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This paper describes critical assembly process qualifications, acceptance criteria, and worker training of ITER Central Solenoid Assembly. Coaxial joint assembly was qualified and trained to achieve resistance below 4.1 nOhm. The electrical insulation process was qualified to 30 kV and 15 kV under Paschen conditions. Shear pin drilling and installation within specified tolerance was achieved. Modules were lifted and positioned within 2 mm. The lessons learned, and subsequent work execution onsite within the IO facility assembly hall are also presented.

La polyarthrite rhumatoïde est un rhumatisme inflammatoire fréquent pouvant s’associer à des manifestations dermatologiques telles que des nodules rhumatoïdes, une vasculite rhumatoïde ou des manifestations granulomateuses. Ces dernières sont rares et peuvent se présenter sous diverses formes cliniques.

•Klebsiellaspp. meningitis should be considered in patients presenting with meningitis following neurosurgical procedures.•Post-neurosurgery isolates had significantly higher carriage rates of ESBL or acquired AmpC.•The in-hospital case fatality rate was 23.6%, close to that observed in patients with pneumococcal meningitis.

Cardiovascular diseases represent the leading cause of death worldwide. In a previous survey, we have shown that the management of patients with atherosclerosis by general practitioners depends on the locations of the disease. The aim of this survey was to assess general practice residents’ (GPR) knowledge on three clinical presentations which are ischemic stroke, coronary artery disease (CAD), and peripheral artery disease (PAD).

Les inhibiteurs de PD-1 et de PDL-1 utilisés de manière croissante dans le traitement des cancers peuvent être responsables d’effets secondaires inflammatoires cutanés immuno-médiés. Des connectivites cutanées immuno-induites ont été rarement décrites. Nous rapportons le deuxième cas de lupus subaigu (LSA) induit par le durvalumab.

Hybrid PET/CT and PET/MRI are increasingly important technologies in the evaluation of malignancy and require cooperation between radiologists and specialists in molecular imaging. The aim of our study was to probe the mindsets of radiological and nuclear medicine professionals in regard to current hybrid imaging practice and to assess relevant training aspirations and perceived shortfalls, particularly amongst young professionals. In this context, we initiated an international survey on “Hybrid Imaging Training”. An online survey was prepared on-line and launched on October-2, 2016. It was composed of 17 multiple-choice and open questions regarding the professional background, a perspective on hybrid imaging training efforts and lessons to be learned from disparate craft groups. The survey ran for 2 weeks. We report total responses per category and individual free-text responses. In total, 248 responses were collected with a mean age of all responders of (41 ± 11) y. Overall, 36% were within the target age range of (20–35) y. Across all responders, the majority (72%) commented on there being too few hybrid imaging experts in their country, whereas only 1% said that there were too many. Three quarters of the responders were in favour of a curriculum allowing sub-specialisation in hybrid imaging. With respect to reporting of hybrid imaging, confidence increased with age. The average rating across all responders on the level of cooperation among the two specialties suggested a low overall level of satisfaction. However, the survey feedback indicated the local (on-site) cooperation being somewhat better than the perceived cooperation between the relevant associations on a European level. We consider these results to represent an appropriate cross-section of professional opinions of imaging experts across different demographic and hierarchical levels. Collectively they provide evidence supporting a need to address current shortfalls in developing hybrid imaging expertise through national educational plans, and, thus, contribute to helping improve patient care.

L'intégration du dépistage du cancer du sein dans les soins cliniques quotidiens conduit à un diagnostic précoce et diminue sa mortalité. De nombreuses femmes, cependant sont réticentes et ne se font pas dépister.

We report experimental results obtained on cleaved (-201) surface of Rb0.3MoO3 using low temperature scanning tunnelling microscopy under ultra-high vacuum (UHV-LT-STM). Molecular resolution has been obtained at 63 K, 78 K and 300 K. At low temperatures, both the molecular lattice and CDW superlattice were observed simultaneously in topographical constant current images.

