Jean Worms - Academia.edu (original) (raw)
Papers by Jean Worms
HAL (Le Centre pour la Communication Scientifique Directe), 1980
CALMAR RÉSUMÉ.-L'auteur tente de mettre en évidence les grandes lignes du cycle reproductif CYCLE... more CALMAR RÉSUMÉ.-L'auteur tente de mettre en évidence les grandes lignes du cycle reproductif CYCLE REPRODUCTIF du Calmar Loligo vulgaris (Lam.) du Golfe du Lion. L'analyse des variations mensuelles du RAPPORT GONADO-Rapport Gonado-Somatique (R.G.S.) permet de mettre en évidence l'existence chez les SOMATIQUE mâles de deux périodes de dépôt des spermatophores (janvier, février et avril-juin). Pour les femelles, l'évolution du R.G.S. montre que la ponte s'étend sur au moins 5 mois (mars à juillet). Il semble que deux cycles de reproduction, assurés par deux sous-populations différentes, se déroulent à quelques semaines d'intervalle. La relation entre le poids de l'ovaire et la longueur des glandes nidamentaires pourrait représenter un bon indice de maturité.
Pour chaque centre de débarquement la rpp,artition des captures par type de pêche est repr §senté... more Pour chaque centre de débarquement la rpp,artition des captures par type de pêche est repr §sentéefiBure'12. Les pirogues moteur-ligne assurent annuellement à Kayar, Soumbédioune. Mbour et Joal toujours plus de 85 % des èébarquements 9 le reste étant rééilisé par les pirogues à voile et à rames. A Saint-Louis, 1es'~irogues moteur-1l.gne Epinephelu8 guaza~E.~preeÎ:fJ,i8 et MycteroperpaY'übra.
Canadian Journal of Fisheries and Aquatic Sciences, 1991
Nitzschia pungens f. multiseries (clone NPARL) was grown in nonaxenic batch culture under a range... more Nitzschia pungens f. multiseries (clone NPARL) was grown in nonaxenic batch culture under a range of growth conditions. Domoic acid (DA) was not detected during exponential growth, but production promptly started at a rate of approximately 1 pg DA∙cell−1∙d−1 at the onset of the stationary phase, in this case induced by silicate limitation. Cellular DA reached a maximum of 7 pg∙cell−1; thereafter, DA production continued at the same rate, with cellular levels remaining relatively constant due to concurrent release of DA into the culture medium. DA production ceased in the absence of nitrogen during the stationary phase, but resumed when nitrate was added back to the medium. Low irradiance slowed the division rate and consequently delayed the attainment of the stationary phase, but DA production rates were comparable with the control once stationary phase was reached. Cells during the dark period of a light–dark cycle, or placed into darkness, or in the presence of the photosynthetic ...
Since the early works of Balthazar Osório, at the turn of the century, only few papers have been ... more Since the early works of Balthazar Osório, at the turn of the century, only few papers have been published on the ichthyofauna of São Tomé island. The papers dealing with these fishes were compilations of previous works or the results of a few scientific expeditions (e.g. "Galathea" and "Calypso"). In this paper, we present the results of several surveys carried out from the island over the last decade, together with an annotated revision of the known bibliography for the area. The result is an inventory of the coastal fish of São Tomé island. Our records (124 species belonging to 59 families) are based on fish captured, photographed or observed whilst diving and also on those landed by local artisanal fishermen. In this paper we report a total of 185 confirmed coastal species and 67 families. Twenty-seven of these are reported for the first time for the area, and three other unidentified species may represent new species to science. The best represented families...
Challenging Coasts, 2004
A Concerted Approach towards Managing Living Resources in a Marine Protected Area Jean Worms, Mat... more A Concerted Approach towards Managing Living Resources in a Marine Protected Area Jean Worms, Mathieu Ducrocq, and Abdelkader Ould Mohamed Saleck1 ... It also explicitly limits fishing activities by residents to those oper-ated on foot from the shore or with sailboats ...
