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Médecine traditionnelle et "médecine intégrative" à Madagascar : entre décisions internationales et applications locales / Traditional medicine and “integrative medicine” in Madagascar : between international decisions and local applicationsDidier, Pierrine 25 September 2015 (has links)
Depuis les recommandations de l'OMS de la fin des années 1970, de nombreux pays enAfrique ont mis en place des dynamiques de reconnaissance de la médecinetraditionnelle et de ses praticiens. Cette thèse s'intéresse au projet de développement dela « médecine intégrative » à Madagascar, consistant en son intégration au sein dusystème de soins officiel et conventionnel. Ce projet a pour objectif l'amélioration de lasanté des populations et passe par une double évaluation : au niveau social avecl'encadrement des activités des tradipraticiens et au niveau thérapeutique avec larecherche sur les plantes médicinales et le développement de remèdes traditionnelsaméliorés. Cette recherche est le fruit d'une démarche méthodologique qui s'appuie surdes enquêtes multi-situées, avec un terrain de recherche dans la capitale malgache et sesenvirons et avec l'ethnographie d'une localité rurale de la région Analanjirofo (côte estde Madagascar). Cette approche s'intéresse d'un côté aux tentatives d'applications desdécisions politiques en matière d'encadrement de la médecine traditionnelle et de l'autreà la pratique concrète des soins traditionnels ainsi qu'aux comportements individuels etcommunautaires face à la gestion des maux, des malheurs et de la maladie avec desétudes de cas approfondies. Cette thèse s'inscrit dans le champ de l'anthropologie de lasanté avec une orientation sur les dynamiques politiques et de développement. Unintérêt particulier est porté à la nature de la cohabitation entre praticiens (médecins,guérisseurs) se déclinant d'un simple référencement de patients à une plus rarecollaboration. Cette étude met en exergue le décalage pouvant exister entre desdécisions gouvernementales et leurs applications locales ainsi que les enjeux sociaux,politiques et économiques qui en résultent. / Following the WHO recommendations made in the late 1970s, many countries in Africahave implemented dynamics of recognition of traditional medicine and traditionalhealers. This dissertation focuses on the development of « integrative medicine » inMadagascar, consisting in its integration into the formal and conventional health caresystem. This development project, focusing on improving population's public health,requires a double evaluation: a social evaluation with the supervision of traditionalhealers' practices and a therapeutic evaluation with research on medicinal plants anddevelopment of improved traditional remedies. This research is the result of amethodological approach based on multi-located fieldworks conducted in the Malagasycapital and its surroundings and an ethnography of a rural town in the Analanjiroforegion (east coast of Madagascar). On one side, this approach focuses on the attempts ofapplication of political decisions regarding the supervision of traditional medicine andon the other side, on the real practice of traditional care as well as on individual andcommunal behaviours when facing disease, sickness, illness and misfortunes withextended case studies. This thesis contributes to the anthropology of health with a focuson political and developmental dynamics. A special emphasis is placed on the nature ofcohabitation existing between practitioners (doctors and traditional healers) going froma simple referencing of patients to a rare collaboration. This study tends to highlight thepossible gap between government decisions and local applications as well as theresulting social, political and economic issues.
