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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

The relationship between training load and incidence of injury and illness over a pre-season at an Australian Football League Club

PIGGOTT, Benjamin, ben_piggott@yahoo.com January 2008 (has links)
In any competitive sporting environment, it is crucial to a team's success to have the maximum number of their players free from injury and illness and available for selection in as many games as possible throughout the season. The training programme of the club, and therefore training load, can have an impact on the incidence of injury and illness amongst the players. The purpose of this study was to investigate the relationship between the training load and the incidence of injury and illness over an entire pre-season at an Australian Football League (AFL) club. Sixteen players were subjects; all full time professional male AFL players (mean + or - standard deviation; age 23.8 + or - 5.1 years; height 188.9 + or - 7.4 m; weight 90.9 + or - 9.2 kg). A longitudinal research design was employed, where training load, injury and illness were monitored over a 15 week pre-season and Pearson Correlation Coefficients were used to examine relationships.
262

Détermination des contraintes résiduelles dans les revêtements par diffraction des rayons X en faible incidence

Peng, Jun 07 1900 (has links) (PDF)
Une nouvelle méthode d'analyse par diffraction des rayons X (DRX) en incidence rasante, notée sin2 *, a été développée pour répondre à la demande d'analyse du niveau et la distribution des contraintes résiduelles (CR) dans un revêtement. La méthode est basée sur la technique de DRX en faible incidence et elle tient compte des orientations cristallines et de la géométrie de mesure (l'angle d'incidence, les angles et de l'épaisseur de couche à analyser) afin de connaître la profondeur de pénétration exacte du faisceau incident. Par cette méthode, on peut non seulement évaluer le niveau moyen des CR dans le revêtement, mais également déterminer le gradient et la distribution en variant l'angle d'incidence pour différentes profondeurs de pénétration voulues. Les incertitudes de mesure ont été ensuite évaluées, et l'influence de la rugosité de surface a été étudiée avec des éprouvettes sous sollicitation mécanique connue. Un modèle analytique a été établi pour la correction de l'influence de la rugosité sur la détermination des CR. Par ailleurs, une éprouvette en alliage base nickel rectifiée avec un fort gradient de contrainte résiduelle a été étudiée en appliquant notre méthode sin2 * pour évaluer la sensibilité de la méthode développée. Deux séries d'échantillons de revêtements (Cuivre sur substrat Ni élaboré par le procédé PVD, et Tantale biphasé sur substrat Ti élaboré par le procédé CVD) ont été étudiées avec la nouvelle méthode d'étude afin d'analyser la distribution des CR. La comparaison des résultats avec deux autres méthodes a montré que cette nouvelle méthode d'évaluation par DRX en faible incidence est fiable et facile à utiliser pour déterminer le niveau et la distribution des CR.
263

Evaluation du dépistage du cancer du sein par mammographie : estimation du surdiagnostic, de la participation des femmes après un résultat faux positifs et de l'incidence des cancers de l'intervalle

Seigneurin, Arnaud 03 October 2011 (has links) (PDF)
L'intérêt du programme de dépistage du cancer du sein par mammographie résulte de la balance entre la réduction de la mortalité et les effets indésirables du programme. L'objectif de ce travail était d'évaluer trois aspects du programme de dépistage dans le département de l'Isère. Nous avons utilisé une méthode Approximate Bayesian Computation pour estimer le surdiagnostic lié au dépistage par mammographie de cancers non évolutifs. Ils représentaient respectivement 1,5% (IC95% : 0,3% - 2,9%) et 28,0% (IC95% : 2,2% - 59,8%) des cancers invasifs et in situ diagnostiqués. Nous avons réalisé une revue de la littérature des méthodes d'estimation du surdiagnostic et montré sur des données simulées que les méthodes basées sur les taux d'incidence annuels étaient les moins sensibles aux biais. Par ailleurs, l'incidence des cancers de l'intervalle était inférieure lorsque les mammographies étaient réalisées avec deux clichés par sein au lieu d'un seul, aussi bien à 12 que à 24 mois. Enfin, l'exclusion du diagnostic de cancer après la réalisation d'une imagerie supplémentaire, d'une biopsie ou un suivi radiologique diminuait la participation lors de la prochaine invitation au dépistage organisé. En conclusion, l'intérêt du programme de dépistage du cancer du sein par mammographie n'est pas remis en cause avec 1,4 décès évité pour un cancer surdiagnostiqué (in situ ou invasif).
264

