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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.
1

Consolidação de um rejeito de mineração de areia e modelação do enchimento de um reservatório para sua disposição / Sand-mining waste disposal consolidation and a waste reservoir filling process modeling for its storage

Cañabi Quispe, Luis Miguel 04 April 2011 (has links)
Rejeitos de mineração com muita freqüência são dispostos na forma de lama. A capacidade de estocagem das lagoas onde são depositados depende de suas dimensões e formas de operação, mas também das características físicas, compressibilidade e condutividade hidráulica da lama. No presente trabalho estudam-se as características de consolidação de uma lama argilosa resultante da mineração de areia, por meio do ensaio de consolidação hidráulica (HCT) e modela-se o enchimento de uma lagoa de disposição desse rejeito, empregando a teoria de grandes deformações e mediante o software CONDES. Realizaram-se ensaios de caracterização e HCT com amostras coletadas das lagoas 2, 11 e vertedouro da Mineração Jundu Ltda. em Descalvado, São Paulo. Estes parâmetros foram necessários para as análises de simulação numérica do processo de enchimento da Lagoa 11. Os resultados dos ensaios HCT mostraram um conjunto consistente de propriedades constitutivas do material, também se verificou a importância de alcançar a condição estável nas leituras da diferença de pressão entre o topo e a base do corpo de prova, assim obter uma menor variabilidade dos resultados. A simulação de enchimento se mostrou consistente, onde se obteve a evolução do processo de consolidação em diferentes etapas do lançamento da lama. Observou-se uma concordância dos resultados obtidos na simulação de enchimento. Segundo as análises observou-se que a altura dos rejeitos após um período de dois anos é da ordem de 1.57 m. / Mining waste is frequently disposed of in the form of mud. The storage capacity of a collection reservoir of mining waste depends on its dimensions and on its operational processes, which are based on the physical characteristics of the mud and its compressibility and hydraulic conductivity. This research focuses on the study of the consolidation characteristics of a clayey mud resultant from the process of sand mining. Such characteristics were studied through Hydraulic Consolidation Tests (HCT) and by modeling the waste reservoir filling process using large deformation theory and the CONDES software. Characterization and hydraulic consolidation tests were performed on samples obtained from Reservoirs 2 and 11 and from the Jundu Mine spillway at Descalvado City in the state of São Paulo, Brazil. The characterization parameters obtained were employed in performing numerical analysis of the filling process of waste reservoir 11. HCT test results show the acceptable set of constitutive properties of the analyzed material. During the testing procedures, variability of test results were minimized by obtaining stabilized pressure difference readings between the top and bottom leads of the specimen. Modeling was conducted for instantaneous and progressive filling and both methods yielded the same results. It was observed a predictable parity between the results obtained from instantaneous and progressive filling simulations. The final height after consolidation was measured at approximately two years for both instantaneous and progressive methods of filling. From the analysis, the two-year level was measured at 1.57 meter.
2

Consolidação de um rejeito de mineração de areia e modelação do enchimento de um reservatório para sua disposição / Sand-mining waste disposal consolidation and a waste reservoir filling process modeling for its storage

Luis Miguel Cañabi Quispe 04 April 2011 (has links)
Rejeitos de mineração com muita freqüência são dispostos na forma de lama. A capacidade de estocagem das lagoas onde são depositados depende de suas dimensões e formas de operação, mas também das características físicas, compressibilidade e condutividade hidráulica da lama. No presente trabalho estudam-se as características de consolidação de uma lama argilosa resultante da mineração de areia, por meio do ensaio de consolidação hidráulica (HCT) e modela-se o enchimento de uma lagoa de disposição desse rejeito, empregando a teoria de grandes deformações e mediante o software CONDES. Realizaram-se ensaios de caracterização e HCT com amostras coletadas das lagoas 2, 11 e vertedouro da Mineração Jundu Ltda. em Descalvado, São Paulo. Estes parâmetros foram necessários para as análises de simulação numérica do processo de enchimento da Lagoa 11. Os resultados dos ensaios HCT mostraram um conjunto consistente de propriedades constitutivas do material, também se verificou a importância de alcançar a condição estável nas leituras da diferença de pressão entre o topo e a base do corpo de prova, assim obter uma menor variabilidade dos resultados. A simulação de enchimento se mostrou consistente, onde se obteve a evolução do processo de consolidação em diferentes etapas do lançamento da lama. Observou-se uma concordância dos resultados obtidos na simulação de enchimento. Segundo as análises observou-se que a altura dos rejeitos após um período de dois anos é da ordem de 1.57 m. / Mining waste is frequently disposed of in the form of mud. The storage capacity of a collection reservoir of mining waste depends on its dimensions and on its operational processes, which are based on the physical characteristics of the mud and its compressibility and hydraulic conductivity. This research focuses on the study of the consolidation characteristics of a clayey mud resultant from the process of sand mining. Such characteristics were studied through Hydraulic Consolidation Tests (HCT) and by modeling the waste reservoir filling process using large deformation theory and the CONDES software. Characterization and hydraulic consolidation tests were performed on samples obtained from Reservoirs 2 and 11 and from the Jundu Mine spillway at Descalvado City in the state of São Paulo, Brazil. The characterization parameters obtained were employed in performing numerical analysis of the filling process of waste reservoir 11. HCT test results show the acceptable set of constitutive properties of the analyzed material. During the testing procedures, variability of test results were minimized by obtaining stabilized pressure difference readings between the top and bottom leads of the specimen. Modeling was conducted for instantaneous and progressive filling and both methods yielded the same results. It was observed a predictable parity between the results obtained from instantaneous and progressive filling simulations. The final height after consolidation was measured at approximately two years for both instantaneous and progressive methods of filling. From the analysis, the two-year level was measured at 1.57 meter.
3

