Academic literature on the topic 'Amphibiens – Effets du sel'
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Journal articles on the topic "Amphibiens – Effets du sel"
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LORRAIN-SOLIGON, Léa, Frédéric ROBIN, Pierre ROUSSEAU, Marko JANKOVIC, and François BRISCHOUX. "Des petites différences pour de grands bénéfices : réponses sites-spécifiques des communautés d’amphibiens à la submersion marine sur la côte Atlantique française." Sciences Eaux & Territoires, no. 41 (September 23, 2022): xx. http://dx.doi.org/10.20870/revue-set.2022.41.7124.
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La côte Atlantique française a été frappée par la tempête Xynthia en février 2010, ce qui a probablement affecté les espèces côtières. Des relevés de salinité associés à des relevés d’espèces (amphibiens), présentés dans l’étude de Lorrain-Soligon et al. (2021), ont été réalisés sur deux réserves côtières en Charente-Maritime (les réserves naturelles nationales de Moëze-Oléron et du marais d’Yves), afin d’étudier les effets de la submersion et de l’augmentation de la salinité résultante. Ces relevés ont permis de mettre en évidence les caractéristiques topographiques des sites pouvant limiter l’impact des submersions marines sur la faune côtière.
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Agbohessi, Prudencio, and Ibrahim Imorou Toko. "Effets toxiques des herbicides à base du glyphosate sur les poissons et autres animaux aquatiques : approche bibliographique." International Journal of Biological and Chemical Sciences 15, no. 6 (February 23, 2022): 2685–700. http://dx.doi.org/10.4314/ijbcs.v15i6.33.
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Le glyphosate est un herbicide total foliaire systémique dont le principe actif est rarement utilisé seul mais le plus souvent mélangé à des formulants. Afin de faire la lumière sur ses effets toxicologiques sur les écosystèmes aquatiques, un travail de synthèse documentaire nous a permis d’établir sa toxicité sur les poissons, les invertébrés aquatiques et les amphibiens. Ainsi les CL50-96 h (Concentrations létales médianes sur 96 h) sur les poissons varient de 0,03 mg/L (Ictalurus punctatus) à 975 mg/L (Phalloceros caudimaculatus). Les effets chroniques recensés sur les poissons sont, entre autres, l’altération de la mémoire, la réduction de la mobilité, les dommages sur les paramètres hématologiques et plusieurs lésions histopathologiques sur les branchies, le tube digestif, le foie et le rein. Chez les invertébrés, les CL50 varient de 3-100 mg m.a/L (Daphnia magna) à 147 mg m.a/L (Ceriodaphnia dubia) avec, entre autres, comme effets chroniques les perturbations de la reproduction et du développement, les perturbations des fonctions cardiaques et des paramètres du stress oxydatif. Les CL50 varient chez les amphibiens de 78 mg m.a/L (Crinia insignifera) à 138,9 mg m.a/L (Rana clamitans). Au total, les effets toxiques sont induits par de fortes concentrations du polluant et ainsi le glyphosate est considéré par la majorité des auteurs, peu toxique à la faune aquatique.
English title: Toxic effects of glyphosate-based herbicides on fish and other aquatic animals: bibliographic approach
Glyphosate is a total foliar systemic herbicide, whose active ingredient is rarely used alone but more often mixed with formulants. In order to shed light on its toxicological effects on aquatic ecosystems, documentary synthesis has enabled us to establish its toxicity on fish, aquatic invertebrates and amphibians.Thus, LC50-96 h (Median Lethal Concentrations over 96 h) on fish vary from 0.03 mg / L (Ictalurus punctatus) to 975 mg / L (Phalloceros caudimaculatus). Recurrent chronic effects in fish include impaired memory, reduced mobility, damage to haematological parameters and several histopathological lesions on the gills, digestive tract, liver and kidney. In invertebrates, LC50s vary from 3-100 mg ai / L (Daphnia magna) to 147 mg ai / L (Ceriodaphnia dubia) with, among other chronic effects, disturbances of reproduction and development, disturbances of cardiac functions and parameters of oxidative stress. LC50s vary in amphibians from 78 mg a.i / L (Crinia insignifera) to 138.9 mg a.i / L (Rana clamitans). In conclusion, the toxic effects are induced by high concentrations of the pollutant, consequently, glyphosate is considered by the majority of authors to be of low toxicity to aquatic fauna.
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Villard, Marc-André, Marc J. Mazerolle, and Samuel Haché. "L’impact des routes, au-delà des collisions : le cas des oiseaux forestiers et des amphibiens." Le Naturaliste canadien 136, no. 2 (May 11, 2012): 61–65. http://dx.doi.org/10.7202/1009108ar.
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Bien que plus difficiles à quantifier, les effets indirects des routes sur la faune devraient être considérés au même titre que la mortalité routière, car certaines espèces évitent les abords des routes au moins durant une partie de l’année, ce qui peut mener à une fragmentation plus ou moins permanente de leurs populations. D’autre part, on observe chez plusieurs espèces un effet de bordure suivant lequel les abords des routes constituent un habitat de qualité marginale en raison du bruit, des substances et particules projetées par le passage des véhicules, des substances utilisées pour l’entretien routier (p. ex. sels de déglaçage) ou d’autres facteurs. Les oiseaux forestiers étudiés s’avèrent sensibles à la présence de routes à circulation intense, probablement en raison de la pollution sonore, alors qu’une espèce étudiée s’est avérée relativement tolérante à la construction d’une route de gravier. Quant aux amphibiens, les juvéniles en dispersion de 3 des 5 espèces étudiées semblaient éviter la traversée de routes pavées. Les gestionnaires de l’environnement devraient planifier l’aménagement des réseaux routiers dans la perspective du paysage afin d’éviter de dégrader ou de fragmenter les habitats critiques et de créer des barrières pour les mouvements saisonniers des espèces sensibles.
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Wang, M. N., and C. Chen. "Dynamic Modeling and Optimized Energy Distribution of a Novel Amphibian Legged Robot." Key Engineering Materials 392-394 (October 2008): 223–28. http://dx.doi.org/10.4028/www.scientific.net/kem.392-394.223.
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The development of a novel amphibian walking robot prototype is proposed according to the need of duty under bad circumstance. It can be used as the carrier of the reconnaissance equipment, the weapon system and the communication system, and complete many kinds of missions in the place near the sea and tideland which a man can not complete. Some new dynamics questions is introduced because of multi-leg structure features and functionality of the amphibious. The integrated approach of series parallel is proposed to solve the characteristic that swing and supporting phase are appeared respectively during walking. Hydrodynamic effect is also considered in our dynamics equation. At last, the least distribution model of driving moment and driving energy of robot are set up in this paper. These conclusions have very important effects to the control of robots.
