Normally swallowing occurs completely without effort. Should the act of swallowing for some reason be impaired, it becomes difficult to eat and drink. Dysphagia is the medical term for eating and swallowing disorders. Dysphagia is common in people with dementia, but the prevalence is not yet fully evaluated. The most common cause of death in people with dementia is aspiration pneumonia, which can be caused by dysphagia. In Sweden investigation and treatment of dysphagia are performed by speech and language pathologists (SLPs) but few of them work with dementia care. This study aims to identify the prevalence of dysphagia in people with dementia, living in a nursing home. The screening methods SSA-S and LtL were used to test the swallowing of 38 participants between 68-96 years of age (M = 86 years). To examine the participants’ oral health the risk assessment tool ROAG was used. When tested with the water swallowing test SSA-S 71,1% of the participants showed signs of aspiration, 36,8% had an oral transit time over 5 seconds, measured with LtL and 92% of the participants had an affected oral health, showing one or more symptoms of severity grade 2 according to ROAG. When adding up the results from the two screening tests a total of 86,8% of the participants showed signs of some kind of swallowing difficulty. Correlation analysis did not show any statistically significant correlations between SSA-S, oral transit time, oral health, or age. The present study found that there is a great need for interventions from speech and language pathologists in people with dementia. / Normalt sker sväljning helt utan ansträngning. Skulle sväljningen av någon anledning inte fungera som den ska, blir det svårt att äta och dricka. Den medicinska termen för ät- och sväljsvårigheter är dysfagi. Dysfagi är vanligt hos personer med demens men det är ännu inte helt kartlagt hur vanligt det är. Hos personer med demens är den vanligaste dödsorsaken aspirationspneumoni, vilket kan orsakas av dysfagi. I Sverige är det logopeder som utreder och behandlar dysfagi men det är få som är verksamma inom demensvården. Den här studien syftar till att kartlägga förekomst av dysfagi hos personer med demenssjukdom boende på ett vård- och omsorgsboende. Med screeningmetoderna SSA-S och LtL genomfördes undersökningar av sväljförmågan hos 38 personer mellan 68-96 års ålder (M = 86 år). För att undersöka deltagarnas munhälsa användes riskbedömningsverktyget ROAG. Av deltagarna fick 71,1 % utslag på vattensväljningstestet SSA-S, 36,8 % hade en oral transporttid över 5 sekunder, mätt med LtL och 92 % av deltagarna hade en nedsatt munhälsa med ett eller flera symptom av grad 2 i munhålan, enligt ROAG. Vid sammanräkning av resultaten från de två screeningtesten uppvisade totalt 86,8 % av deltagarna tecken på någon form av sväljsvårighet. Korrelationsberäkningar visade inga statistiskt signifikanta samband mellan resultat på SSA-S, oral transporttid, munhälsa eller ålder. Studien visar på ett stort behov av logopediska insatser hos gruppen personer med demenssjukdom.

