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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.
71

Zeolites as key-components for electronics and biomedicine / Zéolithes comme composants clés pour l'électronique et la biomédecine

Lülf, Henning 13 December 2013 (has links)
La thèse intitulée « Zeolites as key-components for electronics and biomedicine » traite de travaux sur des cristaux de zéolite-L avec des tailles et des formes différentes pour des applications dans les domaines de l’électronique et de la biomédecine. Il a été montré que, lorsque les monocouches de zéolites-L sont munies d’un biofilm, elles peuvent être utilisées comme des substrats pour une croissance de longue durée de neurones primaires. De plus, les pores des zéolites peuvent être remplies d’un spécial semi-conducteur organique, pour permettre un transport d’électrons à travers les canaux et, plus important, ces matériaux présentent une très haute magnétorésistance en y appliquant un champ magnétique externe. Enfin, les monocristaux de zéolites-L peuvent être utilisés en tant que plateforme pour un oligo-nucléotide multifonctionnel et l’administration d’un médicament-modèle à l’intérieur de cellules vivantes. Les oligo-nucléotides sont attachés aux particules de la surface externe et le médicament modèle est encapsulé dans les pores. Ces premières expériences-modèles confirment que ces systèmes offrent un grand potentiel dans le domaine de la thérapie génique. En résumé, cette thèse montre que les cristaux de zéolites-L peuvent être appliqués avec succès dans des domaines très variés, de l’électronique à la biomédecine. / The aim of this thesis titled “Zeolites as key-components for electronics and biomedicine” is the synthesis, functionalization and applications of zeolite-L particles for applications in electronics and biomedicine. This thesis is organized into 8 chapters, starting in chapter 1 with giving a general overview about nanotechnology and biomedicine. After that the concept of using nanocontainer in biomedicine are briefly discussed. In the following the nanocontainer zeolite-L is introduced and a summary of zeolite- L for applications in nanomedicine is given. Finally, the self-assembly of zeolites in monolayers and their further functionalization is discussed. Chapter 2 describes the zeolite-L synthesis, functionalization and their assembly into functional materials in detail. Three different types of zeolite-L have been used in this thesis: Nanozeolite-L particles with a size of just a few tenths of nanometers, disc-shaped zeolite-L with a diameter of around 200 nm and micrometer sized crystals with a length of about 1000 nm. Then different methods to functionalize the crystals with the desired groups and to obtain specific properties of the crystals are reported. In detail, the exchange with different counter cations, the insertion of guest molecules and the functionalization of the external crystal surface are reported. Finally the assembly into monolayers and their further functionalization by soft lithography is discussed. [...]
72

Integração de dados e processos disponíveis em portais web baseada em ontologias de domínio / Web portal data and processes integration based on domain ontologies

Mello, Marília Terra de January 2008 (has links)
A integração e a troca de informação na Web é uma necessidade reconhecida no mundo atual nos mais diversos domínios de aplicação. A Web constitui hoje o principal meio de acesso a informações, disponibilizando várias formas de acesso a esse conteúdo. No entanto, disponibilizar essa informação de forma integrada para o usuário ainda é um desafio. O Serviço Web Semântico é uma tecnologia de Inteligência Artificial promissora a qual pode contribuir significativamente com o processo de integração tanto de dados como de processos disponíveis em portais Web. O objetivo do presente trabalho é realizar a integração das diferentes funcionalidades oferecidas por portais disponibilizados na Web, fazendo uso de ontologias de domínio através de Serviços Web Semânticos. Para alcançar o objetivo proposto, um sistema de busca e integração, denominado W-KIS, foi projetado e desenvolvido, fornecendo uma visão unificada e transparente ao usuário de toda informação disponível em um determinado número de portais Web, contextualizados a um domínio de aplicação específico. Dois domínios de aplicação foram explorados neste trabalho através de dois estudos de caso: a Biomedicina e a Geologia, cada um fornecendo sua própria ontologia de domínio. Serviços Web Semânticos foram desenvolvidos para encapsular portais Web em ambos os domínios, permitindo ao sistema realizar a integração em cada domínio, separadamente. A aplicação proposta foi validada através da avaliação de sua atuação em ambos os domínios, além de testes com usuários finais e comparações com outras abordagens para integração na Web e motores de busca tradicionais. Através da utilização de Serviços Web Semânticos, W-KIS é capaz de localizar e executar os serviços de forma automática, além de lidar com a heterogeneidade semântica entre as fontes de informação por meio das ontologias de domínio. Desta forma, o sistema fornece apenas informação contextualizada ao interesse do usuário. / Integration and exchange of information across the Internet is a universally recognized need, in a wide variety of domains. Nowadays, the Web is the main source of information, providing many ways to access this content. However, making this information available to the user in an integrated way is still a challenge. New promising application fields such as Semantic Web Services can improve the integration process of data and processes available in Web portals. The goal of the present research is to accomplish the integration of the different functionalities offered by portals available in the Web, making use of domain ontologies through Semantic Web Services. In order to achieve the proposed goal, a search and integration system, named W-KIS, was designed and developed. The system provides the user with a unified and transparent view of the whole information available in a number of Web portals, related to a specific application domain. Two application domains were explored in this work through two case studies: the Biomedicine and the Geology, each one providing its own domain ontology. Semantic Web Services were designed to encapsulate Web portals in both domains, allowing the system to accomplish the integration in each domain, separately. The application proposed in this project was validated through the evaluation of its behavior in both domains, besides other tests with final users and comparisons with other approaches for integration in the Web, and traditional search engines. Making use of Semantic Web Services, W-KIS is able to find and execute the services in an automatic way, besides dealing with the semantic heterogeneity in the information sources by means of domain ontologies. This way, the system provides the user with information contextualized to its interest.
73

