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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.
111

Vysokofrekvenční Identifikace monetárních šoků ve Švédsku / High Frequency Identification of Monetary Policy Shocks in Sweden

Němčík, Erik January 2022 (has links)
Current effectiveness and functioning of one of the key instruments of monetary policy, the interest rate, has been debated around the world with an increasing intensity. Sweden, specifically, characterized by a recent low inflation period coupled with an experimental approach to monetary policy (utilizing both negative interest rates and quantitative easing) presents a peculiar case of interest. This thesis presents new evidence on the monetary policy transmission in Sweden during the low inflation period. To convey this, it utilizes the Proxy-SVAR method, where data from financial markets are used to identify monetary policy shocks and their propagation through the financial and macroeconomic variables. In particular, STINA-swaps are used as an instrumental variable in our main model of interest. The results strongly suggest dampened effectiveness of the repo rate, the Riksbank's main interest rate tool, in achieving the inflation target over the past decades. Price puzzle is present in all model variations applied and hence hints at the inability of the Swedish central bank to effectively control inflation via interest rate decisions. It is important to state that the results are robust to multiple econometric specifications, different inflation setups or estimation methods. Furthermore, the...
112

Integrated Management of Interface Power (IMIP) Framework

Mahkoum, Hicham 12 1900 (has links)
La présence importante de plusieurs réseaux sans-fils de différentes portées a encouragée le développement d’une nouvelle génération d’équipements portables sans-fils avec plusieurs interfaces radio. Ainsi, les utilisateurs peuvent bénéficier d’une large possibilité de connectivité aux réseaux sans-fils (e.g. Wi-Fi [1], WiMAX [2], 3G [3]) disponibles autour. Cependant, la batterie d’un nœud mobile à plusieurs interfaces sera rapidement épuisée et le temps d’utilisation de l’équipement sera réduit aussi. Pour prolonger l’utilisation du mobile les standards, des réseaux sans-fils, on définie (individuellement) plusieurs états (émission, réception, sleep, idle, etc.); quand une interface radio n’est pas en mode émission/réception il est en mode sleep/idle où la consommation est très faible, comparée aux modes émission/réception. Pourtant, en cas d’équipement portable à multi-interfaces radio, l’énergie totale consommée par les interfaces en mode idle est très importante. Autrement, un équipement portable équipé de plusieurs interfaces radio augmente sa capacité de connectivité mais réduit sa longévité d’utilisation. Pour surpasser cet inconvénient on propose une plate-forme, qu'on appelle IMIP (Integrated Management of Interface Power), basée sur l’extension du standard MIH (Media Independent Handover) IEEE 802.21 [4]. IMIP permet une meilleure gestion d’énergie des interfaces radio, d’un équipement mobile à multi-radio, lorsque celles-ci entrent en mode idle. Les expérimentations que nous avons exécutées montrent que l’utilisation de IMIP permet d'économiser jusqu'a 80% de l'énergie consommée en comparaison avec les standards existants. En effet, IMIP permet de prolonger la durée d'utilisation d'équipements à plusieurs interfaces grâce à sa gestion efficace de l'énergie. / The large availability of wireless networks of different ranges, has contributed to the development of new generation of handheld devices with multi-radio interfaces. Thus, the end-users are able to achieve ubiquitous and seamless connectivity across heterogeneous wireless networks (e.g., Wi-Fi [1], WiMAX [2] and 3G_LTE [3]). However, a mobile node with multi-radio interfaces has its battery energy consumed rapidly, which reduces the operation/usage time of the device. To improve battery usage, wireless network standards have defined (individually) different interface states (transmit, receive, idle, sleep, etc.); when an interface is not transmitting or receiving, it goes to sleep/idle state where energy consumption is very low compared to transmit and receive states. However, in the case of multi-radio handheld devices, the total energy consumed by the interfaces in sleep/idle state is significant. Thus, equipping a mobile device with multiple interfaces increases its seamless connectivity but reduces its operation/usage longevity. To overcome this inconvenient, we proposed a framework, called IMIP (Integrated Management of Interface Power) that consists of an extension of MIH (Media Independent Handover) IEEE 802.21 standard [4]. IMIP allows a better power management of radio interfaces of a multi-radio mobile node; indeed, it reduces considerably energy consumption. The basic idea behind IMIP is to shut down any interface in idle mode and use a proxy that emulates the interface; the proxy wakes up the interface when it receives a connection request directed to this interface. IMIP requires at least one interface in active mode. Experiments show that using IMIP enables a saving of up to 80% of power consumption compared with existing power management standards. Thus, IMIP allows longer usage of multiple interface devices thanks to its effective energy management.
113

