Mon travail cherche à mettre en valeur la richesse de la Scuola Napoletana du XVIIème siècle (qui prend vie après les deux séjours du Caravage à Naples, entre 1606 et 1610). L'art napolitain est injustement sous-estimé ; la première moitié du Seicento est pourtant extrêmement importante puisque Naples est le seul centre artistique qui continue à considérer le caravagisme comme une force vitale de la peinture, et ce jusqu'en 1656 (année de la Grande Pestequi emporte avec elle les derniers peintres d'"origine" caravagesque). Je mets donc en exergue la période méridionale du Caravage (qui est trop souvent délaissée par rapport à sa période romaine), ainsi que l'extrême diversité des peintres caravagesques qui composent le milieu artistique napolitain, unis par une passion commune pour le langage du Caravage mais dont l'expression artistique intègre peu à peu d'autres influences. Le caravagisme méridional se distingue par son polymorphisme et par la diversité des influences extérieures avec lesquelles les artistes enrichissent leur caravagisme originel : si les premiers naturalistes (tels que Battistello) restent toujours fidèles au Maître, nombreux sont ceux qui suivront le courant ribéresque (Ribera, Fracanzano, le Maître de l'Annonce aux Bergers...) qui se caractérisepar sa portée sociale. Mais, parallèlement, certains peintres tissent des liens entre caravagisme et classicisme (Stanzione, Guarino), tandis que d'autres se focalisent sur un caravagisme narratif (Artemisia Gentileschi est réputée pour son talent de storyteller) ; dans le domaine chromatique, de nombreux artistes (dont Pietro Novelli ou Ribera) succombent au néovénétisme et au vandyckianisme en vogue à partir des années 1630. Enfin, le caravagisme se fait plus raffiné avec Bernardo Cavallino, qui apparaît comme un précurseur du goût rococo, tandis que l'oeuvre de Mattia Preti oscille entre caravagisme et baroque. / The aim of this work is to emphasize the richness of the Scuola Napoletana in the 17th Century (after it came to life following Caravaggio†s two stays in Naples between 1606 and 1610). Neapolitan art does not get the appreciation it deserves, and yet the first half of the Seicento was an extremely important period as Naples was the only major artistic centre where Caravaggism was still a driving force of painting, and would do so until 1656 (the year of the Great Plague that wiped out the last "original" Caravaggesque painters). I am therefore emphasizing Caravaggio†s Southern period, which is all too often neglected as compared to his Roman period, as well as the great diversity of Caravaggesque painters making up the artistic milieu in Naples, united by a shared passion for Caravaggio's language but progressively incorporating other influences into their artistic expression. Southern Caravaggism stands out because of its polymorphism and the highly diverse outer influences with which these artists enhance their original Caravaggism: while the first naturalists, such as Battistello, are always true to the Master, many will follow into Ribera's footsteps (Ribera,Fracanzano, the Master of the Announcement to the Shepherds...) and adopt a more socially oriented stance. At the same time, some painters draw links between Caravaggism and Classicism (Stanzione, Guarino), while others focus on narrative Caravaggism (Artemisia Gentileschi is famed for the storytelling talent). In the field of colour, many artists (including Pietro Novelli and Ribera) yield to the Neo-venetism or Vandyckianism that were fashionable as of the 1630†s. Finally,Caravaggism becomes more refined with Bernardo Cavallino, who appears to be a precursor of Rococo taste, while Mattia Preti balances on the verge between Caravaggism and Barocco.