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Manus, Jean-Marie. "Hypertension artérielle : le sel a-t-il ou non des effets biologiques ?" Revue Française des Laboratoires 2001, no. 335 (September 2001): 14. http://dx.doi.org/10.1016/s0338-9898(01)80214-6.
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Rivas, Gilson A., Oscar M. Lasso-Alcalá, Douglas Rodríguez-Olarte, Mayke De Freitas, John C. Murphy, Cristian Pizzigalli, John C. Weber, Laurent de Verteuil, and Michael J. Jowers. "Biogeographical patterns of amphibians and reptiles in the northernmost coastal montane complex of South America." PLOS ONE 16, no. 3 (March 4, 2021): e0246829. http://dx.doi.org/10.1371/journal.pone.0246829.
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We examine, for the first time, biogeographic patterns in a series of tropical montane coastal systems in northern South America. We use amphibians and reptiles, which constitute the most critical communities based upon the prevalence of endemic taxa, to assess the region’s biodiversity. The montane coastal system spans an east-west distance of 925 km. It includes peaks ranging from 549 m to 2765 m above sea level and encompasses the montane complexes of northern Venezuela (including Isla de Margarita), an outlier at Santa Marta (Colombia), and ranges on the islands Trinidad and Tobago. The area supports 14 family level amphibian clades and 23 family level reptile clades. Fieldwork, museum specimen surveys, and a literature review suggest that biodiversity decreases at higher elevations. Here we examine the biogeographic patterns in the region to assess the role of the montane systems as possible refugia. We also look at the possible island and sky island effects using data from altitudes >200 m. At lower elevations, we tabulated 294 species, comprising 112 amphibians and 182 reptiles. About 45% of these taxa are endemic or exclusive to different sub-regions. At mid-elevation montane cloud forests, we find a much-reduced biodiversity with a total of 125 species (66 amphibians and 59 reptiles) exclusive or restricted to the region, and few species shared between systems. We find that biogeographical patterns follow a natural topographic disposition above 200 m in elevations. At the lower elevation cut off, there are 118 species (26 amphibians and 92 reptiles) shared among two or more of the studied mountain systems, suggesting a common origin and dispersal events, despite what seem to be topographic barriers. Biogeographical relationships support a topographic disposition of the region with close associations between the islands of Trinidad and Tobago, the Paria Range and the Turimiquire Massif, and close associations between the Sierra Nevada de Santa Marta and the Sierra de San Luis. Overall, the biogeographic relationships between amphibians and reptiles are similar. Species diversity in the eastern Caribbean region is less rich than in the west. This study includes the first herpetological surveys at the two easternmost mountains (Cerro La Cerbatana and Campeare) belonging to the Paria Range biogeographic unit, and aims to contribute to a better understanding of the rich biodiversity of the region.
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Rios-López, Neftalí. "Effects of increased salinity on tadpoles of two anurans from a Caribbean coastal wetland in relation to their natural abundance." Amphibia-Reptilia 29, no. 1 (2008): 7–18. http://dx.doi.org/10.1163/156853808783431451.
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Abstract Many amphibians depend on wetland ecosystems for reproduction and survival, and coastal wetlands are not the exception. Recent advances on climate change research predict a reduction in land cover of coastal wetlands due to sea-level rise in response to global warming. Although this scenario will contribute to further amphibian population declines worldwide the impacts of sea-level rise and its related salt water intrusion on anuran assemblages in coastal wetlands remain largely unknown. I documented patterns of abundance of the native Caribbean white-lipped frog (Leptodactylus albilabris) and the introduced marine toad (Bufo marinus) along an inland-to-coastal salinity gradient in Puerto Rico. In addition, I investigated the effects of increasing salinity on larval growth and survival to metamorphosis in L. albilabris and B. marinus in laboratory experiments. In the field, relative abundance of adults of L. albilabris decreased with increasing salinity, while B. marinus showed the opposite pattern. Laboratory experiments with L. albilabris and B. marinus revealed that percentage of larvae surviving to metamorphosis in both species was greatly reduced in 22-25% seawater (8 ppt), which is within salinity levels found in their natural distribution. In this salinity level, the native L. albilabris showed ∼100% metamorphosis failure while the introduced B. marinus showed ∼60% metamorphosis failure. The reduction in metamorphosis was due to high mortality in L. albilabris and was accompanied with morphological abnormalities in B. marinus. Tadpoles of only L. albilabris reared for four weeks showed significant weight loss at 8 ppt, but showed no difference in length. These results suggest that anuran tadpoles may be living near their physiological limit for salinity in the studied wetland. Conservation implications are profound, however, as salt water intrusion and urban encroaching inland may result in anuran population replacement, from native species to introduced species in this wetland.
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Berlan, J., Y. Besace, G. Pourcelot, and P. Cresson. "Addition d'organocuprates aux oxazolidines chirales α-β ethyleniques : I - resultats - effets de sel et de solvant." Tetrahedron 42, no. 17 (January 1986): 4757–65. http://dx.doi.org/10.1016/s0040-4020(01)82056-1.
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Ronco, G., J. P. Petit, R. Guyon, and P. Villa. "Mécanisme de solvolyse descis- ettrans-(p-toluènesulfonates) d'aryl-2-cyclopentyle I. Etude de la première étape de la solvolyse: effets isotopiques de l' atone de deutérium en position 2, effets de sel basique et effet spécial de sel." Helvetica Chimica Acta 71, no. 3 (May 4, 1988): 648–57. http://dx.doi.org/10.1002/hlca.19880710319.
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Langevin, René, and Angélique Laurent. "Effets d’un programme fondé sur l’apprentissage socioémotionnel sur les compétences socio-émotionnelles d’élèves fréquentant une école francophone en milieu minoritaire." Journal of Quality in Education 13, no. 22 (November 20, 2023): 142–60. http://dx.doi.org/10.37870/joqie.v13i22.388.
