L'Union Europeenne et la Zeon du Pacifique

L'Union européenne est présente, sous des formes diverses, dans la région Pacifique. Au-delà du cadre de sa politique commerciale extérieure, elle a des accords d'association avec un certain nombre de territoires insulaires. Ainsi, parmi les 20 pays et territoires d'outre-mer (PTOM) énumérés dans l'annexe I de la décision 91/482/CEE du Conseil du 25 juillet 1991, relative à l'association des pays et territoires d'outre-mer à la Communauté économique européenne , cinq sont situés dans la zone Pacifique : quatre territoires français, Polynésie française, Nouvelle Calédonie et ses dépendances, îles Wallis et Futuna, terres australes et antarctiques françaises et une colonie britannique, Pitcairn. Huit pays ACP ("Afrique, Caraïbes, Pacifique") appartiennent à la même zone géographique: Fidji, Kiribati, Papouasie Nouvelle Guinée, îles Salomon, Samoa occidentales, Tonga, Tuvalu, Vanuatu. Ces pays ont donc noué des relations d'association avec l'Union européenne dans le cadre des conventions de Lomé

Do glycerolipids display lateral heterogeneity in the thylakoid membrane?

The lateral heterogeneity of lipids in the thylakoid membrane has been questioned for over 20 yrs. It is generally believed that glycerolipids are asymmetrically distributed within the plane of the membrane. In the present investigation, we isolated several thylakoid membrane domains by using sonication followed by separation in an aqueous dextran-polyethylene glycol two-phase system. This technique, which avoids detergent treatments, allowed us to obtain stroma and grana lamellae vesicles as well as grana central core and grana margin vesicles from thylakoids. The relative distribution of the four lipid classes, i.e., monogalactosyldiacylglycerol, digalactosyldiacylglycerol, sulfoquinovosyldiacylglycerol, and phosphatidylglycerol, was found to be statistically identical in all four thylakoid fractions and in whole thylakoids. Similarly, the relative amount of fatty acids in each individual lipid and the eight main phosphatidylglycerol molecular species was identical in all thylakoid membrane fractions tested as well as in the intact thylakoid membrane. Based on presently available procedures for obtaining thylakoid subfractions that are unable to discriminate microdomains within the membrane, it is concluded that glycerolipids are evenly distributed within the plane of the thylakoid membrane. These data are discussed in terms of "bulk” and "specific” lipid

Cyclodextrins: A potential tool for studying the role of glycerolipids in photosynthetic membranes

A novel cyclodextrin derivative, i.e., permethylated-α-cyclodextrin (PM-α-CD), was used for removing glycerolipids from spinach thylakoid membranes and investigating their role in photosynthetic activities. A three-step selective removal of each lipid class was observed in treated membranes. Up to a concentration of 4 mM, PM-α-CD (in the presence of 75 μg chlorophyll a+b/mL), PM-α-CD displayed a marked selectivity for anionic lipids [sulfoquinovosyldiacylglycerol (SQDG) and phosphatidylglycerol (PG)] in comparison with galactolipids. At this concentration, half of PG and SQDG were removed. Within this range of concentration, the volume response of treated thylakoids to variation of osmolarity, an indirect mean of verifying the structural integrity of the membrane, was not altered. Similarly, neither photosystem II (PSII) nor photosystem I (PSI) activity was affected. In contrast, the low-temperature fluorescence ratio F695/F740 drastically diminished from 1.45 to about 0.7, essentially due to the decrease of PSII fluorescence. The results derived from the fast fluorescence rise expressed in the form of a spider suggest that the fraction of inactivated (non-QA reducing) reaction centers (RC) increases while the active (QA reducing) RC remained intact. Raising the concentration of PM-α-CD from 4 to 7 mM resulted in a progressive but greater diminution of the galactolipid level than that of SQDG and PG. Within this concentration range, the integrity of the membrane was not altered, nor was either PSII or PSI activity, whereas the F695/F740 ratio decreased to about 0.45 as well as the fraction of inactivated RC. At concentrations above 7 mM of PM-α-CD, the integrity of the membrane was impaired, resulting in a decrease of both electron transport activities. At all concentrations, PM-α-CD did not show any selectivity toward either the acyl chains of the lipid molecules or the molecular species of PG. The results are discussed in terms of the role of glycerolipids in thylakoid membrane function and the relationship of the chemical structure of PM-α-CD and its lipid removal capacit

Umbilical Cord Blood Banking

[À l'origine dans / Was originally part of : CRDP - Droit, biotechnologie et rapport au milieu]The umbilical cord, previously considered as waste and discarded at birth, is a source of haematopoietic stem cells. Current therapeutic uses of umbilical cord blood stem cells and the promise of these cells for the treatment of degenerative diseases in the future have led to the establishment of cord blood banks in many parts of the world. Although umbilical cord blood banking raises many ethical and legal issues, this article focuses on the controversy created by the coexistence of public and private cord blood banks in many countries. Policy statements adopted by professional associations and advisory groups indicate that, based on the current state of medical evidence, childbearing women with no current or potential familial need of stem cell transplantation should be encouraged to donate cord blood to public banks

