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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.
31

(Central) Auditory Processing Disorders: A Hearing Loss of the Brain

Elangovan, Saravanan 05 August 2016 (has links)
No description available.
32

A Hybrid Pixel Detector ASIC with Energy Binning for Real-Time, Spectroscopic Dose Measurements

Wong, Winnie January 2012 (has links)
Hybrid pixel detectors have been demonstrated to provide excellent quality detection of ionising photon radiation, particularly in X-ray imaging. Recently, there has been interest in developing a hybrid pixel detector specifically for photon dosimetry. This thesis is on the design, implementation, and preliminary characterisation of the Dosepix readout chip. Dosepix has 256 square pixels of 220 mm side-length, constituting 12.4 mm2 of photo-sensitive area per detector. The combination of multiple pixels provides many parallel processors with limited input flux, resulting in a radiation dose monitor which can continuously record data and provide a real-time report on personal dose equivalent. Energy measurements are obtained by measuring the time over threshold of each photon and a state machine in the pixel sorts the detected photon event into appropriate energy bins. Each pixel contains 16 digital thresholds with 16 registers to store the associated energy bins. Preliminary measurements of Dosepix chips bump bonded to silicon sensors show very promising results. The pixel has a frontend noise of 120 e-. In low power mode, each chip consumes 15 mW, permitting its use in a portable, battery-powered system. Direct time over threshold output from the hybrid pixel detector assembly reveal distinctive photo-peaks correctly identifying the nature of incident photons, and verification measurements indicate that the pixel binning state machines accurately categorise charge spectra. Personal dose equivalent reconstruction using this data has a flat response for a large range of photon energies and personal dose equivalent rates.
33

Logistik vid begränsat utrymme : Jämförelsestudie mellan fyra byggarbetsplatser

Chyad, Yousif, Ali, Khadija January 2019 (has links)
Planning of material handling in limited spaces has become more relevant in the construction industry and since material cannot always be delivered at the right time in the right place, a delay in the flow chain is created. Each construction site has unique conditions and thus different solutions.In this thesis, four workplaces at Peab have been visited and inspected. The purpose of the thesis was to explore the problems that arise with the logistics in a limited space and find solutions that can be implemented on future construction projects.The aim of the study was to find the common factors that exist for the workplaces within a small area and find ways of working that can change the planning and execution of logistics.Surveys to professional workers and interviews with site managers and supervisors contributed with information to the report.After compiling the thesis work, the result shows that there are opportunities to change the working method of the work management to increase efficiency and productivity.In the study, it appears that there is a lack of communication in the workplaces as a large number of workers do not know when the next delivery of material takes place. In addition, the professional workers admit that they did not have a great influence over the business. Recommended solutions that were developed in the study were experience feedback and further development of the APD plan.
34

Dynamic Action Potential Restitution Contributes to Mechanical Restitution in Right Ventricular Myocytes From Pulmonary Hypertensive Rats

Hardy, Matthew E., Pervolaraki, E., Bernus, O., White, E. 23 February 2018 (has links)
yes / We investigated the steepened dynamic action potential duration (APD) restitution of rats with pulmonary artery hypertension (PAH) and right ventricular (RV) failure and tested whether the observed APD restitution properties were responsible for negative mechanical restitution in these myocytes. PAH and RV failure were provoked in male Wistar rats by a single injection of monocrotaline (MCT) and compared with saline-injected animals (CON). Action potentials were recorded from isolated RV myocytes at stimulation frequencies between 1 and 9Hz. Action potential waveforms recorded at 1Hz were used as voltage clamp profiles (action potential clamp) at stimulation frequencies between 1 and 7Hz to evoke rate-dependent currents. Voltage clamp profiles mimicking typical CON and MCT APD restitution were applied and cell shortening simultaneously monitored. Compared with CON myocytes, MCT myocytes were hypertrophied; had less polarized diastolic membrane potentials; had action potentials that were triggered by decreased positive current density and shortened by decreased negative current density; APD was longer and APD restitution steeper. APD90 restitution was unchanged by exposure to the late Na+-channel blocker (5μM) ranolazine or the intracellular Ca2+ buffer BAPTA. Under AP clamp, stimulation frequency-dependent inward currents were smaller inMCTmyocytes and were abolished by BAPTA. In MCT myocytes, increasing stimulation frequency decreased contraction amplitude when depolarization duration was shortened, to mimic APD restitution, but not when depolarization duration was maintained. We present new evidence that the membrane potential of PAH myocytes is less stable than normal myocytes, being more easily perturbed by external currents. These observations can explain increased susceptibility to arrhythmias. We also present novel evidence that negative APD restitution is at least in part responsible for the negative mechanical restitution in PAH myocytes. Thus, our study links electrical restitution remodeling to a defining mechanical characteristic of heart failure, the reduced ability to respond to an increase in demand.
35