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Cette recherche vise à explorer les effets d’un programme fondé sur le Social and Emotional Learing (Collaborative for Academic Social and Emotional Learning, 2020) connu en français sous le terme apprentissage socio-émotionnel (ASÉ) sur le développement des compétences socio-émotionnelles d’un groupe d’élèves fréquentant une école francophone en milieu minoritaire. L’échantillon est composé de 40 élèves âgés entre 10 et 12 ans. Tous ont été évalués à l’aide de la version en français du questionnaire Social Skills Improvement System - Social Emotional Learning (SSIS-SEL) (Gresham et al., 2017) à deux reprises (avant et après le programme) et 30 d’entre eux ont participé au programme. Ce programme est composé des cinq domaines de compétences du Collaborative for Academic, Social, and Emotional Learning (2020) à savoir : 1) la conscience de soi, 2) l’autogestion, 3) la conscience sociale, 4) les compétences relationnelles et 5) la prise de décision responsable. Les résultats indiquent que la première hypothèse est partiellement confirmée car contrairement aux élèves de 6e année du groupe expérimental ceux du groupe expérimental de 5e année n’ont pas améliorer de façon significative trois de cinq compétences de base de l’ASÉ soit 3) la conscience sociale, 4) les compétences relationnelles et 5) la prise de décision responsable. De même, les résultats de la deuxième hypothèse sont également partiellement confirmés. On observe dans ce cas, plus de résultats significatifs aux échelles du questionnaire SSIS-SEL chez les élèves de 5e année du groupe expérimental que chez ceux de 6e année du groupe expérimental et ce, comparativement aux élèves de 6e année du groupe témoin. Les résultats montrent par ailleurs que l’ASÉ peut entraîner de façon général l’amélioration des compétences socio-émotionnelles des élèves des deux groupes expérimentaux.
Dissertations / Theses on the topic "Amphibiens – Effets du sel"
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Lorrain-Soligon, Léa. "Conséquences de l’augmentation de la salinité sur la faune des marais littoraux : le cas des amphibiens." Electronic Thesis or Diss., La Rochelle, 2023. http://www.theses.fr/2023LAROS026.
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Les zones humides côtières sont caractérisées par des variations spatiales, temporelles, et liées aux changements globaux, de la salinité. Ces variations de salinité peuvent influencer négativement la biodiversité très riche des zones humides côtières. C’est particulièrement le cas pour les amphibiens, caractérisés par un tégument perméable et de faibles capacités de dispersion. Si la sensibilité des amphibiens à la salinité est bien connue, elle a majoritairement été déterminée dans le cadre du salage des routes, sur des communautés qui sont naïves à l’exposition au sel. Néanmoins, les populations côtières d’amphibiens, exposées régulièrement à ces variations de salinité, devraient présenter une tolérance à ce paramètre environnemental en réponse à des processus d’adaptation locale. Nous avons examiné comment la salinisation des milieux côtiers influence l’écologie, la physiologie, le comportement et le développement des amphibiens côtiers. A tous les niveaux d’intégration (communautés, populations, individus), nous avons montré des impacts négatifs de l’exposition au sel, affectant la composition de la communauté, la distribution des individus, leur croissance, leur développement, leur physiologie et leur comportement. Cependant, les communautés, les individus adultes, et les larves, sont tous capables de résilience physiologique et comportementale au travers de mécanismes de compensation. Nos travaux ont permis une meilleure compréhension des effets des variations de la salinité sur la biodiversité des zones humides côtières, et d’apporter des pistes de gestion pour compenser les effets de ce changement globalCoastal wetlands are characterized by spatial, temporal, and global change-related variations in salinity. These variations in salinity can negatively impact the biodiversity of coastal wetlands. This is particularly the case for amphibians, characterized by a permeable integument and low dispersal abilities. Although amphibians’ sensitivity to salinity is well known, it has mainly been studied in the context of road de-icing salt, in communities that are naive to salt exposure. Nevertheless, coastal populations of amphibians, regularly exposed to these salinity variations, should express a higher tolerance to this environmental parameter in response to local adaptation processes. We investigated how salinization of coastal environments influences the ecology, physiology, behaviour and development of coastal amphibians. At all levels of integration (community, population, individual), we have shown negative impacts of salt exposure, affecting the composition of the community, the distribution of individuals, their growth, their development, their physiology and their behaviour. However, communities, adult individuals, and larvae all expressed physiological and behavioural resilience through compensatory mechanisms. Our work has led to a better understanding of the effects of salinity variations on coastal wetlands’ biodiversity, and to provide management options to compensate for the effects of this global change
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Mandrillon, Anne-Lise. "Effets de substances indicatrices d’un risque de prédation sur le comportement, la morphologie et les traits d’histoire de vie de la grenouille rousse (Rana temporaria) et du crapaud commun : modulation par un herbicide, l’amitrole." Rennes 1, 2007. http://www.theses.fr/2007REN1S076.
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Chez les larves d’amphibiens, l’estimation du risque de prédation et la mise en place de réponses anti-prédatrices adaptatives dépendent étroitement de la détection des signaux chimiques libérés par les prédateurs et (ou) les congénères blessés. Toutefois, de tels processus à support olfactif peuvent être particulièrement vulnérables à la présence de contaminants chimiques en milieu aquatique. La thèse vise donc à évaluer les effets d’expositions embryo-larvaires simples et combinées à un herbicide triazole (amitrole) et à différents types de signaux chimiques indicateurs d’un risque de prédation sur le comportement, la morphologie et les traits d’histoire de vie de la grenouille rousse (Rana temporaria) et du crapaud commun (Bufo bufo). Cette approche expérimentale a donné lieu à une série d’articles scientifiques, et à la suggestion de nouvelles pistes de recherche et mesures relatives à la conservation des amphibiensIn larval amphibians, predation risk assessment and adaptive anti-predator responses are tightly dependent on the detection of chemical signals released from predators and (or) injured conspecifics. However, such olfactory-mediated processes can be particularly vulnerable to the presence of waterborne chemical contaminants. Thus, the thesis aims to evaluate the behavioural, morphological and life-historical effects of single and combined embryo-larval exposures to a triazole herbicide (amitrole) and to different types of chemical signals indicative of a predation risk in the common frog (Rana temporaria) and the common toad (Bufo bufo). This experimental approach has resulted in a series of scientific articles, and the suggestion of some new research prospectives and measures relative to amphibians’ conservation
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Ciolek, Eric. "Effets de la triiodothyronine endogène et exogène, et du clofibrate sur les peroxysomes hépatiques des amphibiens anoures." Nancy 1, 1991. http://docnum.univ-lorraine.fr/public/SCD_T_1991_0050_CIOLEK.pdf.
