Síndrome de Mauriac: Uma Apresentação Rara de Uma Doença Mais Comum

Introdução: A diabetes mellitus tipo 1 (DM1) é uma doença metabólica crónica cuja incidência anual tem vindo a aumentar. Pode cursar com alterações sistémicas, como a hepatomegalia e o atraso de crescimento, decorrentes de controlo glicémico inadequado. Caso clínico: Adolescente de 14 anos com o diagnóstico de DM1 desdeos três anos de idade e com mau controlo glicémico, internada numa Unidade de Cuidados Intensivos por cetoacidose grave. Do exame objectivo destacavam-se baixa estatura, hepatomegalia não dolorosa e estadio pubertário P1, M2 de Tanner. Analiticamente apresentava aumento das transaminases, hipercolestorolemia e hipertrigliceridemia. Discussão: A síndrome de Mauriac, caracteriza -se por: DM tipo 1 mal controlada, baixa estatura, atraso pubertário, hipercolesterolémia, aumento das transaminases e hepatomegalia por depósito hepático de glicogénio. O mecanismo fi siopatológico não está totalmente esclarecido, sendo provavelmente a combinação de vários factores etiológicos. É uma situação rara, cujo diagnóstico, essencialmente clínico, assume extrema importância dada a reversibilidade do quadro com a optimização terapêutica.

Consensus of Official Position of IOF/ISCD FRAX Initiatives in Asia-Pacific Region.

The fracture risk assessment tool (FRAX(®)) has been developed for the identification of individuals with high risk of fracture in whom treatment to prevent fractures would be appropriate. FRAX models are not yet available for all countries or ethnicities, but surrogate models can be used within regions with similar fracture risk. The International Society for Clinical Densitometry (ISCD) and International Osteoporosis Foundation (IOF) are nonprofit multidisciplinary international professional organizations. Their visions are to advance the awareness, education, prevention, and treatment of osteoporosis. In November 2010, the IOF/ISCD FRAX initiative was held in Bucharest, bringing together international experts to review and create evidence-based official positions guiding clinicians for the practical use of FRAX. A consensus meeting of the Asia-Pacific (AP) Panel of the ISCD recently reviewed the most current Official Positions of the Joint Official Positions of ISCD and IOF on FRAX in view of the different population characteristics and health standards in the AP regions. The reviewed position statements included not only the key spectrum of positions but also unique concerns in AP regions.

Nest distribution varies with dispersal method and familiarity-mediated aggression for two sympatric ants

Dispersal mechanisms and competition together play a key role in the spatial distribution of a population. Species that disperse via fission are likely to experience high levels of localized competitive pressure from conspecifics relative to species that disperse in other ways. Although fission dispersal occurs in many species, its ecological and behavioural effects remain unclear. We compared foraging effort, nest spatial distribution and aggression of two sympatric ant species that differ in reproductive dispersal: Streblognathus peetersi, which disperse by group fission, and Plectroctena mandibularis, which disperse by solitary wingless queens. We found that although both species share space and have similar foraging strategies, they differ in nest distribution and aggressive behaviour. The spatial distribution of S. peetersi nests was extremely aggregated, and workers were less aggressive towards conspecifics from nearby nests than towards distant conspecifics and all heterospecific workers. By contrast, the spatial distribution of P. mandibularis nests was overdispersed, and workers were equally aggressive towards conspecific and heterospecific competitors regardless of nest distance. Finally, laboratory experiments showed that familiarity led to the positive relationship between aggression and nest distance in S. peetersi. While unfamiliar individuals were initially aggressive, the level of aggression decreased within 1 h of contact, and continued to decrease over 24 h. Furthermore, individuals from near nests that were not aggressive could be induced to aggression after prolonged isolation. Overall, these results suggest that low aggression mediated by familiarity could provide benefits for a species with fission reproduction and an aggregated spatial distribution.