La confessionnalisation de l'aide canadienne au développement

Paquette, Francis 12 1900 (has links)
Plusieurs indices permettent de croire que la politique étrangère canadienne ainsi que l’Aide publique au développement (APD) ont été remodelées de manière considérable durant la dernière décennie. Sur plusieurs thèmes, l’arrivée du gouvernement conservateur de Stephen Harper coïncide avec ces changements. Parmi ceux-ci, il semble que certaines Organisations non gouvernementales religieuses (ONGR) en partenariat avec l’Agence canadienne de développement international (ACDI) soient favorisées dans leur financement fédéral. L’objectif de ce mémoire est donc, dans un premier temps, de quantifier cette tendance dans l’allocation des fonds de l’APD. Dans un second temps, il s’agit d’expliquer les raisons ayant initié ce virage du régime de l’APD canadienne. L’hypothèse de recherche est que l’aspect religieux de l’idéologie du cabinet de Stephen Harper constitue un élément fort de la culture stratégique (CS) qui modifie le comportement et les décisions quant à la gestion de son régime de l’APD. Ce mémoire, en utilisant une démarche empirique, démontre que les théories institutionnalistes typiquement utilisées dans les études de l’APD ne permettent pas de saisir adéquatement le phénomène observé. Ce mémoire résout de manière novatrice ce déficit théorique en utilisant le concept de la culture stratégique et les approches constructivistes. / Several indicators suggest that Canadian foreign policy and the Official Development Assistance (ODA) have been remodeled significantly during the last decade. Several of these changes coincide with the arrival of the Conservative government of Stephen Harper. Of these, it seems that some religious non-governmental organizations (RNGO) in partnership with the Canadian International Development Agency (CIDA) are favored in their federal funding. The objective of this thesis is twofold; first, to quantify the trend in the allocation of funds to the RNGO. The second objective is to explain the reasons for this shift in the orientation of Canadian ODA. The research hypothesis is that the religious aspect of the ideology of the Harper cabinet is a strong element of its strategic culture that can influence the behavior and decisions facing the management of its ODA. This thesis, using an empirical approach, shows that institutionalism theories typically used in the studies of ODA do capture adequately the observed phenomenon. This thesis solves in a novel way, this theoretical gap by using the concept of strategic culture and constructivist approaches.
36

Brandskydd under byggtid med BIM : Förbättringsmöjligheter för brandskyddet under byggtid i skedesstyrda APD-planer med BIM