Uso das técnicas HCT e TDR no monitoramento do proceso de consolidação em reservatórios de barragens de rejeitos / Monitoring of consolidation process in deposits of tailings dam by TDR and HCT techniques

Vagner Albuquerque de Lima 25 September 2009 (has links)
A indústria de mineração gera uma vasta quantidade de rejeitos que são comumente depositados em reservatórios ou lagoas de contenção. Para dimensionar adequadamente estas construções, quando o rejeito é altamente compressível, é necessário estudar as características de consolidação deste material através de técnicas que contemplem grandes deformações. Este trabalho teve como objetivo implantar a técnica HCT (Hydraulic Consolidation Test) nos laboratórios do departamento de Geotecnia da EESC-USP e consolidar a utilização da técnica TDR (Time Domain Reflectometry). Também teve como objetivo avaliar o processo de consolidação de rejeitos argilosos contidos em uma barragem com o uso de técnicas de laboratório (HCT) e de campo (TDR). Nos ensaios de laboratório foi utilizada a técnica HCT, enquanto que em campo foi utilizada a técnica TDR. Em laboratório, realizaram-se ensaios com amostras coletadas na região do vertedouro e do canal de lançamento de rejeitos. Foram realizadas diversas análises com estas amostras utilizando a técnica HCT, tendo como resultado uma pequena variação nos parâmetros de consolidação obtidos. Através destes parâmetros foi calculada a curva de compressibilidade de laboratório. A técnica TDR fez uso de uma sonda desenvolvida especialmente para este fim, sendo realizada uma calibração previa em laboratório com o material da barragem. A técnica TDR apresentou, de forma instantânea, a estimativa do teor de umidade para as sondagens realizadas na barragem de rejeitos. Com os resultados da técnica TDR, os índices de vazios foram calculados por correlações e, por fim, calculadas as tensões efetivas atuantes em cada profundidade estudada, gerando uma curva de compressibilidade de campo. Pode-se então comparar as curvas de compressibilidade de laboratório e campo obtendo-se uma grande proximidade entre os valores. Conclui-se que ambas as técnicas são validas para avaliação do processo de consolidação de materiais moles em barragens de rejeitos. / The mining industry generates a large amount of tailing, which is usually placed in tailing dams. To properly design these constructions, when the tailing is highly compressible, it is necessary to study the consolidation characteristics of this material by means of techniques that consider large deformations. This study aimed to establish the technique HCT (Hydraulic Consolidation Test) in the laboratories of the department of Geotechnical Engineering, EESC-USP and consolidate the use of the technique TDR (Time Domain Reflectometry). This research work also aimed to evaluate the process of consolidation of clayey tailings through laboratory and field tests. For laboratory tests it was used the Hydraulic Consolidation Test (HCT) whereas field tests used the Time Domain Reflectometry (TDR) technique. The laboratory tests were carried out with samples collected in the spillway and next to the discharge spigot. Several analyses were performed using the HCT technique. The analysis results showed very little variations in the consolidation parameter values. The compressibility curve was determined using these consolidation parameters. The TDR tests were carried out using a probe specifically designed for this purpose. Laboratory calibration was performed with samples collected in the dam. One advantage of the TDR technique is to provide in real time estimates of the soil water content. With the water content profiles provided by the TDR technique, void ratio and effective stress profiles were determined using correlations obtained in laboratory, enabling to find a field compressibility curve. Then, the laboratory and field compressibility curves were compared, showing them very close to each other. It was concluded that both techniques are valid for evaluating the process of consolidation of soft materials in tailings dams.
4