Les cancers de la cavité buccale et de l'oropharynx dans le monde : incidence internationale et classification TNM dans les registres du cancer

De Camargo Cancela, Marianna 13 December 2010 (has links) (PDF)
L'objectif de ces travaux est de connaître et évaluer les caractéristiques épidémiologiques des cancers de la cavité orale et de l'oropharynx. Ces deux localisations partagent des facteurs de risque en commun, et sont de fait souvent regroupées dans les études épidémiologiques. Cependant, la découverte de facteurs de risque spécifiques, telle l'infection par le virus du papillome humain pour les cancers de l'oropharynx, nous conduit à fournir des taux d'incidence spécifiques avec la classification anatomique de ces cancers. En réorganisant les données disponibles dans la base des données du Centre International de Recherche sur le Cancer, nous avons recherché les cas incidents au niveau mondial et recalculé les taux d'incidence dans les registres de 60 pays, pendant la période 1998-2002. La classification TNM n'est pas disponible dans les bases de données du CIRC. Nous avons identifié et contacté les registres du cancer qui ont déclaré son recueil. Cela nous a permis de créer et structurer une base des données innovante et inédite, dont les informations ont été analysées par rapport à la qualité. Finalement nous avons comparé la distribution de stades précoces et avancés dans 8 pays. Les résultats montrent que l'incidence des cancers de la cavité buccale et de l'oropharynx est très hétérogène au niveau mondial par rapport à la sous localisation des tumeurs, à l'âge d'incidence, au ratio homme/femme et au stade clinique.
265

Biological optimization of angle of incidence and intensity modulation in breast and cervix cancer radiation therapy

Costa Ferreira, Brigida January 2004 (has links)
<p>Biological treatment optimization aim at improving radiation therapy by accounting for the radiobiological tumour and normal tissues response properties when optimizing the dose delivery. Generally traditional methods, using only dosimetrical measures, disregard the nonlinear radiation response of different tumours and normal tissues. The accumulated knowledge on tissue response to radiation, in the form of more accurate dose response relations, cell survival models and their associated biological parameters, alongside with the tools for biological treatment plan optimization, has allowed the present investigation on the potential merits of biologically based treatment optimization in radiation therapy.</p><p>With a more widespread implementation of intensity modulated radiation therapy in the clinic, there is an increasing demand for faster and safer treatment delivery techniques. In this thesis biological treatment plan optimization, using the probability to achieve complication free tumour control as the quantifier for treatment outcome, was applied to radiation therapy of early breast cancer and advanced cervix cancer. It is shown that very conformal dose distributions can generally be produced with 3 or 4 optimally orientated coplanar intensity modulated beams, without having clinically significant losses in treatment outcome from the optimal dose distribution.</p><p>By using exhaustive search methods, the optimal coplanar beam directions for intensity modulated photon beams for early breast cancer and the optimal non-coplanar directions for an advanced cervix cancer were investigated. Although time consuming, exhaustive search methods have the advantage of revealing most features involving interactions between a small number of beams and how this may influence the treatment outcome. Thus phase spaces may serve as a general database for selecting an almost optimal treatment configuration for similar patients. Previous knowledge acquired with physically optimized uniform beam radiation therapy may not apply when intensity modulated biological optimization is used. Thus unconventional treatment directions were sometimes found.</p>
266