Na busca por espécies vegetais com atividade antileishmania, selecionaram-se, para o estudo, duas espécies bem conhecidas da família Asteraceae: Artemisia annua L. e Bidens pilosa L. Ambas são reconhecidamente utilizadas na medicina popular, como antiprotozoárias. Apesar de terem sido amplamente estudadas em diversos aspectos, alguns permaneceram inexplorados, até o momento, e foram abordados, neste trabalho. As duas espécies foram analisadas quanto aos aspectos químico e biológico de extratos (hidroetanólico e infuso) e frações orgânicas selecionados, em função da atividade antileishmania in vitro, frente às formas promastigotas de Leishmania amazonensis. Os extratos foram obtidos a partir de órgãos vegetais, em estados de conservação diferentes (in natura, droga) e coletados em fenofases distintas. Extratos e frações orgânicas das espécies estudadas mostraram promissora atividade antileishmania in vitro e baixo nível de citotoxicidade in vitro em células epiteliais humanas (HEP-2). No estudo químico dos extratos e frações bioativos, realizaram-se análises qualitativas e/ou quantitativas de terpenos, flavonóides e de marcadores específicos (artemisinina, quercetina e rutina), avaliando-se a variação da composição dos mesmos, nas diferentes fenofases consideradas. Discutiram-se as possíveis relações existentes entre a composição química e a atividade biológica verificada. Aspectos inéditos do estudo morfoanatômico de partes aéreas de A. annua foram descritos. / Plants are potential sources of new antileishmanial drugs. Two well-known antiprotozoal species were selected, from the Asteraceae family, for this study: Artemisia annua L and Bidens pilosa L. Despite the traditional and scientific accumulated knowledge, some aspects were not investigated before and were the subject of this work. Several extracts (infusions and ethanol 96 °GL) and selected fractions from both species were evaluated according to the different parameters, such as: plant organs and/or parts, growth stages and drying state of starting materials (fresh, drug). Fractions were selected among those more active against promastigotes of Leishmania amazonensis. Ethanol extracts and their fractions showed a high level of in vitro antileishmanial activity and a low cytotoxicity on epithelial human cells (HEP-2). Qualitative and/or quantitative analysis of extracts and fractions were performed for terpenes, flavonoids and selected markers (artemisinin, quercetin and rutin) in order to characterize them and evaluate variations during the different growth stages. Correlations of the chemical composition and the biological activity were discussed. The main anatomical characters of the aerial parts of A. annua were described for the first time and illustrated by photomicrographs.

Na busca por espécies vegetais com atividade antileishmania, selecionaram-se, para o estudo, duas espécies bem conhecidas da família Asteraceae: Artemisia annua L. e Bidens pilosa L. Ambas são reconhecidamente utilizadas na medicina popular, como antiprotozoárias. Apesar de terem sido amplamente estudadas em diversos aspectos, alguns permaneceram inexplorados, até o momento, e foram abordados, neste trabalho. As duas espécies foram analisadas quanto aos aspectos químico e biológico de extratos (hidroetanólico e infuso) e frações orgânicas selecionados, em função da atividade antileishmania in vitro, frente às formas promastigotas de Leishmania amazonensis. Os extratos foram obtidos a partir de órgãos vegetais, em estados de conservação diferentes (in natura, droga) e coletados em fenofases distintas. Extratos e frações orgânicas das espécies estudadas mostraram promissora atividade antileishmania in vitro e baixo nível de citotoxicidade in vitro em células epiteliais humanas (HEP-2). No estudo químico dos extratos e frações bioativos, realizaram-se análises qualitativas e/ou quantitativas de terpenos, flavonóides e de marcadores específicos (artemisinina, quercetina e rutina), avaliando-se a variação da composição dos mesmos, nas diferentes fenofases consideradas. Discutiram-se as possíveis relações existentes entre a composição química e a atividade biológica verificada. Aspectos inéditos do estudo morfoanatômico de partes aéreas de A. annua foram descritos. / Plants are potential sources of new antileishmanial drugs. Two well-known antiprotozoal species were selected, from the Asteraceae family, for this study: Artemisia annua L and Bidens pilosa L. Despite the traditional and scientific accumulated knowledge, some aspects were not investigated before and were the subject of this work. Several extracts (infusions and ethanol 96 °GL) and selected fractions from both species were evaluated according to the different parameters, such as: plant organs and/or parts, growth stages and drying state of starting materials (fresh, drug). Fractions were selected among those more active against promastigotes of Leishmania amazonensis. Ethanol extracts and their fractions showed a high level of in vitro antileishmanial activity and a low cytotoxicity on epithelial human cells (HEP-2). Qualitative and/or quantitative analysis of extracts and fractions were performed for terpenes, flavonoids and selected markers (artemisinin, quercetin and rutin) in order to characterize them and evaluate variations during the different growth stages. Correlations of the chemical composition and the biological activity were discussed. The main anatomical characters of the aerial parts of A. annua were described for the first time and illustrated by photomicrographs.