Aux frontières de la biomédecine : médecine et professionnels de la douleur / The boundaries of biomedicine : medicine and professional pain

Petit, Audrey 05 December 2014 (has links)
À travers une démarche ethnographique et interactionniste (Blumer, 1969), l’enjeu de cette recherche est de rendre compte de la place occupée par la médecine de la douleur dans la division du travail médical (Hughes, 1996). Ainsi, il s’agit de comprendre pour quelles raisons, quarante années après l’introduction de ce domaine de pratiques en France, les professionnels de la médecine de la douleur rencontrent toujours des difficultés à faire reconnaître leur statut et continuent d’œuvrer pour leur reconnaissance. Trois voies d’entrées sont privilégiées pour répondre à ce questionnement. 1) À travers l’observation des consultations d’évaluation et de traitement de la douleur chronique et l’« activité transversale » des « équipes mobiles douleur » dans des centres de la douleur parisiens, nous rendons compte d’une activité médicale qui ne s’inscrit pas dans le sillage de la biomédecine (Cambrosio et Keating, 2003) et qui est constituée autour de la pluridisciplinarité, d’une approche dite « globale » du patient et d’un attachement aux dimensions psychologiques. Les moyens d’actions thérapeutiques à disposition des médecines ne permettent pas de soulager totalement les patients. Aussi, une grande partie du travail des médecins de la douleur consiste à apprendre aux patients à vivre avec leur douleur ; 2) Les entretiens (biographiques) réalisés auprès des professionnels de la médecine de la douleur -aux trajectoires particulières et provenant de disciplines variées- permettent de retracer des carrières (Hughes, 1996) peu valorisées en lien avec l‘histoire de ce domaine de pratiques ; 3) L’attention portée aux actions collectives entreprises en vue de la reconnaissance de ce domaine de pratiques et du statut de ces professionnels (Abbott, 1988; Le Bianic et Vion, 2008) permet de signifier l’existence de deux répertoires d’action aux logiques différentes et aux effets incertains. Ces voies d’entrée nous permettent de retracer la logique d’évolution de cette activité en partant d’une histoire des tâches et des problèmes et de revenir de manière critique sur le caractère non linéaire du processus de professionnalisation. Cette recherche contribue en outre à mettre en exergue les interstices laissés vacants par la biomédecine tels que le soin et le fait de prendre son temps et donc par là même ce que la médecine de la douleur essaie de combler. De manière plus large, il interroge la forme prise par la médecine contemporaine (Baszanger et al., 2002). / Through an ethnographic and interactionist approach (Blumer, 1969), the aim of this research is to held position’s pain medicine in the division of medical labour (Hughes, 1996). Thus, it seeks to understand why, forty years after the introduction of this “domaine de pratiques” in France, the medical professionals of pain still continue to struggle for the recognition of their status. Three topics are used to answer these questions. 1) Through the observation of consultations dedicated to assessment and treatment of chronic pain and "cross-cutting activity" of "mobile pain teams" in Parisian pain clinics, I describe a medical activity that not in line with biomedicine (Cambrosio and Keating, 2003) and is built on a multidisciplinary, so-called "global" approach of the patient and attached to the psychological dimensions. The means of therapeutic action available medicines fail to completely relieve pain. The main task of doctors of pain is to teach patients to live with their pain; 2) Biographical interviews with medical professionals pain –coming from particular trajectories and from different disciplines- can trace careers (Hughes, 1996a) not valued in relation to the history of this “domaine de pratiques”; 3) The focus on collective actions for the recognition of this “domaine de pratiques” and the status of these professionals (Abbott, 1988b; The Bianic and Vion, 2008) enables us to identify the existence of two repertoires of action characterized by different logics and uncertain effects. These questions allow us to draw the evolution of this activity on the basis of a history of tasks and problems and get back critically on the nonlinear nature of the process of professionalization. This research also helps to highlight the gaps left vacant by biomedicine that the pain medicine is precisely trying to fill, such as care and taking your time. More broadly, it questions the form taken by contemporary medicine (Baszanger et al., 2002).
74

