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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.
881

Bilevel programming problems: analysis, algorithms and applications

Chen, Yang January 1993 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
882

Optimering av beslutsstöd inom verksamhetsstyrning genom en undersökning av artificiell intelligens : En djupgående undersökning av effektiva AI-tekniker för bättre affärsbeslut / Optimizing decision support in business management through an artificial intelligence study : An in-depth survey of effective AI techniques for better business decisions

Sakhai, Aram January 2024 (has links)
Denna studie undersöker hur artificiell intelligens (AI) kan optimera beslutsstödet inom verksamhetsstyrning genom analys av ostrukturerad data. Genom att granska begrepp som verksamhetsstyrning, Business Intelligence (BI), AI och maskininlärning (ML), belyser studien hur dessa teknologier kan förbättra organisationers beslutsprocesser. Verksamhetsstyrning syftar till att samordna och optimera organisationens delar för att nå gemensamma mål. AI (NLP, ML) samt särskilt genom BI spelar en avgörande roll genom att förbättra effektivitet och kvalitet. BI samlar och analyserar affärsinformation, medan ML möjliggör automatisk lärande från data. Studiens problemområde identifierar utmaningen med att hantera stora mängder ostrukturerad data. Trots AI:s potential att förbättra beslutsfattandet har dess fulla potential ännu inte realiserats. Genom att undersöka effektiv användning av AI för ostrukturerad data, bidrar studien till en bättre förståelse av hur AI kan förbättra beslutsstödet.Den kvalitativa ansatsen använde semistrukturerade intervjuer med IT-experter för att samla insikter om AI:s användning i beslutsfattande. Respondenterna beskrev hur AI analyserar data, förutsäger trender, optimerar processer och personaliserar kundupplevelser. AI automatiserar också tidskrävande uppgifter, vilket ökar effektiviteten och frigör tid för strategiskt arbete. Det visar att AI kan förbättra datakvalitet, automatisera processer och ge djupare insikter i kundbeteenden och marknadstrender. AI:s förmåga att hantera ostrukturerad data möjliggör identifiering av trender och mönster som annars skulle vara svåra att upptäcka. Utmaningar med AI-implementering inkluderar systemintegrering och behovet av teknisk expertis. Sammanfattningsvis visar studien att AI har stor potential att optimera beslutsstödet inom verksamhetsstyrning genom analys av ostrukturerad data.
883

