What makes a host profitable? Parasites balance host nutritive resources against immunity.

Numerous host qualities can modulate parasite fitness, and among these, host nutritive resources and immunity are of prime importance. Indeed, parasite fitness increases with the amount of nutritive resources extracted from the host body and decreases with host immune response. To maximize fitness, parasites have therefore to balance these two host components. Yet, because host nutritive resources and immunity both increase with host body condition, it is unclear whether parasites perform better on hosts in prime, intermediate, or poor condition. We investigated blood meal size and survival of the ectoparasitic louse fly Crataerina melbae in relation to body condition and cutaneous immune response of their Alpine swift (Apus melba) nestling hosts. Louse flies took a smaller blood meal and lived a shorter period of time when feeding on nestlings that were experimentally food deprived or had their cutaneous immune response boosted with methionine. Consistent with these results, louse fly survival was the highest when feeding on nonexperimental nestlings in intermediate body condition. Our findings emphasize that although hosts in poor condition had a reduced immunocompetence, parasites may have avoided them because individuals in poor condition did not provide adequate resources. These findings highlight the fact that giving host immunocompetence primary consideration can result in a biased appraisal of host-parasite interactions.

Independent contribution of parental migrant status and educational level to adiposity and eating habits in preschool children.

Background/Objective:Little is known about the precise role of parental migrant status (MS) and educational level (EL) on adiposity and various eating habits in young children. Therefore, we assessed their independent contribution in preschoolers.Subjects/Methods:Of 655 randomly selected preschoolers, 542 (5.1±0.6 years; 71% of parental MS and 37% of low parental EL) were analysed. Body composition was measured by bioelectrical impedance. Eating habits were assessed using a semiqualitative food frequency questionnaire and analysed according to five messages developed by the Swiss Society for Nutrition, based on factors implicated in childhood obesity: (1) 'Drinking water and decreasing sweetened drinks', (2) 'Eating fruit and vegetables', (3) 'Decreasing breakfast skipping', (4) 'Reducing fatty and sweet foods' and (5) 'Reducing the intake of meals and snacks in front of television'.Results:Children of migrant and low EL parents had higher body fat, ate more meals and snacks while watching television and had more fruit and fatty foods compared with their respective counterparts (all P0.04). Children of low EL parents also consumed less water and vegetables compared with their counterparts (all P0.04). In most instances, we found an independent contribution of parental MS and EL to adiposity and eating habits. A more pronounced effect was found if both parents were migrants or of low EL. Differences in adiposity and eating habits were relatively similar to the joint parental data when assessed individually for maternal and paternal MS and EL.Conclusions:Parental MS and EL are independently related to adiposity and various eating habits in preschoolers.European Journal of Clinical Nutrition advance online publication, 3 November 2010; doi:10.1038/ejcn.2010.248.

Achievement goals in educational contexts: A social psychology perspective

Research on achievement goals usually defines mastery goals as the desire to acquire knowledge, and performance goals as the desire to outperform (or not to underperform) others. Educational contexts are most of the time social contexts, involving various persons and groups, of various hierarchical positions, and various cultural and ideological contexts. Surprisingly, most research in the achievement goal field has been conducted at an individual level of analysis. In the present paper, we will review the social consequences and antecedents of goal endorsement. This research indicates that goals strongly affect the way one behaves with co-learners. Moreover, it suggests that more than merely individual dispositions, goals reflect the social relation students have with other persons, institutions, and with the society to which they belong. We conclude this paper by setting an agenda for future achievement goal research.

Treatment of ruptured abdominal aortic aneurysm, a permanent challenge or a waste of resources? Prediction of outcome using a multi-organ-dysfunction score.

OBJECTIVES: in a retrospective study, attempts have been made to identify individual organ-dysfunction risk profiles influencing the outcome after surgery for ruptured abdominal aortic aneurysms. METHODS: out of 235 patients undergoing graft replacement for abdominal aortic aneurysms, 57 (53 men, four women, mean age 72 years [s.d. 8.8]) were treated for ruptured aneurysms in a 3-year period. Forty-eight preoperative, 13 intraoperative and 34 postoperative variables were evaluated statistically. A simple multi-organ dysfunction (MOD) score was adopted. RESULTS: the perioperative mortality was 32%. Three patients died intraoperatively, four within 48 h and 11 died later. A significant influence for pre-existing risk factors was identified only for cardiovascular diseases. Multiple linear-regression analysis indicated that a haemoglobin <90 g/l, systolic blood pressure <80 mmHg and ECG signs of ischaemia at admission were highly significant risk factors. The cause of death for patients, who died more than 48 h postoperatively, was mainly MOD. All patients with a MOD score >/=4 died (n=7). These patients required 27% of the intensive-care unit (ICU) days of all patients and 72% of the ICU days of the non-survivors. CONCLUSION: patients with ruptured aortic aneurysms from treatment should not be excluded. However, a physiological scoring system after 48 h appears justifiable in order to decide on the appropriateness of continual ICU support.