Canadian Journal of Fisheries and Aquatic Sciences, 1993
Four clones of Nitzschia pungens f. multiseries (toxin-producing form) and two of N. pungens f. p... more Four clones of Nitzschia pungens f. multiseries (toxin-producing form) and two of N. pungens f. pungens (nontoxic) were grown in batch culture at initial nitrogen concentrations of 55, 110, 220, 440, and 880 μM in the form of either nitrate or ammonium. As expected, only N. pungens f. multiseries clones produced the neurotoxin, domoic acid (DA). Ammonium at 880 μM prevented the growth of all N. pungens clones but not of Skeletonema costatum, although division rate was reduced. At 440 μM, ammonium lowered the cell yield obtained during the stationary phase, inhibited photosynthesis, and caused a lag phase during which DA was produced (by f. multiseries). At 220 and 440 μM ammonium, in contrast with the same concentrations of nitrate, stationary phase cellular DA production was enhanced by two- to fourfold. At 110 and 55 μM nitrogen, cell yield and DA production were equivalent for nitrate and ammonium but less DA was produced relative to the higher nitrogen concentrations, possibly d...
Biochemical Systematics and Ecology, 1982
Abetract-The atlozyme polymorphism at 28 loci was examined in four Indonesian species of Rattus (... more Abetract-The atlozyme polymorphism at 28 loci was examined in four Indonesian species of Rattus (R. diardii, R. tiomanicus, R. argentivenrerand R. exulans) and in two French species (R. rattus and R. norvegicus). R. diardiiwas the most polymorphic species (H=0.089) and R. tiomanicus and R. exulans the least polymorphic (H=0.026). The six species were found to differ from one another by 2-7 diagnostic loci. The use of allozyme characters for systematic identification is discussed. Genetic relationships between the six species were established using two different methods. In both cases, the results were different from those published earlier. These results are discussed in view of the representativeness of the loci investigated.
HAL (Le Centre pour la Communication Scientifique Directe), 1980
CALMAR RÉSUMÉ.-L'auteur tente de mettre en évidence les grandes lignes du cycle reproductif CYCLE... more CALMAR RÉSUMÉ.-L'auteur tente de mettre en évidence les grandes lignes du cycle reproductif CYCLE REPRODUCTIF du Calmar Loligo vulgaris (Lam.) du Golfe du Lion. L'analyse des variations mensuelles du RAPPORT GONADO-Rapport Gonado-Somatique (R.G.S.) permet de mettre en évidence l'existence chez les SOMATIQUE mâles de deux périodes de dépôt des spermatophores (janvier, février et avril-juin). Pour les femelles, l'évolution du R.G.S. montre que la ponte s'étend sur au moins 5 mois (mars à juillet). Il semble que deux cycles de reproduction, assurés par deux sous-populations différentes, se déroulent à quelques semaines d'intervalle. La relation entre le poids de l'ovaire et la longueur des glandes nidamentaires pourrait représenter un bon indice de maturité.
Pour chaque centre de débarquement la rpp,artition des captures par type de pêche est repr §senté... more Pour chaque centre de débarquement la rpp,artition des captures par type de pêche est repr §sentéefiBure'12. Les pirogues moteur-ligne assurent annuellement à Kayar, Soumbédioune. Mbour et Joal toujours plus de 85 % des èébarquements 9 le reste étant rééilisé par les pirogues à voile et à rames. A Saint-Louis, 1es'~irogues moteur-1l.gne Epinephelu8 guaza~E.~preeÎ:fJ,i8 et MycteroperpaY'übra.
