Artificially evolved functional shell morphology of burrowing bivalves

DEFF Research Database (Denmark)

Germann, D. P.; Schatz, W.; Hotz, Peter Eggenberger

2014-01-01

dimensional (3D) objects, the first ever artificial evolution of a physical bivalve shell was performed. The result was a vertically flattened shell occupying only the top sediment layers. Insufficient control of the sediment was the major limitation of the setup and restricted the significance of the results......, there are almost no studies experimentally testing their dynamic properties. To investigate the functional morphology of the bivalve shell, we employed a synthetic methodology and built an experimental setup to simulate the burrowing process. Using an evolutionary algorithm and a printer that prints three...

Veda-scope: More comfortable than the bivalve speculum and cytologically equivalent.

Science.gov (United States)

Longmore, Peter G

2004-04-01

The aim of the present study was to confirm that the Veda-scope is equivalent to the bivalve speculum in the collection of endocervical cells, as confirmation of adequate cervical sampling for Pap smear testing. The study also aimed to assess the comfort level of the Veda-scope compared to the traditional bivalve speculum and the patient preference of the Veda-scope compared to the bivalve speculum. Multicentre, randomised, controlled crossover, cytologist blinded study. The total number of subjects enrolled in the study were 250. The number of evaluable subjects were 210. In primary efficacy analysis, no significant difference was seen between the presence or absence of endocervical cells in the smears using either the Veda-scope or the bivalve speculum. There was a high concordance level between the diagnosis assigned to each specimen of a paired sample, the diagnosis agreeing in 97.6% cases. The primary reason given by many women for avoidance of regular Pap smear examinations is the discomfort or pain experienced with sample collection with the bivalve speculum. In the present study, 92% of subjects indicated a preference for the Veda-scope for Pap smear collection, while only 8.4% preferred the bivalve speculum. Subject preference was also assessed with respect to how the subject rated the comfort level of her previous Pap smear. In subjects who rated their previous Pap smear as very comfortable or comfortable, 86% expressed a preference for the Veda-scope. This rose to 93% in subjects who rated their previous Pap smear as only tolerable. The results of the present study show that Pap smear collections with the Veda-scope are of equal quality to those collected with the bivalve speculum, with an equivalent diagnostic outcome. A very strong preference for the Veda-scope was shown by the women enrolled in the present study based on the comfort levels experienced with the two devices.

First evidence of immunomodulation in bivalves under seawater acidification and increased temperature.

Directory of Open Access Journals (Sweden)

Valerio Matozzo

Full Text Available Water acidification, temperature increases and changes in seawater salinity are predicted to occur in the near future. In such a global climate change (GCC scenario, there is growing concern for the health status of both wild and farmed organisms. Bivalve molluscs, an important component of coastal marine ecosystems, are at risk. At the immunological level, the ability of an organism to maintain its immunosurveillance unaltered under adverse environmental conditions may enhance its survival capability. To our knowledge, only a few studies have investigated the effects of changing environmental parameters (as predicted in a GCC scenario on the immune responses of bivalves. In the present study, the effects of both decreased pH values and increased temperature on the important immune parameters of two bivalve species were evaluated for the first time. The clam Chamelea gallina and the mussel Mytilus galloprovincialis, widespread along the coast of the Northwestern Adriatic Sea, were chosen as model organisms. Bivalves were exposed for 7 days to three pH values (8.1, 7.7 and 7.4 at two temperatures (22 and 28°C. Three independent experiments were carried out at salinities of 28, 34 and 40 PSU. The total haemocyte count, Neutral Red uptake, haemolymph lysozyme activity and total protein levels were measured. The results obtained demonstrated that tested experimental conditions affected significantly most of the immune parameters measured in bivalves, even if the variation pattern of haemocyte responses was not always linear. Between the two species, C. gallina appeared more vulnerable to changing pH and temperature than M. galloprovincialis. Overall, this study demonstrated that climate changes can strongly affect haemocyte functionality in bivalves. However, further studies are needed to clarify better the mechanisms of action of changing environmental parameters, both individually and in combination, on bivalve haemocytes.

Bivalve aquaculture-environment interactions in the context of climate change.

Science.gov (United States)

Filgueira, Ramón; Guyondet, Thomas; Comeau, Luc A; Tremblay, Réjean

2016-12-01

Coastal embayments are at risk of impacts by climate change drivers such as ocean warming, sea level rise and alteration in precipitation regimes. The response of the ecosystem to these drivers is highly dependent on their magnitude of change, but also on physical characteristics such as bay morphology and river discharge, which play key roles in water residence time and hence estuarine functioning. These considerations are especially relevant for bivalve aquaculture sites, where the cultured biomass can alter ecosystem dynamics. The combination of climate change, physical and aquaculture drivers can result in synergistic/antagonistic and nonlinear processes. A spatially explicit model was constructed to explore effects of the physical environment (bay geomorphic type, freshwater inputs), climate change drivers (sea level, temperature, precipitation) and aquaculture (bivalve species, stock) on ecosystem functioning. A factorial design led to 336 scenarios (48 hydrodynamic × 7 management). Model outcomes suggest that the physical environment controls estuarine functioning given its influence on primary productivity (bottom-up control dominated by riverine nutrients) and horizontal advection with the open ocean (dominated by bay geomorphic type). The intensity of bivalve aquaculture ultimately determines the bivalve-phytoplankton trophic interaction, which can range from a bottom-up control triggered by ammonia excretion to a top-down control via feeding. Results also suggest that temperature is the strongest climate change driver due to its influence on the metabolism of poikilothermic organisms (e.g. zooplankton and bivalves), which ultimately causes a concomitant increase of top-down pressure on phytoplankton. Given the different thermal tolerance of cultured species, temperature is also critical to sort winners from losers, benefiting Crassostrea virginica over Mytilus edulis under the specific conditions tested in this numerical exercise. In general, it is

The isotopic biosignatures of photo- vs. thiotrophic bivalves: are they preserved in fossil shells?

Science.gov (United States)

Dreier, A; Loh, W; Blumenberg, M; Thiel, V; Hause-Reitner, D; Hoppert, M

2014-09-01

Symbiont-bearing and non-symbiotic marine bivalves were used as model organisms to establish biosignatures for the detection of distinctive symbioses in ancient bivalves. For this purpose, the isotopic composition of lipids (δ13C) and bulk organic shell matrix (δ13C, δ34S, δ15N) from shells of several thiotrophic, phototrophic, or non-symbiotic bivalves were compared (phototrophic: Fragum fragum, Fragum unedo, Tridacna maxima; thiotrophic: Codakia tigerina, Fimbria fimbriata, Anodontia sp.; non-symbiotic: Tapes dorsatus, Vasticardium vertebratum, Scutarcopagia sp.). ∆13C values of bulk organic shell matrices, most likely representing mainly original shell protein/chitin biomass, were depleted in thio- and phototrophic bivalves compared to non-symbiotic bivalves. As the bulk organic shell matrix also showed a major depletion of δ15N (down to -2.2 ‰) for thiotrophic bivalves, combined δ13C and δ15N values are useful to differentiate between thio-, phototrophic, and non-symbiotic lifestyles. However, the use of these isotopic signatures for the study of ancient bivalves is limited by the preservation of the bulk organic shell matrix in fossils. Substantial alteration was clearly shown by detailed microscopic analyses of fossil (late Pleistocene) T. maxima and Trachycardium lacunosum shell, demonstrating a severe loss of quantity and quality of bulk organic shell matrix with time. Likewise, the composition and δ13C-values of lipids from empty shells indicated that a large part of these compounds derived from prokaryotic decomposers. The use of lipids from ancient shells for the reconstruction of the bivalve's life style therefore appears to be restricted. © 2014 John Wiley & Sons Ltd.

Trace Fossil Evidence of Trematode-Bivalve Parasite-Host Interactions in Deep Time.

Science.gov (United States)

Huntley, John Warren; De Baets, Kenneth

2015-01-01

Parasitism is one of the most pervasive phenomena amongst modern eukaryotic life and yet, relative to other biotic interactions, almost nothing is known about its history in deep time. Digenean trematodes (Platyhelminthes) are complex life cycle parasites, which have practically no body fossil record, but induce the growth of characteristic malformations in the shells of their bivalve hosts. These malformations are readily preserved in the fossil record, but, until recently, have largely been overlooked by students of the fossil record. In this review, we present the various malformations induced by trematodes in bivalves, evaluate their distribution through deep time in the phylogenetic and ecological contexts of their bivalve hosts and explore how various taphonomic processes have likely biased our understanding of trematodes in deep time. Trematodes are known to negatively affect their bivalve hosts in a number of ways including castration, modifying growth rates, causing immobilization and, in some cases, altering host behaviour making the host more susceptible to their own predators. Digeneans are expected to be significant agents of natural selection. To that end, we discuss how bivalves may have adapted to their parasites via heterochrony and suggest a practical methodology for testing such hypotheses in deep time. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Bivalve Production Chain in Santa Catarina, Brazil, and its Management and Operational Limitations

OpenAIRE

Gallon, Alessandra Vasconcelos; Universidade Federal do Ceará (UFC); Nascimento, Cristiano; Universidade Federal do Paraná - UFPR; Pfitscher, Elisete Dahmer; Universidade Federal de Santa Catarina

2011-01-01

Bivalve farming (mussels and oysters), a major component in the socio-economic development of the state of Santa Catarina, Brazil, combines the activities of public and private agencies in fish farming. Current analysis deals with the management and the operational limitations of the local bivalve production chain. Current exploratory research, undertaken by direct observations and the literature on the subject, employs data quality. Results show that the bivalve production chain, comprising ...

Predation and habitat modification synergistically interact to control bivalve recruitment on intertidal mudflats

NARCIS (Netherlands)

van der Heide, T.; Tielens, E.; van der Zee, E.M.; Weerman, E.J.; Holthuijsen, S.; Eriksson, B.K.; Piersma, T.; van de Koppel, J.; Olff, H.

2014-01-01

Bivalves are key components of coastal ecosystems because they link pelagic and benthic food webs, and shape the landscape through habitat modification. Nevertheless, many bivalve stocks have dramatically declined, and recruitment failure due to (anthropogenically-) increased predation by

Predation and habitat modification synergistically interact to control bivalve recruitment on intertidal mudflats

NARCIS (Netherlands)

van der Heide, Tjisse; Tielens, Elske; van der Zee, Els; Weerman, Ellen J.; Holthuijsen, Sander; Eriksson, Britas Klemens; Piersma, Theun; van de Koppel, Johan; Olff, Han

Bivalves are key components of coastal ecosystems because they link pelagic and benthic food webs, and shape the landscape through habitat modification. Nevertheless, many bivalve stocks have dramatically declined, and recruitment failure due to (anthropogenically-) increased predation by

Short-term fluctuations in bivalve larvae compared with some environmental factors in a coastal lagoon (South Portugal

Directory of Open Access Journals (Sweden)

Luis M.Z. Chícaro

2000-12-01

Full Text Available In this study, short-term fluctuations in bivalve larvae were compared with some triggering factors for a period of sixteen months. Data on the abundance of planktonic larvae, collected two to three times a week were related to water temperature, salinity, wind velocity, tidal amplitude and chlorophyll a. Higher densities of planktonic bivalve larvae were caught between May and August, but intense fluctuations in abundance were observed. Planktonic bivalve larvae of eighteen taxa were identified. Larvae of Mytilus galloprovincialis, Cerastoderma edule, Ruditapes decussates and Venerupis spp. were the most abundant. The seasonal fluctuations of bivalve abundance seem to be controlled by temperature, the major factor in the timing of the reproduction of bivalves. Nevertheless, advection may be also a key factor during the planktonic life of bivalve species in coastal systems, such as the Ria Formosa.

Bivalves: From individual to population modelling

NARCIS (Netherlands)

Saraiva, S.; van der Meer, J.; Kooijman, S.A.L.M.

2014-01-01

An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg

Development of human impact on suspension-feeding bivalves in coastal soft-bottom ecosystems

NARCIS (Netherlands)

Wolff, Wim J.; Dame, RF; Olenin, S

2005-01-01

Suspension-feeding bivalves often may occur in large concentrations ('beds') on tidal flats. This makes them attractive for human consumers and the archaeological record shows collection of bivalves by coastal populations already tens of thousands of years ago. In modem time human interference with

Histological techniques for marine bivalve mollusks and crustaceans, 2nd edition

OpenAIRE

Howard, Dorothy W.; Lewis, Earl J.; Keller, B. Jane; Smith, Cecelia S.