Integrated Management of Interface Power (IMIP) Framework

Mahkoum, Hicham 12 1900 (has links)
No description available.
114

Ger?ncia de redes de sensores sem fio: uma abordagem com SNMP / Wireless Sensor Network Management an SNMP approach

Cyriaco, Frederico Silveira 06 February 2012 (has links)
Made available in DSpace on 2016-04-04T18:31:32Z (GMT). No. of bitstreams: 1 Frederico Silveira Cyriaco.pdf: 3302714 bytes, checksum: 964c5126f1a1cc104fbe1bb7b7a546d9 (MD5) Previous issue date: 2012-02-06 / This dissertation aims to propose an approach for remote management of wireless sensor networks. For that was inserted in the context of sensor networks the Proxy type element, responsible for interconnect two different networks, while maintaining the ability to communicate between these two networks, as well as the adaptation of communication protocols. In this case, the Proxy networks which interconnects the networks of wireless sensors and IP. The management protocol used on the side of the IP network is SNMP, Single Network Management Protocol, as a network management protocol stable, open source and widely disseminated and used in network environments. In order to combine the functionality via SNMP management with a network of wireless sensors was performed engineering MIB, Management Information Base, creating a correspondence between the characteristics of wireless sensor network configuration and functionality, performance and failure, present in a classical network management. With this MIB was possible to build a prototype as a proof of concept to demonstrate these features. / A presente disserta??o tem como objetivo propor uma abordagem para a ger?ncia remota de redes de sensores sem fio. Para isso, foi inserido no contexto de redes sensores o elemento do tipo Proxy, respons?vel por interconectar duas redes distintas, mantendo a capacidade de comunica??o entre estas duas redes, assim como a adapta??o de protocolos de comunica??o. Neste caso, as redes as quais o Proxy se conecta s?o as redes de sensores sem fio e IP. O protocolo de ger?ncia utilizado do lado da rede IP foi o SNMP, Single Network Management Protocol, por ser um protocolo de ger?ncia de redes est?vel, de c?digo aberto e amplamente utilizado e disseminado em ambientes de rede. Com o objetivo de se combinar as funcionalidades de ger?ncia via SNMP com uma rede de sensores sem fio, foi realizada a engenharia da MIB, Management Information Base, criando-se uma correspond?ncia entre caracter?sticas da rede de sensores sem fio e as funcionalidades de configura??o, desempenho e falha, presentes em uma rede de ger?ncia cl?ssica. Com esta MIB foi poss?vel elaborar um prot?tipo, a t?tulo de prova de conceito, para a demonstra??o destas funcionalidades.
115

Ger?ncia de redes sensores sem fio com SNMP: uma abordagem com proxy gateway / Using SNMP for wireless sensor network management: an approach with a proxy gateway

