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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.
61

The Incidence of Clinically Diagnosed Versus Research-Identified Autism in Olmsted County, Minnesota, 1976-1997: Results From a Retrospective, Population-Based Study

Barbaresi, William J., Colligan, Robert C., Weaver, Amy L., Katusic, Slavica K. 01 March 2009 (has links)
Autism prevalence studies have often relied on administrative prevalence or clinical diagnosis as case-identification strategies. We report the incidence of clinical diagnoses of autism spectrum disorders (ASD), versus research-identified autism among residents of Olmsted County, Minnesota, age =21 years, from 1976-1997. The incidence of clinically diagnosed ASD (with 95% CI) was 1.5 per 100,000 (0.0-3.7) in 1980-1983 and 33.1 (22.8-43.3) in 1995-1997, a 22.1-fold increase. In contrast, the incidence of research-identified autism increased from 5.5 (1.4-9.5) per 100,000 to 44.9 (32.9-56.9), an 8.2-fold increase. Only 46.8% of research-identified cases received a clinical diagnosis of ASD. These findings demonstrate the potential for misleading interpretation of results from epidemiologic studies that rely on clinical diagnosis of autism to identify cases.
62

Dilemmas in Measuring and Using Pressure Ulcer Prevalence and Incidence: An International Consensus

Baharestani, Mona M., Black, Joyce M., Carville, Keryln, Clark, Michael, Cuddigan, Janet E., Dealey, Carol, Defloor, Tom, Harding, Keith G., Lahmann, Nils A., Lubbers, Maarten J., Lyder, Courtney H., Ohura, Takehiko, Orsted, Heather L., Reger, Steve I., Romanelli, Marco, Sanada, Hiromi 01 April 2009 (has links)
Pressure ulcer prevalence and incidence data are increasingly being used as indicators of quality of care and the efficacy of pressure ulcer prevention protocols. In some health care systems, the occurrence of pressure ulcers is also being linked to reimbursement. The wider use of these epidemiological analyses necessitates that all those involved in pressure ulcer care and prevention have a clear understanding of the definitions and implications of prevalence and incidence rates. In addition, an appreciation of the potential difficulties in conducting prevalence and incidence studies and the possible explanations for differences between studies are important. An international group of experts has worked to produce a consensus document that aims to delineate and discuss the important issues involved, and to provide guidance on approaches to conducting and interpreting pressure ulcer prevalence and incidence studies. The group's main findings are summarised in this paper.
63

A Gender Sensitive Fiscal Incidence Analysis for Latin America: Brazil, Colombia, the Dominican Republic, Mexico, and Uruguay

January 2019 (has links)
archives@tulane.edu / This dissertation examines how fiscal policy affects gender inequality using a comparable and comprehensive framework and data from Brazil, Colombia, the Dominican Republic, Mexico, and Uruguay. Using the harmonized household microdata provided by the Commitment to Equity (CEQ) Institute at Tulane University, this study assesses how fiscal policy in these countries affects households and beneficiaries with gender equity as the focus. This is the first cross-country comprehensive gendered fiscal incidence analysis evaluating the impact of direct and indirect taxes (including consumption taxes and subsidies), direct and indirect subsidies (e.g., cash transfers), and in-kind education and health transfers combined. The study reveals that male breadwinner households are more disadvantaged pre and post government intervention as compared to female breadwinner households. However, female headed households are more disadvantaged than male headed households. In fact, female headed households are the most severely disadvantaged group compared to any other gender variable. In all countries analyzed in this study, fiscal policy as a whole does improve the wellbeing of those who are more disadvantaged pre fisc (i.e., the poor, defined as those who earn less than US$5.50 PPP per day) regardless of their gender. Further research is needed to determine why female breadwinners are better off than male breadwinners, but female headed households are more disadvantaged than any other type of gender household classification. Additionally, more research should be done to determine the most effective gender variables necessary to assess fiscal policy. / 1 / Samantha Greenspun
64

Evaluation of Nematode Control Practices on Cotton Growth and Yield in Nematode Infested Soils, and the Effect of Bacterial Inoculation Timing on Bacterial Blight Incidence and Cotton Yield

