (P<0.05). Genotype affected negatively all the meat quality traits. Seventy-five percent of LT and 60.0% of the SM muscles from nn pigs wereclassified as pale, soft and exudative (PSE), while none of the NN pigs showed these traits (P<0.0001). No significant differences were found between genotypes on the incidence of DFD meat. Due to the negative effects observed in the Mg&Trp group in feed intake and carcass quality, the utilization of a mixture of magnesium sulphate and tryptophan is not recommended

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The topological solitons of two classical field theories, the Faddeev-Skyrme model and the Ginzburg-Landau model are studied numerically and analytically in this work. The aim is to gain information on the existence and properties of these topological solitons, their structure and behaviour under relaxation. First, the conditions and mechanisms leading to the possibility of topological solitons are explored from the field theoretical point of view. This leads one to consider continuous deformations of the solutions of the equations of motion. The results of algebraic topology necessary for the systematic treatment of such deformations are reviewed and methods of determining the homotopy classes of topological solitons are presented. The Faddeev-Skyrme and Ginzburg-Landau models are presented, some earlier results reviewed and the numerical methods used in this work are described. The topological solitons of the Faddeev-Skyrme model, Hopfions, are found to follow the same mechanisms of relaxation in three different domains with three different topological classifications. For two of the domains, the necessary but unusual topological classification is presented. Finite size topological solitons are not found in the Ginzburg-Landau model and a scaling argument is used to suggest that there are indeed none unless a certain modification to the model, due to R. S. Ward, is made. In that case, the Hopfions of the Faddeev-Skyrme model are seen to be present for some parameter values. A boundary in the parameter space separating the region where the Hopfions exist and the area where they do not exist is found and the behaviour of the Hopfion energy on this boundary is studied.

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Polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofuranes (PCDF) and polychlorinated biphenyls (PCB) are types of persistent and bioaccumulating organic pollutants with enhanced chronic toxicity and carcinogenic properties and can be considered as environmental indicators of anthropogenic activities since their occurrence in the environment can always be linked to anthropogenic activities. The present paper reviews the main sources and behaviour of these compounds in the environment as well as the risks they represent to man and biota.