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Search Results: 1 - 10 of 3339 matches for " Annabelle Fernandez "
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Two Coregulated Efflux Transporters Modulate Intracellular Heme and Protoporphyrin IX Availability in Streptococcus agalactiae
Annabelle Fernandez ,Delphine Lechardeur,Aurélie Derré-Bobillot,Elisabeth Couvé,Philippe Gaudu,Alexandra Gruss
PLOS Pathogens , 2010, DOI: 10.1371/journal.ppat.1000860
Abstract: Streptococcus agalactiae is a major neonatal pathogen whose infectious route involves septicemia. This pathogen does not synthesize heme, but scavenges it from blood to activate a respiration metabolism, which increases bacterial cell density and is required for full virulence. Factors that regulate heme pools in S. agalactiae are unknown. Here we report that one main strategy of heme and protoporphyrin IX (PPIX) homeostasis in S. agalactiae is based on a regulated system of efflux using two newly characterized operons, gbs1753 gbs1752 (called pefA pefB), and gbs1402 gbs1401 gbs1400 (called pefR pefC pefD), where pef stands for ‘porphyrin-regulated efflux’. In vitro and in vivo data show that PefR, a MarR-superfamily protein, is a repressor of both operons. Heme or PPIX both alleviate PefR-mediated repression. We show that bacteria inactivated for both Pef efflux systems display accrued sensitivity to these porphyrins, and give evidence that they accumulate intracellularly. The ΔpefR mutant, in which both pef operons are up-regulated, is defective for heme-dependent respiration, and attenuated for virulence. We conclude that this new efflux regulon controls intracellular heme and PPIX availability in S. agalactiae, and is needed for its capacity to undergo respiration metabolism, and to infect the host.
Structural Studies on ι-Carrageenan Derived Oligosaccharides and Its Application  [PDF]
Annabelle V. Briones, Toshinori Sato
Advances in Chemical Engineering and Science (ACES) , 2014, DOI: 10.4236/aces.2014.41003
Abstract:

Mild hydrochloric acid hydrolysis of i-carrageenan from Eucheuma spinosum yielded two oligosaccharides of sulfated tetrasaccharide structure. These were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR) and Electrospray Ionization Mass Spectrometry (ESIMS). Both oligosaccharides have structure of b-D-galactopyranose(Galp)4S-(14)-α-D-AnGalp2S-(13)-b-D-galactopyranose Galp)4S-(14)-α-D-AnGalp2S-(13). Application of the resulting oligosaccharides on protein delivery system in terms of encapsulation efficiency was performed.

Impacts locaux de la mondialisation
Annabelle Boissier
SociologieS , 2012,
Abstract: Cet article s’attache à analyser la réorganisation du marché de l’art tunisien suite à la tenue d’expositions réalisées par des commissaires d’expositions indépendants au début des années deux mille. Afin de conserver ou d’acquérir du leadership sur le marché local, les galeristes ont mis en uvre quatre types d’actions : le renouvellement des artistes, la formation de la clientèle par l’exercice de l’expertise, l’internationalisation et la diversification des activités de la galerie. L’analyse de ces actions montre que la modification des procès de production générée par la mondialisation du monde de l’art contemporain relève d’un mouvement d’internationalisation dont l’objectif est le renversement des pouvoirs nationaux dans le but de créer un monde de l’art contemporain local. Cette étude montre néanmoins que l’engagement dans ces nouveaux procès de production comporte des risques freinant l’inscription des galeristes et artistes tunisiens au sein du marché international. Globalization’s local impacts. The difficult engagement of leader galleries in TunisiaThis article aims to analyse the reorganisation of the Tunisian art market at the beginning of the years 2000s. It is during this period that exhibitions are held and organized by independent curators. In order to maintain or obtain a certain level of leadership on the local art market, gallery owners implemented four types of actions: the renewal of artists, the formation of costumers by means of experts’ mediation, internationalisation and the diversification of the galleries’ activities. The analysis of these actions shows that the transformation of the processes of production generated by the globalisation of contemporary art is in fact a dynamic leading towards internationalisation. Furthermore, the objective of this dynamic