Calcific aortic valve disease (CAVD) is one of the most common causes of cardiovascular disease in North America. Mechanical factors have been closely linked to the pathogenesis of CAVD and may contribute to the disease by actively regulating the mechanobiology of valve interstitial cells (VICs). Mechanical forces affect VIC function through interactions between the VIC and the extracellular matrix (ECM). Studies have shown that the transfer of mechanical stimulus during cell-ECM interaction depends on the local material properties at hierarchical length scales encompassing tissue, cell and cytoskeleton. In this thesis, biomechanical tools were developed and applied to investigate hierarchical cell-ECM interactions, using VICs and valve tissue as a model system. Four topics of critical importance to understanding VIC-ECM interactions were studied: focal biomechanical material properties of aortic valve tissue; viscoelastic properties of VICs; transduction of mechanical deformation from the ECM to the cytoskeletal network; and the impact of altered cell-ECM interactions on VIC survival. To measure focal valve tissue properties, a micropipette aspiration (MA) method was implemented and validated. It was found that nonlinear elastic properties of the top layer of a multilayered biomaterial can be estimated by MA by using a pipette with a diameter smaller than the top layer thickness. Using this approach, it was shown that the effective stiffness of the fibrosa layer is greater than that of the ventricularis layer in intact aortic valve leaflets (p<0.01). To characterize the viscoelastic properties of VICs, an inverse FE method of single cell MA was developed and compared with the analytical half-space model. It was found that inherent differences in the half-space and FE models of single cell MA yield different cell viscoelastic material parameters. However, under particular experimental conditions, the parameters estimated by the half-space model are statistically indistinguishable from those predicted by the FE model. To study strain transduction from the ECM to cytoskeleton, an improved texture correlation algorithm and a uniaxial tension release device were developed. It was found that substrate strain fully transfers to the cytoskeletal network via focal adhesions in live VICs under large strain tension release. To study the effects of cell-ECM interactions on VIC survival, two mechanical stimulus systems that can simulate the separate effects of cell contraction and cell monolayer detachment were developed. It was found that cell sheet detachment and disrupted cell-ECM signaling is likely responsible for the apoptosis of VICs grown in culture on thin collagen matrices, leading to calcification. The studies presented in this thesis refine existing biomechanical tools and provide new experimental and analytical tools with which to study cell-ECM interactions. Their application resulted in an improved understanding of hierarchical valve biomechanics, mechanotransduction, and mechanobiology.

Calcific aortic valve disease (CAVD) is one of the most common causes of cardiovascular disease in North America. Mechanical factors have been closely linked to the pathogenesis of CAVD and may contribute to the disease by actively regulating the mechanobiology of valve interstitial cells (VICs). Mechanical forces affect VIC function through interactions between the VIC and the extracellular matrix (ECM). Studies have shown that the transfer of mechanical stimulus during cell-ECM interaction depends on the local material properties at hierarchical length scales encompassing tissue, cell and cytoskeleton. In this thesis, biomechanical tools were developed and applied to investigate hierarchical cell-ECM interactions, using VICs and valve tissue as a model system. Four topics of critical importance to understanding VIC-ECM interactions were studied: focal biomechanical material properties of aortic valve tissue; viscoelastic properties of VICs; transduction of mechanical deformation from the ECM to the cytoskeletal network; and the impact of altered cell-ECM interactions on VIC survival. To measure focal valve tissue properties, a micropipette aspiration (MA) method was implemented and validated. It was found that nonlinear elastic properties of the top layer of a multilayered biomaterial can be estimated by MA by using a pipette with a diameter smaller than the top layer thickness. Using this approach, it was shown that the effective stiffness of the fibrosa layer is greater than that of the ventricularis layer in intact aortic valve leaflets (p<0.01). To characterize the viscoelastic properties of VICs, an inverse FE method of single cell MA was developed and compared with the analytical half-space model. It was found that inherent differences in the half-space and FE models of single cell MA yield different cell viscoelastic material parameters. However, under particular experimental conditions, the parameters estimated by the half-space model are statistically indistinguishable from those predicted by the FE model. To study strain transduction from the ECM to cytoskeleton, an improved texture correlation algorithm and a uniaxial tension release device were developed. It was found that substrate strain fully transfers to the cytoskeletal network via focal adhesions in live VICs under large strain tension release. To study the effects of cell-ECM interactions on VIC survival, two mechanical stimulus systems that can simulate the separate effects of cell contraction and cell monolayer detachment were developed. It was found that cell sheet detachment and disrupted cell-ECM signaling is likely responsible for the apoptosis of VICs grown in culture on thin collagen matrices, leading to calcification. The studies presented in this thesis refine existing biomechanical tools and provide new experimental and analytical tools with which to study cell-ECM interactions. Their application resulted in an improved understanding of hierarchical valve biomechanics, mechanotransduction, and mechanobiology.