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La révélation in situ de l'activité de la catalase par cytochimie ultrastructurale a permis de suivre l'évolution des peroxysomes hépatiques au cours de la métamorphose naturelle ou induite par la triiodothyronine (t#3) chez les amphibiens anoures. Les activités enzymatiques de la catalase et de diverses oxydases peroxysomales ont été analysées par dosages spectrophotometriques pendant le développement post-embryonnaire d'alytes obstetricans et de xenopus laevis. Des différences s'établissent dans le comportement des peroxysomes hépatiques entre les animaux dont la métamorphose s'accompagne d'un changement d'habitat (alyte) et ceux qui restent aquatiques (xenope). Le traitement des larves d'alytes obstetricans a permis de montrer que les peroxysomes étaient sensibles à l'action de la t#3. Les effets du clofibrate sur les peroxysomes hépatiques ont été recherchés chez les amphibiens anoures. Cette substance est sans effet apparent sur les peroxysomes des larves d'alytes obstetricans. Elle provoque une prolifération des peroxysomes hépatiques ainsi qu'une induction de leurs enzymes en particulier celles de la -oxydation chez rana esculenta adulte (espèce terrestre) et n'induit que les activités enzymatiques peroxysomales dans le foie de xenopus laevis adulte (espèce aquatique). L'expression de la catalase et de la d-aminoacide oxydase post-embryonnaire a été étudiée chez ces différentes espèces d'amphibiens par électrophorèse monodimensionnelle et western blotting à partir des protéines extraites de fractions hépatiques enrichies en peroxysomes.
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Decamp, Antoine. "Etude des conditions d’accumulation et de production de polysaccharides solubles (ou exopolysaccharides - EPS) chez des microalgues marines cultivées en photobioréacteur." Thesis, Nantes, 2020. http://www.theses.fr/2020NANT4035.
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Cette thèse porte sur l’étude des mécanismes de synthèse des exopolysaccharides de Porphyridium cruentum et l’optimisation de leurs productions en photobioréacteur. Afin de répondre à cet objectif, l’effet de la salinité et de la lumière ont principalement été étudiés. La salinité est un paramètre influençant fortement le métabolisme des carbohydrates de Porphyridium cruentum favorisant la production de biomasse pour une salinité médiane, l’accumulation d’amidon en condition hypo-osmotique et l’accumulation de glycosides (plus particulièrement de floridoside) en condition hyper-osmotique. Le MRPA (Mean rate of Photon Absorption) a été utilisé afin d’évaluer le comportement de la microalgue rouge en condition de stress lumineux ainsi qu’en photo limitation. La première partie de cette étude a permis de montrer que Porphyridium cruentum est un organisme sensible à la lumière, présentant une section efficace d'absorption 7 fois inférieure à la microalgue verte Chlorella vulgaris. Dans une deuxième partie, différents niveaux de stress lumineux ont été imposés à la microalgue rouge, les résultats ont démontré qu’à partir d’une valeur seuille l’augmentation du MRPA permet d’accélérer fortement la production de polysaccharides (sous forme d’amidon et de BPS dans un premier temps et sous forme de RPS lors d’un stress prolongé). L’association du stress osmotique et lumineux a permis de développer un protocole permettant de valoriser la biomasse de Porphyridium cruentum à façon dans le but de produire en condition hyper-osmotique contrôlée du floridoside ou en condition hypo-osmotique pour des MRPA élevées des polysaccharidesThis thesis concerns the study of the mechanisms implicated in Porphyridium cruentum exopolysaccharides synthesis and the optimization of their production in photobioreactors. In order to achieve this objective, the effect of salinity and light were mainly studied. Salinity is a parameter which affect the carbohydrates metabolism of Porphyridium cruentum favouring biomass production at median salinity, starch accumulation in hypo-osmotic conditions and glycoside accumulation (more particularly floridoside) in hyper-osmotic conditions. MRPA (Mean rate of Photon Absorption) was used to evaluate the behaviour of red microalgae in light stress conditions and in photo limitation. The first part of this study showed that Porphyridium cruentum is a light-sensitive organism with an effective absorption cross section 7 times smaller than the green microalgae Chlorella vulgaris. In the second part, different levels of light stress were imposed on the red microalgae, the results showed that from a threshold value the increase in MRPA allows to strongly accelerate the production of polysaccharides (in the form of starch and BPS in a first step and in the form of RPS during a prolonged stress).The combination of osmotic and light stress has made it possible to develop a protocol to valorise the biomass of Porphyridium cruentum in order to produce floridoside in controlled hyper-osmotic conditions or polysaccharides for hypo-osmotic conditions coupling with high MRPA
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Bouraïma-Madjèbi, Saliou. "Influence de la salinité (NaCl) sur la croissance et la photosynthèse des Mils (Pennisetum) d'origines géographiques différentes." Paris 11, 1986. http://www.theses.fr/1986PA112325.