La graisse n’est pas un simple tissu de comblement. En plus de son rôle de réserve énergique et de son implication dans des mécanismes hormonaux, elle possède dans certaines zones du corps des propriétés mécaniques sous-estimées. Ainsi, au niveau du genou, la graisse antérieure, qui présente une anatomie plus complexe qu’il n’y paraît, doit résister à d’importantes forces de cisaillement et de compression. Lorsque ces contraintes mécaniques dépassent les limites physiologiques, on observera des lésions spécifiques peu connues. La graisse superficielle est ainsi un site de dissection « aiguë » appelé décollement de Morel-Lavallée, ou subit un clivage plus complexe, moins franc en cas de cisaillement chronique, aboutissant à la formation d’une « néo-bursite » ou « hygroma ». La graisse antérieure profonde se décompose en 3 « matelas » principaux intracapsulaires mais extrasynoviaux : le corps adipeux infrapatellaire (CAiP) ou graisse de Hoffa, le matelas suprapatellaire et enfin le matelas préfémoral ou supratrochléen. Le CAiP de Hoffa joue un rôle mécanique important en servant « d’amortisseur » et de « guide » au tendon patellaire et même à la patella lors des mouvements de flexion-extension. Lorsque les contraintes répétées sur cette structure anatomique deviennent trop importantes, elle réagit dans un premier temps par une réaction inflammatoire et une augmentation de volume, puis peut secondairement se « métaplasier » en tissu fibreux, voire en cartilage ou en os. De façon plus rare, les deux autres matelas graisseux profonds (suprapatellaire et supratrochléen) peuvent également, suite à des contraintes répétées, subir le même type de remaniement inflammatoire et évoluer vers une métaplasie en un tissu plus « dur », avec comme corollaire une douleur antérieure et une limitation fonctionnelle.

L’articulation du genou est une des régions anatomiques les plus explorées en imagerie. La découverte d’une anomalie osseuse, en rapport ou non avec la symptomatologie ayant motivé l’examen, est extrêmement fréquente. L’objectif de ce travail est de présenter une revue iconographique des pathologies osseuses les plus fréquentes du genou. Rappelons d’emblée que l’IRM doit toujours être interprétée en ayant la connaissance de la clinique, de la biologie et des clichés standard.

Les états initiaux des surfaces de matériaux métalliques et les premières étapes d'oxydation peuvent conditionner leur comportement en oxydation à long terme. Ainsi, l'objet de cette étude est de caractériser les couches formées sur différents échantillons : alliages base nickel et chrome pur, en milieu aqueux à haute température, pour des durées courtes d'oxydation. La technique d'analyse principale est la spectroscopie de photoélectrons XPS. Elle permet, d'une part, l'étude qualitative des espèces présentes en surface (environnement chimique, états d'oxydation) et d'autre part, une approche semi-quantitative. Nous avons travaillé en mode " profil ", par une succession d'abrasions ioniques entrecoupées d'analyses en vue d'obtenir une répartition des espèces au sein de la couche d'oxyde. En complément, des mesures réalisées par analyse nucléaire (NRA) ont permis d'étalonner la vitesse de décapage ionique et de déterminer ainsi l'épaisseur de la couche d'oxyde. Les données obtenues permettent de proposer un modèle de répartition des différentes espèces dans la couche d'oxyde en fonction du type d'alliage et de la durée d'oxydation.

L’exploration d’une « tuméfaction ou masse du poignet ou de la main » est un exercice fréquent dans notre activité quotidienne. Dans la plupart des cas, le couple radiologie standard et échographie suffit au diagnostic, les kystes du poignet étant de loin la pathologie la plus fréquente. Le recours aux autres modalités d’imagerie, et en particulier à l’IRM, est indispensable pour l’exploration des tumeurs, bien que les tumeurs malignes de la main soient exceptionnelles. Certaines tumeurs bénignes ont des caractéristiques pathognomoniques en imagerie, leur connaissance permet d’améliorer leur prise en charge.