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Filling flows induced by a convector in a roomPrzydrozna, Aleksandra Anna January 2018 (has links)
Over the last two centuries, there has been a continual evolution of how occupied rooms are heated, with inventors competing to design new heating devices. In particular, there is a wide range of convector types, which vary in shape, size, design, material, operating medium and application. With approximately 190 million convectors installed in the UK alone, the question arises regarding the dependencies on the efficiency of heat distribution through convector-induced filling flows. A standard approach to evaluate convector performance is based on the convector strength only, the implication being the stronger the convector the better the performance. This work has gone beyond the limits of a stereotypical assessment in pursuit of answers regarding the physics of convector-induced filling and a new objective method to evaluate the efficiency of this transient process. The ultimate goal has been to provide a deep understanding of filling and stratification induced by a convector, in order to heat rooms rapidly and effectively. An experimental facility has been designed that approximates dynamic similarity between the experimental set-up and a real-life room with a convector. In the experiments, a rectangular sectioned water tank represents a room and a saline source rectangular sectioned panel with sintered side walls provides a convector representation. Experiments have been performed in water with a saline solution to ensure high Rayleigh numbers. Diagnostic techniques involve a combination of a shadowgraph method, a dye-attenuation method, direct salinity measurements and a new application of Particle Image Velocimetry (PIV). Interesting insight into convector-induced buoyancy-driven flows has been gained. As a result, new guidelines aimed at heating rooms more rapidly and effectively have been proposed. The key outcome that can be immediately applied is that, for a given convector strength, heat distribution with height can be improved by adjusting the convector position. For instance, faster filling leading to more uniform heat distribution occurs in rooms with convectors detached from side walls, due to large-scale mixing flows in the early period of filling. Also shorter convectors relative to the room height, positioned close to the floor level, promote faster and more uniform filling. An attempt to describe the transient filling has been made and to do so statistical methods, application specific, have been developed. As a result, the empirical equations describing both the filling rates in different stages of filling and the development of stratification have been derived, which rank the governing parameters, based on their importance, as either dominant or subordinate. Two dominant parameters governing filling flows are the non-dimensional accumulation parameter B and the Rayleigh number ΔRa, which are related to the convector strength. The impact of these two parameters is constant throughout the process. The parameters accounting for the system geometry and filling time (T) are subordinate parameters. Their impact, visible in the early period, decreases as filling continues.
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Development of a new 3D beam finite element with deformable section / Développement d’un nouveau 3D poutre élément fini à section déformableGao, Sasa 05 April 2017 (has links)
Le nouvel élément de poutre est une évolution d'un élément de Timoshenko poutre avec un nœud supplémentaire situé à mi-longueur. Ce nœud supplémentaire permet l'introduction de trois composantes supplémentaires de contrainte afin que la loi constitutionnelle 3D complète puisse être utilisée directement. L'élément proposé a été introduit dans un code d'éléments finis dans Matlab et une série d'exemples de linéaires/petites contraintes ont été réalisées et les résultats sont systématiquement comparés avec les valeurs correspondantes des simulations ABAQUS/Standard 3D. Ensuite, la deuxième étape consiste à introduire le comportement orthotrope et à effectuer la validation de déplacements larges / petites contraintes basés sur la formulation Lagrangienne mise à jour. Une série d'analyses numériques est réalisée qui montre que l'élément 3D amélioré fournit une excellente performance numérique. En effet, l'objectif final est d'utiliser les nouveaux éléments de poutre 3D pour modéliser des fils dans une préforme composite textile. A cet effet, la troisième étape consiste à introduire un comportement de contact et à effectuer la validation pour un nouveau contact entre 3D poutres à section rectangulaire. La formulation de contact est dérivée sur la base de formulation de pénalité et de formulation Lagrangian mise à jour utilisant des fonctions de forme physique avec l'effet de cisaillement inclus. Un algorithme de recherche de contact efficace, qui est nécessaire pour déterminer un ensemble actif pour le traitement de contribution de contact, est élaboré. Et une linéarisation constante de la contribution de contact est dérivée et exprimée sous forme de matrice appropriée, qui est facile à utiliser dans l'approximation FEM. Enfin, on présente quelques exemples numériques qui ne sont que des analyses qualitatives du contact et de la vérification de l'exactitude et de l'efficacité de l'élément de 3D poutre proposé. / The new beam element is an evolution of a two nodes Timoshenko beam element with an extra node located at mid-length. That extra node allows the introduction of three extra strain components so that full 3D stress/strain constitutive relations can be used directly. The second step is to introduce the orthotropic behavior and carry out validation for large displacements/small strains based on Updated Lagrangian Formulation. A series of numerical analyses are carried out which shows that the enhanced 3D element provides an excellent numerical performance. Indeed, the final goal is to use the new 3D beam elements to model yarns in a textile composite preform. For this purpose, the third step is introducing contact behavior and carrying out validation for new 3D beam to beam contact with rectangular cross section. The contact formulation is derived on the basis of Penalty Formulation and Updated Lagrangian formulation using physical shape functions with shear effect included. An effective contact search algorithm is elaborated. And a consistent linearization of contact contribution is derived and expressed in suitable matrix form, which is easy to use in FEM approximation. Finally, some numerical examples are presented which are only qualitative analysis of contact and checking the correctness and the effectiveness of the proposed 3D beam element.