Lundblad Roth, Rebecka, Jerräng Carlstedt, Ludwig January 2018 (has links)
Vid en brand på byggarbetsplatsen finns det risk för personskador, skador på egendom och att byggproduktionen hamnar i ett driftstopp som kan bli kostsamt. Det finns brister vid planeringen av brandskyddet under byggtid (BUB) och vid olika arbetsmoment på byggarbetsplatsen. Planeringen av BUB behöver förbättras utefter hur en byggarbetsplats, och således brandrisker, förändras under byggproduktionen. Ett förslag på hur detta skulle kunna förbättras är att BUB är med i produktionsplaneringen och redovisas på arbetsplatsdispositionsplaner (APD-planer). Arbetsmoment som kan vara en brandrisk borde också planeras tillsammans med BUB för en brandsäkrare byggarbetsplats. Brandskyddsprojektering är idag till stor del inte inkluderat i det digitala arbetssättet som Building Information Modeling (BIM) innebär. Att brandkonsulten inte är med och arbetar i BIM leder till att de fördelar som finns med samverkan mellan olika discipliner inte kan utnyttjas. Den forskning som finns rörande brandskydd i BIM idag fokuserar på projektering av den färdiga byggnaden och hur brandskydd ska kunna inkluderas i BIM. Det finns idag ingen forskning som berör både brandskydd på byggarbetsplatsen och BIM-projektering av byggarbetsplatsen. Detta leder till ett kunskapsglapp mellan BIM som arbetssätt på byggarbetsplatsen och planering av BUB. På grund av de påträffade problemområdena syftade studien till att undersöka förbättringsmöjligheter för brandskyddet under byggtid. Detta genom att kartlägga förutsättningar och tillämpbara områden där BUB kan inkluderas i arbetet med APD-planer och tidsberoende BIM-modeller. Målet med studien var att framta ett underlag till framtida arbetsmetoder där BUB, APD-planer och BIM på byggarbetsplatser används tillsammans. För att uppfylla syftet utfördes en litteraturstudie och en intervjustudie. Litteraturstudien gjordes för att granska publicerat material rörande BUB, byggarbetsplatsplanering med APD-planer samt BIM på byggarbetsplatsen och BIM med hänsyn till brandskydd. Intervjustudien gjordes för att få en inblick i hur personer använder sig av BUB, APD-planer och BIM på byggarbetsplatser (i praktiken). Den information som framkom från teoretisk kunskap och praktiska erfarenheter analyserades för att kartlägga förutsättningar och tillämpbara områden där BUB kan inkluderas i arbetet med APD-planer och tidsberoende BIM-modeller. Detta för att kunna överbrygga gapet som finns mellan BUB, APD-planer och användandet av BIM på byggarbetsplatser. De identifierade områden som framtagits är planering, kommunikation samt kontroll och uppföljning. För att kunna arbeta med BUB och skedesstyrda APD-planer i BIM inom de identifierade områdena finns det krav på vissa grundläggande förutsättningar. För att kunna ta fram APD-planer och göra dessa skedesstyrda i BIM-modellen krävs det utbildning för att få nödvändig kunskap och kompetens hos både projekteringen och produktionen. Det kommer också krävas ett tidigt samarbete mellan produktionen och projekteringen för att täcka alla kompetensområden som behövs vid planering av produktionen av en byggnad med BIM. För att kunna projektera APD-planer i BIM är det även en förutsättning att alla discipliner arbetar i BIM-modellen. Saknas det information, exempelvis landskap, går det inte att göra fullständiga APD-planer över byggområdet i BIM. Att ta fram skedesstyrda APD-planer där BUB inkluderas i en BIM-modell har i denna studie visat sig vara fördelaktigt inom flera områden. Att planera BUB tillsammans med APD-planer ivgör att brandskyddet på byggarbetsplatsen kan planeras med hänsyn till produktionen och att kraven går att genomföra utan att produktionen blir lidande. Med skedesstyrda APD-planer i en BIM-modell blir det möjligt att visualisera förändringarna på byggarbetsplatsen och på så vis även förutspå vilka brandrisker som uppkommer under olika skeden i byggnationen. BUB inkluderat i en BIM-modell kan vara ett verktyg för att förbättra kommunikationen på byggarbetsplatsen. Detta genom att informationen som läggs in blir mer projektspecifik vilket leder till att BUB blir lättare att förmedla, tydligare att följa och mer förståelig. Med bättre information och ökad kunskap om BUB kan kontroll och uppföljning utföras effektivare och därmed förbättra brandskyddet genom att kontrollerna utförs med en högre kvalité. Detta ger förhoppningen om att brandskydd under byggtid blir en större del av planering och projektering av byggarbetsplatsen samt leder till en säkrare byggarbetsplats. / In case of a fire at a construction site there is a risk of personal injury, property damage and stop in the building production that may