An evaluation of the adult education initiative relative labor market training

Stenberg, Anders January 2003 (has links)
<p>This thesis consists of three papers which evaluate the effects of the Adult Education Initiative (AEI) in Sweden relative to the vocational part of Labor Market Training (LMT).</p><p>Paper [I] studies unemployment incidence and unemployment duration for participants in the AEI relative to LMT. When evaluating the relative program effects on duration, one needs to take into account both the problem of selection and the fact that the outcome variable is right hand censored. The method used is an instrumental variable adaptation of the symmetrically trimmed least squares estimator. A bivariate probit model is used in order to study unemployment incidence. The results indicate a beneficial effect of the AEI relative to LMT on unemployment incidence, but longer duration in unemployment among the AEI participants.</p><p>Paper [II] uses annual wage earnings in 1999 to compare the AEI and LMT for individuals that do not continue in education following program completion. Two separate estimation methods are used, the classical selection model and the method of matching on the propensity score. The results of both methods indicate negative effects of the AEI relative to LMT on wage earnings. The earnings effect of the AEI for individuals with a weak position in the labor market is particularly poor, implying that the official target to assist those individuals appear not to have succeeded.</p><p>Paper [III] employs data for those enrolled in 1997 as well as 1998 to study the annual wage earnings of 1999 and 2000 and data on attachment to branches of employment before and after program. Data on branches of employment indicate less mobility among the AEI participants. This is largely due to a stronger attachment to the public service sector. The analysis of wage earnings of the sample enrolled in 1997, indicate that the effects on wage earnings tended to be more advantageous for the AEI in 2000 rather than 1999, possibly implying a lag in the effects of the program.</p>
267

Ultraviolet Radiation and Squamous Cell Carcinoma in Human Skin

Wassberg, Cecilia January 2001 (has links)
<p>Ultraviolet radiation (UVR) is a major risk factor for development of skin cancer. UVR-induced DNA damage and a dysfunctional p53 protein are important steps in the development of squamous cell carcinoman in human skin (SCC). The aim of the present investigation was to analyze incidence trends of SCC in Sweden, quantify the risk of second primary cancer after SCC and further analyze the effects of UVR and p53 protein in human skin <i>in vivo</i> and <i>in vitro</i>. The effect of photoprotection by sunscreens was also evaluated. </p><p>We found that the age-standardized incidence rate of SCC in Sweden increased substantially in both men and women during the period 1961-1995, especially in men and at chronically sun-exposed skin sites. Patients with SCC are also at increased risk of developing new primary cancers, especially in the skin, squamous cell epithelium, hematopoietic tissues and respiratory organs. In experimental studies <i>in vivo</i> and <i>in vitro</i> in human skin we observed that repair of UV-induced DNA damage appears to be more efficient in chronically sun-exposed skin despite a less uniform p53 response. Non-sun- exposed skin is more homogeneous with respect to the epidermal p53 response. Keratinocytes in skin exposed frequently to the sun may be prone to react more easily to cytotoxic stress. Two different modalities of photoprotection significantly reduced the amount of DNA damage and the number of p53-positive cells. In addition, we demonstrated that a well-defined system for <i>in vitro</i> culture of explanted skin provides an excellent alternative to <i>in vivo</i> experiments. </p><p>In conclusion, this study has increased our knowledge of SCC epidemiology in Sweden and of the effects of artificial and solar UVR and sunscreens on chronically sun-exposed and non-sun-exposed sites, respectively, of human skin.</p>
268

Att leva med urinläckage : En longitudinell populationsstudie om livskvalitet hos kvinnor och hur de hanterar sitt urinläckage

Hägglund, Doris January 2002 (has links)
<p>Urinary incontinence is a prevalent condition; nevertheless few women seek professional help. One aim of this study was to investigate all women aged 18-70 years in a Swedish community regarding (a) the prevalence rate and risk factors of urine leakage and (b) the quality of life for women with and without urine leakage, for women with stress incontinence versus urge incontinence, and for women with urine leakage who had or had not sought help. A second aim was to study all women aged 18-46 years from the same population four years later regarding (a) the quality of life and natural history of urine leakage, (b) why some women with persistent urine leakage seek help and others do not, and (c) how they deal with their urine leakage.</p><p>Every fourth woman aged 18-70 years was found to have urine leakage. The number of women with urine leakage increased with increasing age, the number of deliveries, the presence of urinary tract infection, and the use of oestrogen substitutions. Women with urine leakage had a lower quality of life in all eight dimensions of the SF-36 as compared with women without urine leakage. Furthermore, in women with urge incontinence the quality of life was lower compared with women with stress incontinence in all dimensions of the SF-36. Women with urine leakage who had sought help had lower quality of life in seven of eight SF-36 dimensions as compared with women with urine leakage who had not sought help.</p><p>At the four-year follow-up the quality of life had deteriorated in five of eight SF-36 dimensions in women aged 18-46 years with persistent urine leakage as compared with women with persistent continence. The mean annual incidence and remission rates of urine leakage were on the same low level (4%). Most women with slight or moderate long-term urine leakage had not sought professional help, largely because they considered their leakage a minor problem. Pelvic floor exercises was the most commonly used management method for all participants.</p>
269