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Blind Detection Techniques For Spread Spectrum Audio WatermarkingKrishna Kumar, S 10 1900 (has links)
In spreads pectrum (SS)watermarking of audio signals, since the watermark acts as an additive noise to the host audio signal, the most important challenge is to maintain perceptual transparency. Human perception is a very sensitive apparatus, yet can be exploited to hide some information, reliably. SS watermark embedding has been proposed, in which psycho-acoustically shaped pseudo-random sequences are embedded directly into the time domain audio signal. However, these watermarking schemes use informed detection, in which the original signal is assumed available to the watermark detector. Blind detection of psycho-acoustically shaped SS watermarking is not well addressed in the literature. The problem is still interesting, because, blind detection is more practical for audio signals and, psycho-acoustically shaped watermarks embedding offers the maximum possible watermark energy under requirements of perceptual transparency.
In this thesis we study the blind detection of psycho-acoustically shaped SS watermarks in time domain audio signals. We focus on a class of watermark sequences known as random phase watermarks, where the watermark magnitude spectrum is defined by the perceptual criteria and the randomness of the sequence lies in their phase spectrum. Blind watermark detectors, which do not have access to the original host signal, may seem handicapped, because an approximate watermark has to be re-derived from the watermarked signal. Since the comparison of blind detection with fully informed detection is unfair, a hypothetical detection scheme, denoted as semi-blind detection, is used as a reference benchmark. In semi-blind detection, the host signal as such is not available for detection, but it is assumed that sufficient information is available for deriving the exact watermark, which could be embedded in the given signal. Some reduction in performance is anticipated in blind detection over the semi-blind detection. Our experiments revealed that the statistical performance of the blind detector is better than that of the semi-blind detector. We analyze the watermark-to-host correlation (WHC) of random phase watermarks, and the results indicate that WHC is higher when a legitimate watermark is present in the audio signal, which leads to better detection performance. Based on these findings, we attempt to harness this increased correlation in order to further improve the performance. The analysis shows that uniformly distributed phase difference (between the host signal and the watermark) provides maximum advantage. This property is verified through experimentation over a variety of audio signals.
In the second part, the correlated nature of audio signals is identified as a potential threat to reliable blind watermark detection, and audio pre-whitening methods are suggested as a possible remedy. A direct deterministic whitening (DDW) scheme is derived, from the frequency domain analysis of the time domain correlation process. Our experimental studies reveal that, the Savitzky-Golay Whitening (SGW), which is otherwise inferior to DDW technique, performs better when the audio signal is predominantly low pass. The novelty of this work lies in exploiting the complementary nature of the two whitening techniques and combining them to obtain a hybrid whitening (HbW) scheme. In the hybrid scheme the DDW and SGW techniques are selectively applied, based on short time spectral characteristics of the audio signal. The hybrid scheme extends the reliability of watermark detection to a wider range of audio signals. We also discuss enhancements to the HbW technique for robustness to temporal offsets and filtering. Robustness of SS watermark blind detection, with hybrid whitening, is determined through a set of experiments and the results are presented. It is seen that the watermarking scheme is robust to common signal processing operations such as additive noise, filtering, lossy compression, etc.
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Improving Free State matriculation results : a total quality management approach / A. MagadlaMagadla, Andiswa Antonette January 2010 (has links)
The aim of the study was to establish the possible causes of poor Grade 12 results in
physical science in South Africa and to apply a total quality management (TQM) approach
to suggest a solution. The literature study indicates that resources, preparation or subject
knowledge, commitment and support affect the quality of performance.
The research was done in one school district (cluster). Following the literature study a
questionnaire was distributed to 150 science teachers from 31 schools and the response
rate was 73% (113 responses). The questionnaire tested the respondents' perception on
the availability of resources and the support received by them, the support given to
learners and their level of preparation and subject knowledge. From this, as well as from
the biographical information from the questionnaire, certain conclusions were made about
the reasons for poor performance of learners in science examinations.