Tubular All Vanadium and Vanadium/Air Redox Flow Cells

Ressel, Simon Philipp 18 November 2019 (has links)
[ES] Un aumento de la generación de energía a partir de fuentes renovables (solar, eólica) requiere una alta flexibilidad de las redes eléctricas. En este sentido, las baterías de flujo redox de vanadio (BFRV) han demostrado una excelente capacidad para proporcionar dicha flexibilidad, mediante el almacenamiento eficiente de energía eléctrica en el rango de los kWh a los MWh. Sin embargo, sus elevados costes son en la actualidad unos de los mayores inconvenientes que dificultan una amplia penetración en el mercado. En la presente Tesis Doctoral se presenta el desarrollo y evaluación de una celda tubular especialmente diseñada con una membrana de 5.0mm. Las células tubulares así diseñadas deberían alcanzar una mayor densidad de potencia (kWm^(-3)). Del mismo modo, la sustitución de uno de los electrodos por un electrodo bifuncional de aire debería de incrementar la energía específica de dicha celda (Whkg^(-1)) y reducir, por tanto, los costes energéticos asociados (€/kWh). El diseño de la celda desarrollado en la presente Tesis Doctoral facilita la fabricación de los colectores y membranas actuales con el empleo de procesos de extrusión y marca un paso importante hacia la fabricación rentable de semiceldas y celdas completas en el futuro. Para evaluar el comportamiento de la nueva celda diseñada se han llevado a cabo estudios de polarización, de espectroscopia de impedancia, y medidas de ciclos de carga/descarga. Las celdas desarrolladas presentan una corriente de descarga máxima de 89.7mAcm^(-2) y una densidad de potencia de 179.2kW/m^3. Además, los bajos sobrepotenciales residuales obtenidos en los electrodos de la celda resultan prometedores. No obstante, la resistencia del área específica de celda de 3.2 ohm*cm² impone limitaciones significativas en la densidad de corriente. Eficiencias Coulomb del 95 % han sido obtenidas, comparables a los valores alcanzados en celdas planas de referencia. Sin embargo, las pérdidas óhmicas resultan elevadas, reduciendo la eficiencia energética del sistema al 56 %. Las celdas tubulares fabricadas con un electrodo de difusión de gas de una sola capa con Pt/IrO2 como catalizador permiten alcanzar densidades de corriente máximas de 32mAcm^(-2) (Ecell =2.1 V/0.56V Ch/Dch). Los elevados sobrepotenciales de activación y el reducido voltaje en circuito abierto (debido a potenciales mixtos) conducen a una densidad de potencia comparativamente baja de 15.4mW/ cm². El paso de iones de vanadio a través de la membrana se considera uno de los grandes inconvenientes en este tipo de celdas tubulares, lo que lleva a que la densidad de energía real de 23.2Wh l^(-1) caiga por debajo del valor nominal de 63.9Wh l^(-1). / [CA] Un augment de la generació d'energia a partir de fonts renovables (solar, eòlica) requereix una alta flexibilitat de les xarxes elèctriques. En aquest sentit, les bateries de flux redox de vanadi (VRFB) han demostrat una excel·lent capacitat per a proporcionar aquesta flexibilitat, mitjançant l'emmagatzematge eficient d'energia elèctrica en el rang dels kWh als MWh. En la present Tesi Doctoral es presenta el desenvolupament i avaluació d'una cel·la tubular especialment dissenyada amb una membrana de 5.0mm. Les cèl·lules tubulars així dissenyades haurien assolir una major densitat de potència (kWm^(-3)). De la mateixa manera, la substitució d'un dels elèctrodes per un elèctrode bifuncional d'aire hauria d'incrementar l'energia específica d'aquesta cel·la (Whkg^(-1)) i reduir, per tant, els costos energètics associats (€/kWh). El disseny de la cel·la desenvolupat en la present tesi doctoral facilita la fabricació dels col·lectors i membranes actuals amb l'ocupació de processos d'extrusió i marca un pas important cap a la fabricació rendible de semiceldas i cel·les completes en el futur. Per avaluar el comportament de la nova cel·la dissenyada s'han dut a terme estudis de polarització, d'espectroscòpia d'impedància, i mesures de cicles de càrrega/ descàrrega. Les cel·les desenvolupades presenten un corrent de descàrrega màxima de 89.7mAcm^(-2) i una densitat de potència de 179.2kW/m^3. A més, els baixos sobrepotencials residuals obtinguts en els elèctrodes de la cel·la resulten prometedors. No obstant això, la resistència de l'àrea específica de cel·la de 3.2 ohm*cm² imposa limitacions significatives en la densitat de corrent. Eficiències Coulomb del 95 % han estat obtingudes, comparables als valors assolits en cel·les planes de referència. No obstant això, les pèrdues òhmiques resulten elevades, reduint l'eficiència energètica del sistema al 56 %. Les cel·les tubulars fabricades amb un elèctrode de difusió de gas d'una sola capa amb Pt/IrO2 com a catalitzador permeten assolir densitats de corrent màximes de 32mAcm^(-2) (Ecell =2.1 V/0.56V Ch/Dch). Els elevats sobrepotencials d'activació i el reduït voltatge en circuit obert (a causa de potencials mixtes) condueixen a una densitat de potència comparativament baixa de 15.4mW/ cm². El pas de ions de vanadi a través de la membrana es considera un dels grans inconvenients en aquest tipus de cel·les tubulars, el que porta al fet que la densitat d'energia real de23.2Wh l^(-1) caigui per sota del valor nominal de 63.9Wh l^(-1). / [EN] An increase of the power generation from volatile renewable sources (solar, wind) requires a high flexibility in power grids. All Vanadium Redox Flow Batteries (VRFBs) have demonstrated their ability to provide flexibility by storing electrical energy on a kWh to MWh scale. High power and energy specific costs do, however prevent a wide market penetration. In this dissertation a tubular cell design with a membrane diameter of 5.0mm is developed and evaluated. Tubular VRFB cells shall lead to an enhanced power den- sity (kWm^(-3)). Replacement of an electrode with a bifunctional air electrode (Vanadium/ Air Redox Flow Battery) shall allow to increase the specific energy (Whkg^(-1)) and reduce energy specific costs (€/kWh). The developed design facilitates a fabrication of the current collectors and membrane by an extrusion process and marks an important step towards the cost-efficient ex- trusion of entire half cells and cells in the future. To evaluate the cell performance and investigate loss mechanisms, polarization curve, electrochemical impedance spectroscopy and charge/discharge cycling measurements are conducted. Tubular VRFB cells with flow-by electrodes reveal a maximum dis- charge current and power density of 89.7mAcm^(-2) and 179.2kW/m^3, respectively. Low residual overpotentials at the cell's electrodes are encouraging, but the area spe- cific cell resistance of 3.2 ohm*cm² imposes limitations on the current density. Coulomb efficiencies of 95% are comparable to values of planar reference cells, but high ohmic losses reduce the system energy efficiency to 56 %. Tubular VARFB cells with a mono-layered gas diffusion electrode and a Pt/IrO2 catalyst allow for a maximum current density of 32mAcm^(-2) (Ecell =2.1 V/0.56V Ch/Dch). High activation overpotentials and a reduced open-circuit voltage (due to mixed potentials) lead to a comparably low power density of 15.4mW/ cm². Cross- over of vanadium ions through the membrane are considered as a major drawback for tubular VARFB cells and the actual energy density of 23.2Wh l^(-1) falls below the nominal value of Wh l^(-1). / Financial support of my research activities was provided by the BMBF through the common research project tubulAir±. / Ressel, SP. (2019). Tubular All Vanadium and Vanadium/Air Redox Flow Cells [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/131203
884

