Comunicarea este o scurtă istorie a medicinei românești de pănă la Regulamentul Organic, li este inedită prin faptul că nominalizează medicii domnitorilor români , începând din epoca lui Ștefan cel ...Mare și ajungând până în 1814, când avem prima organizare a unei Case a medicilor ( documentul din 14 august 1814, emis de Scarlat vodă Callimachi.
Conferință ținută la Societatea studenților în medicină
Alexandru Mircea, voievodul Țării Românești, întărește lui Neagoe logofăt ocini la Brădășani și Manița, în urma unor judecăți
Sigiliu: timbrat
Alexandru Mircea, the voivode of Wallachia, reinforces ...to Neagoe the fiancee in Broot and Manița, following judgments.
Alexandru Mircea, voievodul Țării Românești, întărește lui Neagoe logofăt ocini la Brădășani și Manița, în urma unor judecăți
Sigiliu: timbrat
Les canaux anioniques ont toujours été sous-estimés par rapport aux canaux cationiques principalement en raison des difficultés à caractériser leurs identités moléculaires et par l'absence ...d'inhibiteurs sélectifs puissants. C’est une classe comportant une grande hétérogénéité et une importante complexité comprenant entre autres le CFTR activé par l’AMP cyclique, les anoctamines activées par le calcium intracellulaire et les canaux VRAC activés lors d’un gonflement cellulaire. L’identité moléculaire d’une protéine essentielle aux courants ioniques déclenchés par le gonflement cellulaire a été découverte en 2014, permettant de pouvoir enfin investiguer le fonctionnement et le rôle de ces canaux. Dans une première partie, nous avons démontré l’absence de spécificité des inhibiteurs des principaux canaux chlorures. Cette étude met en exergue le besoin de développer de nouveaux inhibiteurs permettant de discriminer les différents canaux chlorures, mais aussi la nécessité de coupler l’approche pharmacologique à une approche génétique. Dans une deuxième partie, nous avons mis en évidence la perméabilité des canaux anioniques sensibles au gonflement cellulaire au glutathion, principal antioxydant cellulaire. Nos résultats suggèrent donc que les canaux VRAC pourraient être impliqués dans la régulation du stress oxydatif. Dans la troisième partie de ma thèse, nous avons montré que le facteur de croissance TGFβ1 stimule l’ouverture des canaux anioniques sensibles au gonflement cellulaire. Cette activation s’accompagne d’une perte de glutathion et d’une accumulation intracellulaire d’espèces réactives de l’oxygène. Cette dernière est à l’origine d’une transition épithélio-mésenchymateuse des cellules rénales. L’inhibition pharmacologique ainsi que la répression génétique des canaux VRAC réduit significativement les effets du TGFβ1. Enfin dans la dernière partie, nous avons caractérisé le rôle des canaux anioniques sensible au gonflement cellulaire dans la sécrétion de facteurs pro-inflammatoires par les macrophages stimulés par un choc hypotonique. En collaboration, nous avons montré que le blocage de la régulation du volume cellulaire, sous le contrôle de ces canaux, entraine une inhibition de l’activation de l’inflammasome et donc de la sécrétion des facteurs pro-inflammatoires. Bien que les mécanismes de signalisation cellulaire restent à déterminer, ces travaux mettent en lumière l’importance des canaux anioniques sensibles au gonflement cellulaire dans la transition épithéliomésenchymateuse et l’inflammasome. Il apparait que ces canaux pourraient être des cibles thérapeutiques prometteuses dans un certain nombre de pathologies et qu’il est primordial de poursuivre les investigations dans ce domaine.