Madeira, John Franklin Loiola 21 June 2013 (has links)
Made available in DSpace on 2016-04-04T18:31:42Z (GMT). No. of bitstreams: 1 John F L Madeira.pdf: 1208031 bytes, checksum: cacbe507cfeea663dc6feac02f58faa7 (MD5) Previous issue date: 2013-06-21 / This paper presents an approach to management of wireless sensor network (WSN) with the use of the Simple Network Management Protocol (SNMP). In this proposal, was implemented a new element called SNMP Proxy Gateway (SPG) that has aimed to make the interconnection of management without the need for modification or adaptation of the stack TCP/IP protocols. Thus, a new implementation based in hardware and software were deployed to make the transition of SNMP PDUs for WSN. A set of experiments were made in laboratory to test and validate the proposed results. / Este trabalho apresenta uma abordagem para ger?ncia de rede sensores sem fio (RSSF) com utiliza??o do Simple Network Management Protocol (SNMP). Nesta proposta, foi introduzido elemento chamado SNMP Proxy Gateway (SPG) que tem objetivo de fazer a interconex?o das arquiteturas de rede para ger?ncia sem a necessidade de altera??o ou adapta??o da pilha de protocolos TCP/IP. Para isso, foi implementado prot?tipo de ger?ncia da rede atrav?s de um conjunto hardware e software com fun??o de fazer a transcri??o dos PDUs do SNMP para a RSSF. Um conjunto de experimentos foram executados em laborat?rio com objetivo de testar a proposta e validar os resultados obtidos.
116

Proxy IP de baixo custo e m?ltiplos sensores para cidades inteligentes / Proxy IP low cost and multiple sensors to smart cities

Machado, Leandro Filiagi 18 December 2015 (has links)
Made available in DSpace on 2016-04-04T18:31:46Z (GMT). No. of bitstreams: 1 Leandro Filiagi Machado.pdf: 5882687 bytes, checksum: be6f1f6830e339317c23060e0e5453e3 (MD5) Previous issue date: 2015-12-18 / With the advancement of Urban Intelligence and Smart Cities, the importance of remote monitoring and data collection increased. Regarding the monitoring data, the IP Proxy is an important platform for the realization of interconnection between the sensors and the Internet. In recent literature, several gateway architectures for network sensors have been proposed to integrate Wireless Sensor Network (WSN) and Internet. Most WSN gateways implementations retrieve sensor data and display the results to customers via the web. The disadvantage of these solutions is that they use specific protocols to connect the sensors, thereby prohibiting direct interaction between clients and sensor nodes. Optionally, the adoption of sensors for SNMP management has the potential to reduce the complexity of the gateway. For this reason, this paper presents the design and implementation of an open platform and low cost with the use and modification of a non-commercial wireless router with serial connection to communicate with the sensors, which are connected to an Arduino Nano microcontroller. The results showed that applications of the IP Proxy can successfully connect multiple sensors and the Internet, where data can be transmitted all over the world via the Ethernet or WLAN. / Com o avan?o da intelig?ncia Urbana e as Cidades Inteligentes, a import?ncia do monitoramento remoto e coleta de dados aumentou. Em rela??o ao monitoramento de dados, o ProxyIP ? umaplataforma importante para a realiza??oda interconex?o entre os sensores e a Internet. Na literatura recente, v?rias arquiteturas de gateway para sensores de rede t?m sido propostas para integrar Rede de Sensores sem Fio (RSSF) e Internet. A maioria das implementa??es de gateways de RSSF recuperam dados de sensores e exibem os resultados para os clientes via web. A desvantagem dessas solu??es ? que eles usam protocolos espec?ficos para ligar os sensores, proibindo assim a intera??o direta entre clientes e n?s sensores. Como op??o, a ado??o do protocolo SNMP para gerenciamento de sensores tem o potencial para reduzir a complexidade do gateway. Por esta raz?o, este trabalho apresenta a concep??o e implementa??o de uma plataforma aberta e de baixo custo com o uso e modifica??o de um roteador sem fio comercial, com conex?o serial para se comunicar com os sensores, que s?o ligado a um microcontrolador Arduino Nano. Os resultados das aplica??es mostraram que o Proxy IP pode interligar com ?xito multiplos sensores e a Internet, onde os dados podem ser transmitidos em todo o mundo atrav?s da Ethernet ou WLAN.
117

Proposta de um Proxy Manager para a Internet das coisas / Proposal of a Proxy Manager for Internet of things