Serial and Parallel Elastic Cable Driven Actuator (SPECA) to Achieve Efficient and Safe Human Robot Physical Interaction

Al-Ani, Al-Muthanna 01 January 2024 (has links) (PDF)
In this thesis, design, integration and validation of Serial and Parallel Elastic Cable Actuator (SPECA) is presented with an aim to enhance human-device interaction in cable-driven systems of wearable robots and to optimize actuator force and power delivery to the user. Adding springs in series and in parallel to the cables acted on the mechanical joint for motion or force control have been shown individually to reduce mechanical power consumption and therefore electrical power consumption. SPECA combines both serial elastic (SE) and parallel elastic (PE) components to explore the compounded effects on a dual cable driven system controlled by a single actuator. A bi-articulating winch attached to the actuator allows control of two cables to achieve a bidirectional control of a revolute joint. Expanding the control of the single actuator, the dual cables route to a mechanical clutch that can engage up to two external winches, or four cables, simultaneously. SPECA is built as an isolated system with only the two winches of the clutch leading to end effectors creating a design capable of being integrated into many cable driven systems. A Simulink model is developed of a simple two degree of freedom (DOF) system to confirm that SE and PE elements not only increase the effective range of a system but lower the mechanical power. SPECA undergoes static and dynamic experiments to explore SE and PE in an applied system confirming the conclusions of the model along with recommendations based on observed characteristics from the experiments. SPECA serves as an exploratory and modular proof of concept for the integration of SE and PE components into many cable driven systems.
885