be costly. There are shortcomings in the planning of fire safety at the construction site and at different construction methods. The planning of fire safety at construction sites are also in need of improvements according to how a construction site, and thus risks of fire, change during construction production. This by planning the fire safety along with the production of the building and that the fire safety is presented on workplace disposition plans. Fire protection design is mostly not included in the digital work method that Building Information Modeling (BIM) implies. The fact that the fire consultant is not involved with and works in BIM means that the benefits of collaboration between different disciplines cannot be utilized. The research on fire protection in BIM today focuses on the design of the completed building and how fire protection can be included in BIM. There is currently no research regarding both fire safety at the construction site and BIM modelling of the construction site. This leads to a gap between BIM as a working method at the construction site and the planning of fire safety. Because of mentioned problem areas, the study’s purpose was to investigate improvements for fire safety on construction sites. This by mapping out conditions and applicable areas where fire safety can be included in the planning of workplace disposition plans in time-dependent BIM models. The aim of the study was to provide a basis for future work methods in which fire safety, workplace disposition plans and BIM at construction sites are used together. To fulfill the purpose, a literature study and an interview study were conducted. The literature study was conducted to review published material regarding fire safety, construction site planning with workplace disposition plans, BIM at the construction site and BIM with fire safety design. Interviews were conducted to gain an insight into how people use fire safety documents, workplace disposition plans and BIM on construction sites (in practice). The information derived from theoretical knowledge and practical experience was analyzed to map the conditions and applicable areas where fire safety can be included in the planning of workplace disposition plans and time-dependent BIM models. This to bridge the gap between fire safety, workplace disposition plans and the use of BIM on construction sites. The identified areas that have been established are planning, communication and control and follow-up. To be able to work with fire safety and workplace disposition plans in time-dependent BIM model within the identified areas, there are some basic conditions that needs to be fulfilled. To be able to develop workplace disposition plans and make these time-dependent in the BIM model, education is needed to get the necessary knowledge and skills in both the design and production. There also needs to be an early collaboration between production and design to cover all areas of expertise needed in planning the production of a building with BIM. To be able to design workplace disposition plans in BIM, it is also a prerequisite that all disciplines work in the BIM model. If there is no information, such as information of the landscape, it is not possible to complete workplace disposition plans over the whole construction site in BIM. To develop time-dependent workplace disposition plans where fire safety are included in a BIM model, this study has proven to be beneficial in several areas. Planning the fire safety together with workplace disposition plans allows the fire protection at the construction site to be planned viregarding production and that the fire safety requirements can be implemented without the production being compromised. Time-dependent workplace disposition plans in a BIM model make it possible to visualize the changes at the construction site, thus predicting fire risks during different stages of the construction. Fire safety included in a BIM model can be a tool for improving communication at the construction site. This is because the information about the fire safety on construction sites inserted becomes more project-specific, which means that the information about the fire safety requirements can be easier to convey, clearer to follow and more understandable. With better information and increased knowledge about fire safety on construction sites, control and follow-up can be performed more effectively and therefore improving the fire safety by performing the controls with a higher quality. This gives the hope that fire protection during construction will be a major part of planning and designing the construction site and that this will lead to a safer construction site.
37

