Landau's function for one million billions (2009)
Deléglise, Marc, Nicolas, Jean-Louis, Zimmermann, Paul
Let ${\mathfrak S}_n$ denote the symmetric group with $n$ letters, and $g(n)$ the maximal order of an element of ${\mathfrak S}_n$. If the standard factorization of $M$ into primes is...
Landau's function for one million billions (2009)
Deléglise, Marc, Nicolas, Jean-Louis, Zimmermann, Paul
Let ${\mathfrak S}_n$ denote the symmetric group with $n$ letters, and $g(n)$ the maximal order of an element of ${\mathfrak S}_n$. If the standard factorization of $M$ into primes is...
Magnetism based System for Detecting and Identifying buried Networks (2009)
Sultan Buzid, Danielle Nuzillard, Fabien Belloir, Larbi Beheim, Jean-Louis Nicolas
An innovative magnetic based system for detectingand identifying networks of buried pipes is presented. Currentlywhen a pipe is buried, a warning colored plastic is placed aboveit and its color...
On the parity of generalized partition functions III (2008)
Said, Fethi Ben, Nicolas, Jean-Louis, Zekraoui, Ahlem
Improving on some results of J.-L. Nicolas \cite {Ndeb}, the elements of the set ${\cal A}={\cal A}(1+z+z^3+z^4+z^5)$, for which the partition function $p({\cal A},n)$ (i.e. the number of partitions...
GARNIER, Matthieu, LABREUCHE, Yannick, NICOLAS, Jean-Louis
Eleven Vibrio isolates invading the hemolymph of live and moribund oysters (Crassostrea gigas) collected in the field and from a hatchery in France, were characterized by a polyphasic approach....
Landau's function for one million billions (2008)
Deleglise, Marc, Nicolas, Jean-Louis, Zimmermann, Paul
Let ${\mathfrak S}_n$ denote the symmetric group with $n$ letters, and $g(n)$ the maximal order of an element of ${\mathfrak S}_n$. If the standard factorization of $M$ into primes is...
Quelques in\'egalit\'es effectives entre des fonctions arithm\'etiques usuelles (2008)
Let us denote by $\tau(n)$ and $\si(n)$ the number and the sum of the divisors of $n$ and by $\vfi$ Euler's function. We give effective upper bounds for $\frac{n}{\vfi(n)}$ in terms of $\vfi(n)$, and...
CASTEX, Mathieu, CHIM, Liet, PHAM, Dominique, LEMAIRE, Pierrette, WABETE, Nelly, NICOLAS, Jean-Louis, ...
We studied the effects of a lactic acid bacterium, Pediococcus acidilactici (strain MA 18/5M, CNCM), as a dietary probiotic on growth performance and some nutritional and microbiological aspects of...
Quelques inégalités effectives entre des fonctions arithmétiques usuelles. (2008)
Let us denote by $\tau(n)$ and $\si(n)$ the number and the sum of the divisors of $n$ and by $\vfi$ Euler's function. We give effective upper bounds for $\frac{n}{\vfi(n)}$ in terms of $\vfi(n)$, and...
Quelques inégalités effectives entre des fonctions arithmétiques usuelles. (2008)
Let us denote by $\tau(n)$ and $\si(n)$ the number and the sum of the divisors of $n$ and by $\vfi$ Euler's function. We give effective upper bounds for $\frac{n}{\vfi(n)}$ in terms of $\vfi(n)$, and...
On the parity of generalized partition functions III. (2008)
Ben Said, Fethi, Nicolas, Jean-Louis, Zekraoui, Ahlem
Improving on some results of J.-L. Nicolas \cite {Ndeb}, the elements of the set ${\cal A}={\cal A}(1+z+z^3+z^4+z^5)$, for which the partition function $p({\cal A},n)$ (i.e. the number of partitions...
On the parity of generalized partition functions III. (2008)
Ben Said, Fethi, Nicolas, Jean-Louis, Zekraoui, Ahlem
Improving on some results of J.-L. Nicolas \cite {Ndeb}, the elements of the set ${\cal A}={\cal A}(1+z+z^3+z^4+z^5)$, for which the partition function $p({\cal A},n)$ (i.e. the number of partitions...
SAMAIN, Jean-Francois, DEGREMONT, Lionel, SOLETCHNIK, Patrick, HAURE, Joel, BEDIER, Edouard, ROPERT, Michel, ...
Summer mortality of Pacific oysters is known in several countries. However no specific pathogen has been systematically associated with this phenomenon. A complex combination of environmental and...
GARNIER, Matthieu, LABREUCHE, Yannick, GARCIA, Celine, ROBERT, Maeva, NICOLAS, Jean-Louis
A study was conducted to investigate the involvement of bacteria in oyster mortalities during summer. Moribund and apparently healthy oysters were sampled during mortality events along the French...