Wilson, Bradley Reagan 10 August 2018 (has links)
Cotton (Gossypium hirsutum) growth, development, and yield can be limited due to reniform nematode and bacterial blight infestation. Studies were conducted in 2016 and 2017 to evaluate the profitability of a soil fumigant application, seed treatments, and inurrow nematicides to protect cotton from nematode infestation as well as inoculation of bacterial blight at various growth stages in cotton to determine effects on yield. Research was conducted by applying various combinations of nematicides to cottonseed at planting and a fumigant prior to planting. Bacterial blight was conducted by inoculated on cotton at multiple growth stages throughout the year. Based on the results of these studies, a seed treatment plus inurrow application should be applied at planting in nematode infested fields to increase yield and economic returns in cotton. Bacterial blight infestation was greatest when inoculated at pinhead square in cotton.
65

Cavity Ring-Down Spectroscopy of Liquid Samples Using Standard Cuvettes at Normal Incidence

Culbertson, Bryan James 12 May 2012 (has links)
Cavity ring-down (CRD) spectroscopy has emerged as a sensitive analytical technique. In this method, a laser pulse is injected through one of two highly-reflective mirrors which form a stable optical cavity and the rate that the light leaves the cavity is monitored by a detector placed behind the second mirror. In this research a CRD spectrometer has been designed and constructed. The light exiting the cavity is collected via a fiber optic cable which is then directed toward a photo multiplier tube (PMT) detector. The signal is digitized and averaged by an oscilloscope and the data are transferred by an I 488 interface to a personal computer where the data are analyzed. Instrument command and data acquisition are controlled by a Visual Basic computer program. A short review of several attempts to measure liquid samples using CRD spectroscopy is presented; most discuss the necessity for the incorporation of Brewster’s angle at the liquid interface. This study integrates a 1 cm standard quartz cuvette at normal incidence. It was determined that there are significant losses from scattering and reflection; however, these losses were not so large as to negate the efficacy of the technique. The hypothesis tested here is that the light “lost” as reflections are collected by the cavity mirrors and redirected back into the cavity. Rhodamine 6G was used as the primary model absorber in these studies. Absorbance measurements were extracted from the measured ring-down times and a detection limit was obtained. Four cavity lengths were constructed to determine the effect on the scattering losses with varying cavity lengths. The calculated detection limit for the CRD spectrometer used in this study was found to be in the range of 4-5 nM. It was found that the detection limit of the CRD spectrometer was 36 times lower than that of the commercial instrument. Aligning the cavity mirrors at longer cavity lengths proved to be more difficult; however, there were no significant additional losses observed by incorporating longer cavities.
66

Skills for exceptional adult life (SEAL): transition to adulthood of youths with disabilities

Boynton, Jessica Marie 25 August 2023 (has links)
The Federal law mandates that free appropriate public education is available to eligible children with disabilities throughout the United States through the Individuals with Disabilities Education Act (IDEA). It ensures that special education and related services are provided in the least restrictive environment. A transition plan is also required to be established for all students with an Individualized Education Program (IEP) before they turn 16. For students with high-incidence disabilities, the transition plan focuses primarily on academic access and accommodations and successful movement into postsecondary education. Other postsecondary areas also include competitive employment, independent living, and community participation. However, students with high-incidence disabilities continue to exhibit poor postsecondary outcomes compared to their peers despite having the potential to be successful and receiving the current level of support available. These youths need help in functional performance areas such as life skills which are not addressed in the school-based setting and significantly impact the transition to adulthood from an employment and independence perspective. Studies have also shown that students with disabilities continue to have significantly less involvement than their peers in areas related to employment, independent living, and community inclusion. Occupational therapy practitioners (OTPs) have the skills and knowledge that may contribute to improved postsecondary outcomes for these students, yet the majority of school-based OTs do not work with transition age-youth or address goals related to transition planning. The role of occupational therapy in the transition team is not well-defined and limited by the guidelines of the Individuals with Disabilities Education Act (IDEA) and significantly decreases as the youths in the high-incidence category get older and closer to graduating from high school. Furthermore, there is the misconception that OTPs are limited to being providers of adaptive equipment, handwriting/fine motor activities, or sensory integration. Following a literature review of the potential role of occupational therapy in transition, this paper proposes a model for an OT-led community-based intervention transition program focusing on life skills training. Skills for Exceptional Adult Life (SEAL) is an interprofessional collaboration program designed for high-incidence youths with developmental disabilities who do not receive comprehensive interventions that address life skills, vocational skills, and self-perceived confidence. According to the Occupational Therapy Practice Framework: Domain and Practice, 4th edition (AOTA, 2020), areas of occupation include activities of daily living, instrumental activities of daily living, rest and sleep, education, work, play, leisure, and social participation.
67