Anion channels have always been underestimated compared to cationic channels mainly because of the difficulty in characterizing their molecular identities and the absence of potent selective inhibitors. It is a class with great heterogeneity and complexity, including CFTR activated by cAMP, anoctamines activated by intracellulaire calcium and VRAC channels activated by cell swelling. The molecular identity of an essential protein to the ionic currents triggered by cell swelling was discovered in 2014, allowing the scientist community to investigate the role of these channels. In a first part, we highlighted the lack of specificity of the inhibitors of different chloride channels. This study shed lights on the need to develop new inhibitors to discriminate the different chloride channels, but also the need to couple the pharmacological approach to a genetic approach. In a second part, we have demonstrated the glutathione permeability of Volume Regulated Anion Channels. Our results therefore suggest that VRAC channels might be involved in the regulation of oxidative stress as glutathione is the main antioxidant within the cell. In the third part of my thesis, we have shown that TGFβ1 growth factor stimulates the opening of Volume Regulated Anion Channels which is correlated with both a loss of glutathione and an intracellular accumulation of reactive oxygen species. The latter is at the origin of an epitheliomesenchymal transition of renal cells. The pharmacological inhibition as well as the genetic repression of the VRAC channels significantly reduces the effects of TGFβ1. Finally, in the last part, we characterized the role of Volume Regulated Anion Channels in the secretion of pro-inflammatory factors by macrophages stimulated by hypotonic shock. In collaboration, we have shown that blocking the regulation of cell volume, under the control of these channels, leads to an inhibition of the inflammasome and therefore of the secretion of pro-inflammatory factors. Although cell signaling mechanisms remain to be determined, this work highlights the importance of VRAC in the epithelial-mesenchymal transition and inflammasome. It appears that these channels could be promising therapeutic targets in a certain number of pathologies and that it is essential to continue the investigations in this field.
Ce travail de thèse rentre dans le cadre du développement de modèles multi‐échelles de simulation de colonne d’absorption gaz‐liquide pour des applications de captage de CO2 en vue d’optimiser leur ...design. Il est le fruit d’une collaboration entre IFP Énergies nouvelles et l’Institut de Mécanique des Fluides de Toulouse. Les colonnes à garnissages représentent une technologie essentielle aux applications d’absorption gaz‐liquide. Dans les procédés de captage de CO2 aux amines, le solvant liquide s’écoule sur les parois du garnissage, idéalement sous forme de film ruisselant mouillant toute la surface disponible, le gaz, en régime turbulent, venant le cisailler à contre‐courant de manière à promouvoir un transfert de CO2 de la phase gaz vers la phase liquide. Un écoulement le plus homogène possible permet d’avoir les meilleures performances de transfert. Toutefois, l’expérience montre que des maldistributions, notamment de la phase liquide, peuvent apparaître même en cas de bonnes distributions en entrée de colonne. La distribution du liquide est régie par un phénomène de « dispersion » dont l’étude et la modélisation représentent le principal objet de cette thèse. Pour ce faire, ce travail de thèse s’appuie sur des travaux expérimentaux, réalisés sur une installation d’IFPEN à Lyon, et sur des travaux numériques réalisés dans l’équipe Interface de l’IMFT. Le premier axe de l’étude abordé a ainsi consisté en l’acquisition de données originales de distribution de liquide en partant d’une configuration d’alimentation sous forme d’un jet central en tête de colonne et ce pour deux types de garnissages métalliques : un garnissage structuré, le Mellapak 250.X et un garnissage vrac, l’IMTP. 40. La méthode de tomographie gamma a été mise en œuvre afin de mesurer l’atténuation d’un flux photonique par le liquide en mouvement ce qui permet d’établir des cartes de rétention locale de liquide sur une section de colonne. Les profils de rétention résultants ont été ensuite exploités afin de caractériser la dispersion de liquide dans le système pour des régimes d’écoulement allant des plus faibles aux plus fortes interactions gaz‐liquide. Ces résultats ont permis de développer un modèle simple d’advection diffusion faisant appel à un paramètre hydrodynamique clé qui est le « coefficient de dispersion », qui reproduit bien l’étalement du jet de liquide. Dans le cas du garnissage Mellapak 250.X nous avons pu mettre en évidence une dispersion qui est régie essentiellement par la géométrie du milieu.
