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| Registros recuperados: 126 | |
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| Royer, J; Seguineau, Catherine; Park, K; Pouvreau, Stephane; Choi, K; Costil, K. |
| Two methods were used to estimate the reproductive output of female Pacific oysters reared in Normandy: histology with image analysis and ELISA (Enzyme-Linked lmmunoSorbent Assay) which allowed the quantification of egg protein. Condition indices, gonad area and gametogenetic stages of the oysters were determined in the entire population (males and females) between May and October 2005. All investigations were performed in 3 age classes: oysters in their first, second or third years (corresponding to spat, half-grown and market-sized oysters, respectively). Both quantitative histology and ELISA provided similar results in terms of reproductive effort (illustrated by the gonado-somatic index, GSI) except during the GSI drop, corresponding to spawning, which... |
| Tipo: Text |
Palavras-chave: Reproductive effort; Image analysis; Gametogenetic cycle; ELISA; Crassostrea gigas; Condition index. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4305.pdf |
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| Lelievre, Stephanie; Antajan, Elvire; Vaz, Sandrine. |
| One of the problems concerning studies of fish egg distribution is the weak spatial and temporal resolution due to the workload that examination of a large number of samples would demand. Recently, the development of a new laboratory imaging system, the ZooScan, capable of obtaining relatively good resolution images enables automated zooplankton identification using supervised learning algorithms. This new approach was applied to formalin-fixed fish egg samples collected during French winter IBTS (International Bottom Trawl Surveys) in the Eastern English Channel and the Southern North Sea. Fish egg spatial distributions of seven species based on the microscope and ZooScan identifications were compared. Abundance and distribution maps of winter-spawning... |
| Tipo: Text |
Palavras-chave: Fish eggs; ZooScan; Image analysis; Supervised learning method; Interpolated map. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00074/18552/16103.pdf |
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| Lagardere, Françoise; Troadec, Herve. |
| Close similarities have been found between the otoliths of sea-caught and laboratory-reared larvae of the common sole Solea solea (L.), given appropriate temperatures and nourishment of the latter. But from hatching to mouth formation. and during metamorphosis, sole otoliths have proven difficult to read because the increments may be less regular and low contrast. In this study, the growth increments in otoliths of larvae reared at 12 degrees C were counted by light microscopy to test the hypothesis of daily deposition, with some results verified using scanning electron microscopy (SEM), and by image analysis in order to compare the reliability of the 2 methods in age estimation. Age was first estimated (in days posthatch) from light micrographs of whole... |
| Tipo: Text |
Palavras-chave: Larval sole; Solea solea; Otolith; Daily increment; Validation; Image analysis. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00337/44785/44488.pdf |
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| De Verdal, Hugues; Vandeputte, Marc; Pepey, Elodie; Vidal, Marie-odile; Ouedraogo, C; Canonne, Marc; D'Cotta, Helena; Baroiller, Jean Francois; Baras, E; Chatain, Beatrice. |
| The present study aimed to develop nondestructive methods to accurately follow the growth of fish larvae and post-larvae. European sea bass (Dicentrarchus labrax) aged 71-100 days post fertilization (dpf; 20-419 mg) and Nile tilapia (Oreochromis niloticus) aged 14 dpf (10-25 mg) were used as model species. Several measurements were performed on digital pictures of larvae to model body weight. Using body surface area, contour, length and depth, it was possible to estimate accurately the body weight of young European sea bass and Nile tilapia (r² of 0.98 and 0.95, respectively). |
| Tipo: Text |
Palavras-chave: Image analysis; Body weight; Surface area; European sea bass; Nile tilapia. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00205/31619/30045.pdf |
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| Neaud-masson, Nadine; Lefebvre, Alain; Belin, Catherine; Gauthier, Emilie; Huguet, Antoine; Szidon, Antoine; Lefebvre, Arnaud; Cuvelliez, Rémi. |
| This deliverable includes several documents that reflect the operational implementation of the tool FlowCAM / ZooPhytoImage in the framework of REPHY. Among these documents, three reports make an assessment of the entire year 2015, which is not the case with other documents (Master 2 report issued in spring 2015, and minutes of meetings over the year). This summary will be limited to the findings of the three reports providing an updated view of the implementation of the tool. Work completed in 2015 for the operational implementation. The many scans performed in 2015 with the three FlowCAM present at Ifremer (Boulogne‐sur‐Mer, Arcachon and Nantes) allowed, one hand to feed the training sets of the tool FlowCAMZoo/PhytoImage, the other test its routine use.... |
| Tipo: Text |
Palavras-chave: Phytoplancton; FlowCAM; Zoo/PhytoImage; Numérisation; Analyse d’images; Set d’apprentissage; Outil de reconnaissance; Architecture de données; Bancarisation; Quadrige; Phytoplankton; FlowCAM; Zoo/PhytoImage; Scanning; Image analysis; Training set; Recognition tool; Data architecture; Banking; Quadrige. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00363/47413/47409.pdf |