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La réponse à la salinité du Mil pénicillaire à chandelle a été étudiée au cours de ce travail. Nous avons cherché à mettre en évidence des caractères physiologiques et biochimiques de résistance au sel de Pennisetum typhoïdès (L. ) cv « Drôo Zarzis », écotype tunisien des terrains salés cultivés dans les conditions de laboratoire et comparé son comportement à celui de 5 autres Pennisetum d’origines géographiques différentes. Sur le plan de la croissance, P. Typhoïdès Drôo Zarzis se démarques des autres mils par sa tolérance et sa tendance halophyte ; P. Violaceum est très sensible : le comportement des autres génotypes est intermédiaire à ces deux extrêmes. L’analyse des compositions minérales (K+ / Na+) et organiques confirment le comportement particulier de P. Typhoïdès Drôo Zarzis et explique la sensibilité de P. Violaceum. Ce résultat suggère que la compartimentation des ions principalement de K+ peut être un mécanisme de la résistance au sel. La sensibilité serait due à une toxicité ionique. A la limitation photosynthétique de mils par le traitement salin, s’oppose une stimulation de la capacité maximale des enzymes clés du métabolisme C4 du carbone (PEPC RuBPC et NAPD-EM). L’approche immunologique montre sans ambiguïté que la stimulation de la capacité PEPC et NADP-EM est associée à une augmentation de la quantité des protéines enzymatiques. Elle révèle pour la première fois chez le genre Pennisetum que l’augmentation de la capacité RuBPC est due à l’accroissement de la protéine enzyme sans modifier l’activité spécifique. La forte stimulation de la capacité GS cytosolique chez P. Typhoïdès Drôo Zarzis est modulée par l’ambiance intracellulaire et la compartimentation des ions et sa tendance halophyte. Ce résultat indique que la GS cytosolique serait un bon marqueur de la tendance halophyte. Il y a effet hétérosis pour la photosynthèse nette et la teneur en amidon chez P. Typhoïdès « Tiotandé mâle stérile ». Ceci est complètement modifié par le traitement salin, ce qui suggère l’utilisation de ces génotypes dans la recherche de l’hétérosis en conditions salines avec un des mils tolérants. En définitive, ce travail démontre l’utilité d’étude comparative avec des génotypes délibérément sélectionnés pour leur différence au sel dans l’élucidation des mécanismes gouvernant la tolérance des mils au stress salin. La recherche de l’hétérosis en conditions salines peut être obtenue à l’aide de P. Tiotandé mâle stérile avec P. Typhoïdès Drôo ZarzisThe effects of salinity were studied in six genotypes of pearl millet. We have attempted to characterize the resistance to salinity of Pennisetum typhoides Drôo Zarzis, a Tunisian ecotype from a saline habitat cultivated in controlled conditions and to compare its behaviour with five other Pennisetum genotypes from different geographic origins. The growth behaviour of P. Typhoides Drôo Zarzis can be characterized by a high tolerance to salt (halophytic response). P. Violaceum shows the least resistance to saline conditions, while the 4 other genotypes show intermediate response to the 2 extremes. An analysis of the mineral and organic composition was compatible with the halophytic tendency of P. Typhoides Drôo Zarzis and could explain the sensitivity ta saline conditions of P. Violaceum. The results provide evidence that there is a definite specific ion effect which is related to salt sensitivity. It is suggested that superior compartmentation of ions, principally K+ may be a mechanism of salt resistance. An enhancement in the maximum capacities of the key-enzymes of C4 metabolism (PEPC, RuBPC + NADP-EM) has been measured under limiting photosynthetic conditions related to the saline treatment. An immunological approach clearly showed that this stimulation in the capacity of PEPC and NADP-EM is due to an increase in the total quantity of the enzymes. We have also demonstrated for the first time in Pennisetum that an increased in RuBPC capacity is related to an increase in the enzyme amount but its specific activity remains constant. The marked increase in cytosolic GS observed in P. Typhoides Drôo Zarzis is modulated by the intracellular environment, namely the ionic compartmentation related to the halophytic nature of the genotype. With regards to the cytosolic GS1 this isœnzyme might be interpreted as a marker of halophyty. An heterosis effect is noted in the net photosynthesis and starch content for P. Typhoides Tiotandé a "male sterile". Lts behaviour is completely modified in saline conditions. Finally this work demonstrate the utility of comparative experiments with related genotypes deliberately selected for differences in salt resistance for elucidation of mechanisms governing the response of Pennisetum to salt stress. The research of heterosis in saline condition could be obtained with crossing P. Typhoides "Tiotandé male sterile" and one of salt tolerant genotype principally P. Typhoides Drôo Zarzis
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Grondin, Marie-Ève. "Rôle des enképhalines et des récepteurs mu opiacés dans l'appétit pour le sel." Master's thesis, Université Laval, 2006. http://hdl.handle.net/20.500.11794/18343.
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Landouar-Arsivaud, Lucie. "Recherche de gènes intervenant dans la tolérance au stress salin dans le phloème de céleri (Apium graveolens L. )." Poitiers, 2004. http://www.theses.fr/2004POIT2349.
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"Le stress salin constitue une des contraintes environnementales majeures pour la culture du melon dans le sud de l'Espagne et sur le pourtour du bassin méditerranéen, mais également pour d'autres cultures dans de nombreuses régions du monde (Australie, Etats-Unis). L'obtention de variétés tolérantes est donc un enjeu majeur pour le sélectionneur. La réponse des plantes au stress salin et la mise en place de mécanismes de tolérance passent par la régulation d'un grand nombre de gènes. Le phloème constitue par ailleurs un tissu essentiel pour la vie et le développement des plantes, par le transport à longue distance des photoassimilats, et la transmission d'informations entre les différents organes. L'objectif de cette thèse a été d'identifier des gènes dont l'expression est stimulée par un stress salin, dans le phloème de Céleri branche (Apium graveolens L. Dulce cv. Vert d'Elne). Un traitement au NaCl (300 mM) a été appliqué pendant 3 semaines sur du Céleri cultivé en serre. Une étude physiologique de la réponse des plantes au stress salin (croissance, teneur relative en eau) a été réalisée. Une banque soustractive a été produite à partir des ARNm extraits de phloème de Céleris "stressés" et "témoins". Celle-ci permet d'obtenir uniquement les gènes dont l'expression est stimulée par le stress salin. Parmi les 736 ADNc obtenus et analysés sur membranes par marquage différentiel, 30 ADNc partiels répondent aux deux critères sélectionnés, induction par un stress salin et ce dans le tissu phloèmien. Seuls 3 clones ont été choisis avec notre partenaire, sur le critère de brevatibilité. Les régions promotrices de ces gènes ont été clonées et placées en amont du gène rapporteur GUS (codant la b-glucuronidase) afin de suivre leur profil d'expression chez Arabidopsis thaliana, en réponse à un stress salin. "Salt stress constitutes one of the major environmental constraints for melon culture in the south of Spain and in the mediterranean basin, and for other cultures as well in many regions of the world (Australia, United-States). The availability of tolerant plants is therefore a major goal for breeders. Plant response to salt stress and the development of tolerance mechanisms imply the regulation of a large number of genes. On the other hand, phloem is an essential tissue for plant development allowing long distance transport of photo-assimilates and information transmission between different organs. The aim of this thesis has been to identify genes whose expression is stimulated by salt stress, in Celery phloem (Apium graveolens L. Dulce cv. Vert d'Elne). A salt treatment (300 mM) was applied during 3 weeks on celery grown in the green house. A physiological study of salt stress response in plants (growth, relative water content) was made. A subtractive library was produced from petiole phloem mRNAs extracted from "stressed" and "control" celery. This method isolated exclusively genes whose expression was stimulated by salt stress. Among the 736 cDNAs obtained and analysed on macroarray by differential screening, 30 partial cDNAs met the two selection criteria : salt stress induction and phloem tissue localisation. Only 3 clones were selected with our private partner on the basis of novelty and certification. Promoters of these genes have been cloned and placed upstream of the GUS reporter gene (b-glucuronidase) in order to study their expression profile in Arabidopsis thaliana, in response to salt stress
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Voisin, Aurore. "LES ENKÉPHALINES ET LA NEUROBIOLOGIE DU SEL Caractérisation électrophysiologique, neuroanatomique et fonctionnelle." Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/29978/29978.pdf.