An Analysis of the 5D Stationary Bi-Axisymmetric Soliton Solution to the Vacuum Einstein Equations / On the 5D Soliton Solution of the Vacuum Einstein Equations

Zwarich, Sebastian 11 1900 (has links)
We set out to analyze 5D stationary and bi-axisymmetric solutions to the vacuum Einstein equations. These are in the cohomogeneity 2 setting where the orbit space is a right half plane. They can have a wide range of behaviour at the boundary of the orbit space. The goal is to understand in detail the soliton example in Khuri, Weinstein and Yamada's paper ``5-dimensional space-periodic solutions of the static vacuum Einstein equations". This example is periodic and has alternating axis rods as its boundary data. We start by deriving the harmonic equations which determines the behaviour of the metric in the interior of the orbit space. Then we analyze what conditions the boundary data imposes on the metric. These are called the smoothness conditions which we derive for solely the alternating axis rod case. We show that with an ellipticity assumption they predict that the twist potentials are constant and that the metric is of the form which appears in Khuri, Weinstein and Yamada's paper. We then analyze the Schwarzschild metric in its standard form which is cohomogeneity 1 and its Weyl form which is cohomogeneity 2. This Weyl form can be made periodic and this serves as an inspiration for the examples in Khuri, Weinstein and Yamada's paper. Finally we analyze the soliton example in detail and show that it satisfies the smoothness conditions. We then provide a new example which has a single axis rod on the boundary with non-constant twist potentials but that is missing a point on the boundary. / Thesis / Master of Science (MSc) / We study the geometry of 5D blackholes. These blackholes are idealized by certain spatial symmetries and time invariance. They are solutions to the vacuum Einstein equations. The unique characteristic of these blackholes is the range of behaviour they may exhibit at the boundary of the domain of outer communication. There could be a standard event horizon called a horizon rod or an axis rod where a certain part of the spatial symmetry becomes trivial. In this thesis we start by deriving the harmonic map equations which are satisfied in the interior of the domain of communication. Then we show how this boundary data affects the metric through the smoothness conditions. We then analyze the soliton example in a paper by Khuri, Weinstein and Yamada and show that it respects the smoothness conditions. We then provide a new example which is interesting in the fact it has non-constant twist potentials.
886

Guidance and Control System for VTOL UAVs operating in Contested Environments

Binder, Paul Edward 01 March 2024 (has links)
This thesis presents the initial components of an integrated guidance, navigation, and control system for vertical take-off and landing (VTOL) autonomous unmanned aerial vehicles (UAVs) such that they may map complex environments that may be hostile. The first part of this thesis presents an autonomous guidance system. For goal selection, the map is partitioned around the presence of obstacles and whether that area has been explored. To perform this partitioning, the Octree algorithm is implemented. In this thesis, we test this algorithm to find a parameter set that optimizes this algorithm. Having selected goal points, we perform a comparison of the LPA* and A* path planning algorithms with a custom heuristic that enables reckless or tactical maneuvers as the UAV maps the environment. For trajectory planning, the fMPC algorithm is applied to the feedback-linearized equations of motion of a quadcopter. For collision avoidance, standalone versions of 4 different constraint generation algorithms are evaluated to compare their resulting computation times, accuracy, and computed volume on a voxel map that simulates a 2-story house along with fixed paths that vary in length at fixed intervals as basis of tests. The second part of this thesis presents the theory of Model Reference Adaptive Control(MRAC) along with augmentation for output signal tracking and switched-dynamic systems. We then detail the development of longitudinal and lateral controllers a Quad-Rotor Tailsitter(QRBP) style UAV. In order to successfully implement the proposed controller on the QRBP, significant effort was placed upon physical design and testing apparatus. / Master of Science / For an autonomously operated, Unmanned Aerial Vehicle (UAV), to operate, it requires a guidance system to determine where and how to go, and a control system to effectively actuate the guidance system's commands. In this thesis, we detail the characterization and optimization of the algorithms comprising the guidance system. We then delve into the theory of MRAC and apply it toward a control system for a QRBP. We then detail additional tools developed to support the testing of the QRBP.
887