The anti-inflammatory properties of four medicinal plants were investigated. These plant extracts were subjected to screening for their possible effects as antioxidative, analgesic, and anti-inflammatory agents. In the antioxidant activity, the Plantago lancelota extracts resulted in an IC50 value of 0.4 mg/mL compared to the positive control quecertin with IC50 0.04 mg/mL Plantago lanceolata inhibited COX-2 activity with IC50 values of 0.41 mg/mL. However, the COX-1 inhibition indicated an IC50 of 68.99 mg/mL. The lipoxygenase assay indicated that Plantago lanceolata was the most active plant species with an IC50 value of 4.86 mg/mL compared to the positive control (quecertin) with an IC50<2mg/mL. The nitric oxide assay of the plant extracts indicates a dose-dependent activity of our plant extracts. Likewise the cell viability result indicated a good activity at dose 100 mg/mL. / Life and Consumer Sciences / M. Sc. (Life Sciences)

The orans, although a gesture with a long ‘pagan’ past, was easily adopted by Christians for its symbolic meanings of prayer and piety and quickly attained a number of other more nuanced meanings as it was refined and reused. By restricting the scope of this thesis to the orans in the Christian catacombs of Rome, it becomes possible to approach the figure from a multi-directional perspective, not merely concerned with what the gesture meant to the Christian, but with its literary and material pedigrees, its transition to Christian art, and its cultural significance. To this end, chapter one examines ‘pagan’ precursors of the Christian orans through an examination of coins, sculptures, inscriptions, and reliefs, as well as by looking at the two figures whose appearance most influences that of the orans – the goddess Pietas, and the Artemisia-Adorans funerary portrait type. Chapter two addresses the importance of the orans in the Christian literary community, and examines not only the actual usage of prayer with raised hands by the Christian faithful, but also examines the aesthetic and theological reasons for the popularity of the gesture – the parallel between the spread arms of the orans and the posture of the crucified Christ. Finally, chapter three presents a spatial-thematic analysis of the usage of the orans in the Roman Christian catacombs, using a corpus of 158 orantes. This chapter enables the reader to draw conclusions about the veracity of the academic theories presented in the previous chapters, as it compares the usage of the orans against its scholarly interpretation.

The anti-inflammatory properties of four medicinal plants were investigated. These plant extracts were subjected to screening for their possible effects as antioxidative, analgesic, and anti-inflammatory agents. In the antioxidant activity, the Plantago lancelota extracts resulted in an IC50 value of 0.4 mg/mL compared to the positive control quecertin with IC50 0.04 mg/mL Plantago lanceolata inhibited COX-2 activity with IC50 values of 0.41 mg/mL. However, the COX-1 inhibition indicated an IC50 of 68.99 mg/mL. The lipoxygenase assay indicated that Plantago lanceolata was the most active plant species with an IC50 value of 4.86 mg/mL compared to the positive control (quecertin) with an IC50<2mg/mL. The nitric oxide assay of the plant extracts indicates a dose-dependent activity of our plant extracts. Likewise the cell viability result indicated a good activity at dose 100 mg/mL. / Life and Consumer Sciences / M. Sc. (Life Sciences)

The orans, although a gesture with a long ‘pagan’ past, was easily adopted by Christians for its symbolic meanings of prayer and piety and quickly attained a number of other more nuanced meanings as it was refined and reused. By restricting the scope of this thesis to the orans in the Christian catacombs of Rome, it becomes possible to approach the figure from a multi-directional perspective, not merely concerned with what the gesture meant to the Christian, but with its literary and material pedigrees, its transition to Christian art, and its cultural significance. To this end, chapter one examines ‘pagan’ precursors of the Christian orans through an examination of coins, sculptures, inscriptions, and reliefs, as well as by looking at the two figures whose appearance most influences that of the orans – the goddess Pietas, and the Artemisia-Adorans funerary portrait type. Chapter two addresses the importance of the orans in the Christian literary community, and examines not only the actual usage of prayer with raised hands by the Christian faithful, but also examines the aesthetic and theological reasons for the popularity of the gesture – the parallel between the spread arms of the orans and the posture of the crucified Christ. Finally, chapter three presents a spatial-thematic analysis of the usage of the orans in the Roman Christian catacombs, using a corpus of 158 orantes. This chapter enables the reader to draw conclusions about the veracity of the academic theories presented in the previous chapters, as it compares the usage of the orans against its scholarly interpretation.