2004-01-01

Investigators at the Cooperative Oxford Laboratory (COL) diagnose and study crustaceans, mollusks, finfish, and a variety of other marine and estuarine invertebrates to assess animal health. This edition updates the Histological Techniques for Marine Bivalve Mollusks manual by Howard and Smith (1983) with additional chapters on molluscan and crustacean techniques. The new edition is intended to serve as a guide for histological processing of shellfish, principally bivalve mollusks and crustac...

Nursery function of coastal temperate benthic habitats: New insight from the bivalve recruitment perspective

Science.gov (United States)

Barbier, Pierrick; Meziane, Tarik; Forêt, Martin; Tremblay, Réjean; Robert, René; Olivier, Frédéric

2017-03-01

Marine habitat function has been typically investigated in terms of biogeochemical regulation but rarely in terms of population renewal, which is mainly controlled by recruitment dynamics. The recruitment phase is crucial for organisms with a bentho-pelagic life cycle, such as bivalves, and it regulates the population renewal success. This study provides new insight on the role of temperate benthic habitats on bivalve recruitment, as a function of nursery areas. Six dominant benthic habitats of the Chausey archipelago (Normandy, France) were studied. In each habitat, bivalve recruit assemblages were described at the end of two reproductive seasons. Furthermore, Ostrea edulis juveniles were immerged on each habitat during two months to compare growth performances and feeding status, estimated by fatty acid composition. Recruit assemblages differ from each habitat according to sediment grain-size composition and bathymetrical levels. Subtidal habitats, and especially Crepidula fornicata banks and Glycymeris glycymeris coarse sands, supported the highest species abundance and richness of recruits. All O. edulis juveniles fed on the same trophic resources but digestive glands of juveniles from C. fornicata banks were more concentrated in total fatty acids than those from subtidal G. glycymeris coarse sands and maerl banks. Our results depict the key role of subtidal and structured habitats, composed of ecosystem engineers, in enhancing bivalve recruitment and extending the bivalve population renewal. This study suggests that the crucial role of these habitats as bivalve nurseries must be integrated in management perspectives. 2-column fitting image. 1-column fitting image.

A Darriwilian (Middle Ordovician bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia

Directory of Open Access Journals (Sweden)

Kristian G. Jakobsen

2016-12-01

Full Text Available A bivalve-dominated molluscan fauna is described from the Darriwilian (Middle Ordovician Stairway Sandstone, Amadeus Basin, central Australia. The fauna comprises 16 species of bivalves and rostroconchs plus six gastropod species which are treated under open nomenclature. Two new bivalves, Sthenodonta paenesymmetrica sp. nov. and Modiolopsis pojetai sp. nov., are described. The relatively low-diverse molluscan fauna constitutes around 62% of the total benthic macrofauna. Approximately 75% of the molluscs comprise bivalves, especially nuculoids, which were biogeographically restricted to low latitudes during the Ordovician. The molluscan assemblage displays a very high degree of endemism at species level, though the bivalve Sthenodonta eastii also occurs in the Georgina Basin farther to the northeast. This indicates a possible marine connective seaway between the Georgina and Amadeus basins during the Darriwilian. Nuculites, Cyrtodonta, and Modiolopsis are cosmopolitan and previously reported from North China, Avalonia, and Southern Gondwana.

Dioxin-like chemicals in bivalves and sediment collected from around Australia

Energy Technology Data Exchange (ETDEWEB)

Mueller, J.F.; Muller, R.; Goudkamp, K. [EnTox, The University of Queensland, Brisbane (AU)] (and others)

2004-09-15

The aquatic environment is a significant sink for persistent organic pollutants including dioxin-like chemicals. Besides continuous investigations into sources of higher chlorinated PCDD that have initially been found in soils, and later in dugong and sediments little is known about the levels of dioxin-like chemicals in Australia's aquatic environment. In 2002 the National Dioxin Program (NDP) was commissioned by the Department of Environment and Heritage, Australia. One focus of the NDP was to evaluate background levels of dioxin-like chemicals in Australia's environment. One component of the 'Environmental Levels' project aimed to identify dioxinlike chemicals in the aquatic environment including bivalves collected in both marine, estuarine and freshwater systems. Here we report results from the NDP aquatic study with a particular emphasis on the levels of dioxin-like chemicals in bivalves and sediments respectively in areas from where the bivalves were collected.

Bioaccumulation of 210Po in common gastropod and bivalve species from the northern Gulf.

Science.gov (United States)

Uddin, S; Bebhehani, M

2014-06-01

This study sets the baseline for the concentration of the natural-series radionuclide polonium-210 in two species of gastropods and four species of bivalves that are common to the Northern Arabian/Persian Gulf. (210)Po is primarily absorbed from water and via ingestion of detrital material by gastropoda and bivalves. This concentrated (210)Po can then be passed along to the next trophic level of the marine food web. The lowest (210)Po concentration was measured in the gastropod Stomatella auricular (10.36-12.39Bq kg(-1)dry) and the highest in the bivalve Marica marmorata (193.51-215.60Bq kg(-1)dry). The measured concentration factor for these molluscs in the northern Gulf varied between 4.8 and 115×10(3), values very similar to the IAEA recommended value for bivalves and gastropods of 2×10(4). Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of dietary polyunsaturated fatty acids on reproductive output and larval growth of bivalves

NARCIS (Netherlands)

Hendriks, I.E.; Van Duren, L.A.; Herman, P.M.J.

2003-01-01

The pre-spawning condition of adult bivalves is influenced by quantity and quality of available food. For bivalves, the essential polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) 20:5(n-3) and docosahexaenoic acid (DHA) 22:6(n-3) are presumed to determine the nutritional value of

Travel report Mauritania bivalve Molluscs october 2008

NARCIS (Netherlands)

Poelman, M.

2008-01-01

During the last four years Mauritania has been working on the completion of a Food Safety Program of Bivalve Mollusks, in order to obtain an export approval by the Europe Union. During the preparations for an inspection by the FVO (Food and Veterinary Office) no fisheries or production activities

Linking changes in subcellular cadmium distribution to growth and mortality rates in transplanted freshwater bivalves (Pyganodon grandis)

International Nuclear Information System (INIS)

Perceval, Olivier; Couillard, Yves; Pinel-Alloul, Bernadette; Campbell, Peter G.C.

2006-01-01

Relationships between Cd accumulation and subcellular distribution, and growth and mortality rates were examined in the freshwater bivalve Pyganodon grandis in a transplant experiment. Organisms were transferred from a clean lacustrine site to four lakes situated along a Cd concentration gradient in the mining region of Rouyn-Noranda. The bivalves were maintained in open enclosures placed in the bottom sediments of the littoral zone of all five lakes for 400 days. At the end of the experiment, metallothionein (MT) was measured in the bivalve gills with a Hg-saturation assay and Cd partitioning among the various cytosolic protein pools was determined by size-exclusion chromatography. Marked differences were observed among the five sites: the range in calculated free-cadmium ion concentrations in water overlying the sediments was 35-fold whereas Cd concentrations in the gill cytosol of the transplanted bivalves varied three-fold. In the transplanted bivalves, the distribution of gill Cd among the various cytosolic complexes also varied significantly among sites. For bivalves transplanted to the three most contaminated sites, Cd concentrations in the high molecular weight pool (HMW > 25 kDa) were significantly higher than the baseline levels determined from bivalves caged at the reference site; a similar trend was seen for Cd concentrations in the metallothionein pool (Cd-MT). For bivalves transferred to two of the high contamination sites, proportionately less of the gill cytosolic Cd was sequestered (i.e. detoxified) by MT-like proteins. Reductions in survival were also observed at these two sites, and these elevated mortalities, in turn, were consistent with the absence of indigenous bivalve populations at these sites. This result is compatible with our recent work on P. grandis populations living in lakes of the Rouyn-Noranda area, in which we demonstrated that excessive accumulation of Cd in the HMW pool of the gill cytosol of the individual mollusks could be

Bivalve aquaculture transfers in Atlantic Europe. Part A: Transfer activities and legal framework

DEFF Research Database (Denmark)

Muehlbauer, F.; Fraser, D.; Brenner, M.

2014-01-01

environment and address economic considerations remains unanswered. This study provides the first overview of bivalve transfer activities for aquaculture purposes along the European Atlantic coast. Existing international and EU legislation is described, and potential weaknesses in the existing legislative......Intentional transfers of numerous bivalve species have had a long tradition and are commonly conducted along the European Atlantic coast. However numerous studies have concluded that intentional transfer of species for aquaculture purposes is one of the most principal vectors for the introduction...... frameworks are discussed. Recommendations for the development of integrated risk assessment methods are given. These may help to minimize the intrinsic threats of transfer activities in marine environments. The resulting impacts and effects of transfer activities of bivalves for aquaculture purpose...

Morphometric Studies on Anodonta Anatine Bivalve Population from the Dognecea Lake

Directory of Open Access Journals (Sweden)

Marian Bura

2011-10-01

Full Text Available In the Dognecea Lake, near town Bocsa in Caras-Severin county a strong bivalve population has been discovered from the duck mussel specie (Anodonta anatina. Harvested individuals were transported to the Aquaculture laboratory where measurements and correct identification was made. This specie is considered endangered but in Banat area, especially in the Dognecea Lake it is well represented, having an ecological importance, but the bivalve can have an economical importance too, due to the high percentage of edible part of 56.5%.

Proteomic Profiling of Cytosolic Glutathione Transferases from Three Bivalve Species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea

Directory of Open Access Journals (Sweden)

José Carlos Martins

2014-01-01

Full Text Available Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs, in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

The use of bivalves as rapid, real-time indicators of aquatic pollution

International Nuclear Information System (INIS)

Markich, S.J.

1995-01-01

The ability of bivalves to filter large volumes of water on a daily basis, combined with the relatively high permeability of their cell membranes, make them valuable organisms to use in the contemporary detection of pollution. Bivalves are well known to respond to chemical contaminants by isolating their soft tissues from the aquatic medium by valve closure. The sensory acuity (via specialized sensory regions including the osphradium) and associated repertoire of this behavioral response can be employed to assess subtle effects exerted by chemical contaminants, such as complex effluents, that may ultimately influence the survival of these organisms. As hazard assessment tools, behavioral studies reflect sublethal toxicity and often yield a highly sensitive estimate of the lowest observable effect concentration (LOEC). Moreover, valve movement behavior has been identified as one of the more sensitive biological early warning measures to a variety of aquatic contaminants, in comparison with those used in other aquatic animal phyla. Therefore, the valve movement behavior of both freshwater (Hyridella depressa, Velesunio angasi and V. ambiguus) and marine (Mytilus edulis) bivalves was continuously monitored, using an on-line computer based data acquisition system, during exposure to either trace metals (e.g. Cu, Cd, Mn and U) or complex effluents (ie treated sewage effluent and acid leachate derived from contaminated Sydney Harbour sediments), in the context of using the valve movement behavior of the bivalve species to indicate the biological significance of exposure to the above-mentioned pollutants. The results indicate that several components of the valve movement behavior of each bivalve provide quantifiable and ecologically interpretable sub-lethal endpoints for the rapid and sensitive evaluation of waters containing either complex effluents or elevated levels of trace metals

An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

DEFF Research Database (Denmark)

Filgueira, Ramón; Byron, C.J.; Comeau, L.A.

2015-01-01

, is needed to provide a rigorous assessment of the role of bivalve mariculture in the CO2 cycle. On the other hand, the discussion about the inclusion of shells of cultured bivalves into the carbon trading system should be framed in the context of ecosystem goods and services. Humans culture bivalves......The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densities...... with the aim of producing food, not sequestering CO2 in their shells, therefore the main ecosystem good provided by bivalve aquaculture is meat production, and shells should be considered as by-products of this human activity. This reasoning is key to split the CO2 released due to respiration between meat...

Lower Oligocene bivalves of Ramanian Stage from Kachchh ...

Indian Academy of Sciences (India)

Sehe area of western Kachchh considered their. Bed Nos. 4 and 5 as .... with very thin population. The Bermoti stream ...... Recent; Indo–Pacific. Subgenus: .... Type species: Cardium discors Lamarck' 1805; T. Eocene–Miocene; Europe–Asia ..... Shuto Tsugio 1971 Neogene Bivalves from Panay Island, the. Philippines.