It could be concluded from the analysis of the results that limited support to teachers and
support to learners are important factors contributing to a poor Grade 12 pass rate. The
pass rate also correlates positively with experience levels of teachers. Although 39% of
teachers are unqualified or under-qualified, no significant correlation could be found
between pass rate and level of qualification. Analysis of the effect of commitment on pass
rate was inconclusive. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2011.
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Improving Free State matriculation results : a total quality management approach / A. MagadlaMagadla, Andiswa Antonette January 2010 (has links)
The aim of the study was to establish the possible causes of poor Grade 12 results in
physical science in South Africa and to apply a total quality management (TQM) approach
to suggest a solution. The literature study indicates that resources, preparation or subject
knowledge, commitment and support affect the quality of performance.
The research was done in one school district (cluster). Following the literature study a
questionnaire was distributed to 150 science teachers from 31 schools and the response
rate was 73% (113 responses). The questionnaire tested the respondents' perception on
the availability of resources and the support received by them, the support given to
learners and their level of preparation and subject knowledge. From this, as well as from
the biographical information from the questionnaire, certain conclusions were made about
the reasons for poor performance of learners in science examinations.
It could be concluded from the analysis of the results that limited support to teachers and
support to learners are important factors contributing to a poor Grade 12 pass rate. The
pass rate also correlates positively with experience levels of teachers. Although 39% of
teachers are unqualified or under-qualified, no significant correlation could be found
between pass rate and level of qualification. Analysis of the effect of commitment on pass
rate was inconclusive. / Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2011.
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Virtuell ljussättning inom Augmented Reality : Semi-automatisk ljushantering för ökad upplevd realism / Virtual Lighting in Augmented Reality : A Semi-automatic approach for enhanced realismLundqvist, Oscar January 2018 (has links)
Denna studie avser att undersöka hur ökad upplevd realism kan uppnås i Augmented Reality (AR) applikationer, genom ökad användarinteraktion med utvalda, virtuella ljusparametrar. Den teoretiska referensramen omfattas av övergripande teorier kopplade till AR men även mer djupgående forskning kring virtuell ljussättning och ljusparametrar. I en domän där automatiserade lösningar för virtuell ljussättning dominerar, ämnar denna studie påvisa bristerna med automatisk hantering av virtuellt ljus och istället motivera en lösning av semi-automatisk karaktär. Studien avser även att söka svaret på vilken utav utvalda ljusparametrar som haft störst inverkan i åtagandet att öka upplevd realism. Med Action Design Research (ADR) som huvudsaklig forskningsmetod, utvecklas ett grundläggande tillägg till en befintlig AR applikation i nära samarbete med företaget Neava. Applikationstillägget möjliggör manuell justering av det virtuella ljusets riktning, intensitet och färgtemperatur. Applikationstillägget testas sedan av befintliga användare under observation, därefter besvarar användaren en enkät grundad i testet, där jämförelse mellan befintlig applikation och applikationstillägg är temat. Insamlade observations- och enkätdata sätts i centrum för analys med avsikt att förklara relevanta fenomen och mönster, kopplade till upplevd realism. Studien finner att det utvecklade applikationstillägget i 90% av fallen genererar en ökad upplevd realism. Vidare finner studien att den virtuella ljusparameter som bidragit mest till ökad realism är ljusriktning, efterföljt av ljusintensitet och den minst bidragande visar sig vara färgtemperatur. De slutsatser som dras i studien formuleras och presenteras avslutningsvis i form av en oberoende lista designprinciper. / The purpose of this study is to examine how an improved level of experienced realism could be achieved in Augmented Reality (AR) applications, by allowing increased user interaction with a chosen set of virtual lighting parameters. The theoretical foundation of this thesis is both concerned with surveys and literature reviews of AR in general but also virtual lighting and lighting parameters to a significant extent. In contrast to the majority of previous research, where estimating and managing virtual lighting is done automatically, this study suggests that a semi-automatic approach might be better suited in delivering improved levels of experienced realism. Through the course of this thesis it is also intended to evaluate which of the chosen lighting parameters that has had the greatest impact in achieving improved experienced realism. Action Design Research (ADR) is applied as the core research methodology and in collaboration with the company Neava, an addon for an existing AR application is developed. This addon enables manual adjustments of virtual light direction, intensity and color temperature. The addon is tested by users of the existing application under observation, afterwards the testers answer a brief survey concerning the test, where a comparison between existing application and addon is made. Data gathered from both the observations and the surveys are then subjects of an analysis, where different phenomena and findings regarding improved experienced realism is the focus. The study finds that roughly 90% of the testers did indeed experience an improved level of realism, using the semi-automatic addon. Furthermore the study finds that the virtual lighting parameter most effective in achieving this is light direction, followed by light intensity and least effective in the effort is color temperature. The conclusions made of this study are finally presented in the form of a list of design principles.