Les infiltrations sous guidage échographique connaissent ces dernières années un essor important. La main est un site idéal pour ce type de geste en raison de son anatomie complexe et du caractère superficiel des cibles potentielles. À condition de respecter quelques principes de bases (asepsie stricte, patient et médecin bien installés, suivi de la pointe de l’aiguille en temps réel, repérage consciencieux des nerfs et des vaisseaux), il sera possible à l’opérateur entraîné d’infiltrer à peu près « tout et n’importe quoi ». Après vous avoir livré quelques astuces utiles (comme le « gel pad » ou l’angulation des aiguilles), nous décrirons les gestes les plus fréquemment réalisés aux doigts et aux poignets : infiltration des doigts à ressaut, des rhizarthroses, des ténosynovites de De Quervain, des canaux carpiens, etc. Enfin, nous aborderons les modifications que ce type de procédures peuvent induire dans les relations avec vos correspondants : « l’échographiste » qui pratique ces gestes n’est plus seulement un « imageur » mais devient un « thérapeute » et empiète sur des domaines de compétences appartenant traditionnellement à la rhumatologie, à la rééducation fonctionnelle ou même à la chirurgie de la main.

La pathologie des extenseurs des doigts longs bénéficie essentiellement des avancées technologiques de l’échographie, dont la résolution spatiale facilite considérablement le diagnostic. La connaissance précise de l’anatomie tendineuse des doigts longs et des signes cliniques est indispensable pour établir un diagnostic et permettre la prise en charge correcte des patients.

Le système fléchisseur des doigts, constitué par les tendons fléchisseurs et les poulies digitales, est l’élément anatomique clé de la fonction de préhension. Les sportifs et les travailleurs manuels sont particulièrement exposés aux traumatismes fermés de l’appareil fléchisseur : rupture des poulies, rupture distale du tendon fléchisseur profond (« jersey finger »), plus rarement rupture du fléchisseur superficiel ou des muscles lombricaux. Les traumatismes ouverts sont plus polymorphes et leur bilan en imagerie est complexe : plusieurs sections tendineuses possibles, localisations non standardisées, lésions nerveuses et vasculaires associées, fibrose… L’échographie est le prolongement idéal de l’examen clinique, permettant le plus souvent à un opérateur entraîné de réaliser un diagnostic précis et précoce, essentiel à une prise en charge initiale adaptée.

Les blépharites ont des origines mal définies et multiples. L’objectif de cette étude a été d’étudier la flore bactérienne présente chez les patients atteints de blépharite par rapport à des sujets sains dans la perspective d’apprécier la place des étiologies bactériennes dans les blépharites.

Les avancées technologiques effectuées ces dernières années en identification bactérienne grâce à la biologie moléculaire et la spectrométrie de masse ou Matrix Assisted Laser Desorption Ionisation-Time of Flight (MALDI-TOF) ont permis de mettre en évidence de nouvelles bactéries impliquées dans les infections du tractus urinaire. Le but de cette revue est de faire connaître aux cliniciens ces différents germes afin qu’ils pensent à les rechercher spécifiquement chez une population ciblée et d’aider les biologistes à les suspecter et les identifier.

The goal of this paper is to describe a full approach of a decentralized control strategy applied on an industrial multivariable application: a turboprop engine. A first step consists in the linearization of the turboprop engine model around different operating points. After noting strong interactions, decoupling methods are tested in order to reduce the coupling effects. A decentralized strategy is then set up, and PID controllers are further designed. The control laws are finally implemented in order to command a non-linear model of a turboprop engine.

To evaluate the distribution of white matter (WM) disease in frontotemporal lobar degeneration (FTLD) and Alzheimer disease (AD) and to evaluate the relative usefulness of WM and gray matter (GM) for distinguishing these conditions in vivo.