Quantum Coherence Effects Coupled via Plasmons

Moazzezi, Mojtaba 12 1900 (has links)
This thesis is an attempt at studying quantum coherence effects coupled via plasmons. After introducing the quantum coherence in atomic systems in Chapter 1, we utilize it in Chapter 2 to demonstrate a new technique of detection of motion of single atoms or irons inside an optical cavity. By taking into account the interaction of coherences with surface plasmonic waves excited in metal nanoparticles, we provide a theoretical model along with experimental data in Chapter 3 to describe the modification of Raman spectra near metal nanoparticles. We show in chapter 4 that starting from two emitters, coupled via a plasmonic field, the symmetry breaking occurs, making detectable the simultaneous existence of the fast super-radiance and the slow sub-radiance emission of dye fluorescence near a plasmonic surface. In Chapter 5, we study the photon statistics of a group of emitters coupled via plasmons and by the use of quantum regression theorem, we provide a theoretical model to fully investigate the dependence of photon bunching and anti-bunching effects to the interaction between atoms, fields and surrounding mediums.
888

Statistical properties of the liquidity and its influence on the volatility prediction / Statistical properties of the liquidity and its influence on the volatility prediction

Brandejs, David January 2016 (has links)
This master thesis concentrates on the influence of liquidity measures on the prediction of volatility and given the magic triangle phenomena subsequently on the expected return. Liquidity measures Amihud Illiquidity, Amivest Liquidity and Roll adjusted for high frequency data have been utilized. Dataset used for the modeling was consisting of 98 shares that were traded on S&P 100. The time range was from 1st January 2013 to 31st December 2014. We have found out that the liquidity truly enters into the return-volatility relationship and influences these variables - the magic triangle interacts. However, contrary to our hypothesis, the model shows up that lower liquidity signifies lower realized risk. This inference has been suggested by all three models (3SLS, 2SLS and OLS). Furthermore, we have used the realized variance and bi-power variation to separate the jump. Our second hypothesis that lower liquidity signifies higher frequency of jumps was confirmed only for one of two liquidity proxies (Roll) included in the resulting logit FE model. Keywords liquidity, risk, volatility, expected return, magic triangle, price jumps, realized variance, bi-power variation, three-stage least squares model, logit, high-frequency data, S&P 100 Author's e-mail david.brandejs@seznam.cz Supervisor's e-mail...
889

Geovisualização analítica: desenvolvimento de um protótipo de um sistema analítico de informações para a gestão da coleta seletiva de resíduos urbanos recicláveis. / Analytical geovisualization: development of a prototype of an analytical information system for the management of the selective collection of recycled urban solid waste.