Oliveira, Rodolfo Francisco de 12 December 2016 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-01-30T13:50:30Z No. of bitstreams: 1 Rodolfo Francisco de Oliveira-0.pdf: 3556902 bytes, checksum: 27f19ccfffa88186c03498b81ac0064f (MD5) / Made available in DSpace on 2017-01-30T13:50:30Z (GMT). No. of bitstreams: 1 Rodolfo Francisco de Oliveira-0.pdf: 3556902 bytes, checksum: 27f19ccfffa88186c03498b81ac0064f (MD5) Previous issue date: 2016-12-12 / Pontif?cia Universidade Cat?lica de Campinas ? PUC Campinas / A new revolution is happening: the Internet of Things, a new wave of technologies where it is possible to connect everyday objects to the Internet. Among these technologies, one of the most criticai is the Wireless Sensor Networks. A Wireless Sensor Network consists of several elements called Sensor Nodes, which collect environmental information such as light, temperature and air quality, providing data to applications on the Internet, usually through an intermediate element called the Gateway. For a Wireless Sensor Network to work properly, it is essential that the elements that make it are managed efficiently. However, there is a shortage of available management solutions, especially when these Wireless Sensor Networks are installed in known environments, such as office buildings, factories, homes and cities. The lack of management tools is one of the main factors that hinder the deployment of Wireless Sensor Networks and consequently the Internet of Things. The purpose of this work is to provide a centralized management platform for Wireless Sensor Networks installed in known environments. Conceptually, this platform is called the Proxy Manager, hosted by the network gateway. The platform is able to communicate with a Network Manager and other applications located on the Internet through web services, receiving management parameters and providing summarized data. The Proxy Manager functionalities are split into two management categories: network infrastructure and application, which in turn are divided into Configuration, Performance and Fault management. In this work, the implemented functionalities relating to the network infrastructure management are: Proxy Manager and Sensor Node configuration; route finding through RSSI (Received Signal Strength Indicator) and number of hops to the Sensor Node; performance monitoring via PER (Packet Error Rate); fault recovery using alternative routes and the generation of alerts to the network administrator. Regarding the application management, the functionality implemented is the sensor configuration, since this will effectively collect the data. Tests of the features implemented were done, involving the establishment of routes, performance monitoring, disaster recovery, data collection and platform performance. The tests showed that the proposed solution is functional. Finally, it is anticipated that this work will contribute to the study and implementation of new management functionalities and Wireless Sensor Networks interconnection. / Uma nova revolu??o est? acontecendo: ? a Internet das Coisas, uma nova onda de tecnologias onde ? poss?vel conectar ? Internet objetos do cotidiano de forma inteligente. Dentre estas, uma das mais cr?ticas s?o as Redes de Sensores sem Fio. Uma Rede de Sensores sem Fio consiste em v?rios elementos denominados N?s Sensores, os quais coletam grandezas do meio ambiente, tais como luz, temperatura e qualidade do ar, disponibilizando as mesmas para aplica??es na Internet, normalmente atrav?s de um elemento intermedi?rio denominado gateway. Para o bom funcionamento de uma Rede de Sensores sem Fio, ? imprescind?vel que os elementos que a comp?em sejam gerenciados de maneira eficiente. No entanto, h? uma escassez de solu??es de ger?ncia dispon?veis, principalmente quando estas s?o voltadas para ambientes previamente conhecidos, como pr?dios comerciais, ind?strias, resid?ncias e cidades. Esta escassez de ferramentas de ger?ncia ? um dos principais fatores que dificultam a implanta??o maci?a de Redes de Sensores sem Fio e, consequentemente, da Internet das Coisas. Sendo assim, a proposta deste trabalho ? apresentar uma plataforma de gerenciamento centralizado para Redes de Sensores sem Fio, instaladas em ambientes conhecidos. Conceitualmente, esta plataforma se denomina Proxy Manager, e ficar? hospedada no gateway da rede. A mesma ? capaz de se comunicar com um Gerente de Rede e outras aplica??es localizadas na Internet atrav?s de web services, recebendo par?metros de ger?ncia e disponibilizando dados sumarizados. As funcionalidades do Proxy Manager s?o divididas em dois focos de ger?ncia: da infraestrutura da rede e da aplica??o, as quais s?o subdivididas nas ?reas de ger?ncia de Configura??o, Desempenho e Falhas. No trabalho em quest?o, as funcionalidades implementadas referentes ? ger?ncia da infraestrutura da rede foram: configura??o do Proxy Manager e dos N?s Sensores; estabelecimento de rotas para os mesmos tendo como base a RSSI (Received Signal Strength Indicator) e o n?mero de saltos para os N?s Sensores; monitoramento de desempenho atrav?s da PER (Packet Error Rate); e recupera??o de falhas, atrav?s do estabelecimento de rotas alternativas e gera??o de alertas para o administrador da rede. Em rela??o ao gerenciamento da aplica??o, a fun??o implementada foi a de configura??o dos sensores, localizados nos N?s Sensores, os quais efetivamente ir?o coletar os dados. Testes relacionados as funcionalidades implementadas, envolvendo o estabelecimento de rotas, monitoramento do desempenho, recupera??o de falhas, coleta de dados pelos sensores e desempenho da plataforma foram realizados, os quais demonstraram que a solu??o em quest?o ? funcional. Por fim, espera-se que o presente trabalho possa contribuir para o estudo e implementa??o de novas funcionalidades de ger?ncia e interconex?o de Redes de Sensores sem Fio, tanto nesta quanto em outras plataformas, atrav?s de trabalhos vindouros.
118