SAMAIN, Jean-Francois, DEGREMONT, Lionel, SOLETCHNIK, Patrick, ROPERT, Michel, BEDIER, Edouard, MAZURIE, Joseph, ...
Complex interactions between oyster, environment and pathogens were observed during the MOREST (2001-2005) project on summer mortality events of Crassostrea gigas oysters in France. The talk will...
LABREUCHE, Yannick, LAMBERT, Christophe, SOUDANT, Philippe, BOULO, Viviane, HUVET, Arnaud, NICOLAS, Jean-Louis
The strategies used by bacterial pathogens to circumvent host defense mechanisms remain largely undefined in bivalve molluscs. In this study, we investigated experimentally the interactions between...
PAILLARD, Christine, GAUSSON, Sabrina, NICOLAS, Jean-Louis, LE PENNEC, Jean Paul, HARAS, Dominique
Vibrio tapetis is the marine bacterium responsible for the brown ring disease (BRD) affecting die manila clam, Ruditapes philippinarum. Identification of V tapelis has been previously performed using...
LABREUCHE, Yannick, SOUDANT, Philippe, GONCALVES, Madeleine, LAMBERT, Christophe, NICOLAS, Jean-Louis
Vibrio aestuarianus strain 01/32 was previously shown to be pathogenic to Crassostrea gigas juveniles. To investigate virulence mechanisms of this pathogen, we studied the toxicity to oysters of its...
LONGEON, Arlette, PEDUZZI, Jean, BARTHELEMY, Michel, CORRE, Sophie, NICOLAS, Jean-Louis
A marine bacterium, X 153, was isolated from a pebble collected at St. Anne du Portzic (France). By 16S ribosomal DNA gene sequence analysis, X153 strain was identified as a Pseudoalteromonas sp....
ROBERT, Rene, CHRETIENNOT-DINET, Marie-Josèphe, KAAS, Raymond, MARTIN-JEZEQUEL, Véronique, MOAL, Jeanne, LE COZ, Jean-Rene, ...
in mollusc hatcheries. Consequently, we assessed themost commonly used species to establish their growth and size profiles, their cytomorphological, biochemical, biomolecular identification as well...
Number of solutions to $(A^2+B^2=C^2+C)$ in a binade (2003)
Muller, Jean-Michel, Nicolas, Jean-Louis, Roblot, Xavier-François
Let us denote by Q(N,[lambda]) the number of solutions of the diophantine equation $(A^2+B^2=C^2+C)$ satisfying N
Nombre de solutions dans une binade de l'equation A^2+B^2=C^2+C. (2003)
Muller, Jean-Michel, Nicolas, Jean-Louis, Roblot, Xavier-François
(eng) Let us denote by Q(N,\la) the number of solutions of the diophantine equation A^2+B^2=C^2+C satisfying N\le A\le B\le C \le \la N-\frac 12. We prove that, for \la fixed and N\to \iy, there...
Number of solutions to $(A^2+B^2=C^2+C)$ in a binade (2003)
Muller, Jean-Michel, Nicolas, Jean-Louis, Roblot, Xavier-François
Let us denote by Q(N,[lambda]) the number of solutions of the diophantine equation $(A^2+B^2=C^2+C)$ satisfying N
Number of solutions to $(A^2+B^2=C^2+C)$ in a binade (2003)
Muller, Jean-Michel, Nicolas, Jean-Louis, Roblot, Xavier-François
Let us denote by Q(N,[lambda]) the number of solutions of the diophantine equation $(A^2+B^2=C^2+C)$ satisfying N
LE ROUX, Frédérique, GAY, Melanie, LAMBERT, Christian, WAECHTER, Magali, POUBALANNE, Saravanne, CHOLLET, Bruno, ...
French mollusc production is based mainly on the Pacific cupped oyster, Crassostrea gigas. Since 1991, annual mass mortality of juveniles has been reported during summer months. These recurring...
Vibrio carchariae, a pathogen of the abalone Haliotis tuberculata (2002)
NICOLAS, Jean-Louis, BASUYAUX, Olivier, MAZURIE, Joseph, THEBAULT, Anne
Since 1997, mass mortality of the abalone Haliotis tuberculata L. has occurred in the natural environment along the French coast. The outbreak of disease started on the south coast of Brittany near...
French scallops: A new host for ostreid herpesvirus-1 (2001)
ARZUL, Isabelle, NICOLAS, Jean-Louis, DAVISON, Andrew J., RENAULT, Tristan
Sporadic high mortalities were reported among larval French scallops (Pecten maximus). Electron microscopy of moribund larvae revealed particles with the characteristics of a herpesvirus in...