76 FR 65200 - Risk Assessment on Norovirus in Bivalve Molluscan Shellfish: Request for Comments and for...

Science.gov (United States)

2011-10-20

... transmission of norovirus from infected or ill food workers in food manufacturing or retail establishments to... Molluscan Shellfish Contamination Levels During Food Preparation and Bivalve Molluscan Shellfish Consumption... and other factors influencing bivalve molluscan shellfish contamination levels during food preparation...

Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses

Science.gov (United States)

Wang, Sikai; Jin, Binsong; Qin, Haiming; Sheng, Qiang; Wu, Jihua

2015-01-01

Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI) and fatty acid (FA) techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25%) to particular organic matter (POM) in summer, while diatoms contributed the most (12.68 ± 1.17%) during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44%) and winter (25.51 ± 0.59%), and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter) at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems. PMID:26261984

Environmentally applications of invasive bivalves for water and wastewater decontamination.

Science.gov (United States)

Gomes, João; Matos, Ana; Quinta-Ferreira, Rosa M; Martins, Rui C

2018-07-15

The environmental and economic impact of invasive bivalve species implies the development of suitable pest management strategies. Chemical control is the most usual approach. However, the production of toxic intermediates as well as the unavoidable impact over non target biota is of special concern. Another approach consists on the physical removal of the animals from the invaded sites. The high biofiltration and bioaccumulation capacity of such animals make them interesting for the removal of contaminants from water and wastewater. In this context, environmental applications can be given for these pests encompassing nutrients removal for the recovery of eutrophic sites, water disinfection, organic and metal contaminants abatement. These approaches may be integrated with pest management where the physical removed animals from the invaded spots could be used for assembling biofilter for water and wastewater decontamination. However, some drawbacks must be addressed before proposing such alternative. In fact, the further spreading of the bivalves into non-invaded sites must be avoided. Moreover, some operational questions must be addressed such as the fate of contaminated animals after biofiltration. Bearing in mind the interesting results already available in this subject, this paper aims to critically overview literature regarding the environmental applications of invasive bivalves. Copyright © 2018 Elsevier B.V. All rights reserved.

Spermatozoan ultrastructure in the trigonioid bivalve Neotrigonia margaritacea Lamarck (Mollusca): Comparison with other bivalves, especially Trigonioida and Unionoida

Science.gov (United States)

Healy, J. M.

1996-06-01

Spermatozoa of the trigonioid bivalve Neotrigonia margaritacea (Lamarck) (Trigoniidae, Trigonioida) are examined ultrastructurally. A cluster of discoidal, proacrosomal vesicles (between 9 to 15 in number) constitutes the acrosomal complex at the nuclear apex. The nucleus is short (2.4 2.6 μm long, maximum diameter 2.2 μm), blunt-conical in shape, and exhibits irregular lacunae within its contents. Five or sometimes four round mitochondria are impressed into shallow depressions in the base of the nucleus as is a discrete centriolar fossa. The mitochondria surround two orthogonally arranged centrioles to form, collectively, the midpiece region. The distal centriole, anchored by nine satellite fibres to the plasma membrane, acts as a basal body to the sperm flagellum. The presence of numerous proacrosomal vesicles instead of a single, conical acrosomal vesicle sets Neotrigonia (and the Trigonioida) apart from other bivalves, with the exception of the Unionoida which are also known to exhibit this multivesicular condition. Spermatozoa of N. margaritacea are very similar to those of the related species Neotrigonia bednalli (Verco) with the exception that the proacrosomal vesicles of N. margaritacea are noticeably larger than those of N. bednalli.

First records of Freshwater Bivalves of Ilha Grande National Park, Paraná, Brazil

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Flávio Henrique Ragonha

2014-03-01

Full Text Available The Ilha Grande National Park, Paraná, Brazil, is located in the Upper Paraná River and has characteristics typical of a floodplains. This protected area includes lagoons connected and disconnected to the Paraná River, although the latter also connect during periods of high water level, thus composing a heterogeneous group of lacustrine environments. The enormous potential the flora and fauna diversities are still little known to the region, as can be seen through benthic invertebrates, inclunding bivalves mollusks. The granulometric composition of these floodplain lagoons was formed mainly by mud and very fine sand. Furthermore, organic matter composition was predominantly of fine particulate. The other abiotic factors differed from lagoons located within the island of the park to those located in the left margin of Paraná River. The results demonstrated the importance of abiotic factors such as the physical composition of granulometric texture, organic matter and macrophyte banks, to the establishment of bivalves in these floodplain lagoons. We recorded bivalves of Pisidium (native, Diplodon (native, and Corbicula (invasive. The highest values of Diplodon sp. density were observed at São João/C lake, for Pisidium sterkianum (Pilsbry, 1897 at São João/M lake, and to Jatobá/C lagoon with high density of invasive species Corbicula fluminea (Müller, 1774. This study to obtain conduct the first records of freshwater bivalves in floodplains lagoon in the Ilha Grande National Park, and provides contributions to better understanding the ecology of these mollusks. The recording of native species in the region of Upper Paraná River floodplain after a lomg period without new records, demonstrated the importance of protecting the lagoons of the Ilha Grande National Park as they can be a possible refuge to some species of native freshwater bivalves.

Geochemical aspects of Meretrix casta (bivalve) shells of Vellar ...

African Journals Online (AJOL)

SAM

2014-05-14

May 14, 2014 ... The bivalve mollusk, Meretrix casta shells are abundant in the Vellar estuary along the East .... the Shervarayan hills of Salem District in Tamil Nadu, India. .... coast of Peninsular Malaysia and its potential as biomaterial for use.

Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

International Nuclear Information System (INIS)

Praveen Kumar, M.K.; Shyama, S.K.; Sonaye, B.S.; Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A.; Chaubey, R.C.

2014-01-01

Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

Energy Technology Data Exchange (ETDEWEB)

Praveen Kumar, M.K., E-mail: here.praveen@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Shyama, S.K., E-mail: skshyama@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Sonaye, B.S. [Department of Radiation Oncology, Goa Medical College, Goa (India); Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A. [Department of Zoology, Goa University, Goa 403206 (India); Chaubey, R.C. [Radiation Biology and Health Science Division, Bhabha Atomic Research Centre, Mumbai (India)

2014-05-01

Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

The miRNA biogenesis in marine bivalves

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Umberto Rosani

2016-03-01

Full Text Available Small non-coding RNAs include powerful regulators of gene expression, transposon mobility and virus activity. Among the various categories, mature microRNAs (miRNAs guide the translational repression and decay of several targeted mRNAs. The biogenesis of miRNAs depends on few gene products, essentially conserved from basal to higher metazoans, whose protein domains allow specific interactions with dsRNA. Here, we report the identification of key genes responsible of the miRNA biogenesis in 32 bivalves, with particular attention to the aquaculture species Mytilus galloprovincialis and Crassostrea gigas. In detail, we have identified and phylogenetically compared eight evolutionary conserved proteins: DROSHA, DGCR8, EXP5, RAN, DICER TARBP2, AGO and PIWI. In mussels, we recognized several other proteins participating in the miRNA biogenesis or in the subsequent RNA silencing. According to digital expression analysis, these genes display low and not inducible expression levels in adult mussels and oysters whereas they are considerably expressed during development. As miRNAs play an important role also in the antiviral responses, knowledge on their production and regulative effects can shed light on essential molecular processes and provide new hints for disease prevention in bivalves.

An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

Science.gov (United States)

Duperron, S.; Gaudron, S. M.; Rodrigues, C. F.; Cunha, M. R.; Decker, C.; Olu, K.

2013-05-01

Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae). Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

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S. Duperron

2013-05-01

Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae. Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay.

Science.gov (United States)

Praveen Kumar, M K; Shyama, S K; Sonaye, B S; Naik, U Roshini; Kadam, S B; Bipin, P D; D'costa, A; Chaubey, R C

2014-05-01

Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of 'Comet assay' for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in both bivalve species. This showed a dose-dependent increase of genetic damage induced in bivalves by EMS as well as gamma radiation. Further, the highest DNA damage was observed at 24h. The damage gradually decreased with time, i.e. was smaller at 48 and 72 h than at 24h post irradiation in both species of bivalves. This may indicate repair of the damaged DNA and/or loss of heavily damaged cells as the post irradiation time advanced. The present study

Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

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George G Waldbusser

Full Text Available Ocean acidification (OA is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4 with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material

Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

Science.gov (United States)

Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

2015-01-01

Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by

Anodontites trapesialis (LAMARCK, 1819: a bivalve parasite of freshwater fishes / Anodontites trapesialis (LAMARCK, 1819: um bivalve parasito de peixes de água doce

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Ângela Teresa Silva-Souza

2008-08-01

Full Text Available The bivalve mollusk Anodontites trapesialis has been indicated as an alternative source for aquaculture because it is considered a food of good nutritional value with a protein content close to that of fish. Its shells can be utilized as fertilizer and mixed to the food of domestic animals, and the nacre can be used to manufacture buttons and crafts. However, the larvae of A. trapesialis, which are the lasidium type, are obligatory parasites of freshwater fishes, and the introduction of this bivalve in fish farm tanks have caused trouble and losses for producers. Nothing is known, however, about their development in these environments. On the other hand, it should be pointed out that A. trapesialis is on Brazil’s list of species threatened with extinction. This article provides a compilation of information present in the literature, offering a detailed review, with the aim of presenting a general panorama of what is known about Anodontites trapesialis and its larval parasitism of fishes.O molusco bivalve, Anodontites trapesialis, tem sido indicado como fonte alternativa para a aqüicultura, por ser considerado um alimento de bom valor nutricional com um conteúdo protéico próximo ao do pescado. Suas conchas podem ser utilizadas como fertilizantes calcáreos e ser agregadas a alimentos de animais domésticos e o nácar pode ser utilizado para fabricar botões e artesanatos. No entanto, as larvas de A. trapesialis, que são do tipo lasidium, são parasitas obrigatórias de peixes de água doce e a introdução desse bivalve em tanques de piscicultura tem causado transtornos e prejuízos aos produtores. Nada se conhece, porém, sobre o seu desenvolvimento nesses ambientes. Por outro lado, ressalta-se que A. trapesialis consta da lista brasileira de espécies ameaçadas de extinção. No presente artigo são compiladas as informações presentes na literatura, em uma revisão detalhada, com o objetivo de apresentar o panorama geral do

Modiolarca lateralis (Pteryomorphia: Mytilidae: bivalve associated to six species of ascidians from Bocas del Toro, Panama

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Juan I Cañete

2013-11-01

Full Text Available We describe the presence of the bivalve Modiolarca lateralis (Say, 1822 in six tropical ascidians Ascidia curvata, A. sydneiensis, A. panamensis, A. interrupta, Herdmania pallida and Polycarpa spongiabilis collected at depths of 1-3 m on coral reefs, mangrove roots and dock supports in Almirante Bay, Bocas del Toro, Panama (9°18'N, 82°13'W during June-July 2011. Bivalve prevalence varied between 9-30% across species, but was mainly associated with A. panamensis, P. spongiabilis and A. interrupta. Prevalence seems to be influenced by tunic thickness rather than by the ascidian size. Bivalves varied in size (0.6-11 mm shell length, with the smallest individual found in A. sydneiensis. There were only one or two bivalves per ascidians, although a maximum of 18 was found in one A. panamensis. M. lateralis seems to behave similarly to its temperate counterparts: it has a variety of hosts, occurs mainly in the anterior region of the ascidians, and has a variable abundance per host.