Bone properties and skeletal maturity in adolescent males, as assessed by quantitative ultrasound

ABSTRACT Background: Previous studies have implied that weight-bearing, intense and prolonged physical activities optimize bone accretion during the grow^ing years. The majority of past inquiries have used dual-energy X-ray absorptiometry (DXA) to examine bone strength and hand-wrist radiography to determine skeletal maturity in children. Recently, quantitative ultrasound (QUS) technologies have been developed to examine bone properties and skeletal maturity in a safe, noninvasive and cost-effective manner. Objective: The purpose of this study was to compare bone properties and skeletal maturity in competitive male child and adolescent athletes with minimallyactive, age-matched controls, using QUS technology. >. Methods: In total, 224 males were included in the study. The 115 pre-pubertal boys aged 10-12 years consisted of control, minimally-active children (n=34), soccer players (n=26), gymnasts (n=25) and hockey players (n=30). In addition, the 109 late-pubertal boys aged 14-16 years consisted of control, minimally-active adolescents (n=31), soccer players (n=30), gymnasts (n=17) and hockey players (n=31). The athletic groups were elite level players that predominantly trained year-round. Physical activity, nutrition and sports participation were assessed with various questionnaires. Anthropometries, such as height, weight and relative body fat percentage (BF%) were assessed using standard measures. Skeletal strength and age were evaluated using bone QUS. Lastly, salivary testosterone (sT) concentration was measured using Radioimmunoassay (RIA). Results: Within each age group, there were no significant differences between the activity groups in age and pubertal stage. An age effect was apparent in all variables, as expected. A sport effect was noted in all physical characteristics: the child and adolescent gymnasts were shorter and lighter than other sports groups. Adiposity was greater in the controls and in the hockey players. All child subjects were pubertal stage (fanner) I or II, while adolescent subjects were pubertal stage IV or V. There were no differences in daily energy and mineral intakes between sports groups. In both age groups, gymnasts had a higher training volume than other athletic groups. Bone speed of sound (50s) was higher in adolescents compared with the children. Gymnasts had signifieantly higher radial 50S than controls, hockey and soccer players in both age cohorts. Hockey athletes also had higher radial 50S than controls and soccer players in the child and adolescent groups, respectiyely. Child gymnasts and soccer players had greater tibial 50S compared with the hockey players and control groups. Likewise, adolescent gymnasts and soccer players had higher tibial SoS compared with the control group. No interaction was apparent between age and type of activity in any of the bone measures. » Lastly, maturity as assessed by sT and secondary sex characteristics (Tanner stage) was not different between sports group within each age group. Despite the similarity in chronological age, androgen levels and sexual maturity, differences between activity groups were noted in skeletal maturity. In the younger group, hockey players had the highest bone age while the soccer players had the lowest bone age. In the adolescent group, gymnasts and hockey players were characterized by higher skeletal maturity compared with controls. An interaction between the age and sport type effects was apparent in skeletal maturity, reflecting the fact that among the children, the soccer players were significantly less mature than the rest of the groups, while in the adolescents, the controls were the least skeletally mature. Summary and Conclusions: In summary, radial and tibial SOS are enhanced by the unique loading pattern in each sport (i.e, upper and lower extremities in gymnastics, lower extremities in soccer), with no cumulative effect between childhood and adolescence. That is, the effect of sport participation on bone SOS was apparent already among the young athletes. Enhanced bone properties among athletes of specific sports suggest that participation in these sports can improve bone strength and potential bone health.

Determinants of left ventricular mass as measured by Doppler echocardiography in pre-adolescents