Afin d’alléger les moteurs d’avions et diminuer la consommation de carburant, les industriels tendent à rendre plus compact le système de compression de leurs moteurs, qui représente environ 40% de la masse totale. Or, à taux de compression global égal, la réduction du nombre d’étages implique une charge aérodynamique plus élevée par étage. Cela augmente d’autant les risques de décollements sur les aubes et la dégradation des performances. L’aspiration de la couche limite sur les aubages s’est révélée très prometteuse pour supprimer ces décollements néfastes et satisfaire aux besoins de charge aérodynamique élevée. Cependant, l’aspiration modifie fortement la distribution de pression statique à la paroi des aubes, rendant les approches de conception traditionnelles inadaptées. L’objectif de ce travail de thèse est donc de proposer une nouvelle méthode et de nouveaux critères de conception d’aubages fortement chargés, intégrant l’aspiration de la couche limite. Cette méthode repose sur une stratégie d’aspiration en deux étapes. Dans un premier temps, un contrôle passif, par courbure et diffusion, de la position du point de décollement est effectué dans le but de la rendre insensible aux conditions de fonctionnement. Dans un second temps, un contrôle actif par aspiration vise à placer la fente d’aspiration par rapport au point de décollement de manière à minimiser le taux d’aspiration nécessaire au recollement de la couche limite. Afin de mettre en pratique cette stratégie, une technique de dessin d’aubages par prescription de la distribution de courbure de l’extrados et de la variation de section du canal inter-aubes, est ainsi développée. Associée à un outil de pré-dimensionnement rapide ainsi qu’une évaluation des pertes de pression totale incluant la présence d’aspiration, cette méthode permet ainsi de concevoir une grille de stator aspirée subsonique réalisant une déflexion fluide de 60 degrés, pour un nombre de Mach amont de 0,5, correspondant à un facteur de diffusion de 0,73. Cette performance au point nominal est obtenue avec un coefficient de pertes de pression totale de 2,5%, en aspirant 1,1% du débit entrant dans la grille. Ces valeurs peuvent néanmoins être réduites respectivement à 2,1% et 0,8% par l’emploi d’une fente d’aspiration à bords arrondis. Cette étude numérique bidimensionnelle est effectuée à l’aide du code de calcul elsA de l’ONERA. Afin de valider expérimentalement cette méthode de conception ainsi que les outils numériques associés, une grille d’aubes plane est construite et testée à basse vitesse au laboratoire de Mécanique de Fluides et d’Acoustique de l’Ecole Centrale de Lyon. A mi-envergure, les résultats issus de l’expérience et de simulations numériques 3D confirment la pertinence de la stratégie d’aspiration et la démarche de conception adoptée. Cette confrontation met alors en évidence l’impact de la distribution du taux d’aspiration suivant l’envergure sur l’efficacité de l’aspiration. Etant donné l’importance des écoulements tridimensionnels rencontrés, une généralisation en trois dimensions de la stratégie d’aspiration est proposée et est appliquée numériquement sur cette même grille d’aubes. En contrôlant simultanément les couches limites se développant sur l’aube et sur les parois latérales du canal de compression, il est alors possible de supprimer presque totalement les décollements de coins présents dans celui-ci. En contrepartie, le taux d’aspiration voit sa valeur augmenter très fortement, tempérant ce bénéfice. L’épaisseur des couches limites entrantes se révèle alors également être un facteur déterminant pour le succès du contrôle des couches limites par aspiration, dans un cadre tridimensionnel. / In order to reduce the mass of aircraft jet engines as well as their fuel consumption, manufacturers tend to make the compression system of their engines more compact, since this component represents approximately 40% of the total mass. However, for a given overall pressure ratio, decreasing the number of stages implies increasing the aerodynamic load per stage. This all the more increases the risk of flow separation on the blades ultimately resulting in a decrease in performance. Boundary layer suction on the blade has proven to be very promising to suppress this deleterious flow separation and meet the needs of high aerodynamic loads. Nevertheless, boundary layer suction significantly modifies the static pressure distribution on the blades, making traditional design approaches unsuitable. Therefore, the objective of this Ph.D. work is to develop a new method and new criteria for the design of highly loaded compressor blades, integrating boundary layer suction into the design process. This design method relies on a two-step aspiration strategy. First, passive control of the separation point location is applied via curvature and diffusion in order to make it insensitive to operating