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Les variations de sodium (Na+) extracellulaire sont, chez le rat, détectées par les neurones du noyau préoptique médian (MnPO) grâce à la présence des canaux NaX. Nous voulions tout d’abord étudier les propriétés électriques des neurones senseurs de Na+ du MnPO en réalisant des enregistrements électrophysiologiques. Nous démontrons une augmentation de l’excitabilité des senseurs de Na+ due probablement à une diminution des canaux responsables de l’adaptation de fréquence et une augmentation des canaux responsables de la rectification membranaire dépendante du temps. Comme notre laboratoire a démontré une modulation de l’excitabilité des senseurs de Na+ par le système des enképhalines (ENK) et des récepteurs aux opiacés de type mu (mu-OR) fonctionnels lors d’un déficit sodique aigü, nous voulions démontrer alors un renforcement de cette excitabilité neuronale lors de déplétions sodiques répétées. Nos résultats démontrent que des déplétions sodiques répétées induisent une désensibilisation des neurones senseurs de Na+ et de l’expression des canaux NaX. Toutefois, les senseurs de Na+ montrent une hyperexcitabilité en réponse à trois déficits en Na+ qui semble être modérée par la surexpression fonctionnelle des mu-OR . De ce fait, nous voulions déterminer les régions cérébrales qui libéraient les ENK au MnPO en y injectant un traceur rétrograde fluorescent. Nos données rapportent le noyau parabrachial et le noyau du tractus solitaire comme principales sources ENKergiques au MnPO; le noyau lit de la strie terminale et le noyau paraventriculaire comme sources ENKergiques modérées. Cette relâche d’ENK pourrait initier l’appétit pour le sel en réponse à un déficit sodique. Comme l’appétit pour le sel est un comportement motivé et que certaines études rapportent un renforcement de l’appétit pour le sel appelé sensibilisation au sel, nous voulions alors établir une corrélation entre expression des ENK et/ou des mu-OR dans le circuit de récompense et sensibilisation au sel. Nous montrons que la sensibilisation au sel n’est pas un phénomène universel chez les rats et que celle-ci est corrélée à une diminution de l’expression des mu-OR dans le pallidum ventral (VP). De plus, l’expression des mu-OR dans le VP est un requis essentiel à la mise en place de la sensibilisation au sel.In rats, extracellular sodium (Na+) variations are detected by neurons in the median preoptic nucleus (MNPO) due to the presence of NaX channels. First, we wanted to determine the electrical properties of MnPO Na+ sensor neurons using electrophysiological recordings. We demonstrate an increase in the excitability of Na+ sensors, probably due to a decrease in ionic channels responsible for spike frequency adaptation and an increase in the ionic channels sustaining time-dependent membrane rectification. Since our laboratory demonstrated a modulation of Na+ sensors excitability by enkephalins (ENK) and mu-opioid receptors (mu-OR) system for an acute sodium deficit, so we wanted to demonstrate an enhancement in this neuronal excitability during repeated sodium depletion. Our results demonstrate that repeated sodium depletion induced desensitization of Na+ sensors and NaX channels expression. However, Na+ sensors show a hyperexcitability in response to three Na+ deficits that appears to be mitigated by the overexpression of functional mu-OR. Then, we wanted to determine the brain regions releasing ENK within the MNPO by injecting a fluorescent retrograde tracer. Our data report the parabrachial nucleus and the nucleus of solitary tract as the main ENK sources to MNPO; the bed nucleus of stria terminalis and the paraventricular nucleus as moderate ENK projections. This ENK release could initiate salt appetite in response to sodium deficit. Since salt appetite is a motivated behavior and some studies reported an enhanced salt appetite named salt sensitization, so we wanted to correlate ENK and/or mu-OR expression in reward circuit and salt sensitization. We show that salt sensitization is not a universal phenomenon in rats and that it is correlated with a decreased mu-OR expression in the ventral pallidum (VP). In addition, mu-OR expression in the VP is a fundamental requisite to the development of salt sensitization.
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Ouedraogo, Lazare. "Etude de quelques effets de la métamorphose des amphibiens sur certaines protéines et sur la structure hépatique." Paris 13, 1987. http://www.theses.fr/1987PA132022.
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Ouedraogo, Lazare. "Etude de quelques effets de la métamorphose des amphibiens sur certaines protéines et sur la structure hépatique." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37608621x.
Full textBooks on the topic "Amphibiens – Effets du sel"
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Eliminez le sel retrouvez la forme !: Moins de sel, plus de potassium : La clé de votre santé. Monaco: Alpen éditions, 2007.
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1946-, Haymann Emmanuel, ed. Le sel, un tueur caché. Lausanne: Favre, 2009.
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Waisel, Yoav. Biology of Halophytes. Elsevier Science & Technology Books, 2012.
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Sodium in Agriculture. Chalcombe Publications, 1995.
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(Editor), Donald W. Sparling, Greg Linder (Editor), Christine A. Bishop (Editor), and Sherry Krest (Editor), eds. Ecotoxicology of Amphibians and Reptiles, Second Edition. 2nd ed. CRC, 2009.
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Stille, Mark. Philippines Naval Campaign 1944–45. Bloomsbury Publishing Plc, 2024. http://dx.doi.org/10.5040/9781472856975.
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The forgotten story of the major naval operations conducted in the Philippines by the US and Japanese navies after Leyte Gulf up to the US invasion of Luzon in January 1945. The events that took place in the aftermath of the Battle of Leyte Gulf in October 1944 are often overlooked by military historians. An impressive array of naval operations continued in the Philippines up to January 1945, which included (on the Japanese side) the largest convoys to a contested island during the war, the first kamikaze campaign, and the second largest Imperial Japanese Navy surface operation during the last nine months of the conflict. On the American side, US forces were involved in efforts to cut off Leyte from enemy reinforcement, a massive amphibious invasion off Luzon, and large-scale operations by the Fast Carrier Task Force (TF 38). Expert naval historian Mark Stille throws new light on this often forgotten phase of the Pacific naval war. Among the actions covered are the battles for Ormoc Bay, the invasion of Mindoro, Japanese kamikaze attacks, and US Third Fleet's rampage through the South China Sea between January 10 and 20, 1945. Superb battlescene artworks bring the war at sea and in the air vividly to life, and maps and diagrams guide readers through a range of actions in clear, step-by-step detail.