Uso das técnicas HCT e TDR no monitoramento do proceso de consolidação em reservatórios de barragens de rejeitos / Monitoring of consolidation process in deposits of tailings dam by TDR and HCT techniques

Lima, Vagner Albuquerque de 25 September 2009 (has links)
A indústria de mineração gera uma vasta quantidade de rejeitos que são comumente depositados em reservatórios ou lagoas de contenção. Para dimensionar adequadamente estas construções, quando o rejeito é altamente compressível, é necessário estudar as características de consolidação deste material através de técnicas que contemplem grandes deformações. Este trabalho teve como objetivo implantar a técnica HCT (Hydraulic Consolidation Test) nos laboratórios do departamento de Geotecnia da EESC-USP e consolidar a utilização da técnica TDR (Time Domain Reflectometry). Também teve como objetivo avaliar o processo de consolidação de rejeitos argilosos contidos em uma barragem com o uso de técnicas de laboratório (HCT) e de campo (TDR). Nos ensaios de laboratório foi utilizada a técnica HCT, enquanto que em campo foi utilizada a técnica TDR. Em laboratório, realizaram-se ensaios com amostras coletadas na região do vertedouro e do canal de lançamento de rejeitos. Foram realizadas diversas análises com estas amostras utilizando a técnica HCT, tendo como resultado uma pequena variação nos parâmetros de consolidação obtidos. Através destes parâmetros foi calculada a curva de compressibilidade de laboratório. A técnica TDR fez uso de uma sonda desenvolvida especialmente para este fim, sendo realizada uma calibração previa em laboratório com o material da barragem. A técnica TDR apresentou, de forma instantânea, a estimativa do teor de umidade para as sondagens realizadas na barragem de rejeitos. Com os resultados da técnica TDR, os índices de vazios foram calculados por correlações e, por fim, calculadas as tensões efetivas atuantes em cada profundidade estudada, gerando uma curva de compressibilidade de campo. Pode-se então comparar as curvas de compressibilidade de laboratório e campo obtendo-se uma grande proximidade entre os valores. Conclui-se que ambas as técnicas são validas para avaliação do processo de consolidação de materiais moles em barragens de rejeitos. / The mining industry generates a large amount of tailing, which is usually placed in tailing dams. To properly design these constructions, when the tailing is highly compressible, it is necessary to study the consolidation characteristics of this material by means of techniques that consider large deformations. This study aimed to establish the technique HCT (Hydraulic Consolidation Test) in the laboratories of the department of Geotechnical Engineering, EESC-USP and consolidate the use of the technique TDR (Time Domain Reflectometry). This research work also aimed to evaluate the process of consolidation of clayey tailings through laboratory and field tests. For laboratory tests it was used the Hydraulic Consolidation Test (HCT) whereas field tests used the Time Domain Reflectometry (TDR) technique. The laboratory tests were carried out with samples collected in the spillway and next to the discharge spigot. Several analyses were performed using the HCT technique. The analysis results showed very little variations in the consolidation parameter values. The compressibility curve was determined using these consolidation parameters. The TDR tests were carried out using a probe specifically designed for this purpose. Laboratory calibration was performed with samples collected in the dam. One advantage of the TDR technique is to provide in real time estimates of the soil water content. With the water content profiles provided by the TDR technique, void ratio and effective stress profiles were determined using correlations obtained in laboratory, enabling to find a field compressibility curve. Then, the laboratory and field compressibility curves were compared, showing them very close to each other. It was concluded that both techniques are valid for evaluating the process of consolidation of soft materials in tailings dams.
5

Die prognostische Bedeutung von Komorbiditäten bei Patienten nach allogener Blutstammzelltransplantation mit reduzierter Konditionierung

Hoffmann, Annekathrin 01 February 2016 (has links) (PDF)
Untersuchung des Einflusses von Komorbiditäten auf Patienten mit allogener Stammzelltransplantation nach reduzierter Konditionierung, Überprüfung der Validität des HCT-CI an Leipziger Patienten
6

Preventing the spread of Tuberculosis via refugees, asylum seekers and immigrants entering Sweden : A study of health communication, prevention strategies, policies and recommendations