This study examined factors contributing to the differences in left ventricular mass as measured by Doppler echocardiography in children. Fourteen boys (10.3 ± 0.3 years of age) and 1 1 girls (10.5 ± 0.4 years of age) participated in the study. Height and weight were measured, and relative body fat was determined from the measurement of skinfold thickness according to Slaughter et al. (1988). Lean Body Mass was then calculated by subtracting the fat mass from the total body mass. Sexual maturation was self-assessed using the stages of sexual maturation by Tanner (1962). Both pubic hair development and genital (penis or breast for boys and girls respectively) development were used to determine sexual maturation. Carotid Pulse pressure was assessed by applanation tomometry in the left carotid artery. Cardiac mass was measured by Doppler Echocardiography. Images of cardiac structures were taken using B-Mode and were then translated to M- Mode. The dimensions at the end diastole were obtained at the onset of the QRS complex of the electrocardiogram in a plane through a standard position. Measurements included: (a) the diameter of the left ventricle at the end diastole was measured from the septum edge to the endocardium mean border, (b) the posterior wall was measured as the distance from to anterior wall to the epicardium surface, and (c) the interventricular septum was quantified as the distance from the surface of the left ventricle border to the right ventricle septum surface. Systolic time measurements were taken at the peak of the T-wave of the electrocardiogram. Each measurement was taken three to five times before averaging. Average values were used to calculate cardiac mass using the following equation (Deveraux et al. 1986). Weekly physical activity metabolic equivalent was calculated using a standardize activity questionnaire (Godin and Shepard, 1985) and peakV02 was measured on a cycloergometer. There were no significant differences in cardiovascular mesurements between boys and girls. Left ventricular mass was correlated (p<0.05) with size, maturation, peakV02 and physical activity metabolic equivalent. In boys, lean body mass alone explained 36% of the variance in left ventricular mass while weight was the single strongest predictor of left ventricular mass (R =0.80) in girls. Lean body mass, genital developemnt and physical activity metabolic equivalent together explained 46% and 81% in boys and girls, respectively. However, the combination of lean body mass, genital development and peakV02 (ml kgLBM^ min"') explained up to 84% of the variance in left ventricular mass in girls, but added nothing in boys. It is concluded that left ventricular mass was not statistically different between pre-adolescent boys and girls suggesting that hormonal, and therefore, body size changes in adolescence have a main effect on cardiac development and its final outcome. Although body size parameters were the strongest correlates of left ventricular mass in this pre-adolescent group of children, to our knowledge, this is the first study to report that sexual maturation, as well as physical activity and fitness, are also strong associated with left ventricular mass in pre-adolescents, especially young females. Arterial variables, such as systolic blood pressure and carotid pulse pressure, are not strong determinants of left ventricular mass in this pre-adolescent group. In general, these data suggest that although there is no gender differences in the absolute values of left ventricular mass, as children grow, the factors that determine cardiac mass differ between the genders, even in the same pre-adolescent age.

Secretory immunity in overweight and obese versus normal-weight early-and late-pubertal females

Obesity is a condition associated with a wide variety of health problems including hypertension, dyslipidemia, diabetes mellitus, certain forms of cancer, cardiovascular disease, and gallstones (157). TTiere is growing evidence that obesity may also be related to compromised immune function due to altered metabolic, psychological, and physical attributes (93). The aim of this study was to compare: a) immunity-related variables such as frequency of upper respiratory tract infections (URTI) and salivary secretory immunoglobulin A (sIgA) levels between overweight/obese (OB) and normal weight (NW) early-pubertal and late-pubertal girls, and b) stress-related variables such as Cortisol, melatonin, the melatonin/cortisol ratio, testosterone and the testosterone/cortisol ratio. Physical activity levels, stress indicators, and fatigue were used to explain potential differences in the dependent variables. It was hypothesized that the OB females would have lower melatonin (M) and higher Cortisol (C) and testosterone (T) levels compared with NW girls, regardless of maturity status. The altered levels of melatonin, Cortisol, and testosterone, would result in decreased M/C and T/C ratios, despite the increase in testosterone in OB females. It was hypothesized that this altered hormonal status results in a compromised immunity marked by higher frequency of upper respiratory tract infections (URTI) and decreased levels of secretory immunoglobulin A (sIgA). It was also hypothesized that OB girls would participate in less hours of physical activity than their NW counterparts and that this would relate to their stress and immunity levels. Forty (16 early- and 24 late-pubertal) overweight and obese females were compared to fifty-three (27 eariy- and 26 late-pubertal) age-matched normal-weight control subjects. Participants were categorized as early-pubertal (EP) or late-pubertal (LP) using Tanner self-staging of secondary sex characteristics. Subjects were classified into the two adiposity groups according to relative body fat (%BF), where normal weight (NW) subjects had a %BF less than 25%, and overweight and obese (OB) subjects had a %BF greater than 27.5%. Participants completed a number of questionnaires and information was collected on menstrual history, smoking history, alcohol and caffeine consumption, and medical history. Following the determination of maturity status, a complete anthropometric assessment was made including height, body mass, and body composition. All questionnaires and measurements were completed during a one-hour visit between 1 500 and 1900 hours Relative body fat was assessed using bioelectrical impedance analysis. Resting saliva samples were obtained and assayed (ELISA) for testosterone, Cortisol, melatonin and secretory immunoglobulin A. Physical activity was self-reported using the Godin- Shephard Leisure time questionnaire, and quantified using Actigraph GTIM accelerometers, which participants wore for seven consecutive days from the time they woke up in the morning, until the time they went to bed. Late-pubertal girls also completed questionnaires on their perceived stress and fatigue. Finally, all participants also filled out a one-month health log to record frequency of symptoms of upper respiratory tract infections (URTI). Significant age effects were found for testosterone, Cortisol, incidence of sickness, and sIgA when controlling for physical activity, however there were no significant effects of adiposity on any of the variables. There was a trend which neared-significance for an effect of adiposity on sIgA (p=0.01). There were no significant differences between the groups on the total selfreported leisure-time physical activity in METs per week, however EP girls recorded significantly greater levels of moderate, hard, and very hard physical activity from accelerometers. Results of the perceived stress and fatigue questionnaires in late-pubertal girls demonstrated that contrary to what was hypothesized, NW girls reported more stress and more fatigue than OB girls. Results of the present study suggest that excess adiposity in early- and latepubescent girls may not have a negative impact on immunity as hypothesized.