Shell growth and environmental control of methanophyllic Thyasirid bivalves from Svalbard cold seeps

Science.gov (United States)

Carroll, Michael; Åström, Emmelie; Ambrose, William; Locke, William; Oliver, Graham; Hong, Wei-Li; Carroll, JoLynn

2016-04-01

The analysis of molluscan shell material (sclerochronology) can provide information about an organism's age, growth history, and environmental conditions during its lifetime. Bivalve molluscs are common members of hydrothermal vents and methane cold seeps communities where, supported by chemosynthetic symbionts, they can reach high density and biomass. But little is known about methane-associated bivalve populations inhabiting high-Arctic cold seeps, and sclerochronological analysis of methane-influenced bivalves is rare. We measured growth rates and elemental and isotopic shell signatures in a newly discovered species of bivalve (Thyasiridae) from cold seeps at 350-390m depth southwest of Svalbard. First discovered in 2014, recently described shells of Thyasira capitanea sp.nov. were found at 2 independent seep systems in Storfjordrenna. Mean shell carbon isotopic ratios from inorganic δ13C (mean = -4.8‰) and organic δ13C (mean = -26.9‰) fractions clearly indicate a methane influenced habitat and food source for these organisms. Shell mineral ratios (Li/Ca, Mg/Ca, Mn/Ca, Fe/Ca, Sr/Ca, Ba/Ca, Pb/Ca) sampled along the axis of growth with laser-ablated ICP-MS exhibit variability through time and between sites, suggesting that concentrations of these elements that may be affected by methane emissions. The mineralogical data also elucidates the internal pattern of shell deposition and growth checks, and combined with the isotopic and growth rate data, enables us to interpret the temporal history of methane release from these locations.

Influence of food on the assimilation of selected metals in tropical bivalves from the New Caledonia lagoon: Qualitative and quantitative aspects

International Nuclear Information System (INIS)

Hedouin, Laetitia; Metian, Marc; Lacoue-Labarthe, Thomas; Fichez, Renaud; Teyssie, Jean-Louis; Bustamante, Paco; Warnau, Michel

2010-01-01

The present study aimed at examining the influence of food quality and quantity on the assimilation efficiency (AE) of metals in two abundant bivalves in the New Caledonia lagoon, the oyster Isognomon isognomon and the clam Gafrarium tumidum. Bivalves were exposed via their food to the radiotracers of three metals of concern in New Caledonia ( 54 Mn, 57 Co and 65 Zn) under different feeding conditions (phytoplankton species, cell density, and cell-associated metal concentration). When bivalves were fed Heterocapsa triquetra, Emiliania huxleyi and Isochrysis galbana, AE of Mn, Co and Zn was strongly influenced by the phytoplankton species and by the metal considered. In contrast, when fed one given phytoplankton species previously exposed to different concentrations of Co, phytoplankton-associated Co load had no influence on the AE and on the retention time of the metal in both bivalves. Metals ingested with I. galbana displayed generally the highest AE in both bivalve species, except for Mn in clams for which the highest AE was observed for H. triquetra. Influence of food quantity was investigated by exposing bivalves to different cell densities of I. galbana (5 x 10 3 , 10 4 or 5 x 10 4 cell ml -1 ). As for food quality, food quantity was found to influence AE of Mn, Co and Zn, the highest AE being observed when bivalves were fed the lowest cell density. Overall, results indicate that the two bivalve species are able to adjust their feeding strategies according to the food conditions prevailing in their environment.

Congener-specific distribution and bioaccumulation of short-chain chlorinated paraffins in sediments and bivalves of the Bohai Sea, China.

Science.gov (United States)

Ma, Xindong; Chen, Chen; Zhang, Haijun; Gao, Yuan; Wang, Zhen; Yao, Ziwei; Chen, Jiping; Chen, Jingwen

2014-02-15

Short-chain chlorinated paraffins (SCCPs) are a new type of persistent organic pollutants that are of great environmental concern because of their wide distribution. In this study, surface sediments and bivalve samples were collected from the coastal area of the Bohai Sea in China. Total SCCP (ΣSCCP) concentrations in surface sediments and bivalves ranged from 97.4 ng g(-1) dry weight (dw) to 1756.7 ng g(-1) dw and 476.4-3269.5 ng g(-1) dw, respectively. C10-CPs and C11-CPs were the predominant homologue groups in all sediments and bivalves. Specific congener composition analysis and correspondence analysis indicated that the local SCCP source mainly came from CP-42 and CP-52 products, and riverine input had an important function. The biota-sediment accumulation factors of ΣSCCPs for bivalves ranged from 1.08 to 1.61, and a significant correlation indicated that the SCCP congener with higher chlorination degree was more likely to be accumulated in bivalves. Copyright © 2014. Published by Elsevier Ltd.

Uncharted waters: Bivalves of midway atoll and integrating mathematics into biology education

Science.gov (United States)

McCully, Kristin M.

To protect and conserve the Earth's biodiversity and ecosystem services, it is important not only to understand and conserve species and ecosystems, but also to instill an understanding and appreciation for biodiversity and ecosystem services in the next generations of both scientists and citizens. Thus, this dissertation combines research into the ecology and identity of large bivalves at Midway Atoll in the Northwestern Hawaiian Islands (NWHI) with research on pedagogical strategies for integrating mathematics into undergraduate biology education. The NWHI is one of the few remaining large, mainly intact, predator-dominated coral reef ecosystems and one of the world's largest marine protected areas. Previous bivalve studies focused on the black-lipped pearl oyster, Pinctada margaritifera, which was heavily harvested in the late 1920s, has not recovered, and is now a candidate species for restoration. First, I combined remote sensing, geographic information systems, SCUBA, and mathematical modeling to quantify the abundance, spatial distributions, and filtration capacity of large epifaunal bivalves at Midway Atoll. These bivalves are most abundant on the forereef outside the atoll, but densities are much lower than reported on other reefs, and Midway's bivalves are unlikely to affect plankton abundance and productivity inside the lagoon. Second, I used molecular techniques and phylogenetic reconstructions to identify pearl oysters (Pinctada) from Midway Atoll as P. maculata , a species not previously reported in Hawaii. As a small morphologically cryptic species, P. maculata may be a native species that has not been collected previously, a native species that has been identified incorrectly as the morphologically similar P. radiata, or it may be a recent introduction or natural range extension from the western Pacific. Finally, I review science education literature integrating mathematics into undergraduate biology curricula, and then present and evaluate a

EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain.

Science.gov (United States)

O'Mahony, Micheál

2018-03-10

Food safety risk assessment in the European Union (EU) recognises consumer illness that arises from marine biotoxins as a risk associated with bivalve mollusc consumption. EU food regulations contain various general food safety obligations, which should contribute significantly to managing this risk. EU food regulations additionally impose various specific obligations on both Food Business Operators and Competent Authorities in order to manage the marine biotoxin food safety risk in the bivalve mollusc food-chain. These have a particular focus on the pre-harvest component of the food-chain. A central component of these specific systems is the requirement for ongoing monitoring of phytoplankton and biotoxin concentrations in water and molluscs, respectively. This monitoring explicitly brings a potential outcome of closing production areas delineated by classification to prohibit the harvest of bivalve molluscs as food from those areas when acceptable biotoxin concentrations are exceeded. This review considers the utility of these systems, at conceptual and practical levels, and explores their contribution to an effective regulatory risk management approach.

SHRIMP (CRANGON-CRANGON L) BROWSING UPON SIPHON TIPS INHIBITS FEEDING AND GROWTH IN THE BIVALVE MACOMA-BALTHICA (L)

NARCIS (Netherlands)

KAMERMANS, P; HUITEMA, HJ

1994-01-01

The influence of siphon browsing on the feeding behaviour and growth of Macoma balthica, a deposit-feeding bivalve, was studied in three manipulative experiments. Browsing was simulated by removing part of the inhalant siphon with scissors, or studied by exposing the bivalves to shrimps (Crangon

Lower Oligocene bivalves of Ramanian Stage from Kachchh, Gujarat, India

Science.gov (United States)

Kachhara, R. P.; Jodhawat, R. L.; Devi, K. Bigyapati

2012-04-01

Marine Oligocene sequences in India outcrop only in western part of Kachchh. Earlier researchers have recognized the Oligocene strata under the Nari Series (Nagappa 1959; Chatterji and Mathur 1966). The Nari Series has a type area in Pakistan. It has two subdivisions - the Lower Nari (Lower Oligocene) and the Upper Nari (Upper Oligocene). It seems that there is no valid proof about the age of the Lower Nari due to lack of proper fauna (Eames 1975), and according to Pascoe (1962), the Upper Nari slightly transgress into Aquitanian (Lower Miocene), therefore, one has to be very cautious. Biswas and Raju (1971) reclassified the Oligocene strata of Kachchh and lithostratigraphically clubbed them as the Maniyara Fort Formation with type section along the Bermoti stream. This Formation has four members. The lower three members correspond to the Ramanian Stage (Lower Oligocene, Biswas 1971, 1973) while the uppermost to the Waiorian Stage (Upper Oligocene, Biswas 1965, 1971, 1973). The Ramanian Stage is characterized by large forams especially Nummulites fichteli, Nummulites fichteli intermedius, Lepidocyclina ( Eulepidina) dialata and Operculina sp. Several ostracods are also known to occur. Megafauna include bivalves, gastropods, echinoids, corals, mammals and reptiles. Concerning bivalves earlier researchers have recorded a few taxa namely Trisidos semitorta (Lamarck), Cubitostrea angulata (J de C Sowerby), Pecten ( Amussiopecten) labadyei d'Archiac and Haime, Periglypta puerpera (Linne') var. aglaurae Brongniart, Ostrea fraasi Mayer Eymer and listed Pecten laevicostatus J de C Sowerby, Callista pseudoumbonella Vredenburg and Clementia papyracea (Gray) from Kachchh as against overall 42 forms from the Nari Series as a whole (Vredenburg 1928). This tempted us to make an attempt to collect bivalve fauna systematically which are occurring prolifically in the Ramanian Stage. In the present work, for this purpose, sections are worked out around Lakhpat (23°50'N; 68°47'E

Seasonal variability in somatic and reproductive investment of the bivalve

NARCIS (Netherlands)

Santos, S.; Cardoso, J.F.M.F.; Carvalho, C.; Luttikhuizen, P.C.; van der Veer, H.W.

2011-01-01

Monthly investment in soma and gonads in the bivalve Scrobicularia plana is described for three populations along its distributional range: Minho estuary, Portugal; Westerschelde estuary, The Netherlands and Buvika estuary, Norway. Seasonal cycles in body mass (BMI), somatic mass (SMI) and

Organisms associated with the sandy-beach bivalve Donax serra ...

African Journals Online (AJOL)

57: 134-136. BROWN, AC. & WEBB, S.c. 1994. Organisms associated \\.,.,ith burrowing whelks of the genus Bullia. S Afr. 1. Zool. 29: 144-151. BROWN, A.C., STENTON-DOZEY, J.~.E. & TRUEMAN, E.R.. 1989. Sandy-beach bivalves and gastropods; a comparison between Donax serra and Ruilia digitalis. Adv. mar. Bioi. 25:.

Otimização do processo de depuração de moluscos bivalves

OpenAIRE

Correia, Maria Helena Oliveira Casimiro

2016-01-01

A contaminação microbiológica de moluscos bivalves constitui uma das principais preocupações inerentes à segurança alimentar desta importante fonte de receitas para a economia portuguesa. Os bivalves capturados ou produzidos em zonas estuarinas ou lagunares devem passar por um processo de depuração, para redução dos níveis de contaminação microbiológica, antes da sua comercialização. Este trabalho teve como principal objetivo o desenvolvimento de sistemas modulares de dep...

Phenology of abundance of bivalve spat and of their epibenthic predators: limited evidence for mismatches after cold winters

NARCIS (Netherlands)

Dekker, R.; Beukema, J.J.