AbstractMolten Salt Reactors based on the thorium cycle were studied in the 1950 to 1960s to lead to the Molten Salt Breeder Reactor concept, which was finally discontinued prior to any industrial development. In the past few years, this concept has once again been studied in order to generalize it and seek configurations ensuring a high intrinsic safety level, an initial inventory compatible with intensive deployment on a worldwide scale, and a not-too-demanding salt chemical reprocessing scheme.The Thorium Molten Salt Reactor (TMSR) thus defined is studied in the Th-233U cycle in various configurations obtained by modulating the amount of graphite in core to obtain a thermal, an epithermal, or a fast spectrum. In particular, configurations of a fast spectrum TMSR have been identified with outstanding safety characteristics and minimal fuel-reprocessing requirements.

AbstractThe MUSE-4 program is a series of zero-power experiments carried out at the Commissariat à l’Energie Atomique Cadarache MASURCA nuclear facility from 2001 to 2004 to study the neutronics of accelerator-driven systems (ADSs). The program has investigated the coupling of a multiplying medium to neutron sources of 2.6 or 14 MeV provided by an accelerator (GENEPI) via D(d,n)3He or T(d,n)4He nuclear fusion reactions, respectively. The fuel was UO2-PuO2, the simulated coolant was sodium or lead, and the multiplication factor keffranged from 1 to 0.95. The aim of the experiment was to develop new measurement techniques specific to ADSs and to test the performances of neutronic calculations codes for such systems.The interpretation of the MUSE-4 experiment has shown that the physical parameters of the system are globally well reproduced by calculations performed with the ERANOS code system, which proves good agreement with both the measurements and the reference Monte Carlo calculations; this concerns the critical mass, the delayed neutron fraction, the fission rate shapes, and the spectral indices. This is a particularly remarkable issue for ERANOS and its associated libraries, which had never been tested for such situations.Concerning the nuclear data, JEF-based cross sections provide a better agreement on critical mass than other libraries. A sensitivity of several measured parameters to the elastic and inelastic cross section of lead have been demonstrated, and possible biases on these cross sections have been indicated.We have shown that several methods based on deterministic or stochastic calculations allow us to relate the experimental neutron population decay after a source pulse with the reactivity of the system; these reactivity determination techniques are in good agreement with standard reactivity measurement techniques.

La chirurgie mini-invasive et la récupération améliorée après chirurgie (RAAC) sont deux axes d’optimisation de la cystectomie totale (CT). L’objectif de cette étude est d’évaluer l’impact de la mise en place d’un protocole de RAAC chez les patients opérés d’une CT pour cancer en termes de complications postopératoires et de résultats oncologiques.

De plus en plus souvent, les autorités de santé et les agences d’évaluation françaises sont conduites à délivrer des AMM (Autorisation de Mise sur le Marché), à rendre des avis sur l’admission au remboursement de médicaments ou à élaborer des recommandations pour la pratique clinique à partir de résultats d’études étrangères. Les résultats de ces études sont plus ou moins difficiles à transposer à la pratique française. Ces difficultés génèrent une incertitude de degré variable sur l’effet à attendre d’un médicament. Une perte d’effet plus ou moins importante est quelquefois même prévisible. Quelques unes des difficultés de transposition sont discutées dans cet article et des propositions d’actions sont formulées pour permettre, à terme, de prédire de la façon la plus précise possible les effets à attendre d’un médicament en population française et de pouvoir vérifier cette prédiction à distance de son admission au remboursement.

More and more frequently, the health authorities and the French assessment agencies are led to issue Marketing Authorizations (MAs), give opinions on the eligibility for reimbursement of drugs or to draft recommendations for clinical practice based on the results of foreign studies. The results of these studies are more or less difficult to transpose to French practice. These difficulties generate varying degrees of uncertainty concerning the effect to be expected of a drug. A more or less extensive loss of effect is sometimes even predictable. Some of the difficulties in transposition are discussed in this article and proposals for action are made in order to allow one, in the long term, to predict in the most precise manner possible the effects to be expected from a drug in the French population and be able to verify this prediction at an interval from its eligibility for reimbursement.