The association between body composition and arterial stiffness in peri-pubescent children

The objective of this study was to examine the association between body composition and arterial stiffuess in peri-pubescent boys and girls. Differences in arterial distensibility were measured in 68 children (45 normal weight, 12 overweight, and 11 obese) between the ages of9 to 12 years. Weight classification was based on age and gender-specific body mass index cut-offs, while pubertal maturation was self-reported using Tanner staging. Distensibility was determined using two-dimensional, B-Mode echo Doppler ultrasound to measure changes at the right common carotid artery (CCA) diameter changes, while carotid pulse pressure (cPP) was measured at the left CCA by applanation tonometry. One-way ANOV A analysis revealed significant differences (p<0.001) in all anthropometric measures between the normal weight and overweight children, as well as the normal weight and obese children. Body stature was only higher in obese children compared to normal weight children (p<0.01). No significant differences were found between groups regarding age or Tanner stage. Common carotid artery distensibility showed a significant difference (p<0.01) between normal weight children (0.008 ± 0.002 mmHg-1 ) compared to obese children (0.005 ± 0.002 mmHg-1 ), with a borderline significant difference between the normal and overweight subjects (p=0.06). There was no significant effect for gender between males and females across all independent variables. The strongest determinants of distensibility in children were cPP (r= -0.52, p

Autonomic Cardiovascular Control in Children and Adolescents

This thesis investigated the impact of pubertal maturation and sex on cardiovagal baroreflex sensitivity (BRS) and arterial properties of the common carotid artery (CCA), and the relationship between CCA arterial properties and BRS. This thesis also investigated the effect of orthostatic stress on arterial properties of the CCA and carotid sinus (CS), as well as their impact on BRS in response to orthostatic stress. Children and adolescents between the ages of 8-18 years were examined. To assess pubertal maturation participants were organized into five pubertal groups based on the criteria of Tanner. BRS was assessed by transfer function analysis in the low frequency range (0.05 – 0.15Hz). Pulse pressure (PP) was measured at the CCA (PPCCA) and CS (PPCS) using applanation tonometry, and at the finger (PPFinger) using photoplethysmography. Ultrasound sonography and applanation tonometry were used to determine the distensibility coefficient (DC) at the CCA (DCCCA) and CS (DCCS). A moderate posture stimulus was implemented by passively moving participants into a 50° seated-recumbent (SR) position. The results demonstrated a sex-by-maturation interaction on BRS (p= 0.019). BRS decreased from early- to post-puberty in males (p<0.01), and remained unchanged in females. Females demonstrated greater BRS compared to males post-puberty (p<0.05). CCA distensibility was not affected by sex or maturation and was not related to BRS. PPCS was greater than PPCCA (p<0.001), while PPFinger was greater than both PPCCA (p<0.001) and PPCS (p<0.001). In response to SR, the relative change in PPFinger was significantly different than the relative change in PPCCA (p<0.001) and PPCS (p<0.001), while the relative change between PPCCA and PPCS were not different. Finally, in response to SR there was a significant decrease in DCCS (p=0.001), but not DCCCA. The relative change in BRS in response to SR was significantly correlated to the relative change in DCCS (p=0.004), but not DCCCA. The findings demonstrated an important sex-dependent maturation effect on BRS in children and adolescents that was not explained by CCA distensibility. Also, the CS and CCA responded differently to orthostatic stress. The CS was more suitable to evaluate the effect of arterial distensibility on BRS in response to posture change.