2014-01-01

Annual recruitment of bivalves in the Wadden Sea is usually more successful in summers after cold than after mild winters. The new generation (0-group) of the main predators (shrimps and shore crabs) of early benthic stages of bivalves appear later in spring on tidal flats after colder winters. If

Parasites of economically important bivalves from the southern coast of Bahia State, Brazil Parasitos de bivalves de interesse econômico no Litoral Sul do Estado da Bahia, Brasil

Directory of Open Access Journals (Sweden)

Gabriela Calvi Zeidan

2012-12-01

Full Text Available This study investigated the parasites of three commercially important bivalve species (Crassostrea rhizophorae, Mytella guyanensis and Lucina pectinata from the southern coast of Bahia, Brazil. A total of 540 specimens were collected in August 2009 and February 2010, at three localities. The bivalve specimens were measured on their longest axis, opened, and macroscopically examined for the presence of parasites or signs of disease. They were then fixed in Davidson' solution and subjected to routine histological processing, with paraffin embedding and H&E staining; next, the specimens were examined under a light microscope. No parasites were observed associated with L. pectinata. Rickettsia-like organisms (RLOs, Sphenophrya sp. (Ciliophora, Nematopsis sp. (Apicomplexa, Urastoma sp. (Turbellaria and Bucephalus sp. (Digenea were observed in both C. rhizophorae and M. guyanensis, as well as Ancistrocoma sp. (Ciliophora and Tylocephalum sp. (Cestoda in the former. A high prevalence of Nematopsis sp. was seen, but caused no apparent damage to the host. Bucephalus sp. caused the destruction of tissues, with castration, but showed low prevalence. The other parasites occurred in low prevalence and intensity, without causing significant damage.Neste estudo foram investigados os parasitos de três espécies de bivalves de interesse econômico (Crassostrea rhizophorae, Mytella guyanensis e Lucina pectinata da Bahia. Foram analisados 540 exemplares, obtidos em duas coletas (agosto-2009 e fevereiro-2010, em três localidades. Os bivalves foram medidos quanto ao seu maior eixo, abertos e examinados macroscopicamente quanto à presença de parasitos ou sinais de enfermidades. Depois disso, foram fixados em solução de Davidson e processados por rotina de histologia, com inclusão em parafina e coloração com H&E. O material foi examinado ao microscópio de luz. Nenhum parasito esteve associado a L. pectinata. Bactérias do tipo RLOs (organismos assemelhados a

EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain

Directory of Open Access Journals (Sweden)

Micheál O’Mahony

2018-03-01

Full Text Available Food safety risk assessment in the European Union (EU recognises consumer illness that arises from marine biotoxins as a risk associated with bivalve mollusc consumption. EU food regulations contain various general food safety obligations, which should contribute significantly to managing this risk. EU food regulations additionally impose various specific obligations on both Food Business Operators and Competent Authorities in order to manage the marine biotoxin food safety risk in the bivalve mollusc food-chain. These have a particular focus on the pre-harvest component of the food-chain. A central component of these specific systems is the requirement for ongoing monitoring of phytoplankton and biotoxin concentrations in water and molluscs, respectively. This monitoring explicitly brings a potential outcome of closing production areas delineated by classification to prohibit the harvest of bivalve molluscs as food from those areas when acceptable biotoxin concentrations are exceeded. This review considers the utility of these systems, at conceptual and practical levels, and explores their contribution to an effective regulatory risk management approach.

Field clearance of an intertidal bivalve bed: relative significance of the co-occurring blue mussel Mytilus edulis and Pacific oyster Crassostrea gigas

DEFF Research Database (Denmark)

Vismann, Bent; Holm, Mark Wejlemann; Davids, Jens

2016-01-01

was estimated by combining field measurements of clearance rates and modelling of the bivalve bed (topography, biomass distribution, temporal and spatial water coverage and depth). The average density of C. gigas and M. edulis was 35 ± 36 and 1001 ± 685 ind. m−2, respectively. The water volume cleared during...... a tidal cycle was estimated at 45 838 m3, of which C. gigas and M. edulis contributed 9169 and 36 669 m3, respectively. Therefore, M. edulis contributed 4 times as much as C. gigas to the bivalve bed’s clearance, and the 2 bivalves were estimated to clear the water volume 1.9 times during each tidal cycle....... However, the estimated water column cleared during low tide is overestimated due to phytoplankton depletion. Hence, it is concluded that the bivalve bed clears the water close to 1 time each tidal cycle. This, together with a low dry weight of soft parts, indicates that the bivalve bed, in general...

In situ method for measurements of community clearance rate on shallow water bivalve populations

DEFF Research Database (Denmark)

Hansen, Benni W.; Dolmer, Per; Vismann, Bent

2011-01-01

An open-top chamber was designed for measuring ambient community clearance rate on undisturbed bivalve populations in the field. The chamber was pressed 5-10 cm down in the sediment on the mussel bed. It holds approximately 30-40 cm water column equal to a volume of 43-77 L. It was provided...... with an air lift connected to a SCUBA diver pressure tank generating a continuous and gentle water circulation. This ensures a complete mixture of suspended particles, and thereby, a maximum filtration by the bivalves. An in situ fluorometer was mounted to record plant pigment reduction due to mussel...

Deciphering the link between doubly uniparental inheritance of mtDNA and sex determination in bivalves: Clues from comparative transcriptomics

Science.gov (United States)

Capt, Charlotte; Renaut, Sébastien; Ghiselli, Fabrizio; Milani, Liliana; Johnson, Nathan A.; Sietman, Bernard E.; Stewart, Donald; Breton, Sophie

2018-01-01

Bivalves exhibit an astonishing diversity of sexual systems and sex-determining mechanisms. They can be gonochoric, hermaphroditic or androgenetic, with both genetic and environmental factors known to determine or influence sex. One unique sex-determining system involving the mitochondrial genome has also been hypothesized to exist in bivalves with doubly uniparental inheritance (DUI) of mtDNA. However, the link between DUI and sex determination remains obscure. In this study, we performed a comparative gonad transcriptomics analysis for two DUI-possessing freshwater mussel species to better understand the mechanisms underlying sex determination and DUI in these bivalves. We used a BLAST reciprocal analysis to identify orthologs between Venustaconcha ellipsiformis and Utterbackia peninsularis and compared our results with previously published sex-specific bivalve transcriptomes to identify conserved sex-determining genes. We also compared our data with other DUI species to identify candidate genes possibly involved in the regulation of DUI. A total of ∼12,000 orthologous relationships were found, with 2,583 genes differentially expressed in both species. Among these genes, key sex-determining factors previously reported in vertebrates and in bivalves (e.g., Sry, Dmrt1, Foxl2) were identified, suggesting that some steps of the sex-determination pathway may be deeply conserved in metazoans. Our results also support the hypothesis that a modified ubiquitination mechanism could be responsible for the retention of the paternal mtDNA in male bivalves, and revealed that DNA methylation could also be involved in the regulation of DUI. Globally, our results suggest that sets of genes associated with sex determination and DUI are similar in distantly-related DUI species.

Thyasirid bivalves from Cretaceous and Paleogene cold seeps

Directory of Open Access Journals (Sweden)

Krzysztof Hryniewicz

2017-11-01

Full Text Available We present a systematic study of thyasirid bivalves from Cretaceous to Oligocene seep carbonates worldwide. Eleven species of thyasirid bivalves are identified belonging to three genera: Conchocele, Maorithyas, and Thyasira. Two species are new: Maorithyas humptulipsensis sp. nov. from middle Eocene seep carbonates in the Humptulips Formation, Washington State, USA, and Conchocele kiritachiensis sp. nov. from the late Eocene seep deposit at Kiritachi, Hokkaido, Japan. Two new combinations are provided: Conchocele townsendi (White, 1890 from Maastrichtian strata of the James Ross Basin, Antarctica, and Maorithyas folgeri (Wagner and Schilling, 1923 from Oligocene rocks from California, USA. Three species are left in open nomenclature. We show that thyasirids have Mesozoic origins and appear at seeps before appearing in “normal” marine environments. These data are interpreted as a record of seep origination of thyasirids, and their subsequent dispersal to non-seep environments. We discuss the age of origination of thyasirids in the context of the origin of the modern deep sea fauna and conclude that thyasirids could have deep sea origins. This hypothesis is supported by the observed lack of influence of the Cretaceous and Paleogene Oceanic Anoxic Events on the main evolutionary lineages of the thyasirids, as seen in several other members of the deep sea fauna.

Bivalve grazing, nutrient cycling and phytoplankton dynamics in an estuarine ecosystem

NARCIS (Netherlands)

Prins, T.C.

1996-01-01

This thesis has considered the impact of the suspension feeding bivalve Mytilusedulis on nutrient cycling and phytoplankton in an estuarine ecosystem. The research was started within the framework of an extensive research project with the

An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

NARCIS (Netherlands)

Filgueira, R.; Byron, C.J.; Comeau, L.A.; Jansen, H.M.; Smaal, A.C.

2015-01-01

The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densities,

Labelling and Marketing of Bivalve and Gastropod Molluscs Retailed in Sardinia, Italy Between 2009 and 2013.

Science.gov (United States)

Meloni, Domenico

2015-05-28

The aim of the present survey was to investigate the correct enforcement of the Community rules on the labelling and marketing of bivalve and gastropod molluscs retailed in Sardinia, Italy between 2009 and 2013. A total of 1500 packages and labels for live bivalve and gastropod molluscs were considered. A total of 375 labels (25%) presented non-compliance concerning the wrong trade name and additional wrong or missing information. The highest percentage of anomalous labels has been detected in small-scale retail shops (35%) and open-air markets (25%) compared with the big retailing chains (20%). The 5% of packages were not in compliance with the European Community rules on packaging of bivalve and gastropod molluscs. The high percentage of non-compliance with the European regulations on labelling results is a strong limitation for the consumers and highlights the need to improve the control system about labelling of seafood products.

Growth rates and geochemical proxies in Late Campanian bivalves - New insights from micro-X-ray Fluorescence mapping and numerical growth modelling

Science.gov (United States)

de Winter, Niels; Goderis, Steven; van Malderen, Stijn; Vanhaecke, Frank; Claeys, Philippe

2017-04-01

Understanding the Late Cretaceous greenhouse climate is of vital importance for understanding present and future climate change. While a lot of good work has been done to reconstruct climate in this interesting period, most paleoclimatic studies have focused on long-term climate change[1]. Alternatively, multi-proxy records from marine bivalves provide us with a unique opportunity to study past climate on a seasonal scale. However, previous fossil bivalve studies have reported ambiguous results with regard to the interpretation of trace element and stable isotope proxies in marine bivalve shells[2]. One major problem in the interpretation of such records is the bivalve's vital effect and the occurrence of disequilibrium fractionation during bivalve growth. Both these problems are linked to the annual growth cycle of marine bivalves, which introduces internal effects on the incorporation of isotopes and trace elements into the shell[3]. Understanding this growth cycle in extinct bivalves is therefore of great importance for the interpretation of seasonal proxy records in their shells. In this study, three different species of extinct Late Campanian bivalves (two rudist species and one oyster species) that were found in the same stratigraphic interval are studied. Micro-X-Ray Fluorescence line scanning and mapping of trace elements such as Mg, Sr, S and Zn, calibrated by LA-ICP-MS measurements, is combined with microdrilled stable carbon and oxygen isotope analysis on the well-preserved part of the shells. Data of this multi-proxy study is compared with results from a numerical growth model written in the open-source statistics package R[4] and based on annual growth increments observed in the shells and shell thickness. This growth model is used together with proxy data to reconstruct rates of trace element incorporation into the shell and to calculate the mass balance of stable oxygen and carbon isotopes. In order to achieve this goal, 2D mapping of bivalve shell

The potential accumulation of polycyclic aromatic hydrocarbons in phytoplankton and bivalves in Can Gio coastal wetland, Vietnam.

Science.gov (United States)

Thuy, Hoang Thi Thanh; Loan, Tu Thi Cam; Phuong, Trinh Hong

2018-05-12

Polycyclic aromatic hydrocarbons (PAHs) are one of the most important classes of anthropogenic persistent organic contaminants in the marine environment. This review discusses a whole range of findings that address various aspects of the bioaccumulation of PAHs in two common marine biota (phytoplankton and bivalves) globally and especially for Can Gio coastal wetland, Vietnam. The published information and collected data on the bioconcentration and accumulation mechanisms of PAHs as well as implications for Can Gio coastal wetland are compiled for phytoplankton and bivalves. PAHs are still released to Can Gio coastal environments from various sources and then transported to coastal environments through various physical processes; they may enter marine food chains and be highly accumulated in phytoplankton and bivalves. Thus, PAHs' bioaccumulation should be considered as one important criterion to assess the water's quality, directly linked to human health due to seafood consumption. Ecologically, Can Gio coastal wetland plays an important role to the South Vietnam key economic zone. However, it is also an area of potential PAHs inputs. With the abundant phytoplankton and bivalves in Can Gio coastal wetland, the PAHs bioaccumulation in these biota is inevitably detected. Thus, further study on the bioavailability of these contaminants is urgently needed in order to mitigate their negative effects and protect the ecosystems.

Wood-Boring Bivalves (Mollusca: Teredinidae, Pholadidae) of Pacific coast of Colombia

International Nuclear Information System (INIS)

Cantera K, Jaime R

2010-01-01

Twelve species of wood-boring bivalves, ten of the family Teredinidae and two of family Pholadidae were collected in mangroves at 6 locations of the Pacific coast of Colombia. This paper presents a brief escription of these species, including size, ecological notes and geographical distribution.