The growing worldwide demand for energy must be controlled. However, even in the event of voluntary policies to dampen energy demand, it is hard to imagine that the demand could be less than twice as much as today's by 2050. We feel it is necessary to satisfy this demand. It is obvious also that greenhouse gas emissions must be reduced in order to limit the severe consequences that they entail. An energy shortage could develop if new sources of large-scale energy production are not established. A significant contribution of nuclear power to such energy production by 2050 rests on a well-coordinated and optimised deployment scheme (Loiseaux et al., 2004; The Future of Nuclear Power, 2003). This requires, as early as today, a reflection on the present status of nuclear power, on its extrapolation into the future and, thus, on the means that should be put to work and the transition possibilities.

AbstractThe MUSE program (multiplication with an external source) is in progress at the MASURCA critical facility at the Cadarache Research Center of the Commissariat à l’Energie Atomique in France. The program is dedicated to the physics studies of accelerator-driven systems in support of transmutation studies of minor actinides and long-lived fission products. It began in 1995 with the coupling of a Cf source in MASURCA and was followed by a commercial (d,T) source. In 2001, a specially constructed (d,D)/(d,T) neutron generator (GENEPI) was placed in MASURCA and the MUSE-4 program commenced.We describe the first phases of the MUSE-4 program, with data presented that were obtained up to about the summer of 2002. We present some results from the “reference” configuration, which can operate at critical. We present traverses of measured fission reaction rates, with comparison to calculations. Also in the reference configuration, we performed activation foil measurements and present these results compared to calculations.Because a major objective of the MUSE program is to test and qualify methods of subcritical reactivity measurement, we have devoted a major portion of our studies to this area. We have used classical methods (rod drop, source multiplication) to attempt to measure the subcritical level. In these early phases we studied core configurations of around keff= 0.995. Deeper subcriticality (keff= 0.96) was achieved by inserting a safety rod.In addition to the methods mentioned above, we have devoted a lot of effort to pulse neutron source, fluctuation (Rossi-α and Feynman-α), and transfer function methods (e.g., cross-power spectral density). We present our preliminary results of all the methods, with some discussion regarding cross comparison.

Wakes, and their interaction behind two parallel cylinders lying in a plane perpendicular to the flow, have been investigated experimentally in the sub-critical Reynolds number regime. The experiments were performed in a water channel using laser Doppler velocimetry. The gap between the two cylinders was less than the cylinder diameter, a geometry referred to as strong interaction configuration. In this case the blockage is strong and a gap-jet appears between the cylinders. Two flow regimes of the near wake region have been identified: one below a critical Reynolds number Re c ?]1000;1700[, where the gap jet is stably deflected to one side and the double near-wake becomes asymmetric; the other, above Re c, where the gap-jet deflection is unstable and a random flopping phenomenon takes place. When Re< Re c, two different Strouhal numbers are identified, related to the Kármán vortex shedding behind each cylinder. When Re> Re c, a third frequency appears in the near wake, related to the development of Kelvin-Helmholtz vortices in the separated shear layer of the cylinders [Prasad A, Williamson CHK (1997) J Fluid Mech 333:375]. The observed flopping behavior is attributed to the birth of these Kelvin-Helmholtz instabilities and their intermittent nature. Further downstream, beyond about five cylinder diameters, the random flopping flow phenomena disappear while a slightly asymmetric single wake persists. It is characterized by a Strouhal number St=0.13, a value that one would normally measure behind a single cylinder of twice its diameter.

A polypropylene (PP) modified by ethylene–propylene rubber (EPR) was treated in vacuo by α particles (with an energy of 400 keV) with fluences that varied from 10¹¹ to 10¹⁶ He⁺ cm⁻². Samples were investigated with attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, contact-angle measurements, differential scanning calorimetry, swelling, nanoindentation, and friction techniques. After treatment, new chemical groups (carbonyl and vinyl bonds) appeared at the PP/EPR surface. These chemical modifications led to changes in the surface free energy of PP/EPR. Irradiation also modified the PP/EPR structure because crosslinking occurred after treatment for fluences above or equal to 5 × 10¹⁴ He⁺ cm⁻². Moreover, the PP melting temperature and enthalpy were greatly decreased for fluences above or equal to 10¹⁴ He⁺ cm⁻². The surface mechanical properties were also changed after treatment. Indeed, the friction coefficient decreased, whereas the hardness and Young's modulus drastically increased, after irradiation at higher fluences. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1183–1191, 2003