is to overthrow national powers in order to create a contemporary local art world. Nevertheless, the Tunisian case shows that the commitment inside these new production processes carries risks that restrict the international recognition of gallery owners and artists. Impactos locales de la mundialización. El delicado compromiso del liderazgo de las galerías tunecinasEste artículo se ata a analizar la reorganización del mercado del arte tunecino en respuesta a la postura de exposiciones realizadas por comisarios independientes de exposiciones al principio de los a os dos mil. Con el fin de conservar o de adquirir del liderazgo sobre el mercado local, las galerías pusieron en ejecución cuatro tipos de acciones: la renovación de los artistas, la formación de la clientela por
Portraits, publics and politics: Gisele Wulfsohn's photographs of HIV/AIDS, 1987-2007
Annabelle Wienand
Kronos (Bellville) , 2012,
Abstract: Contemporary South African documentary photography is often framed in relation to the history of apartheid and the resistance movement. A number of well-known South African photographers came of age in the 1980s and many of them went on to receive critical acclaim locally and abroad. In comparison, Gisele Wulfsohn (19572011) has remained relatively unknown despite her involvement in the Afrapix collective and her important contribution to HIV/AIDS awareness and education. In focusing on Wulfsohn's extended engagement with the issue of HIV/AIDS in South Africa, this article aims to highlight the distinctive nature of Wulfsohn's visualisation of the epidemic. Wulfsohn photographed the epidemic long before there was major public interest in the issue and continued to do so for twenty years. Her approach is unique in a number of ways, most notably in her use of portraiture and her documentation of subjects from varied racial, cultural and socio-economic backgrounds in South Africa. The essay tracks the development of the different projects Wulfsohn embarked on and situates her photographs of HIV/AIDS in relation to her politically informed work of the late 1980s, her personal projects and the relationships she developed with non-governmental organisations.
The water connection: Irrigation, water grabbing and politics in southern Morocco
Annabelle Houdret
Water Alternatives , 2012,
Abstract: Water and land grabbing is often an indication of growing control by an elite group over natural resources for agricultural production, marginalising their previous users. It may drive and exacerbate social, economic and political disparities and so increase the potential for conflict. In Southern Morocco’s Souss valley, the overuse of water resources is causing aquifer levels to sink and agricultural land to be abandoned. At the same time, irrigated agriculture is still expanding, often permitting the lucrative growing of citrus fruits. This export-oriented agriculture mostly benefits the economic elite, increasing their political influence. Small farmers, on the other hand, face growing threats to their livelihoods. A public-private partnership (PPP) project reallocating water through a 90 km pipeline from a mountain region to plantations in the valley has been implemented to enhance water supply and save dying citrus plantations. However, it is accentuating disparities between farmers. We trace the dynamics of marginalisation linked to this PPP and use emerging water conflicts as a lens to analyse the appropriation of water resources and the underlying political and economic relationships and strategies. On the basis of the case study, we show that water conflicts are as much struggles over political influence as over the resource itself and, consequently, that the related phenomenon of 'water grabbing' is not only driven by economic interests but also determined by a political agenda of regime stability and economic control. However, we also point to the opportunities presented by recent social and political changes in Morocco, including the influence of the 'Arab Spring', and argue that such processes as increasing transparency, decentralisation and the empowerment of local civil society support the re-appropriation of water, livelihoods and power. We conclude by examining the limits of this PPP model, which has been internationally praised by financial institutions, and calling for a careful evaluation of its ecological and social impacts before such experience is replicated elsewhere.