Apport d'une étude de cohorte pour mesurer l'incidence des tumeurs malignes rares : application concernant les sarcomes en région Rhône-Alpes / Contribution of a cohort study to assess the incidence of rare malignant tumors : application to the study of sarcomas in the Rhône-Alpes region

Ducimetière, Françoise 17 December 2009 (has links)
Les sarcomes sont des tumeurs malignes rares, représentant 1% de tous les cancers mais regroupant un large spectre d’entités histopathologiques distinctes. Du fait de leur rareté et de leur difficulté diagnostique, l’épidémiologie des sarcomes reste mal connue. Nous avons décrit l’incidence et la répartition géographique des sarcomes en région Rhône-Alpes grâce à la constitution d’une cohorte prospective et exhaustive de tous les cas incidents en 2005 et 2006, après relecture centralisée systématique des diagnostics par un pathologiste référent. Nous rapportons : - un taux d’incidence brut de 6,2 cas/100 000/an, supérieur à celui publié dans la littérature et confirmé sur les deux années de recueil de données ; - une répartition géographique et une épidémiologie spécifiques selon les sous-types histologiques ; - des discordances de diagnostic portant sur 45% des cas dont 19% de discordances majeures. Nos résultats sont différents des données publiées portant sur des séries rétrospectives ou incomplètes. Ils contribuent à une meilleure connaissance de l’épidémiologie des sarcomes. Ils permettent de poser des hypothèses étiopathogéniques dans la répartition géographique observée notamment pour les tumeurs stromales gastro intestinales et les liposarcomes / Sarcoma is a rare malignant tumour accounting for 1% of all cancers but comprising a wide range of distinct histopathological types. Given the rarity of cases and the difficulty of diagnosis, the epidemiology of sarcomas is still unclear. We have examined the incidence and the geographical distribution of sarcomas based on the results of a prospective cohort study of all incident cases diagnosed in 2005 and 2006 in the Rhône-Alpes region and after centralized and systematic review of diagnosis by a referent pathologist. We report: - a crude incidence rate of 6.2 cases/100 000/year confirmed on these two years of data collection, higher than the one published in the literature ; - a geographical distribution and epidemiology characteristic of each different histological sub-type ; - diagnostic discordances in 45% of cases, of which 19% were major discordances. Our findings, which differ from data published in retrospective or incomplete series, contribute to a better knowledge of the epidemiology of sarcoma. They make it possible to formulate etiopathogenic hypotheses regarding the geographical distribution of the disease, especially for gastrointestinal stromal tumours and liposarcomas
68

Aspects épidémiologiques et caractérisation moléculaire des souches du virus de l’hépatite E (VHE) au Burkina Faso / EPIDEMIOLOGICAL AND MOLECULAR CHARACTERIZATION OF HEPATITIS E VIRUS (HEV) STRAINS IN BURKINA FASO