Eating disorders : Prevalence, incidence, and prospective risk factors for eating disorders among young adult women in the general population

Ghaderi, Ata January 2001 (has links)
<p>Eating disorders (ED) constitute a significant source of psychiatric morbidity and are an important public health concern in Western societies. Knowledge about risk factors for ED is crucial for early detection and implementation of preventive interventions. The aim of the present thesis was to examine the prevalence, incidence, correlates, and the risk factors for ED among 1,157 young adult women in the general population. The studies in the thesis used a prospective design with the potential of addressing methodological limitations in earlier research.</p><p>In Study I, conducted in 1997, the lifetime and point prevalence of DSM-IV-based diagnoses of ED was, respectively, 7.85% and 2.59%. Participants with ED reported higher body dissatisfaction, lower perceived social support from the family, and lower self-esteem compared to participants with no ED. In Study II, it was shown that highest relative use of escape-avoidance coping was reported among participants with ED, followed by dieting participants with no ED, and least among those neither dieting nor with ED. In Study III, (i.e., the follow-up in 1999), the point prevalence of ED was 3.15% and the cumulative 2-year first time incidence was .0105 (n=8). The total incidence group (n=34), as compared to the participants with no ED (controls, n=643), reported significantly lower premorbid self-esteem, and perceived social support from the family and higher body dissatisfaction, higher relative use of escape-avoidance coping, and dieting. Furthermore, the incidence group reported a significant increase in body dissatisfaction and relative use of escape-avoidance coping, and a significant decrease in self-esteem as compared to controls from 1997 to 1999. In Study IV, it was shown that the <i>Survey for Eating Disorders</i> is a reliable and valid self-report questionnaire for the screening of ED and case ascertainment. </p><p>In conclusion, it is suggested that premorbid low self-esteem, perceived low social support, high body dissatisfaction, high relative use of escape-avoidance coping, and dieting be regarded as risk factors for a later development of ED among young adult women. It is also proposed that more attention be devoted to these factors both in designing prevention interventions and in refining current treatments. </p>
270

Headache in Schoolchildren : Epidemiology, Pain Comorbidity and Psychosocial Factors

Laurell, Katarina January 2005 (has links)
<p>Headache is the most frequently reported pain in children and is associated with missed schooldays, anxiety, depressive symptoms and various physical symptoms. A secular trend of increasing headache prevalence has been suggested. Few studies have focused on tension-type headache among children from the general population. </p><p>The aims of this thesis were to describe the prevalence, incidence and prognosis of tension-type headache, migraine and overall headache in schoolchildren, to identify medical, psychological and social factors associated with these headache types, and to determine whether the prevalence of headache has increased over the last decades.</p><p>In 1997, 1850 schoolchildren aged 7-15 years from the city of Uppsala participated in a questionnaire study and 1371 (74.1%) responded. Out of these, a randomly selected, stratified sample of 131 children and their parents were interviewed. Three years later, 122 children from the interview sample replied to an identical headache questionnaire.</p><p>Compared with a similar study in 1955, a significantly lower proportion of schoolchildren reported no headache. The prevalence of tension-type headache increased with age and was significantly higher in girls than boys after the age of twelve. Similar age and gender differences were obtained for migraine. A higher proportion of girls reported frequent headache than boys. Children with headache, especially those with migraine, as well as their first-degree relatives suffered from other pains and physical symptoms more frequently than headache-free children and their first-degree relatives. Although the likelihood of experiencing the same headache diagnosis and symptoms at follow-up was high, about one fifth of children with migraine developed tension-type headache and vice versa. Female gender was a predictor of migraine and frequent headache a predictor of overall headache at follow-up. The estimated annual incidence for tension-type headache, migraine and overall headache was 81, 65 and 131 per 1000 children, respectively. </p><p>In conclusion, the results indicate that headache has become increasingly common among schoolchildren over the last decades. Prevention and treatment of headache is particularly important for girls since they have high prevalence of headache, frequent headache episodes and a poor outcome. In children with headache, diagnoses and treatment should be reassessed regularly and other pains should be asked about and treated as well. </p>

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