Hernández Simões, Carlos Enrique 16 April 2010 (has links)
Os resíduos urbanos descartados de forma irregular constituem um problema sério, principalmente nas grandes cidades, causando entupimento de bueiros e drenagem com conseqüentes inundações, sujeira e transmissão de doenças tais como leptospirose e dengue além de ser um estorvo para o trânsito e acarretarem gastos para a Prefeitura. Por outro lado, reciclar este material é uma fonte de receitas e um gerador de empregos. A Geovisualização Analítica pode ser de grande auxílio para a análise desse problema complexo e para a tomada de decisão. Com essa motivação, a presente dissertação procura fornecer uma visão geral sobre o estado da arte quanto a conceitos e pesquisas em Geovisualização (GVis) e Processamento Analítico (OLAP e SOLAP). Apresenta também processos, metodologias e tecnologias que foram utilizadas no desenvolvimento de um protótipo de um sistema analítico de informações aplicado à área de gestão da coleta seletiva de resíduos sólidos recicláveis em ambiente urbano. Este protótipo, efetivamente implantado, combinou navegação e consulta para recuperar informações através de seleções espaciais e alfanuméricas. Através de exemplos foi mostrado que este tipo de solução auxilia gestores nos processos de exploração, análise e tomada de decisão. / Domestic waste illegally disposed constitute a serious problem, especially in large cities, causing clogging of drains and drainage with subsequent flooding, dirt and transmission of diseases such as leptospirosis and dengue as well as being a hindrance to traffic and would entail city hall costs. Moreover, recycle this material is a source of revenue and a generator of jobs. The Analytical Geovisualization can be of great help in the analysis of this complex problem and the decision-making. With this motivation, this paper seeks to provide an overview of the state of the art as the concepts and research in Geovisualization (GVis) and Analytical Processing (OLAP and SOLAP). It also presents processes, methodologies and technologies that were used in developing a prototype of an analytical system applied to the area of selective collection information management of recyclable solid waste in urban environments. This prototype, effectively deployed, combined navigation and query to retrieve information through spatial and alphanumeric selections. Through examples it was shown that this type of solution helps managers in operating procedures, analysis and decision making.
890

Receptor scavenger BI: efeito de polimorfismos e atorvastatina na expressão gênica em indivíduos hipercolesterolêmicos / Scavenger receptor class BI: polymorphisms and atorvastatin effects on gene expression in hypercholesterolemic individuals