Traoré, Kuan Abdoulaye 02 June 2015 (has links)
Le virus de l’hépatite E (VHE) est l’agent causal d’une partie des hépatites aigues ou fulminantes qui surviennent essentiellement dans les pays en voie de développement (Afrique, Asie) ou le VHE de génotype 1 semble présenter un profil endémique ponctué de bouffées épidémiques souvent liées à des déplacements de populations (catastrophe climatique ou conflits) (Lui et al., 2013). Récemment il a été montré que ce virus était largement distribué dans des réservoirs animaux (génotype 3 et 4) et la cause d’un grand nombre d’infections zoonotiques aussi bien dans les pays du nord que du sud. Dans la plupart des cas, il s'agit d'une infection spontanément résolutive avec une clairance virale rapide, mais il peut évoluer vers des formes plus sévères avec un niveau de mortalité variant de 1 à 4% dans la population générale et à près de 20% chez la femme enceinte lors des flambées épidémiques (OMS, 2014). Au Burkina Faso, très peu de données existent sur la prévalence chez l’homme, l'épidémiologie moléculaire du VHE ou la présence de ce virus dans le réservoir animal principal que constituent les porcs. De plus, l’ignorance de la population quant aux causes de cette infection d’origine alimentaire, est un facteur de risque qu’on ne peut pas ignorer. L’objectif de ce travail est donc d’améliorer notre connaissance sur cet agent des hépatites. La première partie de notre étude s’est consacrée à l’évaluation de la séroprévalence du VHE chez les donneurs de sang et les femmes venant en consultation prénatale à Ouagadougou. Au total plus de 1700 échantillons de sérums de volontaires ont été collectés dans les banques de sang et centres médicaux: entre 2010 et 2012, sur les 178 donneurs de sang et 189 femmes enceintes testés, 19,1% [IC95, 13,3-24,9%] et 11,6% [IC95, 7,1-16,2%] étaient respectivement positifs aux IgG anti-VHE. Ces taux élevés sont peut-être associé au faible statut socioéconomique et à l’absence de réseaux d’assainissement des eaux (Traoré et al., 2012). En 2014, 3,19% [IC95, 1,70-4,68%] des 533 donneurs de sang testé sont positifs pour des IgM anti-VHE. Ces résultats montrent un risque résiduel transfusionnel non négligeable associé à une transmission à bas bruit et confirme l’intérêt d’identifier la ou les sources de ce virus. La seconde partie de ce travail a été de vérifier le rôle d’une source zoonotique des infections à VHE, via l’évaluation du VHE (par sérologie et typage moléculaire après PCR) dans le réservoir potentiel que sont les porcs et la population à risques exposé à ce réservoir (bouchers et éleveurs). Pour cela nous avons réalisé un recensement des sites de ventes de porcs et évalué la consommation d’animaux. Un taux de séroprévalence de 76% [IC95, 67,6-84,4%] a été mesuré dans une cohorte de 100 bouchers de Ouagadougou avec un facteur de risque de séropositivité 3 fois plus élevé par rapport à la population générale (OR = 3,46 [95%CI 2,85 – 4,21] p <0.001). Les IgG anti-VHE chez les porcs abattus ont été estimés à 80% IC95 [72-87%]. Cette forte prévalence confirme une circulation silencieuse du VHE dans l’élevage porcin au Burkina Faso comme en témoigne l'échantillon positif de foie pour l’ARN VHE qui soutient fermement le risque de zoonose. L’analyse des séquences des produits de PCR des foies de porcs positifs pour VHE a révélé la présence de VHE génotype 3 et 99,8 % d'homologie avec les souches Yaounde et Madagascar. En conclusion, notre étude, la première caractérisation moléculaire des souches du VHE au Burkina, montre la présence de souches VHE génotype 3 dans des régions ou seul le génotype 1 avait été identifié jusqu’alors (Tchad, Maroc). L’évaluation du risque transfusionnel associé nécessite des études complémentaires afin d’évaluer le bénéfice/coût de l'ajout de dépistage du VHE dans les examens de routines des banques de sang, afin de garantir la sécurité du receveur de sang. / The hepatitis E virus (HEV) is causative agent several acute or fulminant hepatitis which mainly occur in developing countries where HEV genotype 1 or 2 appears to have a endemic profile punctuated with epidemic outbreaks (Africa, Asia) (Lui et al., 2013). Genotype 3 and 4 distributed widely in animal reservoirs, were the cause many zoonotic infection in northern and southern countries. In most cases, it is a self-limited infection with rapid viral clearance, but it can evolve into more severe forms with a mortality level ranging from 1 to 4% in the general population to nearly 20% in pregnancy during outbreaks (WHO, 2014). In Burkina Faso, very little epidemiological data are available on HEV. The objective of this work is to improve our understanding of this agent hepatitis. The first part of our study was devoted to the evaluation HEV seroprevalence among blood donors and women attending antenatal care in Ouagadougou. In total more than 1,700 volunteers serum samples were collected in blood banks and medical centers in Burkina Faso. Between 2010 and 2012 on 178 blood donors and 189 pregnant women tested, 19.1% [CI95, 13.3-24.9%] and 11.6% [CI95, 7.1-16.2%], were respectively positive for anti-HEV IgG. These high rates in the general population may be associated a low income and the poor hygienic status (Traoré et al., 2012). In 2014, 3.19% [CI95, 1.70-4.68%] on 525 blood donors tested, were positive for anti-HEV IgM. These results indicate a residual risk for transfusion, probably associated with silent infections and confirm the importance to identify the sources of the virus. The second part of this work was 1) to assess HEV infection among humans in Burkina Faso by exploring the HEV seroprevalence in a high risk population, i.e., butchers; 2) to explore a possible pig-to-human zoonotic transmission cycle by assessing the HEV seroprevalence in slaughter swine; and 3) to identify the genotype of HEV circulating in pigs. The global HEV prevalence among Ouagadougou butchers was estimated to 76%, CI95 [67, 63–84.37%] with a significant risk factor, 3 times higher compared with the general population (OR = 3.46 [95%CI 2.85 - 4.21] p <0.001). IgG anti-HEV in pigs older than 6 months of age were estimated at 80% CI95 [72-87%]. This high prevalence confirms the presence and active circulation HEV among domestic pigs in Burkina Faso as evidenced by the positive sample of liver for HEV RNA which strongly supports the risk of zoonosis. Phylogenetic analyses revealed that genotype 3 HEV is circulating among swine population in Burkina. A similarity >98% was found between swHEV-BF from Yaounde and Madagascar. This data showed for the first time the role of swine in introduction of new HEV in African population. In conclusion, these results latter sign a persistent introduction of HEV infection in the population and hence deserved to be taken in account in transfusion associated risk. Further assessments of the transfusion risk associated require an evaluation of the cost/benefit ratio for the addition of routine HEV RNA screening to the panel of tests on donated blood, to guarantee transfusion safety for the recipient.
69