Book chapters on the topic "Amphibiens – Effets du sel"
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"5 Effets des dépôts de sel." In Le sel, saveur de la Terre, 58–67. EDP Sciences, 2020. http://dx.doi.org/10.1051/978-2-7598-2050-4-008.
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"5 Effets des dépôts de sel." In Le sel, saveur de la Terre, 58–67. EDP Sciences, 2020. http://dx.doi.org/10.1051/978-2-7598-2050-4.c008.
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Meshaka, Walter E., Suzanne L. Collins, R. Bruce Bury, and Malcolm L. McCallum. "Salamanders (Caudata)." In Exotic Amphibians and Reptiles of the United States, 20–24. University Press of Florida, 2022. http://dx.doi.org/10.5744/florida/9780813066967.003.0003.
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This chapter examines salamanders. It begins with mole salamanders, particularly the Western Tiger salamander. This species has a long history of being transported around the United States for all the wrong reasons: initially as fish bait, and presently as part of the pet trade. The effects of human-mediated dispersal and establishment of extralimital populations are evident today in hybrid swarming, species replacement, and confused biogeography. The chapter then looks at lungless salamanders, including the Seal salamander and the Southern two-lined salamander. The Seal salamander is not native to Arkansas. A population was detected in a spring in 2003 and reported in 2004; the colony was derived from northern Georgia in association with the bait market. The Southern two-lined salamander is native to eastern Illinois; however, it is exotic to McKee Creek, Brown County, and LaMoine River, McDonough County, in western Illinois.
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"Chapitre 18. Le sel à Poitiers, les lions en Afrique et autres effets particuliers d’un ciel immobile." In Studia Sententiarum, 251–83. Turnhout, Belgium: Brepols Publishers, 2021. http://dx.doi.org/10.1484/m.ssent-eb.5.126858.
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Holman, J. Alan. "Introductio." In Pleistocene Amphibians and Reptiles in Britain and Europe. Oxford University Press, 1998. http://dx.doi.org/10.1093/oso/9780195112320.003.0005.
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There is disagreement about the time of the beginning of the Pleistocene. For instance, Repenning (1987), a North American, puts the beginning date at 1.9 million ybp. On the other hand, some modern Europeans studying the subject (e.g., Gibbard et al., 1991; Kolfschoten and Meulen, 1986; Roebroeks and Kolfschoten, 1995; Zagwijn, 1985, 1992) consider the epoch to have begun about 2.3 million ybp. The system used here, however, follows Sanchiz (in press), who accepts the official usage of Harland et al. (1990), who put the beginning of the Pleistocene at 1.64 million ybp. Evidence that the Pleistocene ended about 10,000 ybp (Meltzer and Mead, 1983) is widely accepted. This ending date correlates very closely with the terminal extinction of many large land mammal species. The Pleistocene is characterized by climatic oscillations and a series of glacial and interglacial events where great continental ice sheets advanced and retreated many times. The ice sheets were massive forces, sculpting the topography of the land and carrying much sedimentary material, including huge boulders and even megablocks of land up to 4 km in diameter, as far as 250 km in the Canadian prairies (MacStalker, 1977). In Britain and Europe, as well as in North America, the advance and retreat of ice sheets had a marked effect on the distribution of plant and animal life. Huge tracts of habitat were alternately obliterated and reopened several times, but other effects perhaps arc not so well known. For instance, during glacial times, so much atmospheric water was tied up in the formation of the ice that sea levels worldwide lowered markedly. On the other hand, sea levels rose during interglacial times when water was melting off the ice sheets. The most interesting and controversial biological event that took place in the Pleistocene was the sudden, almost worldwide, extinction of large land mammals, and to a lesser extent birds, that took place by the end of the epoch 10,000 years ago. At least 200 mammalian genera became extinct, among them large herbivores, the carnivores that preyed on them, and the scavengers that fed on the remains of both groups.
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Brockes, Jeremy. "Effect of retinoic acid on regenerating urodele limbs." In Retinoids in Normal Development and Teratogenesis, 113–18. Oxford University PressOxford, 1992. http://dx.doi.org/10.1093/oso/9780198547709.003.0009.
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Abstract Limb regeneration is an important system for evaluating the morphogenetic effects of retinoids. In turn, the activity of retinoids on epimorphic regeneration promises to shed much light on basic aspects of this process. In this brief review I shall outline the main events of limb regeneration and the effects of retinoic acid (RA) on axial specification, as well as discussing hypotheses for the mechanism of these effects and the prospects offered by the identification of nuclear RA receptors in the limb and its regenerate. I have not considered the effects on avian limb development in this account because these have been considered elsewhere in this volume. The urodele (tailed) amphibians are vertebrates that can regenerate their limbs as adults, e.g. the newt and the axolotl. In anurans such as the frog, the ability to regenerate a limb is lost progressively at around the stage of metamorphosis, but tadpole limb regeneration has been studied and was the system in which the effects of retinoids on limb morphogenesis were discovered (Niazi and Saxena 1978). After amputation of the urodele limb at any level on the proximodistal axis (PD) the epidermal cells at the circumference migrate rapidly over the cut surface to seal the limb. They form a structure called the wound epidermis, which is thought to play an important role in outgrowth of the regenerate (Wallace 1981). The wound epidermis is formed, at least to the extent of monolayer formation, during the first 12-24 hours. During the subsequent period, the mesenchymal tissue underlying the wound epidermis in the vicinity of the amputation plane undergoes an important progressive change in identity. This process, loosely referred to as dedifferentiation (Ferretti and Brockes 1991), results in the local formation of blastemal cells, the progenitors of the mesenchymal tissue of the regenerate. The blastemal cells divide, initially under control of the nerve supply, and subsequently undergo differentiation and morphogenesis to form the regenerate.
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Mulloy, Garren. "Defenders of Japan Present and Future." In Defenders of Japan, 191–264. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780197606155.003.0005.
