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Cilia are ubiquitous and highly conserved extensions that endow the cell with motility and sensory functions. They were present in the first eukaryotes and conserved throughout evolution (Carvalho-Santos et al., 2011). Paramecium has around 4,000 motile cilia on its surface arranged in longitudinal rows, beating in waves to ensure movement and feeding. As with cilia in other model organisms, direction and speed of Paramecium ciliary beating is under bioelectric control of ciliary ion channels. In multiciliated cells of metazoans as well as paramecia, the cilia become physically entrained to beat in metachronal waves. This ciliated organism, Paramecium, is an attractive model for multidisciplinary approaches to dissect the location, structure and function of ciliary ion channels and other proteins involved in ciliary beating. Swimming behavior also can be a read-out of the role of cilia in sensory signal transduction. A cilium emanates from a BB, structurally equivalent to the centriole anchored at the cell surface, and elongates an axoneme composed of microtubule doublets enclosed in a ciliary membrane contiguous with the plasma membrane. The connection between the BB and the axoneme constitutes the transition zone, which serves as a diffusion barrier between the intracellular space and the cilium, defining the ciliary compartment. Human pathologies affecting cilia structure or function, are called ciliopathies, which are caused by gene mutations. For that reason, the molecular mechanisms and structural aspects of cilia assembly and function are actively studied using a variety of model systems, ranging from unicellular organisms to metazoa. In this review, we will highlight the use of Paramecium as a model to decipher ciliary beating mechanisms as well as high resolution insights into BB structure and anchoring. We will show that study of cilia in Paramecium promotes our understanding of cilia formation and function. In addition, we demonstrate that Paramecium could be a useful tool to validate candidate genes for ciliopathies.

The arbitration case concerning the delimitation of the maritime boundary between Bangladesh and India provides an original contribution to international law. The delimitation made by the Arbitral Tribunal is a classic application of the method of equidistance and relevant circumstances. However, the Tribunal analyses finely the value to be attributed to ancient maps and confronts itself to the thorny issue of the effect to be attributed to climate change when drawing a border. It contributes greatly to the future of the law of delimitation anchoring strongly the delimitation exercise in a well-defined time frame : the moment of the judgment. This case is also the second maritime delimitation case dealing with the delimitation of the outer continental shelf. By using the principles established by the International Tribunal for the Law of the Sea in the Bangladesh/ Myanmar case and by affirming its jurisdiction vis-à-vis the extended continental shelf, the jurisprudence of this Arbitral Tribunal strengthens the implementation of the legal regime continental shelf and advocates a harmonious joint work of the Commission on the Limits of the Continental Shelf and of International Courts and Tribunals., L’affaire d’arbitrage relatif à la délimitation de la frontière maritime entre le Bangladesh et l’Inde offre une contribution originale au droit international. La délimitation réalisée par le Tribunal arbitral suit une application classique de la méthode de l’équidistance et des circonstances pertinentes. Le Tribunal analyse cependant très finement la valeur à attribuer aux cartes anciennes et se confronte à la question épineuse de l’effet à attribuer au changement climatique lors du tracé d’une frontière. Il contribue ainsi grandement à l’avenir du droit de la délimitation en ancrant très fortement l’exercice de délimitation dans un espace-temps bien défini : le moment présent du jugement. Cette affaire est par ailleurs la deuxième affaire de délimitation maritime traitant de la délimitation du plateau continental étendu. En reprenant les principes dégagés par le Tribunal international du droit de la mer en l’affaire Bangladesh/ Myanmar et en affirmant sa compétence vis-à-vis du plateau continental étendu, la jurisprudence de ce Tribunal arbitral renforce la mise en oeuvre du régime juridique du plateau continental et prône une articulation harmonieuse du travail de la Commission des Limites du Plateau Continental et des cours et tribunaux internationaux., Tassin Virginie J. M. La contribution au droit international de l’affaire de délimitation maritime Bangladesh/Inde dans la baie du Bengale. In: Annuaire français de droit international, volume 60, 2014. pp. 109-132.

The continuous technological innovations which took place after the 1958 Geneva Conventions has led to an important development of exploration and exploitation activities on the seabed through an increased number of platforms at sea. The 1982 United Nations Convention on the Law of the Sea does not give a definition of a platform. Likewise, the other conventions which contain provisions applicable to platforms do not provide a definition of this them. It is possible, nevertheless, to define the legal régime applicable to platforms, taking into account the legal status of the different areas where they are located (continental shelf and exclusive economic zone, high seas and international seabed area) as well as of the seabed and the superjacent waters. As a result, the régime of platforms may be characterized as a complex system where the rights of the coastal States need to coexist with the rights of other States to use the areas concerned. Certain questions require a more detailed examination in light of the practical issues which have arisen in international practice. This concerns the navigation of platforms, their installation in disputed maritime areas, the safety of platforms and the protection of the marine environment (prevention and reparation) vis-à-vis damage which may occur from their activities, as well as the removal of disused platforms., Le progrès continu des techniques depuis les Conventions de Genève de 1958 a favorisé l’expansion considérable de l’exploration et de l’exploitation du fond des mers à partir de plates-formes installées en surface, qui se sont multipliées et diversifiées. La Convention des Nations Unies de 1982 ne comporte pas de définition précise, et les conventions particulières qui leur consacrent certaines de leurs dispositions ne s’accordent pas sur une définition uniforme. Il est cependant possible de systématiser le régime qui leur est applicable, en tenant compte de la diversité juridique des espaces dans lesquels elles sont implantées (plateau continental et zone économique exclusive, haute mer et Zone internationale des fonds marins) et du statut respectif des fonds marins et des eaux surjacentes. Il en résulte un régime complexe, dans lequel les droits de l’État côtier coexistent avec le droit qu’ont les États d’utiliser les espaces concernés. Certaines matières spécifiques font l’objet d’un examen plus détaillé, en raison des problèmes concrets que suscitent l’installation et l’utilisation des plates-formes en mer. Il s’agit des questions relatives à la navigation des plates-formes, à leur installation dans des zones où le titre territorial est contesté, à la sécurité des plates-formes et à la protection du milieu marin (prévention et réparation des dommages) contre la pollution qui peut résulter de leurs activités, ainsi qu’à l’enlèvement des plates-formes désaffectées., Gautier Philippe, Tassin Virginie J. M. Les plates-formes en mer et le droit international. In: Annuaire français de droit international, volume 59, 2013. pp. 185-220.