Diffraction d’atomes rapides sur surfaces : des résonances de piégeage à la dynamique de croissance par épitaxie / fast atom diffraction on surfaces : from bound states resonances to the dynamics of epitaxial growth

Debiossac, Maxime 13 November 2014 (has links)
Ce travail est consacré à l’étude de la diffraction d’atomes rapides (d’énergie cinétiquede l’ordre du keV) en incidence rasante (angles d’incidence ~ 1°) le long ou proche d’unedirection principale d’une surface cristalline. Cette géométrie en incidence rasante permet de(i) récolter, en quelques secondes, la totalité du cliché de diffraction sur un détecteur sensible enposition ; (ii) préserver la cohérence de l’onde de matière en réduisant les sources de décohérencecomme l’excitation électronique et l’agitation thermique. La grande sensibilité des atomes àla forme de la densité électronique de surface (partie répulsive) et au puits attractif de Vander Waals révèle les résonances de Fano et démontre que l’atome voyage, piégé au-dessus de lasurface, de façon cohérente, sur une distance de 0.2μm. Il est également montré que la diffractiond’atomes rapides est une technique robuste pour suivre la dynamique de croissance de semiconducteurs(GaAs) par épitaxie (reconstructions, transitions de phase). Enfin, l’observationde la diffraction sur une feuille de graphène déposé sur 6H-SiC(0001) suggère l’utilisation desatomes rapides comme outil de diagnostic pour le suivi et la caractérisation en temps réel dela croissance du graphène dont les propriétés exceptionnelles dépendent beaucoup des défautsde surface. / This work was devoted to the study of fast atom diffraction (energies in the keV range)at grazing incidence angles (~ 1°) along or close to a low indexed direction of crystalline surfaces.This specific scattering geometry bears two advantages : (i) the diffraction pattern as a wholeis collected within seconds on a position sensitive detector ; (ii) the low energy associated to themotion normal to the surface quenches decoherence due to electronic excitations and stronglyreduces decoherence due to thermal vibrations. The high sensitivity of probe atoms to thesurface electron density (repulsive part) and to the Van der Waals attractive well reveals Fanoresonances where the trapped atoms preserve their coherence over distances as long as 0.2μm.As a complement to these fundamental studies, fast atom diffraction has been proved to be arobust mean to probe the dynamics of epitaxial growth of semiconductors (GaAs). Finally, workperformed on monolayer graphene grown on 6H-SiC(0001) suggest the possibility to use fastatoms to monitor graphene growth in real time, a key process to measure the level of alterationof the intrinsic graphene electronic structure.
70

Matice s prvky -1, 1, 0 / Matrices with Entries -1, 1, 0

Píšová, Vendula January 2019 (has links)
In this thesis we introduce selected classes of matrices, whose entries are only numbers −1, 1, 0. We combine existing results from various fields of Mathematics and enrich them with specific examples and explanations, with the aim of making the understanding of the text easier. Thanks to that, the reader can comprehend the theory and look under the hood of non-trivial applications. We will start with introducing adjacency matrices and covering of complete graphs with complete bipartite graphs. Then we follow with Hadamard matrices and will show the conditions for their constructions. Incidence matrices of the set systems will help us solve the combinatorial problem of the Odd-town clubs. Finally, we will prove the Cayley formula about the spanning trees of the complete graph, using incidence matrices.

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