Labelling and marketing of bivalve and gastropod molluscs retailed in Sardinia, Italy between 2009 and 2013

Directory of Open Access Journals (Sweden)

Domenico Meloni

2015-06-01

Full Text Available The aim of the present survey was to investigate the correct enforcement of the Community rules on the labelling and marketing of bivalve and gastropod molluscs retailed in Sardinia, Italy between 2009 and 2013. A total of 1500 packages and labels for live bivalve and gastropod molluscs were considered. A total of 375 labels (25% presented non-compliance concerning the wrong trade name and additional wrong or missing information. The highest percentage of anomalous labels has been detected in small-scale retail shops (35% and open-air markets (25% compared with the big retailing chains (20%. The 5% of packages were not in compliance with the European Community rules on packaging of bivalve and gastropod molluscs. The high percentage of non-compliance with the European regulations on labelling results is a strong limitation for the consumers and highlights the need to improve the control system about labelling of seafood products.

Semi-automatic surface sediment sampling system - A prototype to be implemented in bivalve fishing surveys

Science.gov (United States)

Rufino, Marta M.; Baptista, Paulo; Pereira, Fábio; Gaspar, Miguel B.

2018-01-01

In the current work we propose a new method to sample surface sediment during bivalve fishing surveys. Fishing institutes all around the word carry out regular surveys with the aim of monitoring the stocks of commercial species. These surveys comprise often more than one hundred of sampling stations and cover large geographical areas. Although superficial sediment grain sizes are among the main drivers of benthic communities and provide crucial information for studies on coastal dynamics, overall there is a strong lack of this type of data, possibly, because traditional surface sediment sampling methods use grabs, that require considerable time and effort to be carried out on regular basis or on large areas. In face of these aspects, we developed an easy and un-expensive method to sample superficial sediments, during bivalve fisheries monitoring surveys, without increasing survey time or human resources. The method was successfully evaluated and validated during a typical bivalve survey carried out on the Northwest coast of Portugal, confirming that it had any interference with the survey objectives. Furthermore, the method was validated by collecting samples using a traditional Van Veen grabs (traditional method), which showed a similar grain size composition to the ones collected by the new method, on the same localities. We recommend that the procedure is implemented on regular bivalve fishing surveys, together with an image analysis system to analyse the collected samples. The new method will provide substantial quantity of data on surface sediment in coastal areas, using a non-expensive and efficient manner, with a high potential application in different fields of research.

Near infra-red spectroscopy quantitative modelling of bivalve protein, lipid and glycogen composition using single-species versus multi-species calibration and validation sets

Science.gov (United States)

Bartlett, Jill K.; Maher, William A.; Purss, Matthew B. J.

2018-03-01

Near infrared spectroscopy (NIRS) quantitative modelling was used to measure the protein, lipid and glycogen composition of five marine bivalve species (Saccostrea glomerata, Ostrea angasi, Crassostrea gigas, Mytilus galloprovincialis and Anadara trapezia) from multiple locations and seasons. Predictive models were produced for each component using individual species and aggregated sample populations for the three oyster species (S. glomerata, O. angasi and C. gigas) and for all five bivalve species. Whole animal tissues were freeze dried, ground to > 20 μm and scanned by NIRS. Protein, lipid and glycogen composition were determined by traditional chemical analyses and calibration models developed to allow rapid NIRS-measurement of these components in the five bivalve species. Calibration modelling was performed using wavelet selection, genetic algorithms and partial least squares analysis. Model quality was assessed using RPIQ and RMESP. For protein composition, single species model results had RPIQ values between 2.4 and 3.5 and RMSEP between 8.6 and 18%, the three oyster model had an RPIQ of 2.6 and an RMSEP of 10.8% and the five bivalve species had an RPIQ of 3.6 and RMSEP of 8.7% respectively. For lipid composition, single species models achieved RPIQ values between 2.9 and 5.3 with RMSEP between 9.1 and 11.2%, the oyster model had an RPIQ of 3.6 and RMSEP of 6.8 and the five bivalve model had an RPIQ of 5.2 and RMSEP of 6.8% respectively. For glycogen composition, the single species models had RPIQs between 3.8 and 18.9 with RMSEP between 3.5 and 9.2%, the oyster model had an RPIQ of 5.5 and RMSEP of 7.1% and the five bivalve model had an RPIQ of 4 and RMSEP of 7.6% respectively. Comparison between individual species models and aggregated models for three oyster species and five bivalve species for each component indicate that aggregating data from like species produces high quality models with robust and reliable quantitative application. The benefit of

Marine Bivalve Cellular Responses to Beta Blocker Exposures ...

Science.gov (United States)

β blockers are prescription drugs used for medical treatment of hypertension and arrhythmias. They prevent binding of agonists such as catecholamines to β adrenoceptors. In the absence of agonist induced activation of the receptor, adenylate cyclase is not activated which in turn limits cAMP production and protein kinase A activation, preventing increases in blood pressure and arrhythmias. After being taken therapeutically, commonly prescribed β blockers may make their way to coastal habitats via discharge from waste water treatment plants (WWTP) posing a potential risk to aquatic organisms. The aim of our research is to evaluate cellular responses of three commercially important marine bivalves - Eastern oysters, blue mussels and hard clams - upon exposure to two β blocker drugs, propranolol and metoprolol, and to find molecular initiating events (MIEs) indicative of the exposure. Bivalves were obtained from Narragansett Bay (Rhode Island, USA) and acclimated in the laboratory. Following acclimation, gills and hepatopancreas (HP) tissues were harvested and separately exposed to 0, 1, 10, 100 and 1000 ng/l of each drug. Tissues were bathed in 30 parts per thousand (ppt) filtered seawater, antibiotic mix, Leibovitz nutrient media, and the test drug. Exposures were conducted for 24 hours and samples were saved for cellular biomarker assays. A lysosomal destabilization assay, which is a marker of membrane damage, was also performed at the end of each exposure.

Distribution of organotin compounds in the bivalves of the Aegean Sea, Greece

NARCIS (Netherlands)

Chandrinou, S.; Pappas, K.; Nikolaou, A.; Stasinakis, A.S.; Wegener, J.W.M.; Alexandropoulos, Th.; Thomaidis, N.S.

2007-01-01

Five bivalve species - Mytilus galloprovinciallis (Mediterranean mussels), Venus gallina (stripped venus), Modiola barbatus L. (bearded horse mussels), Pecten jacobeus (scallops) and Callista chione (hard clams) - were collected from seven areas in Aegean Sea, Greece, between August 2001 and January

Indian marine bivalves: Potential source of antiviral drugs

Digital Repository Service at National Institute of Oceanography (India)

Chatterji, A.; Ansari, Z.A.; Ingole, B.S.; Bichurina, M.A.; Sovetova, M.; Boikov, Y.A.

in large quantities by traditional methods and sold live in the market for human consumption. The economically important sp e cies of marine bivalves are green mussel ( Perna viridis ), e s tuarine oyster ( Crassostrea madrasensis ), giant oyster... in developing an effecti ve drug has been the unique characteristics of antigenic variation of virus resulting in the emergence of new variant virus strains 14 . There are a number of antiviral drugs introduced in the market such as tricyclic sy m- metric...

Adaptive morphologies and guild structure in a high-diversity bivalve fauna from an early Campanian rocky shore, Ivö Klack (Sweden)

DEFF Research Database (Denmark)

Sørensen, Anne Mehlin; Surlyk, Finn; Jagt, John W. M.

2012-01-01

habitats. Study of the functional morphology of bivalve shells and comparison with extant relatives has resulted in a subdivision of the fauna into seven guilds and five habitats. The bivalve fauna represents a withinhabitat, time-averaged assemblage to which none of the species was introduced from...

Comparative in vitro study on free radical scavenging potential of selected bivalve species

Digital Repository Service at National Institute of Oceanography (India)

Shenai-Tirodkar, P.S.; Pawar, R.T.; Jagtap, T.G.

Bivalves such as, Crassostrea spp., Meretrix casta, Placuna placenta and Polymesoda erosa are largely consumed as edible seafood. It forms natural source of nutrition in coastal and worldwide population. Free radical scavenging activities...

Chemosynthetic bacteria found in bivalve species from mud volcanoes of the Gulf of Cadiz.

Science.gov (United States)

Rodrigues, Clara F; Webster, Gordon; Cunha, Marina R; Duperron, Sébastien; Weightman, Andrew J

2010-09-01

As in other cold seeps, the dominant bivalves in mud volcanoes (MV) from the Gulf of Cadiz are macrofauna belonging to the families Solemyidae (Acharax sp., Petrasma sp.), Lucinidae (Lucinoma sp.), Thyasiridae (Thyasira vulcolutre) and Mytilidae (Bathymodiolus mauritanicus). The delta(13)C values measured in solemyid, lucinid and thyasirid specimens support the hypothesis of thiotrophic nutrition, whereas isotopic signatures of B. mauritanicus suggest methanotrophic nutrition. The indication by stable isotope analysis that chemosynthetic bacteria make a substantial contribution to the nutrition of the bivalves led us to investigate their associated bacteria and their phylogenetic relationships based on comparative 16S rRNA gene sequence analysis. PCR-denaturing gradient gel electrophoresis analysis and cloning of bacterial 16S rRNA-encoding genes confirmed the presence of sulfide-oxidizing symbionts within gill tissues of many of the studied specimens. Phylogenetic analysis of bacterial 16S rRNA gene sequences demonstrated that most bacteria were related to known sulfide-oxidizing endosymbionts found in other deep-sea chemosynthetic environments, with the co-occurrence of methane-oxidizing symbionts in Bathymodiolus specimens. This study confirms the presence of several chemosynthetic bivalves in the Gulf of Cadiz and further highlights the importance of sulfide- and methane-oxidizing symbionts in the trophic ecology of macrobenthic communities in MV.

Distribution of DTHS3 satellite DNA across 12 bivalve species Eva ...

Indian Academy of Sciences (India)

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In this work, characterization of DTHS3 satellite DNA was further expanded within the Class. Bivalvia. Monomer variants of DTHS3 satDNA were compared in 12 bivalve species belonging to two different Subclasses, Heterodonta and Pteriomorphia. This satDNA, whose age is estimated to a minimum of 516 Ma, ...

Feeding current characteristics of three morphologically different bivalve suspension feeders, Crassostrea gigas, Mytilus edulis and Cerastoderma edule, in relation to food competition

NARCIS (Netherlands)

Troost, K.; Stamhuis, E.J.; van Duren, L.A; Wolff, W.J.

Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable. This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual

Feeding current characteristics of three morphologically different bivalve suspension feeders, Crassostrea gigas Mytilus edulis and Cerastoderma edule , in relation to food competition

NARCIS (Netherlands)

Troost, K.; Stamhuis, E.J.; Duren, L.A.; Wolff, W.

2009-01-01

Introduced Pacific oysters (Crassostrea gigas) have shown rapid expansion in the Oosterschelde estuary, while stocks of native bivalves declined slightly or remained stable. This indicates that they might have an advantage over native bivalve filter feeders. Hence, at the scale of individual

Contamination in sediments, bivalves and sponges of McMurdo Sound, Antarctica

Energy Technology Data Exchange (ETDEWEB)

Negri, Andrew [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia)]. E-mail: a.negri@aims.gov.au; Burns, Kathryn [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Boyle, Steve [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Brinkman, Diane [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Webster, Nicole [Australian Institute of Marine Science, PMB 3, Townsville, Qld (Australia); Biological Sciences, University of Canterbury, Christchurch (New Zealand)

2006-10-15

This study examined the concentrations of total hydrocarbons (THC), polychlorinated biphenyls (PCB), polyaromatic hydrocarbons (PAH), and trace metals (Cu, Zn, Cd, Pb, Hg and As) in marine sediments off Scott Base (NZ) and compared them with sediments near the highly polluted McMurdo Station (US) as well as less impacted sites including Turtle Rock and Cape Evans. The Antarctic mollusc, Laternula elliptica and three common sponge species were also analysed for trace metals. The mean THC concentration in sediments from Scott Base was 3 fold higher than the pristine site, Turtle Rock, but 10 fold lower than samples from McMurdo Station. McMurdo Station sediments also contained the highest concentrations of PAHs, PCBs and the trace metals, Cu, Zn, Pb, Cd and Hg. Copper was significantly higher in bivalves from McMurdo Station than other sites. Trace metal concentrations in sponges were generally consistent within sites but no spatial patterns were apparent. - Analyses of Antarctic marine sediments, bivalves and sponges revealed strong PAH, PCB and trace metal gradients in McMurdo Sound.