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Aperfeiçoamento do algoritmo algébrico sequencial para a identificação de variações abruptas de impedância acústica via otimização / Identification of rough impedance profile using an improved acoustic wave propagation algorithmFilipe Otsuka Taminato 21 February 2014 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Neste trabalho são utilizados a técnica baseada na propagação de ondas acústicas e o
método de otimização estocástica Luus-Jaakola (LJ) para solucionar o problema inverso
relacionado à identificação de danos em barras. São apresentados o algoritmo algébrico
sequencial (AAS) e o algoritmo algébrico sequencial aperfeiçoado (AASA) que modelam o
problema direto de propagação de ondas acústicas em uma barra. O AASA consiste nas
modificações introduzidas no AAS. O uso do AASA resolve com vantagens o problema de
identificação de danos com variações abruptas de impedância. Neste trabalho são obtidos,
usando-se o AAS-LJ e o AASA-LJ, os resultados de identificação de cinco cenários de danos.
Três deles com perfil suave de impedância acústica generalizada e os outros dois abruptos.
Além disso, com o objetivo de simular sinais reais de um experimento, foram introduzidos
variados níveis de ruído. Os resultados alcançados mostram que o uso do AASA-LJ na
resolução de problemas de identificação de danos em barras é bastante promissor, superando
o AAS-LJ para perfis abruptos de impedância. / In this work the techniques based on the wave propagation approach and the Luus-
Jaakola optimization method to solve the inverse problem of damage identification in bars are
applied. The sequential algebraic algorithm (SAA) and the improved sequential algebraic
algorithm (ISAA) that model the direct problem of acoustic wave propagation in bars are
presented. The ISAA consists on modifications of the SAA. The use of the ISAA solves with
advantages the problem of damage identification when the generalized acoustical impedance
variations are abrupt. In this work the results of identification of five damage scenarios are
obtained using the SAA and the ISAA. Three of them are smooth impedance profiles and the
other two are rough ones. Moreover, to simulate signals obtained experimentally, different
noise levels were introduced. It is shown that using the ISAA-LJ in solving problems of
damage identification in bars is quite promising, furnishing better results than the SAA-LJ,
specially when the impedance profiles are abrupt.
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Aperfeiçoamento do algoritmo algébrico sequencial para a identificação de variações abruptas de impedância acústica via otimização / Identification of rough impedance profile using an improved acoustic wave propagation algorithmFilipe Otsuka Taminato 21 February 2014 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / Neste trabalho são utilizados a técnica baseada na propagação de ondas acústicas e o
método de otimização estocástica Luus-Jaakola (LJ) para solucionar o problema inverso
relacionado à identificação de danos em barras. São apresentados o algoritmo algébrico
sequencial (AAS) e o algoritmo algébrico sequencial aperfeiçoado (AASA) que modelam o
problema direto de propagação de ondas acústicas em uma barra. O AASA consiste nas
modificações introduzidas no AAS. O uso do AASA resolve com vantagens o problema de
identificação de danos com variações abruptas de impedância. Neste trabalho são obtidos,
usando-se o AAS-LJ e o AASA-LJ, os resultados de identificação de cinco cenários de danos.
Três deles com perfil suave de impedância acústica generalizada e os outros dois abruptos.