LE CANON LITTERAIRE OCCIDENTAL DANS LE PACIFIQUE FRANCOPHONE

Sylvie André, Université de la Polynésie Française (UPF

LE CANON LITTERAIRE OCCIDENTAL DANS LE PACIFIQUE FRANCOPHONE

Sylvie André, Université de la Polynésie Française (UPF

Uma leitura comparada das artes selvagens: Lévi-Strauss e Breton nos Estados Unidos

Lors de la deuxième guerre mondiale, Claude Lévi-Strauss et André Breton se sont retrouvés dans le navire qui les amène à New York. Ils vivent alors dans le même cercle d’intellectuels expatriés. On lira Tristes Tropiques (1955) comme le résultat d’échanges avec Breton et les écrivains, où la forme et l’apport littéraires sont omniprésents pour évaluer l’originalité et les apports du texte anthropologique lui-même. Dans cette œuvre Lévi-Strauss s’interroge plus particulièrement sur toutes les formes de récits de « l’Ailleurs » et sur les conditions de la connaissancescientifique des sociétés humaines. Dès les premiers articles intégrés par la suite dans l’Anthropologie structurale (1958) il développe des définitions intéressantes de l’activité créatrice à propos des mythes. En miroir, on peut apprécier l’importance de la rencontre de l’ethnologue pour André Breton et la vision de l’art qu’il développe à cette époque : un art dont la dimension sociale est de plus en plus affirmée. Au contact de l’ethnologie et de Claude Lévi-Strauss, André Breton conçoit et développe son appel à la nécessité de création d’un mythe contemporain qu’il appellera ‘les grands transparents’. En 1955 il lui soumet un questionnaire pour la préparation de l’Art magique. Ce que nous connaissons de la correspondance du poète et de l’ethnologue, permet d’apprécier la suite de leurs discussions et la façon dont ils nourrissent leurs conceptions personnelles.Durante a segunda guerra mundial, Claude Lévi-Strauss e André Breton se encontraram no navio que os conduzia a Nova York. Viviam a mesma experiência de intelectuais expatriados. Tristes Trópicos (1955) pode ser lido como o resultado de trocas com Breton e outros escritores, em que a forma e a contribuição literárias são onipresentes afin de avaliar a originalidade e as contribuições do próprio texto antropológico. Nesta obra, Lévi-Strauss se interroga especificamente sobre todas as formas de relato do “Além” e sobre as condições do conhecimento científico das sociedades humanas. A partir de seus primeiros artigos até Antropologia estrutural (1958), Lévi-Strauss desenvolve algumas definições interessantes da atividade criadora em relação aos mitos. Especularmente, pode-se notar a importância do encontro do etnólogo com André Breton e a visão da arte que ele estava desenvolvendo: um tipo de arte cuja dimensão social estava afirmada com maior intensidade. Estando em contato com a etnologia e Claude Lévi-Strauss, André Breton concebe e desenvolve sua necessidade de criação de um mito contemporâneo que denominará ‘os grandes transparentes’. Em 1955 o etnólogo propõe um questionário para a preparação de L’Art magique. Por meio da correspondência entre o poeta e o etnólogo, podemos apreciar as discussões e o que alimentou suas concepções pessoais

Accounting for spatial autocorrelation improves the estimation of climate, physical environment and vegetation’s effects on boreal forest’s burn rates

Context: Wildfires play a crucial role in maintaining ecological and societal functions of North American boreal forests. Because of their contagious way of spreading, using statistical methods dealing with spatial autocorrelation has become a major challenge in fire studies analyzing how environmental factors affect their spatial variability. Objectives: We aimed to demonstrate the performance of a spatially explicit method accounting for spatial autocorrelation in burn rates modelling, and to use this method to determine the relative contribution of climate, physical environment and vegetation to the spatial variability of burn rates between 1972 and 2015. Methods: Using a 482,000 km2 territory located in the coniferous boreal forest of eastern Canada, we built and compared burn rates models with and without accounting for spatial autocorrelation. The relative contribution of climate, physical environment and vegetation to the burn rates variability was identified with variance partitioning. Results: Accounting for spatial autocorrelation improved the models’ performance by a factor of 1.5. Our method allowed the unadulterated extraction of the contribution of climate, physical environment and vegetation to the spatial variability of burn rates. This contribution was similar for the three groups of factors. The spatial autocorrelation extent was linked to the fire size distribution. Conclusions: Accounting for spatial autocorrelation can highly improve models and avoids biased results and misinterpretation. Considering climate, physical environment and vegetation altogether is essential, especially when attempting to predict future area burned. In addition to the direct effect of climate, changes in vegetation could have important impacts on future burn rates