This work is done within the framework of collaboration between IFPEN and l’Institut de Mécanique des Fluides de Toulouse (IMFT). It takes place in the general context of optimization of industrial gas‐liquid packed columns dedicated to CO2 capture using multi‐scale simulation approach of hydrodynamics and transfer. The main objective of this study is to develop predictive model for liquid dispersion in two‐phase flows in packed beds operating in the counter‐current mode. This model will help simulate the flow at the macro‐scale of a packed column. Packed columns are widely used for gas/liquid absorption processes since they generate subsequent exchange surface between phases with limited pressure drop. In the particular case of amine process, the two‐phase flow in the packing consists in thin trickling liquid films sheared by counter‐current gas flow that circulates in communicating tortuous channels. It is widely recognized that homogeneous flow ensures good separation performances. This is far from being the case at industrial scale since maldistributions, especially for liquid phase, do occur even with optimized liquid and gas distributors in the column inlets. Liquid distribution results from “dispersion” phenomenon which modelling is not fully handled in literature. Prediction of liquid dispersion has been the main objective of this Ph.D. research. This study is based upon two main approaches: an experimental study carried out using a 40 cm in diameter column operating in IFPEN (Lyon) and a numerical study carried out in Interface team in IMFT. The first part of this research focused on measuring spatial distribution of liquid hold‐up over different sections of the packed bed using a gamma ray tomography system. In order to focus into liquid dispersion phenomenon, a point source liquid feeding configuration was considered. Hold‐up maps obtained from photonic flux attenuation measurements were then used to characterize liquid dispersion from a source point for both packings (Mellapak 250.X and IMTP. 40) using a relatively simple advection‐diffusion model.
The design loads depend on the grain moisture content in a cylindrical storage structure for corn Öztürk, T., Ondokuz Mayıs Univ., Faculty of Agriculture, Samsun (Turkey). Div. of Farm Structures and Irrigation; Esen, B., Ondokuz Mayıs Univ., Faculty of Agriculture, Samsun (Turkey). Div. of Farm Structures and Irrigation; Kibar, H., Ondokuz Mayıs Univ., Faculty of Agriculture, Samsun (Turkey). Div. of Farm Structures and Irrigation
Anadolu tarım bilimleri dergisi (Online),
(2008), Letnik:
23, Številka:
2
Journal Article
Recenzirano
In this study, design loads depend on the grain moisture content in a cylindrical storage structure for corn which has system of free flow steel construction and 1000 ton storage capacity were ...investigated. In the research, the corn varieties of Karadeniz Yıldızı, Cin, TTM-813, Akpınar and Şeker were used. Firstly, the physical and mechanical properties such as bulk density, true density, angle of internal friction, ratio of pressure, static coefficient of friction of corn grains were determined. Load analysis was then calculated using software program of MS Visual Basic 6.0. The results of research show that increase of the grain moisture content caused decrease at design loads of storage system in the variation ratios from 19.33 % to 30.57 %. The decrease ratios of design load were occurred depend on moisture content and variety.
Bu araştırmada serbest akış sistemine sahip çelik konstrüksiyon 1000 ton depolama kapasiteli silindirik bir mısır depolama yapısındaki projeleme yükleri tane nem kapsamındaki değişime bağlı olarak incelenmiştir. Çalışmada mısır çeşidi olarak Karadeniz Yıldızı, Cin, TTM-813, Akpınar ve Şeker mısır çeşitleri kullanılmıştır. Mısır tanelerinin önce birim hacim ağırlık, özgül ağırlık, içsel sürtünme açısı, basınç oranı,statik sürtünme katsayısı gibi fiziksel ve mekaniksel özellikleri saptanmış, daha sonra hazırlanan MS Visual Basic 6.0 yazılım programıyla depo yük analizleri yapılmıştır. Araştırma sonucunda tane nem kapsamındaki artışın (% 8-14),depo sistem projeleme yüklerinde % 19.33 ile % 30.57 arasında değişen azalmaya neden olduğu, projeleme yükündeki azalma oranlarının nem kapsamına ve çeşide bağlı olarak değiştiği saptanmıştır.