50 000 ans d'histoire de la végétation et du climat en Europe occidentale : étude pollinique et approche multi-proxy sur la séquence sédimentaire du Bergsee (Forêt Noire, Allemagne) / 50 ka of vegetation and climate history in Western Europe : pollen study and multi-proxy approach on the Bergsee lacustrine record (Black Forest, Germany)

Duprat-Oualid, Fanny 11 January 2019 (has links)
Le Bergsee offre une séquence sédimentaire terrestre et continue sur l’histoire environnementale de l’Europe de l’Ouest entre 50 ka BP et aujourd’hui.Un enregistrement pollinique continu et séculaire permet la construction de l’évolution de la végétation et du climat sur la dernière période glaciaire.Outre l’opposition entre le Stade Isotopique Marin 3 et 2 (le second étant plus steppique), la succession de stades et d’interstades courts nord-atlantiques est reflétée par l’alternance de steppes (i.e. climat froid/sec) et de courts épisodes forestiers (i.e. réchauffements). Des phases glaciaires plus prononcées attestent de Stades de Heinrich en Europe de l’Ouest.Ces résultats sont validés par : 1) la confrontation avec des études européennes et 2) l’approche multi-proxy (chironomes, alkanes, géochimie) appliquée à des épisodes clés.Une comparaison avec les données archéologiques montre finalement le potentiel de contribution du contexte climato-environnemental du Bergsee à la compréhension des changements sociétaux du Paléolithique Supérieur. / Bergsee Lake provides a terrestrial and continuous sediment record of environmental changes in Western Europe for the last 50 ka.A continuous pollen record established at secular resolution allow to reconstruct the vegetation and climate variability of the Last Glacial period.Contrasted climate/vegetation is recorded between Marine Isotope Stages 3 and 2 (more steppic for the second one), and the north-Atlantic stadial/interstadial succession is also reflected by alternating steppe (i.e. cold/dry climate) and short forested episodes (i.e. warming). Moreover, Heinrich Stadials are evidenced as pronounced glacial phases by the Bergsee record.These results are supported by 1) comparison with other European records and 2) the multi-proxy approach (chironomids, alkanes, sedimentary data) applied on key climatic periods.Finally, comparison with archaeological data highlights the great potential contribution of the Bergsee record to the understanding of society changes of the Late Palaeolithic.
119

Dynamique holocène du paysage et mobilités des pratiques territoriales au mont Lozère (Massif central, France) : Approche paléoenvironnementale multi-indicateurs à haute résolution spatio-temporelle / Evolución del paisaje holoceno y movilidad de las prácticas humanas en el Mont Lozère (Macizo Central, Francia) : Estudio paleoambiental multi-proxy a alta resolución espaciotemporal