Tuning to the Language of Relationship in Student Teaching
Annabelle Slocum
Analytic Teaching and Philosophical Praxis , 1995,
Abstract: As a teacher educator of pre-service students, part of my responsibility is to supervise students during their practice teaching rounds. During conversations with associate teachers,’ many questions have been raised about their role in relation to the Practicum. These questions in turn prompted me to consider, how might we understand the nature of the relationship between an associate teacher and a student teacher? As I pondered onmy understanding of this relationship, I wondered about it in terms of what is written in faculty of education handbooks and educational literature. Was there more? How might associate teachers1experiences be listened to and written about differently? Associate teachers speak in terms of personal uncertainty, professional dutyand a feeling of being taken-for-granted (Slocum, 1989). They talk about discovering conflicts in their positions,their concerns and tensions and the pleasure and excitement of experiencing collegiality with the studentteacher (Slocum, 1989). Is this pointed to as part of the associate teachers role and responsibility in practicumhandbooks? In other words, what remains silent and hidden and taken for granted about this relationship? In what way may we enter into this relationship so that the invisible becomes visible?
Pensar e viver para além das categorias do real e do irreal: Merleau-Ponty e o imaginário operante
Annabelle Dufourcq
DoisPontos , 2012,
Abstract: The dimension of violence and the radically destabilizing implications of Merleau-Ponty’s thought are sometimes, too often, overlooked. The merleau-pontian flesh is not first and foremost peaceful, it is an explosive and open being, within which self-coincidence, rest and truth in a classical sense are impossible. This article intends to demonstrate that MP makes the classical distinction between the real and the unreal collapse, entailing a deep reorganization of the fields of knowledge and ethics and, somehow, a fusion between them. If the very being is unfinished and open to interpretations, then there is no truth to be known, we only have “images” of the world and, correlatively, images are more revealing of the on-going meaning in which the world consists than any so-called absolute knowledge. Moreover, to accept the creative dimension of interpretation as requested by the world itself permits to realize that one cannot understand the world without acting and that to act is to set up a balance between, on the one hand, the patient attention paid to the nascent meaning in situations and, on the other hand, a bold shaping of the given elements of meaning that are always “in-themselves” scattered and ambiguous.
On Rational Points of Varieties over Local Fields having a Model with Tame Quotient Singularities
Annabelle Hartmann
Mathematics , 2012, DOI: 10.1090/S0002-9947-2015-06291-6
Abstract: We study rational points on a smooth variety X over a complete local field K with algebraically closed residue field, and models of X with tame quotient singularities. If a model of X is the quotient of a Galois action on a weak N\'eron model of the base change of X to a tame Galois extension of K, then we construct a canonical weak N\'eron model of X with a map to this model, and examine its special fiber. As an application we get examples of singular models of X such that X has K-rational points specializing to a singular point of this model. Moreover we obtain formulas for the motivic Serre invariant and the rational volume, and the existence of K-rational points on certain K-varieties with potential good reduction.
The quotient map on the equivariant Grothendieck ring of varieties
Annabelle Hartmann
Mathematics , 2014,
Abstract: For a scheme S with a good action of a finite abelian group G having enough roots of unity we show that the quotient map on the G-equivariant Grothendieck ring of varieties over S is well defined with image in the Grothendieck ring of varieties over S/G in the tame case, and in the modified Grothendieck ring in the wild case. To prove this we use a result on the class of the quotient of a vector space by a quasi-linear action in the Grothendieck ring of varieties due to Esnault and Viehweg, which we also generalize to the case of wild actions. As an application we deduce that the quotient of the motivic nearby fiber is a well defined invariant.
Equivariant motivic integration on formal schemes and the motivic zeta function
Annabelle Hartmann
Mathematics , 2015,
Abstract: For a formal scheme over a complete discrete valuation ring with a good action of a finite group, we define equivariant motivic integration, and we prove a change of variable formula for that.To do so, we construct and examine an induced group action on the Greenberg scheme of such a formal scheme. Using this equivariant motivic integration, we define an equivariant volume Poincar\'e series, from which we deduce Denef and Loeser's motivic zeta function including the action of the profinite group of roots of unity.
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