Além disso, com o objetivo de simular sinais reais de um experimento, foram introduzidos
variados níveis de ruído. Os resultados alcançados mostram que o uso do AASA-LJ na
resolução de problemas de identificação de danos em barras é bastante promissor, superando
o AAS-LJ para perfis abruptos de impedância. / In this work the techniques based on the wave propagation approach and the Luus-
Jaakola optimization method to solve the inverse problem of damage identification in bars are
applied. The sequential algebraic algorithm (SAA) and the improved sequential algebraic
algorithm (ISAA) that model the direct problem of acoustic wave propagation in bars are
presented. The ISAA consists on modifications of the SAA. The use of the ISAA solves with
advantages the problem of damage identification when the generalized acoustical impedance
variations are abrupt. In this work the results of identification of five damage scenarios are
obtained using the SAA and the ISAA. Three of them are smooth impedance profiles and the
other two are rough ones. Moreover, to simulate signals obtained experimentally, different
noise levels were introduced. It is shown that using the ISAA-LJ in solving problems of
damage identification in bars is quite promising, furnishing better results than the SAA-LJ,
specially when the impedance profiles are abrupt.
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Extrusion- spheronization of pharmaceutical products : system for the delivery of active ingredients which are poorly soluble by oral route / Extrusion-sphéronisation de produits pharmaceutiques : système de délivrance des principes actifs peu solubles par voie oraleNguyen, Thi Trinh Lan 28 June 2017 (has links)
L'amélioration de la dissolution des médicaments peu solubles présente de nombreux défis.Dans cette thèse, un procédé d'extrusion-sphéronisation a été étudié en profondeur pour améliorer la dissolubilité du médicament avec une formulation de nano-émulsion. Le but du travail de thèse est de décrire les propriétés et les procédés de fabrication de minigranules permettant d'augmenter la solubilité des principes actifs peu solubles dans l'eau et donc d‘améliorer leur biodisponibilité lors de l'administration par voie orale, pour deux modèles de molécules différentes qui sont l‘acide folique (vitamine peu soluble dans l'eau) et le kétoprofène (anti-inflammatoire non stéroïdien qui présente une solubilité limitée dans les fluides gastriques à cause de son pKa (classe II dans le système de classification biopharmaceutique – BCS, ayant une action anti-inflammatoire, antalgique et antipyrétique). Cette étude décrit la préparation par extrusion-sphéronisation, caractérisation et étude de dissolution in vitro d'acide folique et de pastilles de kétoprofène revêtues de Acryl-EZE®, Advantia® Performance dans un minicoatère à lit fluidisé. Les résultats des essais ont montré la faisabilité de la préparation de pastilles enrobées entériques contenant un AINS et que, en revêtant le système multiparticulaire avec Acryl-EZE® 93A92545 et Advantia® Performance190024HA49 à un gain pondéral de 17,5%, 12,0%, respectivement, du médicament à partir des pastilles peuvent être obtenus. Les résultats des essais de dissolution ont indiqué que dans un milieu acide, le revêtement de film a entraîné un retard dans la libération du médicament, alors qu'aucun retard n'a été observé dans un milieu tampon à pH 6,8. / Improvement in dissolution of poorly soluble drugs has many challenges.In this thesis, an extrusion-spheronization process was thoroughly studied forimproving dissolubility of drug with nano-emulsion formulation.The aim of the thesis work is to describe the properties and manufacturing processes ofpellets to increase the solubility of poorly soluble active ingredients in water and thus improvetheir bioavailability when administered orally: folic acid (water-insoluble vitamin) andketoprofen (Non-steroidal anti-inflammatory, having anti-inflammatory, analgesic andantipyretic action, class II in the Biopharmaceutical Classification System).This study describes the preparation by extrusion-spheronization, characterisation andin vitro dissolution study of folic acid and ketoprofen pellets. Ketoprofen pellets coated withAcryl-EZE®, Advantia® Performance in a fluid-bed minicoater. The results of the tests showedthe feasibility of the preparation of enteric-coated pellets containing a NSAID and that bycoating the multiparticulate system with either 17.5% Acryl-EZE® 93A92545 or with 12%Advantia® Performance 190024HA49 weight gain, an enteric release of the drug from thepellets can be obtained. The results of dissolution testing indicated that in acidic media, entericfilm coating resulted in a delay in the release of the drug, while no delay was observed in pH6.8 buffer media.
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