Ahmed, Iqra Shahzadi January 2013 (has links)
Sverige har under många decennier sett en minskning av tuberkulos (TBC), men infektionen har kontinuerligt ökat från 2003. Majoriteten av TBC-fallen är personer som är födda utanför Sverige. Hälsotillståndet har förbättrats i Sverige men det finns fortfarande problem. Kommunikationen mellan flyktingar och sjukvårdsspecialister är bristande idag, vilket resulterar att endast ett fåtal genomgår hälsokontroller. Detta kan leda till en ökning av infektioner och sjukdomar i Sverige. Denna studie undersöker hur hälsokommunikationen idag fungerar mellan den svenska sjukvården, nyanlända immigranter, asylsökande och flyktingar, samt vilken typ av vård som finns tillgänglig för flyktingar med hög risk för att utveckla TBC. Specifikt syftar studien till att förstå på vilket sätt kommunikation brister på samt analysera vilka sätt det finns för att en reducering av TBC i Sverige ska kunna ske och hur kommunikationen kan förbättras. Studien har genomförts med hjälp av både primära källor i form av intervjuer och sekundära källor. Baserat på de intervjuer och sekundära källor som genomförts i studien dras slutsatsen att trots att den svenska sjukvården utvecklas positivt så finns det en hel del brister - hälsokommunikation är bristande idag mellan nyanlända flyktingar, sjukvårdspersonal och myndigheter. En av huvudorsakerna som informanterna i studien nämnt är språket, mycket av det som skrivs och sägs är på svenska. Det är viktigt att en mer välfungerad hälsokommunikation utvecklas mellan de nyanlända flyktingarna, sjukvårdspersonal och myndigheterna för att det ska kunna underlättas för flyktingar att söka vård och samarbeta med sjukvårdspersonal med deras arbete för att kunna förhindra spridning av TBC och andra sjukdomar och infektioner i Sverige. / Sweden has for many decades witnessed a decrease of the spread of tuberculosis (TB), but between the years of 2003-2012 a new pattern has emerged with refugees carrying TB entering the country and contributing to a situation where the infection has slowly begun to spread again. The communication between the refugees and the health professionals has been inefficient, which inevitably results in fewer refugees undergoing health examinations. This in turn can lead to an increase of infections and diseases. The purpose of this study is to examine the current health communication between Swedish health professionals and immigrants, asylum seekers and refugees, and to give an overview of what type of health care currently exist for refugees with a high risk of TB. This is done to understand what is missing in the communication process, what has been done in order to improve the situation, and how it can be further improved in order to prevent TB. In order to fulfill the purpose of this study, a qualitative method has been used combining text analysis of interviews and secondary sources. This study has shown based on the interviews and secondary sources that the Swedish prevention work regarding TB is developing positively in general, but the communication between newly arrived refugees, health professionals and authorities in Sweden is lacking due to the fact that most of what is written and said in this communication process is in Swedish. This makes it difficult for the refugees to understand what is communicated and is stated as one of the main reasons why many refugees do not undergo health examinations, combined with the lack of awareness. Therefore a better functioning health communication between refugees, authorities and health professionals is required to support refugees seeking health care, as well as co-operating with health professionals to prevent the spread of not only TB but other infections and diseases in Sweden.
7

Utvärdering av informationsutbyte vid konsolidering och de-konsolidering av stora mängder god / Evaluation of information exchange at consolidation and de-consolidation of large amount of goods