The design parameters of storage load in the cylindrical storage structures for hazelnut Öztürk, T., Ondokuz Mayıs Univ., Faculty of Agriculture, Samsun (Turkey). Div. of Farm Structures and Irrigation; Kibar, H., Ondokuz Mayıs Univ., Faculty of Agriculture, Samsun (Turkey). Div. of Farm Structures and Irrigation
Anadolu tarım bilimleri dergisi (Online),
(2008), Letnik:
23, Številka:
2
Journal Article
Recenzirano
In this study, design loads depend on the hazelnut moisture content in a cylindrical storage structure for hazelnut which has system of free flow, steel construction and 1200 ton storage capacity ...were investigated. In the research, tombul, badem, mincane, çakıldak, sivri as huzelnut varieties were used. Firstly, the physical and mechanical properties such as bulk density, true density, angle of internal friction, ratio of pressure, static coefficient of friction of hazelnut grains were determined. Load analysis was then made using software program of MS Visual Basic 6.0.The results of research show that increase of the grain moisture content caused decrease at design loads of storage system. The decrease ratios of design load were occurred depend on moisture content and variety.
Bu araştırmada serbest akış sistemine sahip çelik konstrüksiyon 1200 ton depolama kapasiteli silindirik bir fındık depolama yapısındaki projeleme yükleri fındık nem kapsamındaki değişime bağlı olarak incelenmiştir. Çalışmada fındık çeşidi olarak tombul, badem, mincane, çakıldak, sivri kullanılmıştır. Fındık tanelerinin önce serbest birim hacim ağırlık, özgül ağırlık, içsel sürtünme açısı, statik sürtünme katsayısı gibi fiziksel ve mekanik özellikleri saptanmış sonra hazırlanan MS Visual Basic 6.0 yazılım programıyla depo yük analizleri yapılmıştır. Araştırma sonucunda tane nem kapsamındaki artışın depo sistem projeleme yüklerinde azalmaya neden olduğu, projeleme yükündeki azalma oranlarının nem kapsamına ve çeşide bağlı olarak gerçekleştiği saptanmıştır.
Résumé. — Caractérisé par le plus grand gabarit fluvial au monde, l'espace de navigation du Saint-Laurent et des Grands Lacs est le théâtre de trois types de navigation (intérieure, fluvio-maritime ...et océanique). Il jouit d'un statut juridique très original, reposant uniquement sur des accords bilatéraux et sur des conventions signées à l'échelle mondiale, ce qui laisse chaque pays riverain entièrement souverain sur son propre territoire, tout en lui permettant de poursuivre ses propres politiques, par exemple sur la question des péages.
Mais cet axe international est menacé par la baisse des trafics, notamment pour ce qui est du minerai de fer et des produits agricoles, tandis que les révolutions technologiques en cours sur les océans et sur le continent rendent difficile l'avenir du port de Montréal pour le trafic des conteneurs. Ces quelques exemples soulignent l'importance des analyses de type systémique, et conduisent à montrer que seuls les gouvernements régionaux, comme celui du Québec, peuvent mettre en œuvre les outils indispensables de réflexion collective et d'intervention en vue de la sauvegarde des intérêts d'un tel espace de navigation international.
Abstract : The Great Lakes/St-Lawrence System presents the greatest infrastructure sizes available for inland navigation and it is used by lakers, ocean-going lakers, and sea vessels. It is characterized by a very original juridical status, based only on bilateral treaties and world commerce conventions. Each border country keeps its total sovereignty on its own territory, and is able to go on with its own policies, for example on the problem of tolls.
But this international axis in threatened by diminishing traffics, especialliy on iron ore and agricultural products, while the present technological changes on the ocean as on the continent may jeopardize the future of the container traffic in the port of Montreal. These few examples show the importance of systemic approaches in this fiels, and lead to the conclusion that only régional governments, like the Quebec one, are able to set up thge necessary tools for reflexion and action taking care of the interests of suchs an international axis.