ADRENERGIC STIMULATION IN ACUTE HYPERGLYCEMIA: EFFECTS ON CELLULAR AND TISSUE LEVEL MURINE CARDIAC ELECTROPHYSIOLOGY

Thyagarajan, Sridevi 01 January 2018 (has links)
Cardiovascular complications associated with elevated levels of glucose in the blood (Hyperglycemia, HG) is a growing health concern. HG is known to be associated with a variety of cardiovascular morbidities including higher incidence of electrical disturbances. Although effects of chronic HG have been widely investigated, electrophysiological effects of acute hyperglycemia are relatively less known. Further, hyperglycemic effects on adrenergic response is not widely investigated. We used excised ventricular tissues from mice to record trans-membrane potentials during a variety of pacing protocols to investigate cellular/tissue level electrophysiological effects of acute hyperglycemia and adrenergic stimulation (1µM Isoproterenol, a β-adrenergic agonist). A custom program was used to compute action potential durations (APD), maximal rates of depolarization (dv/dtmax), and action potential amplitudes (APA) from the recorded trans-membrane potentials. From these computed measures, electrical restitution and alternans threshold were quantified. Restitution was quantified using the Standard Protocol (SP; basic cycle length BCL= 200ms), Dynamic Protocol (DP; 200-40ms or until blockade) and a novel diastolic interval (DI) control protocol with Sinusoidal Changes in DI. Results from 6 mice show that acute hyperglycemia causes prolongation of the APD. Effects of adrenergic stimulation during acute hyperglycemia were partially blunted compared with non-hyperglycemic state, i.e. hyperglycemia minimized the decrease in APD that was produced by adrenergic stimulation. Similar, but less consistent (across animals) effects were seen in other electrophysiological parameters such as alternans threshold. These results show that acute hyperglycemia may itself alter cellular level electrophysiology of myocytes and importantly, modify adrenergic response. These results suggest that in addition to long term re-modeling that occurs in diabetes, acute changes in glucose levels also affect electrical function and further may contribute to systemically observed changes in diabetes by blunting adrenergic response. Therefore, further investigation into the electrophysiological effects of acute changes in glucose levels are warranted.
38

Early maladaptive schemas and cognitive distortions in psychopathy and narcissism

Torres, Cristian, Cristian.Torres@act.gov.au January 2003 (has links)
Personality disorders have traditionally been considered refractory to psychological interventions. Two of the most common, and potentially harmful personality disorders are antisocial personality disorder / psychopathy, and narcissism. Although a great deal of conceptual overlap exists between psychopathy and narcissism, the empirical study of these constructs has proceeded largely independently of one another. Further complicating the discrimination of these constructs is the identification of the bi-factorial nature of psychopathy - conceptualised as primary and secondary psychopathy - as well as the identification of two distinct forms of narcissism, overt and covert. The recent resurgence of interest in the sub-clinical manifestations of these two constructs has led to the development of a number of easily administered instruments to measure each of the psychopathy and narcissism constructs, as dimensional traits, within normal populations. This has provided empirically validated and reliable instruments to further explicate these two overlapping constructs. The first of the two studies reported sought to discriminate between psychopathy and narcissism through the recharacterisation of these constructs in terms of the early maladaptive schemas outlined in Young’s early maladaptive schema theory (Young, 1999). Two hundred and ninety one participants completed questionnaires measuring primary and secondary psychopathy, overt and covert narcissism, and early maladaptive schemas. Findings are consistent with the hypothesis that psychopathy and narcissism are discriminable in cognitive-interpersonal terms, as operationalised by early maladaptive schemas. Findings also call into question the earlier observed hierarchical structure of the Young Schema Questionnaire. The current analysis identified a two-factor structure to the schema questionnaire, rather than the previously stated 5-factors. Having demonstrated the usefulness of understanding psychopathy and narcissism in cognitive-interpersonal terms, the second study sought to further clarify the association between psychopathy and narcissism through the reconceptualisation of these constructs in cognitive terms, through the identification of the cognitive distortions operative in each disorder. One hundred and thirty two participants completed a cognitive distortions questionnaire developed by the author, along with the same measures of primary and secondary psychopathy, and overt and covert narcissism, as those administered in study 1. Findings were interpreted as providing support for the notion of psychopathy representing a sub-category of narcissism. Findings also provide further supportive evidence for the validity of the primary / secondary psychopathy, and overt / covert narcissism distinctions. The further clarification of the factor structure of the Young Schema Questionnaire, and the replication of the reliability and construct validity of the measure of cognitive distortions developed for this research are highlighted as areas for future research.
39

Kommunikationsmodell för APD-plan vid användning av materialrutor och gångstråk / Model of communication for a construction site plan when using material zones and walking path