Servera-Vives, Gabriel 12 December 2014 (has links)
Un total de cinq séquences a été étudié sur le Mont Lozère afin de reconstruire la dynamique paysagère et les usages du sol sur la longue durée. L’approche multiproxy utilisé a permis de déterminer les principaux rythmes d’anthropisation et de déterminer son caractère régional et/ou local. Ce travail mené à haute résolution spatiale, chronologique et analytique a permis d’intégrer les résultats avec les données obtenus dans le cadre du PCR-Mont Lozère, afin de caractériser les modes d’occupation de la montagne qui ont modelé ce paysage culturel depuis le Néolithique jusqu’à nos jours. Une longue histoire des interactions socio-environnementales a été mise en évidence au Mont Lozère, avec une première phase à caractère agropastoral dès le Néolithique ancien, vers ca. 4550-4400 cal BC. Le Néolithique final est une période clé caractérisée par un important impact agropastoral fondé sur l’utilisation du feu pour l’ouverture de clairières. Pendant l’Âge du Fer, un déboisement marqué dans les espaces d’altitude et de piedmont coïncide avec un développement des activités agropastorales et métallurgiques. Le Haut Moyen Âge se caractérise par l’amplification des déforestations, contemporaines d’un essor des activités agropastorales. Durant le Moyen Âge Central, un système diversifié d’exploitation des ressources naturelles inclue de la métallurgie, l’agriculture, le pastoralisme, l’extraction minière et le charbonnage. Le développement agropastoral du Bas Moyen Âge aboutit à une déforestation marquée du massif qui s’étend jusqu’à la moitié du 19ème siècle, quand commencent la déprise agropastorale et les reboisements au Mont Lozère. L’histoire de la nardaie qui caractérise les espaces sommitaux suit ces phases majeures de l’anthropisation et dévoile le rôle clé qu’a joué l’agropastoralisme dans la genèse et l’évolution de ce paysage culturel de moyenne montagne. / Five sedimentary sequences have been studied in the Mont Lozère with the aim to reconstruct the landscape dynamics and the land-use through the longue durée. The use of a multi-proxy analysis has allowed us both to identify distinct rhythms of human-induced landscape shift and to establish the local/regional extent of these changes. The use of high spatial, chronological and analytical resolution has enabled a correct integration of the results of this research with those supplied by the PCR-Mont Lozère project. As a result, a series of land-uses in a mountain environment from the Neolithic to present time has been proposed. A long history of socio-environmental interactions in Mont-Lozère is evidenced. A first shepherding phase in Early Neolithic (4550-4400 cal BC) has been evidenced. During Late Neolithic pastoral practices and related slash-and-burn strategies attain its highest activity. In the Iron Age Period a noticeable deforestation of both foothills and higher environments takes place as a consequence of the overall increase farming and metallurgical activities. Forest clearances increase even more during High-Medieval times, at the same time that farming activities reinforce. During the Middle Ages a more complex and diversified land-use system, including farming, metallurgy, mining and charcoal production, is recorded. The development of farming activities in the Late Medieval resulted in a more evident forest clearance of the Massif. This area remained unchanged until the 19th century, when the decay of agriculture and shepherding occurs and forest replanting in Mont Lozère is recorded. The history of highland herb communities of Nardus stricta correctly matches the main phases of land-use and underlines the key-role of farming in the genesis and evolution of this cultural landscape. / Se han estudiado cinco secuencias sedimentarias en el Mont Lozère con el objetivo de reconstruir la dinámica paisajística y los usos del suelo en la longue durée. La utilización de un análisis multiproxy ha permitido determinar los principales ritmos de antropización y establecer su carácter regional y/o local. La alta resolución espacial, cronológica y analítica hapermitido la integración de resultados con aquellos obtenidos en el marco del PCR-Mont Lozère y proponer los usos de la montaña que han modelado el paisaje cultural desde el Neolítico hasta la actualidad. Se ha evidenciado una larga historia de las interacciones socioambientales en el Mont Lozère, con una primera fase de carácter agropastoral en el Neolítico Antiguo, en ca. 4550-4400 cal BC. El Neolítico Final es una fase de marcado impacto agropastoral en la que se generalizan las quemas para abrir claros en el bosque. En la Edad del Hierro se inicia una marcada deforestación en el piedemonte y los espacios de altitud, coincidiendo con un desarrollo agropastoral y metalúrgico. En el periodo altomedieval se amplifican las deforestaciones coincidiendo con un marcado incremento de las actividades agropastorales. En la Plena Edad Media se evidencia un sistema diversificado que implica metalurgia, agricultura, pastoreo, minería y carboneo. El desarrollo agropastoral de la Baja Edad Media supone una marcada deforestación en el macizo que se extiende hasta mitad del s. XIX, momento en que se inicia el declive del agropastoralismo y empiezan las reforestaciones en el Mont Lozère. La historia de las formaciones herbosas con Nardus stricta de los espacios somitales sigue estas principales fases de antropización y revela el papel clave del agropastoralismo en la génesis y evolución de este paisaje cultural.
120