Lawrence Joseph Henderson: Bridging Laboratory and Social Life

Munoz, Mateo Jasmine 04 June 2016 (has links)
This study uses the professional trajectory of the Harvard-trained physical chemist and physiologist Lawrence Joseph Henderson to show how the nascent and highly mobile interconnections between biomedicine and social theory began to crystallize around the concept of the social system in the middle decades of the twentieth century. The social system became a powerful and persuasive way of relating vastly different concepts and their consequences, e.g., the laboratory and social life. By focusing on L.J. Henderson and the social system, this study brings the history of biomedicine into dialogue with the history of the social sciences in a new and interesting way by offering an alternative (pre-cybernetics) genealogy of systems theory. This dissertation is an examination of Henderson's cross-disciplinary application of the concept of the social system in three domains: the social sciences, medicine, and industry. Henderson is a historically interesting case because he allows us a unique point of view--the ability to see border crossings between the social sciences and the life sciences in more than one domain. I argue that the transformation of social theory in inter-war America should be understood as part of a broader set of mid-twentieth century developments in the life sciences in general, and human physiology in particular. / History of Science
75

Moving beyond Resistance and Medicalization: Challenging Common Representations of Bareback Sex and HIV through Ethnography

Brisson, Julien January 2015 (has links)
Condomless sex between gay men, also known as bareback sex, has been a popular object of research since the beginning of the AIDS epidemic. One of the most common perspectives on studying bareback sex has been through a medicalization approach, as it may be observed notably with public health and psychology. In other instances, the abandonment of condom use is framed as an intentional act of resistance to public health. Through the methodological approach of ethnography, I studied how young gay men in their twenties from Toronto understand bareback sex in relations to popular discourses of the sexual practice. While my informants initially had a certain way of talking of bareback sex, their narratives on the sexual practice changed with time and challenged the common representations of bareback sex as either a site of resistance or medicalization, which I argue was possible because of the methodological approach of ethnography. During fieldwork, other themes also emerged in regards to shaping understandings of bareback sex and HIV as it relates to young gay men, such as the traumatic memories of an older generation who witnessed the earlier days of the AIDS epidemic. From this anthropological research, I seek to invite the opportunity to rethink the relationship between sex, biomedical science, and HIV.
76

Autobiographical Accounts of Early-Onset Alzheimer's Disease: Obituaries of the Living Dead?

Stanley, Daina January 2013 (has links)
The thesis was designed to gain insight into how Alzheimer’s disease influences selfhood from first-personal accounts of illness. The focus of the study was narrowed further by concentrating on the autobiographies of individuals diagnosed with Early-Onset Alzheimer’s disease (EOAD). The purpose of this thesis was to analyze the autobiographies of individuals with EOAD with the aim of understanding their selfhood. In this thesis I argue that, Alzheimer’s disease may influence a change in self, however, the self is not lost entirely. This thesis draws on the philosophical conception of narrated self as it allows for one perpetually constructed self, whereby a change in self does not necessarily mean the self is lost entirely. Through an interpretive analysis of six autobiographical accounts of Alzheimer’s, this thesis demonstrates that Alzheimer’s disease influences a loss of sense of self but that autobiography enables individuals with Alzheimer’s to (re)construct self.
77

