Abstract
We consider an international trade economical model where two firms of different countries compete in quantities and can use three different strategies: (i) repealed collusion, (ii) deviation from the foreigner firm followed by punishment by he home country and then followed by repeated Cournot, or (iii) repeated deviation followed by punishment. In some cases (ii) and (iii) can be interpreted as dumping, We compute the profits of both firms for each strategy and we characterize the econc,mical parameters where each strategy is adopted by the firms.

Abstract

Abstract
Twelve adolescent athletes underwent, in a crossover-design study, 3 separate 90-min training sessions in the following conditions: no fluid ingestion allowed (NF), ad libitum ingestion of water (W), and ad libitum ingestion of a commercial 8% carbohydrate-electrolyte sports beverage (CSB). After each session athletes performed a set of basketball drills (2-point, 3-point, and free-throw shootout, suicide sprints, and defensive zigzags). Body weight (before and after sessions), rating of perceived exertion (RPE), urine color, and beverage acceptability were determined in each session. Athletes also completed a survey about their knowledge and behaviors regarding hydration and fluid replacement. The percentage of weight loss was significantly higher in NF (2.46% +/- 0.87%) than in the other 2 conditions (W, 1.08% +/- 0.67%, p = .006; CSB, 0.65% +/- 0.62%, p = .001) but also higher in W than CSB (p = .012). RPE was higher in NF (16.8 +/- 1.96) than in the W (14.2 +/- 1.99, p = .004) and CSB (13.3 +/- 2.06, p = .002) trials. Athletes' fluid intake was positively correlated with proper self-reported behaviors (r = .75, p = .005) and knowledge (r = .76, p = .004) about fluid and hydration. In conclusion, fluid restriction during exercise was associated with a greater level of dehydration and increased perceived exertion but had no impact on basketball performance compared with ad libitum drinking of water or a CSB. Athletes with more knowledge about hydration and better self-reported hydration behaviors ingested more fluids during training sessions.

Abstract
Objective: To estimate the prevalence of overweight and obesity in schoolchildren from Aveiro, Portugal, according to two criteria: the International Obesity Task Force (IOTF) and the US Centers for Disease Control and Prevention (CDC) cut-offs. Design: Weight, height and waist circumference were measured. Using the BMI, gender- and age-specific prevalences of overweight and obesity were determined according to the IOTF cut-offs extrapolated from an adult BMI of 25 and 30 kg/m(2) and the CDC cut-off values of 85th and 95th BMI percentile. Setting: Aveiro, Portugal. Subjects: A random representative sample of 905 children (457 boys; 448 girls) aged 7-9 years. Results: The prevalence of excess weight (overweight and obesity) was lowest according to IOTF cut-offs compared to CDC (28.1% v. 31.2%), especially obesity (8.1% v. 14.0%). However, the CDC and IOTF criteria have a strong agreement (Cohen's k=0.755; P<0.001). There were significant differences in excess weight between boys and girls according to the CDC (26.9% v. 35.7%; P=0.003). Obese children are younger and the majority present abdominal obesity. Conclusions: The present study shows a high prevalence of excess weight in Aveiro children, similar to other Portuguese regions and among the highest in Europe, especially in the female gender. The IOTF cut-off values give a lower prevalence of excess weight, namely obesity.

Abstract
Aims: To assess the cooking habits and skills of adolescents and its relation to Mediterranean diet adherence. Methods: Adolescents (N = 390) from the seventh, eighth and ninth grades in a school from a semi-urban region in northern Portugal were asked to fill in a questionnaire. The questionnaire assessed self-reported cooking habits and skills, for example enjoying and knowing how to cook and wanting to cook and learn more. Answers were taken on a scale from 0 to 5, 0 being 'no' and 5 being 'very much'. Learning sources, cooking frequency, and confidence in cooking ten particular foods were also assessed using the following answers: 'no, never', 'yes, with help from family/friends', 'yes, all by myself'. Adherence to Mediterranean diet was evaluated using the KIDMED index. Results: Adolescents who said that they cooked, did so usually between one and four times a month (56.2%). A high proportion of respondents had never cooked vegetables (57%), fish (51%) and soup (49%). Girls were more likely to have cooked foods listed in the questionnaire (p <= .002). Adolescents who did not know how to cook (8.7%) stated that the main reasons were that they had someone to cook for them (47%) and had no interest (35%). Those who knew how to cook mainly stated that they had learnt from their family (87.9%) and by themselves (7.9%). Most of our sample wanted 'to learn how to cook better' (M = 3.8, SD = 1.5), preferably with family/friends (82%) or by taking culinary courses (10%). The KIDMED index was poor for 7.2% of the sample, average for 50.8% and good for 42.1%. Adolescents with higher KIDMED scores were younger (p = .025), knew how to cook better (p < .001), cooked more often (p < .001), enjoyed cooking (p < .001), would like to cook more frequently (p < .001), and would like to learn how to cook better (p < .001). Conclusion: Almost one in every ten adolescents did not know how to cook. Vegetables, fish and soup were found to be foods that nearly half of the adolescents had never cooked. Female adolescents were more involved in cooking than males. Better cooking habits and skills were positively related with adolescents' adherence to the Mediterranean diet, which reinforces the idea that teaching cooking skills may have a positive impact in future food choice.

Abstract
Objective: To evaluate, in pre-adolescents and adolescents, the frequency of body image dissatisfaction and distortion and to assess the association between these factors and physical activity and body mass index (BMI). Design: Cross-sectional study. Methods: 234 children (10-17 years) from a Porto high school were evaluated. Dissatisfaction with body image (FID) was assessed by Collins' child figure drawings for pre-adolescents and adolescents. FID was calculated as the discrepancy between the "ideal figure" and the "perceived figure". Body image distortion (BID) was calculated as the discrepancy between the "perceived figure" and the "real figure". The Baecke questionnaire was applied to determine the habitual physical activity index (HPAI) of each participant. Results: Girls were more dissatisfied than boys with their body image (68.1% vs 52.9%). A high proportion of students of both genders and age groups revealed BID (71.8%) with 51.3% underestimating their body image and 20.5% overestimating it. A negative association was found between the FID and BID (girls: r = -.259, p = .006: boys: r = -.414, p < .001). High levels of physical activity were associated with a protective effect on FID, OR = 0.38, 95% CI [0.16, 0.87] for 3rd vs 1st quartile of HPAI: OR = 0.29, 95% CI [0.12, 0.86], for 4th vs 1st quartile of HPAI, both adjusted for BMI and gender, but HPAI was not associated with BID. Conclusion: FID and BID are highly frequent and inversely associated. BID increases directly with BMI percentiles in both genders while physical activity has a protective effect on dissatisfaction of body image.