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| Ardhuin, Fanny; Mercier, G; Collard, F; Garello, R. |
| A methodology is proposed for the semiautomatic detection, characterization, and classification of slicks detected in C-band Synthetic Aperture Radar (SAR). For the first detection step, automatic algorithms were tested on Environmental Research Satellite (ERS) and Environmental Satellite (EnviSat) images acquired during the Prestige tanker accident. These tests reveal that simple filter or segmentation methods efficiently detect slicks with high contrasts and simple shapes, while a new and more complex multiscale method is able to detect a wider range of slicks. The characteristics of automatically detected slicks are then combined with meteooceanic data in order to eliminate slicks related to wind anomalies and current fronts. The data suggest that... |
| Tipo: Text |
Palavras-chave: Synthetic aperture radar SAR; Satellite measurement; Oil pollution; Image analysis. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-1132.pdf |
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| Gerard, Andre; Naciri, Yamama; Peignon, Jean-marie; Ledu, Christophe; Phelipot, Pascal; Noiret, Christophe; Peudenier, Isabelle; Grizel, Henri. |
| For determination of ploidy levels in bivalves, three techniques are now routinely used: karyological determination. microfluorimetry and flow cytometry. This paper proposes an alternative technique which is based on determination of the optical density (OD) of stained nuclei using image analysis. A karyological and image analysis comparative experiment conducted on juveniles of Crassostrea gigas (Thunberg) and Ruditapes philippinarum (Adam & Reeve) is described and highlights the advantages of the image analysis technique. Initially developed on C. gigas and R. philippinarum, the image analysis method was easily extended to other bivalve species and to different developmental stages, as demonstrated by two experiments conducted on Ostrea edulis (L.).... |
| Tipo: Text |
Palavras-chave: Estimation bivalve triploidy; Image analysis; Triploid; Genetic; Crassostrea gigas; Oysters. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/1994/publication-3200.pdf |
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| Girard, Fanny; Fisher, Charles R.. |
| Cold-water corals form high biodiversity habitats in the deep sea. They are generally long-lived, slow-growing, and thus particularly vulnerable to anthropogenic impact. We used high-definition imagery to quantify the impact and assess the recovery of deep-sea corals that were affected by the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. Over three hundred Paramuricea spp. colonies were imaged yearly between 2011 and 2017 at five sites, and the images were digitized to quantify health, hydroid overgrowth, identify branch loss, and track recovery patterns. Although the median level of impact decreased after 2011 at all impacted sites, it has been stable since then and remained higher than at the reference sites. Recovery depended on the initial... |
| Tipo: Text |
Palavras-chave: Anthropogenic impact; Recovery; Octocoral; Image analysis; Paramuricea biscaya. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00454/56558/58268.pdf |
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| Enriquez-diaz, M.; Pouvreau, Stephane; Chavez-villalba, J.; Le Pennec, M.. |
| The progress of gametogenesis was studied in oysters Crassostrea gigas having the same origin (Tremblade), but cultured during 1 year in two distinctive French marine areas, the Baie des Veys and Marennes-Ol,ron. We assessed seasonal changes in the reproduction cycle on the basis of stereological techniques to estimate reproductive investment and measurement of gonad evolution area by quantitative histology. From a qualitative point of view, both oyster groups presented typical reproductive stages, but showed differential timing, in particular during the sequence of spawning and duration of the re-absorption stage. Oysters in Baie des Veys had a single partial spawning in August and a re-absorption stage that extended until winter. Oysters in... |
| Tipo: Text |
Palavras-chave: Stereology; Reproductive investment; Pacific oysters; Image analysis; Gametogenesis; Crassostrea gigas. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7300.pdf |
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| Grosjean, Philippe; Wacquet, Guillaume. |
| This report details the work accomplished to enhance the Zoo/PhytoImage software to optimize its use for the analysis of phytoplankton samples in general, but more particularly, in the framework of an operational survey of coastal seawater (REPHY, IFREMER). Zoo/PhytoImage allows to analyze “numerically recorded” plankton samples, that is, by using digital images gathered with specialized devices such as the FlowCAM, or the FastCAM (see report 3). A machine learning approach allows to automatically classify the digitized particles into various taxonomic groups. Once this is done, global statistics are calculated on each sample, including the number of particles, the biomass, and the size spectrum per taxonomic group. Two major changes are introduced in the... |
| Tipo: Text |
Palavras-chave: Phytoplancton; REPHY; Analyse d'image; Classification supervisée; Dénombrement de cellules; Apprentissage actif; Manche; Atlantique.; Phytoplankton; REPHY; Image analysis; Machine learning; Cells enumeration; Active learning; The Channel; Atlantic Ocean. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00389/49990/50578.pdf |
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| Registros recuperados: 126 | |
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