Repetitive climbing effect on muscle activation

Pettersson, Victor January 2020 (has links)
Background. Climbing is growing as a recreational sport worldwide. Climbing is a physically demanding sport requiring well developed strength and endurance. Plenty of studies have been made in the area of climbing in order to understand how the body adapts, which muscles are being used and how to prevent injury. A lot of these studies uses electromyography (EMG), a tool that measures electrical currents in muscles to detect muscle activity, as measurement method in order to do findings within the area. Aim. The aim was to study differences in muscle activation in arm and leg muscles in climbers before and after 40 repeated attempts over two weeks on a boulder problem. Furthermore, correlation between climbing level and change in total measured muscle activation after repeated attempts was assessed. Methods. 15 participants (five women and ten men) participated in this study. Standardized electrode placements and maximal voluntary isometric contractions (MVIC) were made for muscles; Flexor Carpi Radialis (FCR), Bicep Brachii (BB), Rectus Femoris (RF) and Gastrocnemius Lateralis (GL) before each measurement in order to maintain good reliability. Participants repeated a specific climbing route, adapted to the participants climbing ability, 40 times, divided into four sessions over two weeks. Before the first measured attempt the participant got to practice the route twice to get familiar with the moves. Average muscle activation was calculated by dividing the total muscle activation from each muscle with the time it took to complete the climbing route. Peak muscle values were calculated by dividing the highest muscle activation value with the MVIC values to get a %MVIC value. Results. A decrease in average muscle activation for FCR and BB were found (p=0.038, 0.023) whereas an increase in average activation for GL was found (p=0.027). Peak muscle activation showed significant decreases regarding upper extremities FCR and BB (p=0.008, p=0.011) but no significant changes to lower extremities RF and GL. Total average muscular activation regarding all muscles combined showed a general decreased activation (p=0.001). Moderate correlation was found between red-point level and decrease in total average muscle activation (r=0.53). Conclusion. When repeating a climbing route, the climbers muscle activation differs in upper and lower extremities, with a decrease in upper extremities peak and average muscle values, and an increase in GL average muscle values. Repetitions improves technique and muscle memory which could be the reason for the overall decrease in total muscle activation. Hopefully, this study could enrich the climbing world with further knowledge in how to train for climbing.
78

Rovnováha s Adderallem: Responzibilizační diskurzy na online fóru / Finding Balance with Adderall: Responsibilization Discourses in Online Fora

Benešovská, Barbora January 2021 (has links)
This thesis explores the discourses that surround psychopharmacological stimulant use in the online forum on reddit.com. The focus is on the negotiations of variable effects that people ascribe to the medication use. In the collective search for explanations and remedies, individuals become responsible for different aspects of their life in order to reach a balanced state. This state is constantly at flux and dependent on many variables, that are to be taken under control. Users thus have to monitor themselves and acquire self-knowledge, that is a based on listening to their embodied experience, and they have to adjust their bodies and daily routines. The idea of finding the right balance, that is informed by the embodied experiences, is closely connected to the ancient humoralist forms of governmentality. However, unlike in ancient humoralism, where balance necessarily meant adapting to the environment, biotechnologies have expanded the horizon of posssible modulations of bodies and selves, that may be achieved by the individuals themselves.
79

The Effects of Longer Stage Durations During an Incremental Graded Exercise Test on the Finnish Lactate Threshold Concept / The Effects of Longer Stage Durations During an Incremental Graded Exercise Test on the Finnish Lactate Threshold Concept