(1) Background: Members of the TRPC3/TRPC6/TRPC7 subfamily of canonical transient receptor potential (TRP) channels share an amino acid similarity of more than 80% and can form heteromeric channel complexes. They are directly gated by diacylglycerols in a protein kinase C-independent manner. To assess TRPC3 channel functions without concomitant protein kinase C activation, direct activators are highly desirable. (2) Methods: By screening 2000 bioactive compounds in a Ca2+ influx assay, we identified artemisinin as a TRPC3 activator. Validation and characterization of the hit was performed by applying fluorometric Ca2+ influx assays and electrophysiological patch-clamp experiments in heterologously or endogenously TRPC3-expressing cells. (3) Results: Artemisinin elicited Ca2+ entry through TRPC3 or heteromeric TRPC3:TRPC6 channels, but did not or only weakly activated TRPC6 and TRPC7. Electrophysiological recordings confirmed the reversible and repeatable TRPC3 activation by artemisinin that was inhibited by established TRPC3 channel blockers. Rectification properties and reversal potentials were similar to those observed after stimulation with a diacylglycerol mimic, indicating that artemisinin induces a similar active state as the physiological activator. In rat pheochromocytoma PC12 cells that endogenously express TRPC3, artemisinin induced a Ca2+ influx and TRPC3-like currents. (4) Conclusions: Our findings identify artemisinin as a new biologically active entity to activate recombinant or native TRPC3-bearing channel complexes in a membrane-confined fashion.

Artemisia Gentileschi and Caravaggio's Looking Glass is an ironic allusion to both the concave mirror and the biconvex lens. It was these simple objects, in colloquial terms a shaving mirror and a magnifying glass, which Artemisia Gentileschi and her father Orazio, learned from Caravaggio how to use to enhance the natural phenomenon of the camera obscura effect. Painting from a projection meant that Artemisia could achieve an extreme form of realism and detail in her work. This knowledge, which was of necessity kept hidden, spooked the Inquisition and also gave artists, who knew how to manipulate the technology, an extreme competitive edge over their rivals. This dissertation challenges the naive assumptions that have been made about Artemisia's working practices, effectively ignoring the strong causal links between art and science in Seicento Italian painting. Introducing the use of optical aids by Artemisia opens up her story to a whole new generation of scholarship. / Art History / M.A. (Art history)

Fire is an important disturbance mechanism in big sagebrush (Artemisia tridentata) communities, yet little is known about wildlife population dynamics during post-fire habitat succession. I estimated the abundance of small mammals and birds in relation to fire history in mountain big sagebrush (A.t. spp. vaseyana) communities on the Sheldon National Wildlife Refuge in the northwestern Great Basin, USA. I employed a chronosequence approach that took advantage of multiple wildfires that had occurred in similar plant communities between 7 to 20 years prior to sampling. Belding’s ground squirrel (Spermophilus beldingii) were approximately 10 times as abundant in burned areas relative to adjacent unburned habitat regardless of the number of years since a burn occurred. Deer mouse (Peromyscus maniculatus) was more abundant on more recently burned sites, but not at sites closer to full vegetation recovery. Great basin pocket mouse (Perognathus parvus), sagebrush vole (Lemmiscus curtatus), and least chipmunk (Tamius minimus) abundance did not vary as a function of fire history, but some variance was explained by habitat features such as rocky areas and the canopy characteristics of sagebrush. Bird diversity was higher in unburned habitats irrespective of the number of years of recovery out to 20 years. Nine of the 12 most widely occurring species of birds in the study have population densities influenced by fire or post-fire habitat succession to at least 13 to 20 years following a burn. Sage Sparrow (Amphispiza belli), Black-throated Sparrow (Amphispiza bilineata), and Spotted Towhee (Pipilo maculatus) occurred at relatively low densities and were nearly restricted to unburned habitats. Green-tailed Towhee (Pipilo Chlorurus), Gray Flycatcher (Empidonax wrightii), American Robin (Turdus migratorius), and Brown-headed Cowbird (Molothus ater) occurred at lower densities in burned areas than adjacent unburned areas although the relationship was not strong for the latter two species. The magnitude of the difference in density between burned and unburned sites within a landscape diminished with the number of years of vegetation recovery for Green-tailed Towhee. Brewer’s Sparrow (Spizella brewerii) occurred at lower densities relative to adjacent habitat in the most recent burn, but occurred at higher densities after 20 years of habitat succession, suggesting a positive response with a multiple decade lag period. Horned Lark (Eremophila alpestris) and Vesper Sparrow (Pooecetes gramineus) respond positively to fire, but densities were similar to unburned areas after 20 years of habitat succession. An ordination analysis captured 86% of the variation in 12 bird species with 3 orthogonal axes. My research demonstrates that strong community structure exists for birds associated with mountain big sagebrush habitats, and that fire influences community structure for multiple decades. / Graduation date: 2011 / Access restricted to the OSU Community at author's request from Dec. 22, 2010 - Dec. 22, 2011.