Abstract. I factors are non-LTR retrotransposons of Drosophila melanogaster that transpose at high frequency in the germline of females resulting from appropriate crosses, allowing in vivo studies of the retrotransposition process. Reverse transcription of a full-length RNA intermediate is thought to occur at the site of integration, using a 3′ hydroxyl group generated by endonucleolytic cleavage of the genomic DNA to prime synthesis of the first cDNA strand. This target-primed reverse transcription (TPRT) process is mediated by endonuclease and reverse transcriptase activities encoded by the element. We have designed a molecularly tagged, endonuclease-defective I element that can be mobilised with high efficiency by constructs that express the product of the I factor ORF2 in trans. This indicates that the endonuclease activity required for retrotransposition of the I factor can be provided in trans. Using this system, we show that the endonuclease domain of the R1Bm retrotransposon from Bombyx mori cannot functionally replace that of the I factor.

This paper presents an unsupervised, all-words, word sense disambiguation system for English. The system associates a word with its meaning in a given context using an electronic dictionary as a tagged corpora in order to extract semantic disambiguation rules. The methodology attempts to avoid the data acquisition bottleneck observed in word sense disambiguation techniques. Semantic rules are used as input of a semantic application program encoding a linguistic strategy in order to select the best rule to apply. The semantic rule extraction process as well as the application program is described. The methodology is developed in a client/server architecture, which enables the treatment of large corpora. The evaluation of the system is then detailed and some possible extensions and perspectives are finally proposed.

We present the sequence of a contiguous 2.63 Mb of DNA extending from the tip of the X chromosome of Drosophila melanogaster. Within this sequence, we predict 277 protein coding genes, of which 94 had been sequenced already in the course of studying the biology of their gene products, and examples of 12 different transposable elements. We show that an interval between bands 3A2 and 3C2, believed in the 1970s to show a correlation between the number of bands on the polytene chromosomes and the 20 genes identified by conventional genetics, is predicted to contain 45 genes from its DNA sequence. We have determined the insertion sites of P-elements from 111 mutant lines, about half of which are in a position likely to affect the expression of novel predicted genes, thus representing a resource for subsequent functional genomic analysis. We compare the European Drosophila Genome Project sequence with the corresponding part of the independently assembled and annotated Joint Sequence determined through "shotgun" sequencing. Discounting differences in the distribution of known transposable elements between the strains sequenced in the two projects, we detected three major sequence differences, two of which are probably explained by errors in assembly; the origin of the third major difference is unclear. In addition there are eight sequence gaps within the Joint Sequence. At least six of these eight gaps are likely to be sites of transposable elements; the other two are complex. Of the 275 genes in common to both projects, 60% are identical within 1% of their predicted amino-acid sequence and 31% show minor differences such as in choice of translation initiation or termination codons; the remaining 9% show major differences in interpretation.

Recent experimental results concerning heavy systems (Pb+Au, Pb+Ag, Pb+Al, Gd+C, Gd+U, Xe+Sn, …) obtained at GANIL with the INDRA and NAUTILUS 4πarrays will be presented. The study of reaction mechanisms has shown the dominant binary and highly dissipative character of the process. The two heavy and excited fragments produced after the first stage of the interaction can decay into various decay modes from evaporation to multifragmentation including fission. However, deviations from this simple picture have been found by analyzing angular and velocity distributions of light charged particles, and fragments. Indeed, there is a certain amount of matter in excess emitted between the two primary sources suggesting either the existence of a mid-rapidity source similar to the one observed in the relativistic regime (participants) or a strong deformation induced by the dynamics of the collision (neck instability). This last possibility has been suggested by analyzing in detail the angular distributions of the fragments. More precisely, we observe an isotropic component which is compatible with the prediction of statistical models and a second one corresponding to breakup aligned with the recoil direction of the projectile like source which should be compared with the predictions of dynamical calculations based on microscopic transport models.