von Martens, Julius January 2021 (has links)
Background: The end-product of glycolysis is lactate, which is subsequently oxidised to produce more energy. With increasing intensity, the rate of lactate production exceeds the capacity to eliminate lactate, leading to an exponential accumulation of blood lactate. Clinicians use incremental graded exercise tests to induce this blood lactate curve. Two distinct thresholds can then be determined from the curve, of which the second threshold is highly correlated with competitive endurance performance. The exact threshold intensities depend on the threshold concept used as well as on variations in the test protocol. Aim: To evaluate how the Finnish lactate threshold concept is affected by using stage durations of 5 minutes instead of the recommended 3, and to determine how this affects the maximal oxygen uptake. Methods: Seven well-trained adults were recruited to perform two separate incremental graded exercise tests with 3- and 5-minute stages, respectively. Lactate thresholds were determined directly by blood lactate measurements and according to the instructions of the Finnish Society of Sport Sciences. Breath-by-breath gas exchange was measured throughout the tests.  Results: No significant differences occurred at the first lactate threshold. At the second lactate threshold, heart rate, oxygen uptake and blood lactate remained unchanged, while speed dropped (-0.81 ±0.81 km/h; p=0.037) when comparing the 5-minute protocol with the 3-minute protocol. Both protocols resulted in similar peak oxygen uptakes, while speed at peak oxygen uptake decreased (-1.07 ±0.89 km/h; p=0.015) for the 5-minute protocol. Conclusion: This study showed that the chosen stage duration does not affect the blood lactate at the first or second lactate threshold, while a longer stage duration does affect the work intensity corresponding to the second lactate threshold of the Finnish lactate threshold concept. As the work intensity at LT2 is often used to prescribe endurance training and to predict competitive endurance performance, these findings can be of interest to the endurance testing community. It enables an extended understanding when designing test protocols and when analysing the results of a lactate threshold test. This might in turn contribute to more accurate exercise intensity prescriptions and thereby faster development among endurance athletes. Further research with more subjects as well as research into the validity of the Finnish lactate threshold concept is recommended. / Bakgrund: Vid glykolys bildas laktat som biprodukt som sedan oxideras för att producera mera energi. Vid högre träningsintensitet produceras mer laktat i kroppen än kroppen hinner oxidera och därmed börjar laktat ackumuleras i blodet. Kliniskt används inkrementella träningstester för att framkalla en blodlaktatkurva. Vanligtvis bestäms två distinkta trösklar ur kurvan, av vilka den andra laktattröskeln är starkt korrelerad med uthållighetsprestation i tävlingssammanhang. Den exakta träningsintensiteten vid trösklarna beror på metoden som använts för att bestämma trösklarna ur blodlaktatkurvan samt variationer i testprotokollet. Syfte: Att bedöma hur den finska metoden för att bestämma laktattrösklarna påverkas då ett testprotokoll med 5-minutersnivåer används istället för de rekommenderade 3-minutersnivåerna, samt att bedöma hur detta påverkar den maximala syreupptagningsförmågan. Metoder: Sju vältränade vuxna utförde två separata inkrementella träningstester, med 3-minuters- respektive 5-minutersnivåer. Laktattrösklarna bestämdes med hjälp av blodlaktatmätningar och enligt instruktionerna av the Finnish Society of Sport Sciences. Försökspersonernas gasutbyte loggades under hela testernas gång.  Resultat: Inga signifikanta skillnader fanns vid första laktattröskeln. Vid den andra laktattröskeln var puls, syreupptagning och laktatnivå samma för båda protokollen, medan löphastigheten var lägre (-0.81 ±0.81 km/h; p=0.037) för 5-minutersprotokollet jämfört med 3-minutersprotokollet. Båda protokollen resulterade i liknande maximalt syreupptag, men löphastigheten vid maximalt syreupptag var lägre (-1.07 ±0.89 km/h; p=0.015) vid 5-minutersprotokollet.  Slutsatser: Studien visade att nivåernas varaktighet inte påverkade laktatvärdet vid första eller andra laktattröskeln, men att en längre nivålängd påverkar arbetsintensiteten vid den andra laktattröskeln då den finska metoden för att bestämma trösklarna används. Eftersom arbetsintensiteten vid den andra laktattröskeln ofta används för att förutse uthållighetsprestation i tävlingssammanhang samt för att ordinera arbetsintensitet för uthållighetsträning kan studien bidra med en värdefull förståelse för individer som jobbar med uthållighetstester. De kan utnyttja denna förståelse både då de utvecklar testprotokoll och då de analyserar resultat från tröskeltester. I längden kan detta leda till noggrannare ordineringar vad gäller arbetsintensitet och därmed en snabbare utveckling bland uthållighetsidrottare. Ytterligare forskning med fler försökspersoner samt forskning för att validera den finska metoden för att bestämma laktattrösklar behövs.
80

Využití mobilního telefonu k analýze tekutých vzorků / Use of cell phone in liquids analysis

Křístek, Tomáš January 2016 (has links)
Technological development, broad availability and ubiquity of mobile phones made it possible in recent years to start a progression leading to the integration of mobile phones into biomedical analytical methods, the development of telemedicine and mobile personal health applications. This paper deals with the literature review of the mobile phone usage in biomedicine, with emphasis on the methods of optical analysis and technical solutions using 3D printing technology. It provides a draft and practical implementation of salivary cortiol level measuring system using a mobile phone, ELISA analytical methods, 3D printing technology and a set of custom Matlab functions connected with Matlab Mobile application and Mathworks Cloud. Also provides critical evaluation of results and method possibilities, and presents set of proposals and findings for quality of measurment optimization.

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