Canadian Journal of Fisheries and Aquatic Sciences, 1991
Nitzschia pungens f. multiseries (clone NPARL) was grown in nonaxenic batch culture under a range... more Nitzschia pungens f. multiseries (clone NPARL) was grown in nonaxenic batch culture under a range of growth conditions. Domoic acid (DA) was not detected during exponential growth, but production promptly started at a rate of approximately 1 pg DA∙cell−1∙d−1 at the onset of the stationary phase, in this case induced by silicate limitation. Cellular DA reached a maximum of 7 pg∙cell−1; thereafter, DA production continued at the same rate, with cellular levels remaining relatively constant due to concurrent release of DA into the culture medium. DA production ceased in the absence of nitrogen during the stationary phase, but resumed when nitrate was added back to the medium. Low irradiance slowed the division rate and consequently delayed the attainment of the stationary phase, but DA production rates were comparable with the control once stationary phase was reached. Cells during the dark period of a light–dark cycle, or placed into darkness, or in the presence of the photosynthetic ...
Since the early works of Balthazar Osório, at the turn of the century, only few papers have been ... more Since the early works of Balthazar Osório, at the turn of the century, only few papers have been published on the ichthyofauna of São Tomé island. The papers dealing with these fishes were compilations of previous works or the results of a few scientific expeditions (e.g. "Galathea" and "Calypso"). In this paper, we present the results of several surveys carried out from the island over the last decade, together with an annotated revision of the known bibliography for the area. The result is an inventory of the coastal fish of São Tomé island. Our records (124 species belonging to 59 families) are based on fish captured, photographed or observed whilst diving and also on those landed by local artisanal fishermen. In this paper we report a total of 185 confirmed coastal species and 67 families. Twenty-seven of these are reported for the first time for the area, and three other unidentified species may represent new species to science. The best represented families...
Challenging Coasts, 2004
A Concerted Approach towards Managing Living Resources in a Marine Protected Area Jean Worms, Mat... more A Concerted Approach towards Managing Living Resources in a Marine Protected Area Jean Worms, Mathieu Ducrocq, and Abdelkader Ould Mohamed Saleck1 ... It also explicitly limits fishing activities by residents to those oper-ated on foot from the shore or with sailboats ...
Canadian Journal of Fisheries and Aquatic Sciences, 1993
Four clones of Nitzschia pungens f. multiseries (toxin-producing form) and two of N. pungens f. p... more Four clones of Nitzschia pungens f. multiseries (toxin-producing form) and two of N. pungens f. pungens (nontoxic) were grown in batch culture at initial nitrogen concentrations of 55, 110, 220, 440, and 880 μM in the form of either nitrate or ammonium. As expected, only N. pungens f. multiseries clones produced the neurotoxin, domoic acid (DA). Ammonium at 880 μM prevented the growth of all N. pungens clones but not of Skeletonema costatum, although division rate was reduced. At 440 μM, ammonium lowered the cell yield obtained during the stationary phase, inhibited photosynthesis, and caused a lag phase during which DA was produced (by f. multiseries). At 220 and 440 μM ammonium, in contrast with the same concentrations of nitrate, stationary phase cellular DA production was enhanced by two- to fourfold. At 110 and 55 μM nitrogen, cell yield and DA production were equivalent for nitrate and ammonium but less DA was produced relative to the higher nitrogen concentrations, possibly d...
Biochemical Systematics and Ecology, 1982
Abetract-The atlozyme polymorphism at 28 loci was examined in four Indonesian species of Rattus (... more Abetract-The atlozyme polymorphism at 28 loci was examined in four Indonesian species of Rattus (R. diardii, R. tiomanicus, R. argentivenrerand R. exulans) and in two French species (R. rattus and R. norvegicus). R. diardiiwas the most polymorphic species (H=0.089) and R. tiomanicus and R. exulans the least polymorphic (H=0.026). The six species were found to differ from one another by 2-7 diagnostic loci. The use of allozyme characters for systematic identification is discussed. Genetic relationships between the six species were established using two different methods. In both cases, the results were different from those published earlier. These results are discussed in view of the representativeness of the loci investigated.