Abstract:: Proton and deuteron correlation functions have been investigated with both impact parameter and emission source selections. The correlations of the system 129Xe+NatSn at 50 AMeV have been measured with the 4π INDRA which provides a complete kinematical description of each event. The emission time scale analyzed with a quantum model reveals the time sequence of the light particles emitted by the projectile-like fragment. The short and constant emission time of the proton, independent of the impact parameter, can be attributed to a preequilibrium process.

L’apraxie d’ouverture des yeux (APO) est définie comme l’impossibilité d’ouvrir volontairement les yeux, en l’absence de troubles oculomoteurs ou de blépharospasme. La physiopathologie est toujours discutée. Nous rapportons le cas d’un patient, ayant un antécédent de maladie de Parkinson, présentant une APO dans le contexte d’un accident vasculaire cérébral aigu. Notre cas clinique permet de discuter le rôle déclencheur respectif, d’une part, de la lésion neurovasculaire et de sa localisation, et d’autre part, de la maladie neurodégénérative, ainsi que d’une éventuelle potentialisation de ces deux affections.

Abstract:: Cross sections for stripping and dissociation of deuterons interacting with Be targets in the 100–2300 MeV energy range have been measured. Comparisons with model calculations suggest a dominant contribution of the stripping process. It is also shown that the deuteron break-up cross section exhibits the same energy dependence as the nucleon-nucleon cross section.

Band shift assays were used to study proteins from the fission yeast that bind double-stranded telomeric repeat sequences. We also examine general DNA binding properties of the telobox domain, which characterizes telomere-binding proteins from a range of species. We demonstrate that Taz1p has a high affinity for the fission yeast telomeric repeat, consistent with genetic results implicating this protein in telomere maintenance. A second Schizosaccharomyces pombe telobox protein, Teb1p, is shown to bind with high affinity to the vertebrate repeat and with low affinity to the fission yeast telomeric DNA. When tested on G-rich single-stranded telomeric DNA, all these proteins bind with very low affinity, much like the human telomere-binding protein TRF1. Recombinant proteins containing just the telobox domains reproduce the specificity of binding demonstrated for the corresponding full-length proteins, indicating that the telobox domain is indeed responsible for specific DNA recognition. The presence of possible Teb1p-binding sites upstream of many genes suggests a role for this protein as a general transcription factor. Finally, band shift experiments with whole cell extracts from wild-type and taz1 (-)strains suggest that in addition to Taz1p, S.pombe has another major telomere-binding activity.

The reduction of U3O8 by hydrogen has been studied by thermogravimetry in the range 510–600°C and 1–40 kPa hydrogen partial pressure. The kinetic curves have been interpreted by a new model involving steps of nucleation and growth in which the rate limiting step of growth is located at the external interface. This allowed us to determine the variations in the areic nucleation frequency and the areic reactivity of growth as a function of hydrogen pressure and temperature. Mechanisms have been proposed which account for the variations in the areic nucleation frequency and reactivity of growth as a function of the partial pressure of hydrogen and the temperature of reduction. The influence of the hydration of UO3 prior to its reduction by hydrogen on the kinetics could also be explained by the same model. It was found to lower the areic nucleation frequency without changing the areic growth reactivity.

We have previously mapped scaffold-attached regions (SARs) on an 800-kilobase DNA walk from the Drosophila X chromosome. We have also previously shown that the strength of binding, i.e., the ability of SARs to bind to all nuclear scaffolds or only to a fraction of them varied from one SAR to another one. In the present study, 71 of the 85 subfragments that bind scaffolds and 38 fragments that do not bind scaffolds were tested for their ability to promote autonomous replicating sequence (ARS) activity in Saccharomyces cerevisiae. Sixteen SAR-containing fragments from the chromosome walk were also examined for association to yeast nuclear scaffolds in vitro. All identified ARSs (a total of 27) were present on SAR-containing fragments, except two, which were adjacent to SARs. There is thus a correlation between ARS and SAR activities, and this correlation defines a SAR subclass. Moreover, the presence of an ARS on a DNA fragment appeared to be highly correlated with the strength of binding. The binding activity was highly conserved from Drosophila melanogaster to yeast. These data suggest that Drosophila DNA sequences responsible for binding to components of the nuclear scaffold from either D. melanogaster or yeast may be involved in the process of heterologous extrachromosomal replication in yeasts.