conditions. Second, active control through boundary layer suction aims at placing the suction slot with respect to the separation point location, in order to minimize the necessary suction mass flow rate required to reattach the flow. To put this strategy into practice, a blading technique that consists of prescribing the curvature distribution on the suction side of the blade and the cross-section distribution of the blade passage is developed. In association with a fast pre-design tool, as well as an overall total pressure loss coefficient including aspiration, this method allows the design of a subsonic aspirated stator cascade with flow turning of 60 degrees, for an inlet Mach number of 0.5,giving a Diffusion Factor of 0.73. This performance at the design point is obtained for an overall total pressure loss coefficient of 2.5%, aspirating 1.1% of the inlet mass flow rate. Nevertheless, these two values can be respectively reduced to 2.1% and 0.8% by rounding the edges of the suction slot. This bi-dimensional numerical study has been carried out with the elsA solver from ONERA. To experimentally validate this design method and the associated numerical tools, a planar cascade is built and tested at low speed at the Laboratoire de Mécanique de Fluides et d’Acoustique at the Ecole Centrale de Lyon. At mid-span, results from the experiment and from tri-dimensional numerical simulations confirm the relevance of the design approach. This comparison then discloses the impact of the suction mass flow rate distribution along the span, on the efficiency of aspiration. Given the importance of tri-dimensional flows encountered in the experiment and simulations, a generalization in three dimensions of the aspiration strategy is proposed and numerically applied on the same cascade. By simultaneously controlling the boundary layers developing on the blades and on the endwalls,it is possible to almost entirely suppress the corner separations present in the blade passage. However, one disadvantage is that the suction mass flow rate undergoes a strong increase, moderating this benefit. The thickness of the inlet boundary layers appears to be also a key factor in the success of boundary layer control by aspiration, in a tri-dimensional context.

The presented dissertation thesis is focused on the optimization of filtering circuit synthesis. In the five main sections of this work, the author analyzes partial problems related to several areas within the synthesis of modern filtering circuits. The first chapter constitutes an examination of elementary aspects which characterize present-day integrated circuits in voltage feedback operational amplifiers, and this main content is further complemented with a view on possible application of these circuits for the designing of filtering circuits as proposed within subsequent parts of the thesis. In this context, the second chapter contains a description of the design and optimization of digitally controlled universal filters tunable by means of digital potentiometers originally produced for audio technology. These digitally controlled circuits are increasingly utilized as analog preprocessing blocks in digital signal processing systems. The most extensive portion of the dissertation is dedicated to a complex analysis of individual configurations of economical, purposely lossy active function blocks and modern voltage operational amplifiers. This part of the thesis aims at providing a detailed insight into the characteristics of individual configurations of examined circuits; furthermore, in this respect, the author proposes a comparison of various application possibilities relating to these circuits and their wider use in the field of active frequency filters optimization. The described section of the work also includes a definition and examples of application of the designed and realized program, which facilitates significant simplification of purposely lossy ARC filters. In the penultimate part of the dissertation thesis, the design, development, and verification of a suitable synthesis procedure are presented together with the optimization of data and (in particular) power models of EMC filters. Based on the verification of characteristics inherent with the designed models of EMC filters, the suggested measuring procedure related to these filters is described, including the design of a station for measuring elementary parameters of line anti-interference devices up to very high frequencies. In the last section of the thesis, the author discusses the procedure of air ions concentration measurement through an aspiration condenser and analyzes the systematic and random errors as well as the optimization of filtration characteristics of the applied measurement method. This part includes the description of the design and characteristics of the realized fully automated measurement system with an aspiration condenser.