Granlund, Anna, Alm, Linnea, Magnusson, Sofia January 2017 (has links)
Vid en hypotetisk torrhamn i Viared där HCT-fordon förväntas användas kommer bådekonsolidering och de-konsolidering att förekomma. Den ökade kapacitet som är möjlig attlasta på ett HCT fordon, jämfört med ett normalt fordon, bidrar till att det är mer gods somska de-konsolideras vid ankomst till terminal. För att gods inte skall bli stående på terminalenkrävs ett tydligt informationsutbyte, vilket det inte finns mycket studier kring kopplat till HCTtransporter.Syftet med examensarbetet är att undersöka informationsutbyte vid konsolidering och dekonsolidering.Arbetet kommer utgå ifrån frågeställningen om hur ett effektivt kaninformationsutbyte skapas i samband med stora volymer av gods.En av slutsatserna som kan dras efter fallstudien på Kerry Logistics är att en ökad mängd godsendast kommer bidra till volymproblem, främst i form av resursbrist. Det skulle därför intevara svårare ur ett HCT-perspektiv, utan ju mer gods som kommer samtidigt desto störretryck blir det på informationsutbytet.Att ligga steget före med informationsutbytet vid hantering och planering av stora mängdergods framgår också vara av stor vikt. Med nödvändig information tillgänglig vid rätt tillfälleeffektiviseras informationsutbytet. Olika åsikter och uppfattningar kring vilken informationsom klassas som nödvändig och önskvärd har gjort det svårt att dra slutsatser kring de berördainformationsattributens roll. Goda affärsrelationer har däremot visat sig spela en stor roll vidett effektivt informationsutbyte. / At a hypothetical dry port in Viared where HCT-vehicles are expected to be used, bothconsolidation and de-consolidation will occur. The increased capacity of freight that ispossible to load on a HCT-vehicle, compared to a normal vehicle, contributes to the fact thatthere is more freight to be de-consolidated on arrival at the terminal. In order for goods not tobe left at the terminal, a clear exchange of information is required as there is not much studiesrelated to HCT-transport. The purpose of the thesis is to explore the information exchangerelated to consolidation and de-consolidation of goods.One of the conclusions that can be drawn from the case study at Kerry Logistics is that anincreased amount of goods only will contribute to problems related to volume, primarily inlack of resources. The informations exchange will not be more difficult from an HCTperspective, but when greater amount of freight arrives at the same time the pressure willincrease on the information exchange.To be ahead of the information exchange when it comes to handling and planninglarger amounts of goods is also important. With the necessary information available at theright time, the information exchange will be more efficient. Different opinions andperceptions about what information that should be classified as necessary and/or desirable hasmade it difficult to draw conclusions about the role of the relevant information attributes.Good business relations on the other hand, have proven to play a major role in order to createefficient information exchange.
8

Die prognostische Bedeutung von Komorbiditäten bei Patienten nach allogener Blutstammzelltransplantation mit reduzierter Konditionierung: Die prognostische Bedeutung von Komorbiditäten bei Patientennach allogener Blutstammzelltransplantation mit reduzierterKonditionierung

Hoffmann, Annekathrin 21 January 2016 (has links)
Untersuchung des Einflusses von Komorbiditäten auf Patienten mit allogener Stammzelltransplantation nach reduzierter Konditionierung, Überprüfung der Validität des HCT-CI an Leipziger Patienten
9

En samverkan mellan högkapacitetstransporter och torrhamnar : Kartlagt utifrån triple bottom line / A synergy between High Capacity Transporting and Dry Ports : Charter based on triple bottom line