Herpes-type virus infection in king scallop larvae (2001)
ARZUL, Isabelle, NICOLAS, Jean-Louis, RENAULT, Tristan
King scallop (Pecten maximus) larvae suffered massive mortality during the summer of 2000 at a hatchery located in Brittany. Samples were taken for various types of analyses.
Abalone mortality in Brittany and Normandy: characterization of the causal agent (2001)
BASUYAUX, Olivier, NICOLAS, Jean-Louis, MAZURIE, Joseph, THEBAULT, Anne
In summer 1997, massive abalone Haliotis tuberculata mortalities are monitored on the coast of Brittany, near Concarneau. They then spread out to the north of Brittany (1998) and to the Norman-Breton...
Characterisation of pathogenic bacteria, Vibrio splendidus, isolated from marine bivalves (2001)
GAY, Melanie, WAECHTER, Magali, LAMBERT, Christophe, ESCOUBAS, Jean-Michel, COCHENNEC, Nathalie, NICOLAS, Jean-Louis, ...
Nowadays, cupped oyster, Crassostrea gigas, production is the main shellfish production in France. Spats cultivated on most farms are usually collected in the wild, but hatchery spats are becoming...
Toxicity to bivalve hemocytes of pathogenic Vibrio cytoplasmic extract (2001)
LAMBERT, Christian, NICOLAS, Jean-Louis, BULTEL, Valérie
Using a chemiluminescence (CL) test, it had been previously demonstrated that Vibrio pectenicida, which is pathogenic to Pecten maximus larvae, was able to inhibit completely the CL activity of P,...
Vibriosis in bivalves : review of recent molecular, biochemical, and physiological studies (2001)
PAILLARD, Christine, NICOLAS, Jean-Louis, LE CHEVALIER, Patrick, LAMBERT, Christophe, LE BOULAY, Christine, BERTHE, Franck, ...
The emergence of new vibriosis in the European Atlantic coasts has been associated with mass mortalities of molluscs causing important economic losses. For examples, Vibrio carchariae, a bacteria...
Effects of erythromycin and oxolinic acid on Pecten maximus larval development (1998)
ROBERT, Rene, NICOLAS, Jean-Louis, CONAN, Rony
En absence d'antibiotique, les élevages larvaires de coquilles St Jacques sont sujets à de fortes mortalités. A l'écloserie expérimentale de mollusques d'Argenton (Bretagne, France), la...
Studies on the larval mortalities of the shell St Jacques Pecten maximus in eclosery (1995)
ROBERT, Rene, MINER, Philippe, NICOLAS, Jean-Louis, MAZURET, Michel, CONNAN, Jean-Paul
Larval mortalities occurring in molluscan hatcheries have often been associated with bacterial contamination. Although batches of oyster and clam larvae have been routinely reared in the hatchery of...
On practical partitions (1995)
Let $\mathcal{A} = \{a_1 = 1 < a_2 <\dots < a_k <\dots\}$ be an infinite subset of $\mathbb{N}$. A partition of $n$ with parts in $\mathcal{A}$ is a way of writing $n = a_{i_1} + a_{i_2}...
LE DEUFF, Rose-Marie, NICOLAS, Jean-Louis, RENAULT, Tristan, COCHENNEC, Nathalie
A herpes-like virus which was associated with mortalities amongst hatchery-reared larvae of Pacific oysters, Crassostrea gigas. was observed for the first time in France during the summer 1991...
Bacterial ecology in production tanks during larval scallop rearing (Pecten maximus ). (1992)
JACQ, E, MOAL, Jeanne, SAMAIN, Jean-Francois, CORRE, S, DANIEL, J, NICOLAS, Jean-Louis, ...
Larval rearings were performed with seawater either freshly pumped or after storage in a pond. Concerning bacterial populations these waters were characterized by a high diversity, little sized...
Bacteria associated with culture of Brachionus plicatilis (1984)
NICOLAS, Jean-Louis, JOUBERT, M
Bacteria associated with semi-continuous culture of Brachionus plicatilis , which is used as the first food of marine fish larvae, were counted on Zobell 2216 E medium and identified. The numbers of...
Corpet, Denis, Nicolas, Jean-Louis
Antagonistic effect of piglet microflora against Clostridium perfringens was studied in germfree mice, to isolate bacterial strains responsible for this colonization resistance. The 1:100 dilution of...
Corpet, Denis, Nicolas, Jean-Louis
Antagonistic effect of piglet microflora against Clostridium perfringens was studied in germfree mice, to isolate bacterial strains responsible for this colonization resistance. The 1:100 dilution of...