A two-week workshop to promote cardiovascular disease prevention programs in countries with limited resources.

Training is a crucial tool for building the capacity necessary for prevention and control of cardiovascular diseases (CVDs) in developing countries. This paper summarizes some features of a 2-week workshop aimed at enabling local health professionals to initiate a comprehensive CVD prevention and control program in a context of limited resources. The workshops have been organized in the regions where CVD prevention programs are being contemplated, in cooperation with health authorities of the concerned regions. The workshop's content includes a broad variety of issues related to CVD prevention and control, and to program development. Strong emphasis is placed on "learning by doing," and groups of 5-6 participants conduct a small-scale epidemiological study during the first week; during the second week, they draft a virtual program of CVD prevention and control adapted to the local situation. This practice-oriented workshop focuses on building expertise among anticipated key players, strengthening networks among relevant health professionals, and advocating the urgent need to tackle the emerging CVD epidemic in developing countries.

On the relationship between performance-approach goals and cognitive performance : when the desire to outperform others becomes interfering

Cette thèse explore dans quelle mesure la poursuite d'un but de performance-approche (i.e., le désir de surpasser autrui et de démontrer ses compétences) favorise, ou au contraire endommage, la réussite et l'apprentissage-une question toujours largement débattue dans la littérature. Quatre études menées en laboratoire ont confirmé cette hypothèse et démontré que la poursuite du but de performance-approche amène les individus à diviser leur attention entre d'une part la réalisation de la tâche évaluée, et d'autre part la gestion de préoccupations liées à l'atteinte du but-ceci empêchant une concentration efficace sur les processus de résolution de la tâche. Dans une deuxième ligne de recherche, nous avons ensuite démontré que cette distraction est exacerbée chez les individus les plus performants et ayant le plus l'habitude de réussir, ceci dérivant d'une pression supplémentaire liée au souhait de maintenir le statut positif de « bon élève ». Enfin, notre troisième ligne de recherche a cherché à réconcilier ces résultats-pointant l'aspect distractif du but de performance-approche-avec le profil se dégageant des études longitudinales rapportées dans la littérature-associant ce but avec la réussite académique. Ainsi, nous avons mené une étude longitudinale testant si l'adoption du but de performance-approche en classe pourrait augmenter la mise en oeuvre de stratégies d'étude tactiquement dirigées vers la performance-favorisant une réussite optimale aux tests. Nos résultats ont apporté des éléments en faveur de cette hypothèse, mais uniquement chez les élèves de bas niveau. Ainsi, l'ensemble de nos résultats permet de mettre en lumière les processus cognitifs à l'oeuvre lors de la poursuite du but de performance-approche, ainsi que d'alimenter le débat concernant leur aspect bénéfique ou nuisible en contexte éducatif. -- In this dissertation, we propose to investigate whether the pursuit of performance-approach goals (i.e., the desire to outperform others and appear talented) facilitates or rather endangers achievement and learning-an issue that is still widely discussed in the achievement goal literature. Four experiments carried out in a laboratory setting have provided evidence that performance- approach goals create a divided-attention situation that leads cognitive resources to be divided between task processing and the activation of goal-attainment concerns-which jeopardizes full cognitive immersion in the task. Then, in a second research line, we found evidence that high- achievers (i.e., those individuals who are the most used to succeed) experience, under evaluative contexts, heightened pressure to excel at the task, deriving from concerns associated with the preservation of their "high-achiever" status. Finally, a third research line was designed to try to reconcile results stemming from our laboratory studies with the overall profile emerging from longitudinal research-which have consistently found performance-approach goals to be a positive predictor of students' test scores. We thus set up a longitudinal study so as to test whether students' adoption of performance-approach goals in a long-term classroom setting enhances the implementation of strategic study behaviors tactically directed toward goal-attainment, hence favoring test performance. Our findings brought support for this hypothesis, but only for low-achieving students. Taken together, our findings shed new light on the cognitive processes at play during the pursuit of performance-approach goals, and are likely to fuel the debate regarding whether performance-approach goals should be encouraged or not in educational settings.