Low energyp+ andp- production cross sections have been measured in16O at 65 MeV/u and84Kr at 60 MeV/u induced reactions on7Li,12C,27Al,108Ag and197Au. The results are compared with a previous measurement obtained with16O at 93 MeV/u. Large deviations are observed between light and heavy ion data. At variance with16O, the ratiosp-/p+ are independent of the target in the Krypton case. A change in the regime of the projectile-target mass scaling of cross-sections is observed with the heaviest projectile.

New techniques for mapping mammalian DNA replication origins are needed. We have modified the existing nascent-strand size analysis technique (L. Vassilev and E.M. Johnson, Nucleic Acids Res. 17:7693-7705, 1989) to provide an independent means of studying replication initiation sites. We call the new method nascent-strand abundance analysis. We confirmed the validity of this method with replicating simian virus 40 DNA as a model. We then applied nascent-strand abundance and nascent-strand size analyses to mapping of initiation sites in human (HeLa) ribosomal DNA (rDNA), a region previously examined exclusively by two-dimensional gel electrophoresis methods (R.D. Little, T.H.K. Platt, and C.L. Schildkraut, Mol. Cell. Biol. 13:6600-6613, 1993). Our results partly confirm those obtained by two-dimensional gel electrophoresis techniques. Both studies suggest that replication initiates at relatively high frequency a few kilobase pairs upstream of the transcribed region and that many additional low-frequency initiation sites are distributed through most of the remainder of the ribosomal DNA repeat unit.

A case of postpartum renal failure and malignant hypertension in a 24-year-old woman is reported. The condition occurred three weeks after caesarian section following a normotensive pregnancy. Treatment with a converting enzyme inhibitor, captopril, for one year normalized the blood pressure, with concurrent reduction of plasma angiotension II concentration and markedly improved glomerular filtration rate. It is suggested that activation of the renin-angiotensin system may cause the hypertension and impairment of renal function in postpartum renal failure, and that use of drugs blocking the renin system may be of particular clinical value in this situation.

Two DNA fragments displaying ARS activity on plasmids in the yeast Yarrowia lipolytica have previously been cloned and shown to harbor centromeric sequences (P. Fournier, A. Abbas, M. Chasles, B. Kudla, D. M. Ogrydziak, D. Yaver, J.-W. Xuan, A. Peito, A.-M. Ribet, C. Feynerol, F. He, and C. Gaillardin, Proc. Natl. Acad. Sci. USA 90:4912-4916, 1993; and P. Fournier, L. Guyaneux, M. Chasles, and C. Gaillardin, Yeast 7:25-36, 1991). We have used the integration properties of centromeric sequences to show that all Y. lipolytica ARS elements so far isolated are composed of both a replication origin and a centromere. The sequence and the distance between the origin and centromere do not seem to play a critical role, and many origins can function in association with one given centromere. A centromeric plasmid can therefore be used to clone putative chromosomal origins coming from several genomic locations, which confer the replicative property on the plasmid. The DNA sequences responsible for initiation in plasmids are short (several hundred base pairs) stretches which map close to or at replication initiation sites in the chromosome. Their chromosomal deletion abolishes initiation, but changing their chromosomal environment does not.

Summary The insecticide lindane does not influence bacterial growth but can inhibit eucaryotic microorganism multiplication at levels depending upon the species. For short treatments the inhibition is reversible. It takes place during mitosis in plant cells which does not seem to be the case in animal cells.Acetabularia morphogenesis is slowed or arrested with the insecticide which is probably linked to a slow down of the cytoplasmic streaming. DNA synthesis is still occurring in treated cells. The possible targets, plasma membrane or contractile structures, are discussed.