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Contemporary Japanese defense involves greater integration of civilian and military aspects and interdependence of domestic, regional, and global aspects than in previous periods. This chapter identifies how the Japan Self-Defense Forces adapted, in material ways, but also in recruitment, training, culture, and civil cooperation, with capabilities adapting to emergent challenges, particularly from China and North Korea. Civil-military and US-Japan alliance cooperation reached ultimate fulfilment in the aftermath of the 2011 earthquake and tsunami, when the Forces demonstrated their extensive disaster relief and civil support skills honed through decades of domestic and overseas missions, as well as the inherent value of US alliance training and international engagement for Japan’s national and human security. The importance of building international relations was evident as Abe Shinzo sought to buttress Japan’s alliance with new partnerships and cooperative mechanisms, including the Quad and Free and Open Indo-Pacific, within which the Forces were expected to play prominent symbolic and functional roles. The irony is that the Forces reconfigured with more mobile, agile, and amphibious capabilities, for increased international roles as Japan’s peacekeeping and other overseas missions were withering, regional security challenges re-focusing resources and efforts towards near and national defense.
Conference papers on the topic "Amphibiens – Effets du sel"
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Matveev, Konstantin I., and Zachary J. Malhiot. "Construction and Testing of Radio-Controlled Power Augmented Ram Model." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41136.
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Heavy-payload Power Augmented Ram vehicles represent a new class of amphibious transportation means. In the static and low-speed operational regimes, these machines utilize a skirtless pressurized air cushion generated by front jet propulsors. In the high-speed motion, the aerodynamic lift augmented in ground effect becomes the dominant support. The construction of a small-scale radio-controlled Power Augmented Ram model is described. Results of initial static and self-propelled tests on solid surfaces are presented. Future research work and possible full-scale applications are discussed.
Reports on the topic "Amphibiens – Effets du sel"
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Yaron, Zvi, Abigail Elizur, Martin Schreibman, and Yonathan Zohar. Advancing Puberty in the Black Carp (Mylopharyngodon piceus) and the Striped Bass (Morone saxatilis). United States Department of Agriculture, January 2000. http://dx.doi.org/10.32747/2000.7695841.bard.
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Both the genes and cDNA sequences encoding the b-subunits of black carp LH and FSH were isolated, cloned and sequenced. Sequence analysis of the bcFSHb and LHb5'flanking regions revealed that the promoter region of both genes contains canonical TATA sequences, 30 bp and 17 bp upstream of the transcription start site of FSHb and LHb genes, respectively. In addition, they include several sequences of cis-acting motifs, required for inducible and tissue-specific transcriptional regulation: the gonadotropin-specific element (GSE), GnRH responsive element (GRE), half sites of estrogen and androgen response elements, cAMP response element, and AP1. Several methods have been employed by the Israeli team to purify the recombinant b subunits (EtOH precipitation, gel filtration and lentil lectin). While the final objective to produce pure recombinantGtH subunits has not yet been achieved, we have covered much ground towards this goal. The black carp ovary showed a gradual increase in both mass and oocyte diameter. First postvitellogenic oocytes were found in 5 yr old fish. At this age, the testes already contained spermatozoa. The circulating LH levels increased from 0.5 ng/ml in 4 yr old fish to >5ng/ml in 5 yr old fish. In vivo challenge experiments in black carp showed the initial LH response of the pituitary to GnRH in 4 yr old fish. The response was further augmented in 5 yr old fish. The increase in estradiol level in response to gonadotropic stimulation was first noted in 4 yr old fish but this response was much stronger in the following year. In vivo experiments on the FSHb and LHb mRNA levels in response to GnRH were carried out on common carp as a model for synchronom spawning cyprinids. These experiments showed the prevalence of FSHP in maturing fish while LHP mRNA was prevalent in mature fish, especially in females. The gonadal fat-pad was found to originate from the retroperitoneal mesoderm and not from the genital ridge, thus differing from that reported in certain amphibians This tissue possibly serves as the major source of sex steroids in the immature black carp. However, such a function is taken over by the developing gonads in 4 yr old fish. In the striped bass, we described the ontogeny of the neuro-endocrine parameters along the brain-pituitary-gonadal axis during the first four years of life, throughout gonadal development and the onset of puberty. We also described the responsiveness of the reproductive axis to long-term hormonal manipulations at various stages of gonadal development. Most males reached complete sexual maturity during the first year of life. Puberty was initiated during the third year of life in most females, but this first reproductive cycle did not lead to the acquisition of full sexual maturity. This finding indicates that more than one reproductive cycle may be required before adulthood is reached. Out of the three native GnRHs present in striped bass, only sbGnRH and cGnRH II increased concomitantly with the progress of gonadal development and the onset of puberty. This finding, together with data on GtH synthesis and release, suggests that while sbGnRH and cGnRH II may be involved in the regulation of puberty in striped bass, these neuropeptides are not limiting factors to the onset of puberty. Plasma LH levels remained low in all fish, suggesting that LH plays only a minor role in early gonadal development. This hypothesis was further supported by the finding that experimentally elevated plasma LH levels did not result in the induction of complete ovarian and testicular development. The acquisition of complete puberty in 4 yr old females was associated with a rise in the mRNA levels of all GtH subunit genes, including a 218-fold increase in the mRNA levels of bFSH. mRNA levels of the a and PLH subunits increased only 11- and 8-fold, respectively. Although data on plasma FSH levels are unavailable, the dramatic increase in bFSH mRNA suggests a pivotal role for this hormone in regulating the onset and completion of puberty in striped bass. The hormonal regulation of the onset of puberty and of GtH synthesis and release was studied by chronic administration of testosterone (T) and/or an analog of gonadotropin-releasing hormone (G). Sustained administration of T+G increased the mRNA levels of the PLH subunit to the values characteristic of sexually mature fish, and also increased the plasma levels of LH. However, these changes did not result in the acceleration of sexual maturation. The mRNA levels of the bFSH subunit were slightly stimulated, but remained about 1/10 of the values characteristic of sexually mature fish. It is concluded that the stimulation of FSH gene expression and release does not lead to the acceleration of sexual maturity, and that the failure to sufficiently stimulate the bFSH subunit gene expression may underlie the inability of the treatments to advance sexual maturity. Consequently, FSH is suggested to be the key hormone to the initiation and completion of puberty in striped bass. Future efforts to induce precocious puberty in striped bass should focus on understanding the regulation of FSH synthesis and release and on developing technologies to induce these processes. Definite formulation of hormonal manipulation to advance puberty in the striped bass and the black carp seems to be premature at this stage. However, the project has already yielded a great number of experimental tools of DNA technology, slow-release systems and endocrine information on the process of puberty. These systems and certain protocols have been already utilized successfully to advance maturation in other fish (e.g. grey mullet) and will form a base for further study on fish puberty.