Les masses kystiques latérales du cou (MKLC) bénignes et malignes sont difficiles à différencier cliniquement. L’utilité des modalités d’imagerie et de prélèvement doit être clarifiée. Une revue rétrospective de cas entre 2010 et 2016. Les données d’imagerie ont été récoltées et plusieurs variables propres à la masse furent analysées. Les rapports de cytoponction à l’aiguille fine (CAAF), de la biopsie au trocart (BT) et des examens extemporanés (EE) ont été analysés. La sensibilité, la spécificité, la valeur prédictive positive (VPP) et la valeur prédictive négative (VPN) pour prédire la malignité ont été calculées pour toutes les variables comparées entre les masses kystiques bénignes et malignes. Aucune variable d’imagerie n’a pu différencier les masses kystiques bénignes de malignes. La sensibilité de la CAAF est plus basse que celle de la BT (59% vs 83%; p=0.036) et de l’EE (59% vs 93%; p=0.01). L’EE a une meilleure VPN que la CAAF (92% vs 40%; p<0.001) et que la BT (92% vs 50%; p=0.062). La VPP et la spécificité étaient similaires dans tous les groupes. Les cliniciens ne peuvent pas se fier uniquement à l’imagerie pour différencier les masses bénignes des masses malignes. Vu sa VPP adéquate (92%), la CAAF devrait être utilisée initialement pour tous les patients avec une MKLC. Si la CAAF s’avère négative, la BT devrait être utilisée vu sa meilleure sensibilité. Un examen extemporané devrait toujours suivre une BT négative vu la faible VPN de la BT. Un résultat positif à l’une des trois modalités de prélèvement indique la présence de malignité. / Benign and malignant lateral cystic neck masses (LCNM) are difficult to distinguish clinically. The usefulness of imaging and sampling modalities in clarifying the diagnosis remains unclear. Retrospective review of cases between 2010 and 2016. Imaging data was reviewed and the variables pertaining to the mass were assessed including the following: size, nodal level, fat stranding, extracapsular spread, calcifications, vascularity, necrosis and standardized uptake value. Sampling reports of fine-needle aspiration (FNA), core-needle biopsy (CNB) and frozen section (FS) were also assessed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for predicting malignancy were calculated for all variables and compared between benign and malignant cystic neck masses. Ultrasound was used in 47.2% and CT-Scan in 90.5% of patients. No variables on imaging could definitely differentiate benign from malignant LCNM. FNA had a lower sensitivity then CNB (59% vs 83%; p=0.036) and FS (59% vs 93%; p=0.01). FS had a better NPV when compared to FNA (92% vs 40%; p<0.001) and CNB (92% vs 50%; p=0.062). Specificities and PPV were similar among all groups. Clinicians cannot rely on imaging to differentiate benign from malignant LCNM. Given its adequate PPV (92%), FNA should be used initially on lateral cystic neck masses. Because of its high sensitivity, CNB should be considered if FNA is not diagnostic of malignancy. FS should always follow a CNB not indicative of malignancy, because of the low NPV. Any result diagnostic of malignancy on either FNA, CNB or FS strongly indicates presence of malignancy.

Indiana University-Purdue University Indianapolis (IUPUI) / Gastric residual volume (GRV) is a clinical assessment to evaluate gastric emptying and enteral feeding tolerance. Factors such as the tube size, tube material, tube port configuration, placement of the tube in the gastric fluid, the amount of fluid and person completing the assessment may influence the accuracy of residual volume assessment. Little attention has been paid to assessing the accuracy of GRV measurement when the actual volume being aspirated is known, and no studies have compared the accuracy in obtaining RV using the three different techniques reported in the literature that are used to obtain aspirate in practice (syringe, suction, and gravity drainage). This in vitro study evaluated three different methods for aspirating feeding formula through two different tube sizes (10 Fr [small] and 18 Fr [large]), tube materials (polyvinyl chloride and polyurethane), using four levels of nursing experience (student, novice, experienced and expert) blinded to the five fixed fluid volumes of feeding formula in a simulated stomach, to determine if the RV can be accurately obtained. The study design consisted of a 3x2x2x4x5 completely randomized factorial ANOVA (with a total of 240 cells) and 479 RV assessments were made by the four nurse participants. All three methods (syringe, suction and gravity) used to aspirate RV did not perform substantially well in aspirating fluid, and on average, the methods were able to aspirate about 50% of the volume available. The syringe and suction techniques were comparable and produced higher proportions of RVs, although the interrater reliability of RV assessment was better with the syringe method. The gravity technique generally performed poorly. Overall, the polyvinyl chloride material and smaller tubes were associated with higher RV assessments. RV assessment is a variable assessment and the three methods did not perform well in this in vitro study. These findings should be further explored and confirmed using larger samples. This knowledge will be important in establishing the best technique for assessing RV to maximize EN delivery in practice and will contribute to future research to test strategies to optimize EN intake in critically ill patients.