Estimation et rôle pronostique de la qualité de vie des patients âgés atteints d'un cancer colorectal. . : Etude à partir d'un registre de population / Estimation and prognosis value of elderly colorectal cancer patients' quality of life. : A population-based study

Fournier, Evelyne 29 October 2014 (has links)
Par sa fréquence et sa gravité, le cancer colorectal pose un problème majeur de santé publique en France et touche majoritairement les sujets âgés. Peu d’études évaluant la qualité de vie au diagnostic de ces patients et son impact sur leur survie ont été menées en population générale. Ce travail s'appuie sur une étude de population réalisée par le Registre Bourguignon des cancers digestifs portant sur les patients âgés de 65 ans ou plus et diagnostiqués entre 2003 et 2005 en Saône et Loire. Parmi les 401 patients éligibles, 246 ont renvoyé un questionnaire à au moins un des temps d'étude. Les non-répondeurs étaient plus âgés et diagnostiqués avec un stade tumoral plus avancé. La qualité de vie des patients s'améliorait avec le temps. Elle n'était pas modifiée par la présence de traitements adjuvants. La qualité de vie au diagnostic était un facteur pronostique indépendant de la survie des patients quand elle était évaluée par les patients eux-mêmes. La concordance entre le niveau de qualité de vie déclaré par les patients et l'appréciation de leur qualité de vie par le médecin traitant était moyenne à faible En conclusion, cette étude montre que chez les patients âgés, l'administration d'un traitement adjuvant n’entraîne pas d'altération de la qualité de vie à court et moyen terme, confirmant la nécessité de ne pas prendre uniquement en compte l'âge chronologique lors de la décision thérapeutique. Enfin, elle souligne l'importance de l'évaluation de la qualité de vie par le patient lui-même, y compris dans un contexte d'étude épidémiologique en population réalisée auprès de patients âgés dont il est parfois difficile d'obtenir la participation à une étude. / Colorectal cancer is one of the most common malignancies in France and predominantly affects older patients. Few studies evaluating baseline quality of life of those patients, its short term evolution and its prognosis value on patients' survival have been performed in the context of a population-based study. This work is based on a prospective longitudinal cohort study performed by the Burgundy Digestive Cancer Registry. All patients aged 65 and over, diagnosed with a new colorectal cancer and registered by the Registry between 2003 and 2005 were eligible. Among the 401 eligible patients, 246 fulfilled at least one questionnaire. Non-respondents were older and diagnosed with a more advanced cancer stage.Patients' quality of life improved with time. Quality of life was affected neither by the presence of adjuvant treatment, nor by the palliative or curative intent of cares. Quality of life was an independent prognosis factor of survival, only when assessed by patients themselves. The agreement between the levels of quality of life declared by patients and the level of quality of life estimated by patients' general practitioner was low. In conclusion, this study shows that quality of life is of major importance when evaluating elderly colorectal cancer patients' care. For those patients, adjuvant treatment did not seem to impact quality of life or its evolution with time, suggesting that chronological age should not determine candidacy for treatments. Lastly, it underlines the value of elderly patients' rating of their quality of life in the context of a population based study, even if getting this assessment is challenging.

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