Ahlander, Alfred, Ekroth, Pontus January 2017 (has links)
Syfte: Platsbyggd byggnadsproduktion är en komplicerad process. En tillfällig fabrik, med nya materialupplag och nytt arbetsplatsområde upprättas vid varje enskilt projekt, vilket komplicerar processen ytterligare. Materialhanteringen utgör en stor besparingsmöjlighet i byggnadsprojekt och 40 % av tiden som förloras på en byggarbetsplats kan tillskrivas materialhantering. För att få bukt med slöseri kopplat till materialhantering krävs en väl bearbetad logistikplanering, fungerande kommunikation samt kunskapsbeaktning från tidigare genomförda projekt. Studiens mål är därför att identifiera förbättringsåtgärder gällande användning av materialrutor och gångstråk, samt skapa en kommunikationsmodell för arbetsplatsdispositionsplanen (APD-planen) som stödjer erfarenhetsåterföring. Metod: Studien har utfört fallstudier på två projekt inom NCC:s organisation. Kvalitativ datainsamling i form av litteraturstudie, intervjuer, dokumentanalys och observation har använts. Semistrukturerade intervjuer har utförts och innefattar sju respondenter med olika befattningar inom byggbranschen. Resultat: Studien har tagit fram faktorer som bör beaktas vid planeringen av materialrutor och gångstråk. Vidare visar resultatet att det krävs resurser och strukturerade processer för att erfarenhetsåterföring i byggnadsprojekt skall fungera. För att lyckas med användningen av materialrutor och gångstråk krävs god kommunikation av APD-planen. I studien har även en kommunikationsmodell av APDplanen som stödjer erfarenhetsåterföring tagits fram. Konsekvenser: Det är under inköps- och leveransplaneringen som förutsättningarna för materialrutor och gångstråk sätts, därför bör APD-planen vara mer i fokus under detta skede. En förutsättning för att användningen av materialrutor och gångstråk skall fungera är att det finns resurser som stödjer platsledningen vid planering och utförandet. Genom att använda sig av logistikresurser inom organisationen underlättas planering och hantering av material på byggarbetsplatsen och insamlade erfarenheter kan förmedlas mellan projekt. Ute i produktionen bör det finnas en ansvarig godsmottagare som är extra insatt i APD-planen och materialrutor, genom kontinuerlig kommunikation med platsledning och logistikresurs. Begränsningar: Eftersom arbetet endast omfattar studie av två byggnadsprojekt finns det en begränsning i vilka faktorer och resonemang som lyfts fram. Även om resultatet grundas från två byggnadsprojekt är de grundläggande processerna och händelseförloppen vid uppförande av byggnader likartade och resultatet kan därför tillämpas på liknande byggnadsprojekt. / Purpose: On-site construction is a complicated process. A temporary factory, with new zones for materials and workplace area must be established for each new project, which complicates the process further. Material management stands for a big saving opportunity in building projects and 40 % of the time lost on a construction site can be attributed to material management.  To overcome this waste connected to material management a well-processed logistics planning, god communication as well as experience feedback from previous projects is required. The aim for this thesis is therefore to identify improvement measure regarding the use of material-dedicated buffer zones and walking paths, and as well as create a model of communication that supports experience feedback. Method The thesis is a case study on two projects within the organization of NCC.  A qualitative data collection with literature review, interviews, document analysis and observation has been conducted. Semi-structured interviews have been conducted and includes seven respondents with different position within the construction industry. Findings: The thesis has produced factors that should be taken into consideration when material zones and walking paths are planned. The result shows that resources and structured processes are required if experience feedback should work during the construction project. To succeed with the use of material-dedicated buffer zones and walking paths, good communication of the construction site plan is needed. Furthermore, the thesis has resulted in a model of communication that supports experience feedback.   Implications: It’s during the purchase and delivery planning that the conditions for the material-dedicated buffer zones and walking paths are set, therefore the construction site planning should be involved more in this phase. A prerequisite for using dedicated material zones and walking paths are resources which supports the construction management with planning and performance. By using logistic resources within the organization facilitates planning and management of material at the construction site, enables that collected experience can be conveyed between projects. In the production there should be a responsible receiver of material deliveries, who is extra briefed in the constructions site plan and the material-dedicated buffer zones through continuous communication with the construction management and logistic resource. Limitations: Since the thesis only includes two building projects, there is a limitation of the factors and arguments that are treated. Although the result is based on two building projects the fundamental processes and course of events are similar and can therefore be applied on other building projects.
40