In a fundamental test of quantum mechanics, we have observed 228~000 quantum jumps of a single trapped and laser cooled $^{88}$Sr$^+$ ion. This represents a statistical increase of two orders of magnitude over previous similar analyses of quantum jumps. Compared to other searches for non-randomness in quantum mechanical processes, using quantum jumps simplifies the interpretation of data by eliminated multi-particle effects and providing near-unit detection efficiency of transitions. We measure the fractional reduction in the entropy of information to be $< 6.5~10^{-4}$ when the value of any interval between quantum jumps is known. We also find that the number of runs of successively increasing or decreasing interval times agrees with the theoretically expected values. Furthermore, we analyze 238~000 quantum jumps from two simultaneously confined ions and find that the number of apparently coincidental transitions is as expected. Finally, we observe 8400 spontaneous decays of two simultaneously trapped ions and find that the number of apparently coincidental decays from the metastable state agrees with the expected value. We find no evidence for short- or long-term correlations in the intervals of the quantum jumps or in the decay of the quantum states, in agreement with quantum theory., 4 pages, 5 figures. To appear in PRA. New version replaces much of the previous analysis with a more simple measurement of the reduction of entropy of information. Also includes smaller changes to text and figures to improve clarity

The Saccharomyces cerevisiae mating pheromone precursor, prepro-alpha-factor, can be translocated across yeast endoplasmic reticulum membranes post-translationally in an in vitro system. This characteristic makes prepro-alpha-factor potentially useful as a probe in the biochemical dissection of the mechanism of this basic cellular process. Efforts have been limited by the inability to isolate sufficient quantities of such secretory protein precursors in a translocation-competent form. We report here the one-step purification of chemical amounts of translocation-competent prepro-alpha-factor using nickel ion affinity chromatography on nitrilotriacetate resin. An oligonucleotide encoding 6 histidine residues was inserted into a genomic clone encoding prepro-alpha-factor 5' of the naturally occurring translational stop codon by site-directed mutagenesis. The construct was expressed at high levels in a SecY- strain of Escherichia coli. The produced preprotein was solubilized in 6 M guanidine hydrochloride and bound to nitrilotriacetate resin. Prepro-alpha-factor was recovered at a purity in excess of 95% by elution with 0.25 M imidazole, 8 M urea, which competitively displaced the histidine affinity tag from the nickel column. The chemical amounts of prepro-alpha-factor obtained in this way were determined to be competent for translocation across yeast microsomal membranes and for subsequent modifications such as signal sequence cleavage and N-linked glycosylation.

The electrochemical reduction of dinitronaphthalene to produce diaminonaphthalene has been optimized. The synthesis of diaminonaphthalene by the electrolysis of a suspension of dinitronaphthalene in sulphuric acid with a titanium salt gives a yield and purity similar to the synthesis by catalytic hydrogenation. Technical and economical comparisons of the two processes show that for large capacities (several hundred tons per year), reduction by catalytic hydrogenation is more feasible. However, for smaller quantities (several tons per year) the flexibility of exploitation by electrolysis has economic advantages.

Microtubule organization and nucleation were studied during in vitro human myogenesis by immunocytology that used monoclonal and polyclonal antitubulin antibodies and a rabbit nonimmune serum that reacts with human centrosomes. In myoblasts, we observed a classical microtubule network centered on juxtanuclear centrosomes. Myotubes possessed numerous microtubules organized in parallel without any apparent nucleation centers. Centrosomes in these cells were not associated one to each nucleus but were often clustered in the vicinity of nuclei groups. They were significantly smaller than those of the mononucleated cells. The periphery of each nucleus in myotubes was labeled with the serum that labels centrosomes suggesting a profound reorganization of microtubule-nucleating material. Regrowth experiments after Nocodazole treatment established that microtubules were growing from the periphery of the nuclei. The redistribution of nucleating material was shown to take place early after myoblast fusion. Such a phenomenon appears to be specific to myogenic differentiation in that artificially induced polykaryons behaved differently: the centrosomes aggregated to form only one or a few giant nucleating centers and the nuclei did not participate directly in the nucleation of microtubules. The significance of these results is discussed in relation to the possible role of the centrosome in establishing cell polarity.