La perception du risque terroriste et de ses conséquences sur la gestion de la sécurité dans le système de transport en commun de Montréal

Dans cet ouvrage, nous cherchons à comprendre l‘impact des perceptions sur la production et la gestion de la sécurité dans le réseau du transport en commun de Montréal. Quinze entrevues de recherche ont été effectuées avec des policiers de l‘Unité-Métro pour dégager les principaux éléments qui entrent dans la conception du risque. Les policiers sont appelés à travailler dans un environnement où, d‘une part, il n‘y a jamais eu d‘attaques terroristes, mais d‘autre part qui demeure une cible potentielle à la fois pour les experts, les gouvernements et dans la culture populaire. Nos résultats montrent que les policiers se développent une perception du risque qui leur est propre. En général, ils ont une attitude pragmatique qui leur permet de relativiser les situations et de décider lesquelles nécessitent une intervention de leur part. De plus, les policiers adoptent des stratégies de justification et de protection qui minimisent la perception du risque. Nos participants soulignent que ces stratégies sont nécessaires pour leur permettre d‘effectuer leurs tâches quotidiennes. Ainsi, afin d‘échapper à la paranoïa, les policiers évitent de penser à la menace terroriste et focus plutôt leur attention sur la criminalité sur laquelle ils ont l‘impression d‘avoir un pouvoir réel. Toutefois, la vigilance reste de mise. Malgré que les policiers ne conçoivent pas le risque de la même manière que les gestionnaires, la présence de l‘Unité-Métro demeure un élément important de production de la sécurité sur le terrain.

L’exercice du métier policier en opération de paix : quelles pratiques? quelles retombées?

La participation des organisations policières à des opérations de paix des Nations Unies est un phénomène datant de quelques décennies, mais qui suscite de plus en plus d’intérêt dans la communauté scientifique ainsi que chez les organisations contributrices. À titre indicatif, en 2010, près de 13 000 policiers étaient déployés dans 13 opérations de paix des Nations Unies, ce qui représente une augmentation de 810 % par rapport aux 1 600 policiers qui étaient déployés en 1995 . Cette augmentation marquée de la participation policière à ce type d’opération à l’étranger remet en question les conceptions traditionnelles que les chercheurs avaient de l’institution policière. Bel exemple de la transnationalisation des organisations policières, la participation des policiers à des opérations de paix soulève toutefois de nombreux questionnements. Alors que la majorité des recherches se sont penchées sur les problématiques opérationnelles reliées à l’envoi de policiers dans ces zones en sortie de guerre, peu d’entre elles se sont penchées sur les questions reliées au post-déploiement, c'est-à-dire à la réintégration des policiers dans leur société d’origine. Puisque la contribution des services de police québécois aux missions de paix des Nations Unies semble maintenant faire partie intégrante de la mission de certaines de ces organisations, il serait intéressant de valider quelles sont les retombées organisationnelles de cette participation. C’est précisément dans cette lignée que le présent mémoire prend tout son sens. Plus précisément, la présente recherche a pour objectif d’étudier la relation entre la participation d’un policier à ce type de mission et la modification de ses habitudes et méthodes de travail lors de sa réintégration dans son unité d’origine. La perspective organisationnelle utilisée dans ce mémoire est novatrice au sens où elle permet de questionner l’utilité et les retombées de ces missions, non pas sur les sociétés bénéficiaires de l’aide internationale, mais plutôt sur les acteurs contribuant à la mise en place de ces missions. De tels questionnements sont pertinents si l’on veut mesurer les retombées que peuvent avoir les opérations de paix sur les policiers eux-mêmes, sur les organisations policières participantes, mais aussi sur les services fournis aux citoyens par ces mêmes organisations. Les données qui nous permettront de répondre à ces questions proviennent de dix-neuf entretiens semi-directifs réalisés auprès de policiers de la Sûreté du Québec qui ont participé à une mission de paix en Haïti entre 2005 et 2010. En somme, il est possible d’affirmer que les méthodes de travail d’un policier revenant de mission peuvent être modifiées positivement ou négativement par différents facteurs tels que l’acquisition de compétences, la modification des traits de personnalité ou encore par un changement au niveau de la perception qu’on ces policiers de leur travail.

Dynamiques de participation et processus de cristallisation de bandes armées dans les crimes de masse : retour sur la violence en ex-Yougoslavie

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

Macro-analyse quantitative des facteurs d’émergence des émeutes : une nouvelle approche de compréhension mondiale des violences collectives

Les calculs statistiques ont été effectués à l'aide du logiciel SPSS.