Indiana University-Purdue University Indianapolis (IUPUI)

Ce mémoire est une étude de cas sur une francophonie locale et sur la réinterprétation de l’imaginaire d’une communauté francophone. Nous nous sommes basés sur le cas de la Bulgarie et de sa communauté bulgare francophone. Nous avons alors questionné la réinterprétation de l’imaginaire communautaire bulgare francophone depuis 1989. Pour répondre à cette interrogation, nous avons analysé les programmes scolaires du Ministère de l’Éducation bulgare pour l’apprentissage du Français Langue Étrangère, les manuels scolaires utilisés dans les lycées bilingues bulgares francophones. Puis, nous nous sommes entretenus avec des personnalités politiques, diplomatiques et professeurs de français en Bulgarie. Nos résultats soutiennent que l’imaginaire communautaire bulgare francophone a été réinterprété selon deux logiques. D’abord, dans une volonté d’européaniser la langue française et le Bulgare francophone, c’est-à-dire, d’interpréter le français comme langue de l’Europe, et former ensuite un individu européen plurilingue. La seconde logique consiste à déployer l’imaginaire bulgare francophone et la langue française en Bulgarie vers d’autres francophonies locales à défaut d’une vision seulement francocentrée. Ces deux aspirations ont été soutenues par des francophonistes – des individus qui ont re-pensé les représentations de la langue française et la définition de la francophonie bulgare. Ces francophonistes ont été placés dans diverses institutions en Bulgarie, notamment au sein de l’Association des professeurs de et en français de Bulgarie. En parallèle des actions de ces individus, d’autres structures et individus en place ont soutenu ou modéré ces deux aspirations – maintenant alors parfois le francocentrisme au sein de l’imaginaire bulgare francophone. / This paper is a case study of a local francophonie and the reinterpretation of the imaginary of a Francophone community. We focused on the case of Bulgaria and its Bulgarian francophone community. Then we questioned the reinterpretation of the imaginary of the Bulgarian French-speaking community since 1989. To answer this question, we analysed the Bulgarian Ministry of Education's curricula for learning French as a foreign language and the textbooks used in bilingual French-speaking Bulgarian high schools. We also interviewed leading Bulgarian politicians, francophone diplomats and French teachers. Our results show that the Bulgarian francophone community imaginary has been reinterpreted according to two logics. On the one hand, into a desire to Europeanise the French language and French-speaking Bulgarian, meaning, to interpret French as the language of Europe, and then to form a plurilingual European individual. The second aim is to extend the French-speaking Bulgarian imaginary and the French language in Bulgaria to other local francophonies, rather than having only a francocentric vision. These two aspirations have been supported by francophonists - individuals who have rethought the representations of the French language and the definition of the Bulgarian francophonie. These francophonists were placed in various institutions in Bulgaria, notably within the Association des Professeurs de et en français de Bulgarie. Alongside the actions of these individuals, other structures and individuals in place have supported or moderated these two aspirations - sometimes maintaining Francocentrism within the Bulgarian Francophone imaginary.

Приведены показатели анализа и обоснование необходимости вдувания в горн заранее нагретого пылеугольного горючего и оксидов железа – аспирационной пыли. Использование именно этого железорудного сырья обосновано желанием утилизировать отходы газоочистки на разных этапах производства и экономией на подготовке сырья. Определён эффект этих действий на показатели доменной плавки при изменениях дутьевых режимов работы печи главным образом на расход кокса и производительность печи. / The analysis indicators and justification for the need to inject preheated pulverized coal fuel and iron oxides - aspiration dust - into the furnace are given. The use of this particular iron ore raw material is justified by the desire to utilize gas purification waste at different stages of production and to save on the preparation of raw materials. The effect of these actions on the performance of blast furnace smelting with changes in the blast operating conditions of the furnace was determined, mainly on coke consumption and furnace productivity.