L’impact de la dégradation du signal de parole sur le langage, de sa représentation à sa compréhension / The impact of speech signal degradation on language, from its representation to its comprehension

Dekerle, Marie 14 December 2015 (has links)
L'objectif de cette thèse est de s'intéresser à l'impact de la dégradation du signal de parole sur le traitement et les représentations du langage. Le signal peut être dégradé de façon transitoire (i.e., parole dans le bruit, Axe 1) ou permanente (Axe 2). L'Axe 1 étudie l'impact de la présence de bruit sur le traitement sémantique au niveau du mot isolé et dans un contexte phrastique. Deux études ont permis de mettre en évidence que lorsque le signal de parole est masqué, le traitement sémantique est moins efficace, voire disparait. A la lumière de l'Effortfulness Hypothesis nous suggérons que le traitement sémantique n'est pas automatique mais dépendant de ressources cognitives. Lorsque le signal de parole est dégradé ces ressources cognitives sont allouées aux traitements linguistiques de bas niveau, les traitements de haut niveau comme le traitement sémantique sont donc moins efficaces. L'Axe 2 évalue les liens entre la dégradation permanente du signal de parole du fait d'un manque de maturité des traitements auditifs centraux ou à un Trouble du Traitement Auditif (TTA) et les représentations langagières. Deux études se sont intéressées au développement des traitements auditifs et à la présence de TTA au sein d'une population d'adultes dyslexiques. Les résultats ont mis en évidence que les traitements auditifs centraux continuent leur maturation durant l'adolescence. La dernière étude a permis de mettre en évidence chez la population dyslexique des difficultés dans les tests impliquant des traitements spectral et temporel. Ces compétences sont apparues liées au sein de cette population aux représentations phonologiques. L'ensemble des résultats suggèrent que la dégradation du signal de parole a différents effets sur le langage selon sa nature. Ainsi, lorsqu'elle est transitoire elle impacte sa compréhension en dépit d'une intelligibilité préservée. Une dégradation transitoire impacte la compréhension malgré l'intelligibilité, la dégradation permanente impacte les représentations différemment selon la population / This thesis aims at investigating the effect of speech degradation on language processing and representation. Speech signal can be degraded temporary (i.e., speech in noise) or continually, when central auditory processes are deficient. Experimental work was therefore based on two main axes. The first one got interested in the effect of noise on semantic processing, despite preserved intelligibility. Two studies showed that semantic processing is less efficient when speech is presented in noisy condition. In light of the Effortfulness Hypothesis, we suggest that semantic processing relies on cognitive resources. When signal is degraded these resources are reallocated to low level processes and therefore few are left available to perform higher level processes. Axe 2 aims at evaluating links between continuous speech degradation because of immaturity of central auditory processes or Auditory Processing Disorder (APD) and language representation. Two studies investigated the effect of auditory processing development on language on a children population (6-11 years old) and the effect of APD on language representation in an adult dyslexic population. Both populations were evaluated using the BECAC (Donnadieu et al. 2014). This battery aims at evaluating central auditory processes using non-verbal material so that auditory performances can be related to language competences. Results evidenced that central auditory processes mature until adulthood, and at some point in development (8-9 years old) are linked to language representation. Results of the last study showed that dyslexic adults are impaired in tests involving spectral and temporal processes; in addition these abilities are related with phonological awareness. Altogether, these results indicate that speech degradation has distinct effects on language depending on its nature. Therefore when temporary, speech degradation impacts its comprehension despite intelligibility. When continuous, speech degradation’s impact evolves during development and disappears in normal adults. However, it stays for dyslexics

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