Maureira, Álvaro Danilo Cerda 20 May 2009 (has links)
O receptor scavenger classe B tipo I (SR-BI) media a captação seletiva do colesterol da lipoproteina de alta densidade (HDL) e participa no effluxo do colesterol livre para aceptores lipoprotéicos. A HDL tem um importante rol aterogênico associado com sua participação no transporte reverso do colesterol. Polimorfismos no gene que codifica para o SR-BI (SCARB1) foram relacionados com alterações do perfil lipídico sérico e outros fatores de risco associados com doença cardiovascular. As estatinas são inibidores da síntese do colesterol utilizados no tratamento da dislipidemia. Vários polimorfismos em genes envolvidos no metabolismo intermediario de lipideos foram relacionados com diferenças na resposta a hipolipemiantes. Com a finalidade de avaliar o efeito de polimorfismos do SCARB1 sobre o perfil lipídico sérico, expressão gênica e a resposta a estatinas, foram selecionados 185 indivíduos normolipidêmicos (NL) e 147 pacientes hipercolesterolêmicos (HC). Os pacientes HC foram tratados com atorvastatina (10 mg/dia/4 semanas). DNA e RNA foram extraídos de amostras de sangue periférico. Os polimorfismos de nucleotídeo único (SNP) G4A, In5C>T e Ex8C>T foram detectados por PCR-RFLP. A expressão de RNAm do SCARB1 em células mononucleares de sangue periférico (CMSP) foi analisada por PCR em tempo real usando o gene da Ubiquitina c (UBC) como referência endógena. Nos indivíduos HC, as freqüências dos alelos raros G4A (12%), In5C>T (7%) e Ex8C>T (40%), no grupo HC, foram similares às encontradas no grupo NL (4A: 15%, In5T: 7%, e Ex8T: 35%, p>0,05). O alelo SCARB1 4A (genótipos GA + AA) foi associado com valores diminuídos de apoAI no grupo NL. O alelo In5T foi associado com maior concentração LDL-C sérico (p=0,029), em NL, e com apoB e razão apoB/apoAI elevadas (p>0,05) no grupo HC. O SNP SCARB1 Ex8C>T não foi relacionado com o perfil lipídico sérico basal, embora os portadores do genótipo Ex8CC foram associados com resposta reduzida ao tratamento com atorvastatina mostrando menor variação de colesterol total, LDL-C, apoB e razão apoB/apoAI. O SNP Ex8C>T foi associado com maior probabilidade (OR=3,1; 95% IC: 1,00-9,5; p=0,044) de ter uma resposta à atorvastatina diminuída. Os SNPs SCARB1 In5C>T e Ex8C>T estão em desequilíbrio de ligação. O haplótipo G1C5C8/G1T5C8 foi associado com concentrações basais elevadas de triglicérides e VLDL-C em NL e diminuídas de HDL-C e apoAI em HC. Os haplótipos G1C5C8/A1C5C8 e C5C8/C5C8 tiveram variação diminuída da apoB quando comparados com os outros haplótipos, G1C5C8/A1C5C8 e o diplótipo C5C8/C5C8 também apresentou uma variação reduzida da razão apoB/apoAI. Os SNPs G4A e In5C>T estão associados com diminuição da expressão gênica do SCARB1 em NL. O tratamento com atorvastatina não modifica a expressão de RNAm do SCARB1 em CMSP nos HC. Esses resultados são sugestivos de que os polimorfismos no SCARB1 estão associados com valores basais do perfil lipídico sérico e de expressão de RNAm do SCARB1, assim como de resposta à atorvastatina. / The scavenger receptor class B type I (SR-BI) mediates the selective uptake of the high density lipoprotein (HDL) cholesterol and it participates in the free cholesterol efflux to lipoprotein acceptors. HDL has an important antiatherogenic role associated with important activity in the cholesterol reverse transport. Polymorphisms in the SR-BI gene (SCARB1) have been related to variations on plasma lipoprotein profile and other risk factors for cardiovascular disease. Statins are potent inhibitors of cholesterol synthesis prescribed for treatment of the dislipidemia. Several polymorphisms in genes involved in intermediary metabolism of lipids have been related to differences in response to lowering-cholesterol drugs. In order to evaluate the effect of SCARB1 polymorphisms on serum lipids, gene expression and lipid-lowering response to atorvastatin, 185 normolipidemic (NL) and 147 hypercholesterolemic (HC) individuals were selected. HC individuals were treated with atorvastatin (10 mg/day/4 weeks). DNA and RNA were extracted from peripheric blood mononuclear cells (PBMC). SCARB1 mRNA expression was analyzed by real time PCR using ubiquitin c gene (UBC) as endogenous reference. The frequencies of the rare alleles in HC group (G4A: 12%; In5C>T: 7%, and ExC>T: 39%) were similar to those found in NL individuals (4A: 15%, In5T: 7%, and Ex8T: 35%, p>0.05). The SCARB1 4A allele (GA+AA genotypes) was associated with lower apoAI concentration in NL. The In5T allele was associated with higher serum LDL-C (p=0,029) in NL individuals, and with higher apoB and apoB/apoAI ratio (p>0,05) in HC group. SCARB1 Ex8C>T SNP was not related to serum lipids profile, however Ex8CC genotype carriers had lower variation of total cholesterol, LDL-C, apoB and apoB/apoAI ratio in response to atorvastatin. SCARB1 Ex8C>T was associated with higher chance to have a lower atorvastatin response (OR=3.1, 95% CI: 1.00-9.5; p=0.044). SCARB1 In5C>T and ExC>T were in linkage disequilibrium. G1C5C8/G1T5C8 SCARB1 haplotype was associated with higher level of triglycerides and VLDL-C in NL and lower HDL-C and apoAI levels in HC individuals. G1C5C8/A1C5C8 haplotype and C5C8/C5C8 diplotype had lower variations on apoB than the other haplotypes, and G1C5C8/A1C5C8 had also lower variation on apoB/apoAI ratio. G4A and In5C>T SNPs are associated with lower SCARB1 mRNA expression in PBMC of NL individuals. Atorvastatin therapy did not modify the expression level of the SCARB1 transcript in HC. Our results suggest that SCARB1 polymorphisms are associated with basal serum lipids profile, mRNA SCARB1 expression and atorvastatin response.

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