L’exercice du raisonnement clinique d’infirmières du programme SIPPE lorsqu’elles priorisent leurs interventions auprès de familles qui vivent en contexte de vulnérabilité.

Cette recherche qualitative avait pour but d’explorer le raisonnement clinique d’infirmières de première ligne en CSSS/CLSC lorsqu’elles priorisent leurs interventions auprès de familles vivant en contexte de vulnérabilité dans le cadre du programme des Services intégrés en périnatalité et pour la petite enfance (SIPPE). Il s’agit d’une étude de cas qui comporte un échantillon intentionnel de sept épisodes de soins impliquant deux infirmières auprès de sept familles en période postnatale lorsqu’elles priorisent leurs interventions. La collecte de données a procédé par méthode think aloud, suivie d’entretiens semi-dirigés auprès des infirmières. Une analyse qualitative des données a été effectuée selon des méthodes interprétatives et par comptage de catégories. Ces dernières ont été formulées et mises en relation en s’inspirant de la modélisation du processus de raisonnement clinique de Tanner (2006) ainsi que des stratégies de raisonnement clinique proposés par Fonteyn (1998). Au terme de cette étude, le processus de raisonnement clinique ne semble pas être différent selon le type de priorité d’intervention auprès de familles en contexte de vulnérabilité, particulièrement lorsque nous distinguons la priorité selon un degré d’urgence (prioritaire ou secondaire). Aussi, nous constatons qu’il existe peu de diversité dans les processus de raisonnement clinique mobilisés à travers les sept épisodes de soins; et qu’un processus narratif de raisonnement est fréquent. Si une famille exprime un besoin urgent, l’infirmière y répond prioritairement. Par ailleurs, lorsque des conditions suggèrent un potentiel accru de vulnérabilité des familles, un mode de raisonnement clinique plus systématique, qui comporte une collecte et une mise en relation d’informations afin de formuler une proposition pour soutenir le passage à l’action, semble être mobilisé pour prioriser l’intervention. Il en est ainsi s’il s’agit d’un premier bébé, que la famille n’utilise pas d’autres ressources formelles de soutien. Autrement, s’il s’agit d’un deuxième bébé et que les familles utilisent d’autres ressources, les infirmières tendent plutôt à appliquer une routine d’intervention SIPPE. Aussi, cette recherche témoigne de l’engagement soutenu des infirmières auprès de familles vivant d’importants défis. Il importe toutefois de soutenir le développement d’un répertoire plus varié de processus de raisonnement clinique afin de renforcer leur capacité de prioriser leur intervention qui se déroule dans un contexte de multiples contraintes organisationnelles et interpersonnelles.

Analyse de l'évolution de l'Administration canadienne de la sûreté du transport aérien

La présente étude a analysé l’évolution de l’Administration Canadienne de la Sureté du Transport Aérien (ACSTA) depuis sa mise en place jusqu’aujourd’hui, ainsi que les acteurs individuels ou institutionnels impliqués dans ce processus. L’ACSTA gravite dans un champ organisationnel ‐ensemble d’organisations qui constituent un domaine reconnu de la vie institutionnelle (DiMaggio et Powell, 1983)-­ au sein duquel agissent différents acteurs qui ont influencé non seulement sa création, mais qui ont continué à jouer un rôle important tout au long de son évolution. Nous avons défini le champ de la sûreté aérienne et au sein de celui‐ci, nous avons analysé les mécanismes institutionnels, tout en identifiant et définissant le rôle des différents acteurs en présence. Il ressort de nos analyses que principalement deux types de contraintes institutionnelles (DiMaggio et Powell, 1983) ont influencé la création et le développement de l’ACSTA. Premièrement, mis à part les contraintes coercitives émanant de la règlementation internationale de l’Organisation de l’Aviation Civile Internationale, il apparait que d’autres contraintes du même type proviennent du gouvernement américain, par le biais de pressions visant à la mise en place de mesures sécuritaires, tant au moment de la création que tout le long de l’évolution de l’organisation. Il est à noter, cependant, le rôle du terrorisme et des tentatives d’attentat comme provocant de telles contraintes. Deuxièmement, nous avons identifié des contraintes du type normatif, c’est-à‐dire celles qui proviennent des valeurs, des normes et du bagage professionnel lié à la sécurité et à la sureté aérienne. Il apparait que les contraintes normatives agissent constamment alors que les contraintes coercitives surgissent ponctuellement tout au long de la période analysée.