Larsson, Cajsa, Johansson, Lina January 2017 (has links)
Hållbarhet har blivit ett aktuellt ämne inom de flesta verksamheter och strävan är erhålla en ekonomisk vinning utan att äventyra naturresurser, människan och samhället. Verksamheters förmåga att distribuera gods säkert, snabbt och kostnadseffektivt är avgörande för internationell och inrikes handel och ekonomisk utveckling. Godstransporter är en stor källa till utsläpp av växthusgaser och därför är det viktigt att nya transportlösningar hittas för att minska de avtryck som godstransporter gör i en försörjningskedja. Användningen av så kallade högkapacitetsfordon, HCT-fordon, förväntas öka då möjligheten att köra lastbilar som överskrider EU:s dimensioner för längd, bredd och vikt kan medföra ökad effektivitet och reducerad miljöpåverkan. Även konceptet torrhamnar, det vill säga en anläggning med en terminal som drivs likt en hamn, kan användas för att konsolidera gods, avlasta hamnen och öka intermodaliteten hos godset. Intermodalitet innebär att godset fraktas från A till B med hjälp av en kombination av flera olika typer av fraktsätt, exempelvis sjö, tåg och lastbil.   Följande rapport kartlägger hur en samverkan mellan högkapacitetsfordon och torrhamnar skulle kunna se ut. Detta genomförs med hjälp av att utifrån hållbarhetsmodellen triple bottom line som avser de tre dimensionerna ekonomi-, miljö- och sociala effekter, identifiera styrkor och svagheter hos begreppen. Med hjälp en teoretisk litteraturstudie, en fallstudie av ETT-projektet, en observation av Skaraborg Logistics Center samt nio stycken intervjuer med experter inom området, analyseras effekterna av en samverkan mellan högkapacitetsfordon och torrhamnar.   Rapporten identifierar att bättre ekonomiska-, miljömässiga och sociala effekter nås om en torrhamn är kopplad till ursprungshamnen med järnväg snarare än med HCT-fordon. Ytterligare identifierad problematik där en torrhamn försörjs med HCT-fordon utgörs av de tillfälliga tillstånden för att få framföra de längre och tyngre lastbärarna. Analysen visar att för att uppnå en god effekt från en samverkan mellan HCT-fordon och torrhamnar krävs att varje begrepp ensamt uppnår de faktorer som krävs för god effekt.   Rapporten är avgränsad till att räkna allt gods som normalt gods, endast avse HCTtransporter på väg samt att förutsätta att svenska arbetsregler följs vid inrikes transporter på väg. Rapporten studerar inte detaljer kring potentiell utveckling inom tekniken, exempelvis säkerhetssystem, IT-system eller aerodynamik. / Sustainability has become a highly prioritized subject among most companies and the goal is to maintain financial value without jeopardizing nature's resources, neither human health nor the society. How safe, fast and cost efficient a company distribute their goods is crucial for international- and domestic trade as well as economic growth. Haulage is a great source of greenhouse gas emissions and therefore it is crucial that new solutions of transport are developed in order to reduce the negative footprint of haulage in a supply chain. The use of high capacity transporting (HCT) vehicles is assumed increase when the EU's dimensions for a truck’s length, width and weight are allowed. This exception from EN standards would lead to increased transport efficiency, economic efficiency and reduced impact on the environment. The logistical solution of dry ports, namely a port on inland, can be used to consolidate goods, unburden the port and increase intermodality within the goods. Intermodality is when goods is transported between its starting location to its end location using several different kinds of transport ways.  The following report maps how a synergy between high capacity vehicles and dry ports would look like. By using the triple bottom line sustainability model the report identifies strengths and weaknesses of the two concepts. The reports analysis is created from a theoretical literature study, a case study of the ETT project, an observation of Skaraborg Logistics Center and nine interviews with experts within the field. The report identifies that better economic, environmental and social effects are achieved if a dry port is connected to the port of origin by rail way rather than with HCT vehicles. Further identified problems is the temporary permit of conveying the longer and heavier vehicles. The analysis shows that in order to achieve a good effect from an interaction between HCT vehicles and dry ports, each term alone require that the necessary factors for good effect is fulfilled.  The reports limitations are to consider all goods being normal gods and only to consider HCT-vehicles, not HCT-haulage by rail way. The writers also make the assumption that Swedish rules of labor are applied on domestic transportations by road. The report does not study details within IT, security systems nor aerodynamic.
10

Régulation de la migration des cellules cancéreuses coliques HCT-116 par la sous-unité α1D et du canal SK3 par la voie AMPc-PKA / Regulaiton of the migration of the HCT-116 colonic cancer cells by the alpha1D subunit and the SK3 channel via the cAMP-PKA pathway

Fourbon, Yann 06 October 2017 (has links)
De plus en plus d'études désignent les canaux K+ et Ca2+ comme de nouvelles cibles très prometteuses pour des thérapies anticancéreuses. Parmi ces canaux, les canaux SK3 et CaV1.3 ont été identifiés comme des régulateurs de la migration des cellules cancéreuses. Lors de mes travaux de thèse, nous avons découvert une nouvelle voie de signalisation montrant que la protéine αlD du canal CaVl.3 est impliquée dans la régulation de l'homéostasie Ca2+ ainsi que dans la migration cellulaire, par un mécanisme indépendant de sa fonction canonique. En parallèle nous avons identifié des résidus sérines du canal SK3 qui sont importants dans la régulation négative du canal SK3 par l'activation de la voie AMPc-PKA. Ces résultats suggèrent également que l'Ohmline, un éther-lipide de synthèse, inhibiteur du canal SK3, ne réduit pas l' activité du canal SK3 en favorisant sa phosphorylation suite à l'activation de la voie AMPc-PKA. / Many studies show that K+ and Ca2+ channels are promising new targets for anticancer therapies. Among these channels, SK3 and Ca V 1.3 ion channels have been identified as regulators of cancer cell migration. Here, we have discovered a new signalization pathway showing that the αlD protein of the CaV1 .3 channel is involved in the regulation of Ca2+ homeostasis and in cell migration by a mechanism independent of its canonical function. In parallel, we have identified serine residues of SK3 channel that are important in the negative regulation of the SK3 channel by activation of the cAMP-PKA pathway. These results also suggest that Ohmline, a synthetic ether-lipid, and inhibitor of SK3 channel, does not reduce the activity of SK3 channel by promoting its phosphorylation following the activation of the cAMP-PKA pathway.

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