Contamination in sediments, bivalves and sponges of McMurdo Sound, Antarctica

International Nuclear Information System (INIS)

Negri, Andrew; Burns, Kathryn; Boyle, Steve; Brinkman, Diane; Webster, Nicole

2006-01-01

This study examined the concentrations of total hydrocarbons (THC), polychlorinated biphenyls (PCB), polyaromatic hydrocarbons (PAH), and trace metals (Cu, Zn, Cd, Pb, Hg and As) in marine sediments off Scott Base (NZ) and compared them with sediments near the highly polluted McMurdo Station (US) as well as less impacted sites including Turtle Rock and Cape Evans. The Antarctic mollusc, Laternula elliptica and three common sponge species were also analysed for trace metals. The mean THC concentration in sediments from Scott Base was 3 fold higher than the pristine site, Turtle Rock, but 10 fold lower than samples from McMurdo Station. McMurdo Station sediments also contained the highest concentrations of PAHs, PCBs and the trace metals, Cu, Zn, Pb, Cd and Hg. Copper was significantly higher in bivalves from McMurdo Station than other sites. Trace metal concentrations in sponges were generally consistent within sites but no spatial patterns were apparent. - Analyses of Antarctic marine sediments, bivalves and sponges revealed strong PAH, PCB and trace metal gradients in McMurdo Sound

Availability of pearl producing marine bivalves in south-eastern coast of Bangladesh and culture potentialities

Directory of Open Access Journals (Sweden)

Md Ataur Rahman

2015-12-01

Full Text Available The present study was conducted during September 2014 to July 2015 to identify the pearl bearing bivalves in south-eastern coast of Bangladesh and culture potentialities of marine oyster in captivity based on field investigation. A total of 7 pearl bearing bivalve species were identified in the coast with a salinity of 18-34 ppt, pH 8.1-8.3 and water depth ranged 0.2-2.0 meter in their habitat. From the collected bivalves, most abundant oyster species windowpane oyster, Placuna placenta (Linnaeus, 1758 was reared in fiber glass tanks with seawater for a period of 6 months. During rearing highest survival rate of 88% was observed in T1 with sandy and gravel substratum and lowest survival rate of 78% was found in T2 with muddy substratum. Average temperature and salinity were varied between 24 °C-25 °C and 21-26 ppt respectively. From the reared oyster, highest 54 nos. small pearls in the month of April and lowest 7 pearls in December from a single P. placenta were obtained. The study proved that pearls can be obtained from the marine oysters in captivity in Bangladesh, and this offers large scale culture potentialities in our coast.

Climate change and body size shift in Mediterranean bivalve assemblages: unexpected role of biological invasions.

Science.gov (United States)

Nawrot, Rafał; Albano, Paolo G; Chattopadhyay, Devapriya; Zuschin, Martin

2017-08-16

Body size is a synthetic functional trait determining many key ecosystem properties. Reduction in average body size has been suggested as one of the universal responses to global warming in aquatic ecosystems. Climate change, however, coincides with human-enhanced dispersal of alien species and can facilitate their establishment. We address effects of species introductions on the size structure of recipient communities using data on Red Sea bivalves entering the Mediterranean Sea through the Suez Canal. We show that the invasion leads to increase in median body size of the Mediterranean assemblage. Alien species are significantly larger than native Mediterranean bivalves, even though they represent a random subset of the Red Sea species with respect to body size. The observed patterns result primarily from the differences in the taxonomic composition and body-size distributions of the source and recipient species pools. In contrast to the expectations based on the general temperature-size relationships in marine ectotherms, continued warming of the Mediterranean Sea indirectly leads to an increase in the proportion of large-bodied species in bivalve assemblages by accelerating the entry and spread of tropical aliens. These results underscore complex interactions between changing climate and species invasions in driving functional shifts in marine ecosystems. © 2017 The Author(s).

Comparative sensitivity of European native (Anodonta anatina) and exotic (Corbicula fluminea) bivalves to mercury

Science.gov (United States)

Oliveira, Patrícia; Lopes-Lima, Manuel; Machado, Jorge; Guilhermino, Lúcia

2015-12-01

Pollution is believed to be an important factor modulating the competition between exotic invasive bivalves and their native competitors. Thus, the objective of the present study was to compare the sensitivity of the European native Anodonta anatina and the exotic invasive species Corbicula fluminea to mercury, a ubiquitous environmental contaminant of high concern. In laboratory acute bioassays, adult organisms of both species were exposed independently to mercury for 96 h (31-500 μg/L). The criteria indicative of toxicity were mortality and biomarkers of oxidative stress and damage, neurotoxicity, and energy production changes. Mercury induced mortality in A. anatina (72 h-LC10 and 72 h-LC50 of 14.0 μg/L and 49.6 μg/L, respectively) but not in C. fluminea. The ability of C. fluminea to maintaining the shell closed for considerable periods of time when exposed to high concentrations of mercury and the effective activation (up to 63 μg/L) of mechanisms against the oxidative stress caused by mercury may have contributed to its relatively low sensitivity. In the range of concentrations tested, mercury had no significant effects on the other parameters analysed in C. fluminea. Overall, the findings of the present study, suggest that in real scenarios of competition between C. fluminea and A. anatina populations, the presence of mercury may modulate the process, acting in favour of the exotic species because it is less sensitive to this environmental contaminant than the native bivalve. The results of the present study highlight the need of further investigation on the effects of mercury on the competition between exotic invasive species and their native competitors, especially the effects potentially induced by long-term exposure to low concentrations of this metal, the mechanisms involved in the tolerance to mercury-induced stress, and the potential post-exposure recovery of both exotic invasive and native bivalves. This knowledge is most important for

Ecology of megabenthic bivalve communities from sandy beaches on the south coast of Portugal

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Marta M. Rufino

2010-03-01

Full Text Available Ecological aspects of 75 megabenthic bivalve species found on the south coast of Portugal (from Vila Real to Sagres were studied based on the information provided by seasonal bivalve surveys from 2000 to 2007 (8600 hauls, simultaneously using a razor shell dredge and a clam dredge. Of the 75 species identified, 36 occurred less than 30 times, and thus were considered rare in the area. The remaining 39 bivalves were analysed according to their occurrence, bathymetric distribution, geographic preferences, seasonal preferences, burying-depth, beach exposure and river mouth proximity. All species belonging to the Pharidae and Solenidae families (razor shells and most Tellinidae were significantly more frequent in the razor shell dredge (indicating deeper burying in the sediment, whilst the families Cardiidae and Donacidae were significantly more frequent in the clam dredge (indicating that these species are probably closer to the sediment surface. As for the season, most bivalve species occurred similarly in both seasons (19 sp; 49%, but a large proportion were more abundant during the autumn surveys (17 sp., 44%, whereas only three species were commoner during the spring surveys. Most species belonging to the families Cardiidae and Mactridae were commoner in the autumn surveys. The spatial distribution differed between species and cluster analysis identified four communities with greater geographic affinity. Species belonging to the family Cardiidae were preferably found in the western part (WB and the eastern part (S of the study area, whereas the families Donacidae, Mactridae and Tellinidae occurred mainly in the central area (EB and the eastern (S coastal sectors. Overall, shallower species (modal depth at 3-6 m showed greater occurrences and abundances than the deeper ones, and the depth pattern observed did not change between seasons. Donacidae and Mactridae (except Mactra glauca were represented essentially by shallow species, whereas

Molecular and Biochemical Methods Useful for the Epigenetic Characterization of Chromatin-Associated Proteins in Bivalve Molluscs

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Ciro Rivera-Casas

2017-08-01

Full Text Available Bivalve molluscs constitute a ubiquitous taxonomic group playing key functions in virtually all ecosystems, and encompassing critical commercial relevance. Along with a sessile and filter-feeding lifestyle in most cases, these characteristics make bivalves model sentinel organisms routinely used for environmental monitoring studies in aquatic habitats. The study of epigenetic mechanisms linking environmental exposure and specific physiological responses (i.e., environmental epigenetics stands out as a very innovative monitoring strategy, given the role of epigenetic modifications in acclimatization and adaptation. Furthermore, the heritable nature of many of those modifications constitutes a very promising avenue to explore the applicability of epigenetic conditioning and selection in management and restoration strategies. Chromatin provides a framework for the study of environmental epigenetic responses. Unfortunately, chromatin and epigenetic information are very limited in most non-traditional model organisms and even completely lacking in most environmentally and ecologically relevant organisms. The present work aims to provide a comprehensive and reproducible experimental workflow for the study of bivalve chromatin. First, a series of guidelines for the molecular isolation of genes encoding chromatin-associated proteins is provided, including information on primers suitable for conventional PCR, Rapid Amplification of cDNA Ends (RACE, genome walking and quantitative PCR (qPCR experiments. This section is followed by the description of methods specifically developed for the analysis of histone and SNBP proteins in different bivalve tissues, including protein extraction, purification, separation and immunodetection. Lastly, information about available antibodies, their specificity and performance is also provided. The tools and protocols described here complement current epigenetic analyses (usually limited to DNA methylation by incorporating

Expression Study of LeGAPDH, LeACO1, LeACS1A, and LeACS2 in Tomato Fruit (Solanum lycopersicum

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Pijar Riza Anugerah

2015-10-01

Full Text Available Tomato is a climacteric fruit, which is characterized by ripening-related increase of respiration and elevated ethylene synthesis. Ethylene is the key hormone in ripening process of climacteric fruits. The objective of this research is to study the expression of three ethylene synthesis genes: LeACO1, LeACS1A, LeACS2, and a housekeeping gene LeGAPDH in ripening tomato fruit. Specific primers have been designed to amplify complementary DNA fragment of LeGAPDH (143 bp, LeACO1 (240 bp, LeACS1A (169 bp, and LeACS2 (148 bp using polymerase chain reaction. Nucleotide BLAST results of the complementary DNA fragments show high similarity with LeGAPDH (NM_001247874.1, LeACO1 (NM_001247095.1, LeACS1A (NM_001246993.1, LeACS2 (NM_001247249.1, respectively. Expression study showed that LeACO1, LeACS1A, LeACS2, and LeGAPDH genes were expressed in ripening tomato fruit. Isolation methods, reference sequences, and primers used in this study can be used in future experiments to study expression of genes responsible for ethylene synthesis using quantitative polymerase chain reaction and to design better strategy for controlling fruit ripening in agroindustry.

Light indirectly mediates bivalve habitat modification and impacts on seagrass

DEFF Research Database (Denmark)

Castorani, Max C. N.; Glud, Ronnie; Hasler-Sheetal, Harald

2015-01-01

Environmental context may influence the sign, strength, andmechanisms of species interactions but few studies have experimentally tested the potential for abiotic conditions to mediate interactions through multiple cooccurring stress pathways. Abiotic conditionsmay mediate species interactions...... by directly or indirectly influencing the effects of habitat-modifying organisms that are capable of simultaneously ameliorating and exacerbating multiple stressors. Itwas hypothesized that light availability changes seagrassmetabolismand thereby indirectly regulates bivalve habitat modification...

Le laboratoire, le temple et le marché

International Development Research Centre (IDRC) Digital Library (Canada)

De manière générale, les auteurs insistent sur le fait que c'est leur foi qui leur a .... nettement que dans de nombreux cercles, le besoin était vivement ressenti de ... Le Dr Kapur présente tout d'abord une brève discussion sur sa vision du ...... pour les soins aux enfants orphelins et aux pauvres et pour la renaissance des ...

Le rôle des chefs traditionnels au Ghana : un modèle inspirant ...

International Development Research Centre (IDRC) Digital Library (Canada)

8 févr. 2011 ... Avec ses partenaires du Sud, avec aussi le soutien du Centre de recherches pour le développement international ( CRDI ), organisme canadien, Ray a étudié le rôle des chefs traditionnels au Ghana dans la lutte contre le VIH et le sida. Les collectivités politiques antérieures au colonialisme sont une ...

An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

DEFF Research Database (Denmark)

Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche

2012-01-01

for bivalve aquaculture be based on a tiered indicator monitoring system that is structured on the principle that increased environmental risk requires increased monitoring effort. More than 1 threshold for each indicator would permit implementation of predetermined impact prevention and mitigation measures......An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social...... and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–environment interactions and policy-related developments and decisions. The Drivers-Pressures-State Change-Impact-Response...

Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety.

Science.gov (United States)

Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

2016-01-21

To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd(2+)/Ca(2+) in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

Characterizing Photosymbiosis Between Fraginae Bivalves and Symbiodinium Using Phylogenetics and Stable Isotopes

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Jingchun Li

2018-04-01

Full Text Available Photosymbiotic associations between heterotrophic hosts and photosynthetic algae play crucial roles in maintaining the trophic and structural integrity of coral reef ecosystems. The marine bivalve subfamily Fraginae contains both non-symbiotic and photosymbiotic lineages, making it an ideal comparative system to study the origin and evolutionary adaptations of photosymbiosis. The symbiotic species exhibit unique morphological adaptations to photosymbiosis. However, the basic biology of these photosymbiotic relationships, such as symbiont diversity and nutritional benefits, has not been thoroughly characterized. In this study, we examined the general morphology of four Fraginae species occupying different depths (0–10 m: Corculum cardissa, Fragum fragum, Fragum scruposum, and Fragum sueziense. Abundant symbionts were found in the mantle, gill, and part of the foot, contained in tubular networks within host tissues. We used molecular phylogenetics to investigate the algal symbiont community of these Fraginae species. Results showed that symbionts from all four species are dinoflagellates belonging to the Symbiodinium clade C and we did not detect any host-specific or geographic-specific genetic structures within the symbionts. We also used stable carbon isotope analyses to examine whether the cockles are directly utilizing photosynthetically derived carbon sources. All species show less depleted 13C compared to filter-feeding bivalves, suggesting at least part of their organic carbon is derived directly from the symbionts. However, 13C depletion of Fragum sueziense collected from deeper habitats are less distinguishable from filter-feeding bivalves. This indicates that species in deeper habitats may rely less on photosymbiosis due to the reduced light availability. Given that the symbiotic fragines exhibit varying morphologies, habitats, and utilization of symbiont photosynthesis, the subfamily represents an ideal model system to study

High pressure processing of bivalve shellfish and HPP's potential use as a virus intervention

Science.gov (United States)

Bivalve shellfish readily bioconcentrate pathogenic microbes and substance, such as algal and dinoflagulate toxins, fecal viruses and bacteria, and naturally present vibrio bacteria. High pressure processing (HPP) is currently used as an intervention for Vibrio vulnificus bacteria within molluscan ...

Dinophysis caudata generated lipophilic shellfish toxins in bivalves from the Nanji Islands, East China Sea

Science.gov (United States)

Jiang, Tao; Xu, Yixiao; Li, Yang; Qi, Yuzao; Jiang, Tianjiu; Wu, Feng; Zhang, Fan

2014-01-01

A 12-month program of monitoring potentially toxic microalgae (that produce lipophilic shellfish toxins; LSTs) and their toxins in bivalves was conducted from April 2006 to March 2007 in the Nanji Islands, East China Sea. Two Dinophysis species, D. caudata and D. acuminata, were identified, and D. caudata was found to be the dominant species. D. caudata was detected in water samples between April and June 2006, and between February and March 2007. It reached its highest abundances in May, with a mean abundance of 1.38×102 cells/L in surface water and 1.25×102 cells/L in bottom water (cultured bivalves sampled between April and June were contaminated with LSTs, with an average toxicity of 85 μg okadaic acid (OA) eq./100 g meat, which was four times higher than the Chinese regulatory limit (20 μg OA eq./100 g meat). Ten out of fifteen wild samples (66.7%) collected during the same period were positive for LSTs, and contained an average LST toxicity of 45 μg OA eq./100 g meat (more than twice the regulatory value). Cultured Patinopecten yessoensis collected on 15 May 2006 had the highest toxicity, 320 μg OA eq./100 g meat, and relatively high toxicities (80 to 160 μg OA eq./100 g meat) were found in bivalves until the end of July.

Investigation into Cryptosporidium and Giardia in bivalve mollusks farmed in Sardinia region and destined for human consumption

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Tiziana Tedde

2013-06-01

Full Text Available Cryptosporidium and Giardia are protozoan parasites transmitted by fecal-oral ingestion of (oocysts, and are responsible for enteritis in several animal species and humans worldwide. These (oocysts can survive for over a year in aquatic environments and can accumulate in bivalve mollusks, which filter large volumes of water. The aim of this study is to evaluate the natural occurrence of Cryptosporidium and Giardia contamination in different specimens of edible bivalves mollusks from farming sites of the western and north-eastern coasts of Sardinia. From April 2011 to February 2012, 1095 specimens of Mytilus galloprovincialis and 240 of Crassostrea gigas were sampled from Olbia and Oristano gulf and San Teodoro pond. Hepatopancreas and gills, including the labial palp, were examined for oocysts and cysts after pooling and homogenisation using different techniques: i staining for light and fluorescence microscopy; ii direct immunofluorescence (IF Merifluor® test Cryptosporidium/ Giardia (Meridian Bioscience Inc., Cincinnati, OH, USA; and iii molecular procedures. However, in the context under study, all mollusks examined with the three main diagnostic techniques were negative for both parasites pointing out the hypothetically low zoonotic risk related to Cryptosporidium and Giardia in bivalves, especially Mytilus galloprovincialis and Crassostrea gigas.

Biochemical and behavioural responses of the endobenthic bivalve Scrobicularia plana to silver nanoparticles in seawater and microalgal food.

Science.gov (United States)

Buffet, Pierre-Emmanuel; Pan, Jin-Fen; Poirier, Laurence; Amiard-Triquet, Claude; Amiard, Jean-Claude; Gaudin, Pierre; Risso-de Faverney, Christine; Guibbolini, Marielle; Gilliland, Douglas; Valsami-Jones, Eugenia; Mouneyrac, Catherine

2013-03-01

Because of their bactericidal effects, Ag nanoparticles (Ag NPs) have promising industrial development but could lead to potential ecological risks. The aim of this study was to examine the uptake and effect of silver (soluble or as lactate Ag NPs of 40 nm) at low concentrations (10 μg L(-1)) in the endobenthic bivalve Scrobicularia plana exposed, for 14 days, directly (water) or via the diet (microalgae). The stability of Ag NPs in seawater was examined using dynamic light scattering. Release of soluble Ag from Ag NPs in the experimental media was quantified by using diffusive gradient in thin film. Bioaccumulation of Ag in bivalves was measured by electrothermal atomic absorption spectrometry. Behavioural and biochemical biomarkers were determined in bivalves. Aggregation of Ag NPs and the release of soluble Ag from Ag NPs were observed in the experimental media. For both forms of Ag, bioaccumulation was much more important for waterborne than for dietary exposure. The response of oxidative stress biomarkers (catalase, glutathion S-transferase, superoxide dismutase) was more important after dietary than waterborne exposure to Ag (soluble and NPs). These defences were relatively efficient since they led to a lack of response of damage biomarkers. Burrowing was not affected for bivalves exposed directly or through the diet to both Ag forms but feeding behaviour was impaired after 10 days of dietary exposure. Since no differences of responses to Ag either soluble or nanoparticulate were observed, it seems that labile Ag released from Ag NPs was mainly responsible for toxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

Assessment of Heavy Metals in Bivalves Molluscs of Apulian Region: a 3-years control activity of a EU Laboratory

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Miedico O.

2013-04-01

Full Text Available The bivalve molluscs represent an important matrix to be studied for several reasons. Their nutritional properties make them valuable to the consumers, so that their consumption and commercial value has risen worldwide. Simultaneously, their significant water-filtering capability and their persistence in the same place make them good bio-indicators of marine ecosystems. The presence of the heavy metal contaminants, as Cd, Pb and Hg, was investigated in bivalve molluscs such as mussels (Mytilus galloprovincialis, clams (Venus gallina and oysters (Ostrea edulis. In the present study, a survey was carried out on 334 samples addressed to the Istituto Zooprofilattico Sperimentale – Puglia e Basilicata, Foggia (ITALY between 2009-2011, and collected by official authorities along the coasts of Apulia Region. The conformity of heavy metal content in bivalve molluscs was verified, in according to EC Reg. 1881/2006. The compliance was found for the total amount of samples. The obtained data on heavy metals concentration in bivalve molluscs were compared with data found in monitoring studies on the incidence of heavy metals in 1981 in North-Western Mediterranean Sea, in 2003 in Tyrrhenian Sea and in 2010 in Pacific Ocean (Chile, reported in literature. The information obtained from this work offer an essential database, not only for the authorities involved in food control, but also for the official institutions responsible of a constant control of the marine ecosystem pollution.

[Nutrition and biological value of food parts of a trade bivalve mollusk Anadara broughtoni].

Science.gov (United States)

Tabakaeva, O V; Tabakaev, A V

2015-01-01

Currently, the human diet includes different new products of seafishing, including non-fish--bivalves and gastropods, holothurias, echinoderms, jellyfishes that demands careful studying of their chemical composition. The purpose of the study was to determine the nutritional and biological value of all soft parts of the burrowing bivalve MOLLUSK Anadara broughtoni from the Far East region. It was established thatfood parts of a bivalve were significantly flooded (water content--73.5-84.2%), with the minimum water content in the adductor and maximum in the mantle. Dry solids are presented by organic (89-93%) and mineral (7-11%) components. Organic components consist of protein (14.6-20.7%), lipids (1.8-2.3%), carbohydrates (2.1-2.6%). The analysis of amino-acid composition of proteins of food parts of the mollusk of Anadara broughtonishowed the presence of all essential amino acids with slight differences in their content depending on the localization of the protein. All edible parts have tryptophan as the limiting amino acid. Muscle proteins have maximum level of lysine, methionine, cysteine, phenylalanine and tyrosine; mantle proteins--leucine, isoleucine and threonine; adductor proteins--valine, phenylalanine, tyrosine, methionine and cysteine. Predominant nonessential amino acids forproteins of all food pieces are glycine, aspartic acid, glutamic acid, arginine. The coefficient of amino-acid score differences of adductor protein (31.7%) is less than the same of cloak by 3.7%. The indicator "biological value" is maximal for adductor (68.3%), but the differenceformuscle is only 0.83%. Mantle proteins are characterized by minimum biological value (64.6%). The coefficient of utility of amino acid composition of protein is maximalfor muscle (57.83%), and values for a cloak and an adductor differ slightly (55.81 and 55.96%). Taurine content in food parts of a mollusk Anadara broughtoni is rather high compared to with other bivalve mollusks of the Far East region

Evaluation of the threat of marine CO2 leakage-associated acidification on the toxicity of sediment metals to juvenile bivalves

International Nuclear Information System (INIS)

Basallote, M. Dolores; Rodríguez-Romero, Araceli; De Orte, Manoela R.; Del Valls, T. Ángel; Riba, Inmaculada

2015-01-01

Highlights: • Short-term tests using juveniles of bivalves to study the effects of CO 2 dissolved. • CO 2 causes effects if the threshold concentration of the organism is overlapped. • Flows of escaped CO 2 would affect the geochemical composition of sediment–seawater. • CO 2 -induced acidification would affect differently to marine sediment toxicity. - Abstract: The effects of the acidification associated with CO 2 leakage from sub-seabed geological storage was studied by the evaluation of the short-term effects of CO 2 -induced acidification on juveniles of the bivalve Ruditapes philippinarum. Laboratory scale experiments were performed using a CO 2 -bubbling system designed to conduct ecotoxicological assays. The organisms were exposed for 10 days to elutriates of sediments collected in different littoral areas that were subjected to various pH treatments (pH 7.1, 6.6, 6.1). The acute pH-associated effects on the bivalves were observed, and the dissolved metals in the elutriates were measured. The median toxic effect pH was calculated, which ranged from 6.33 to 6.45. The amount of dissolved Zn in the sediment elutriates increased in parallel with the pH reductions and was correlated with the proton concentrations. The pH, the pCO 2 and the dissolved metal concentrations (Zn and Fe) were linked with the mortality of the exposed bivalves

Rapport sur le développement dans le monde sur le thème du rôle ...

International Development Research Centre (IDRC) Digital Library (Canada)

... rural et sont tributaires principalement de l'agriculture pour assurer leur subsistance. Ce projet permettra de veiller à ce qu'une place soit accordée aux travaux de recherche financés par le CRDI, aux points de vue différents et aux auteurs de l'hémisphère Sud dans le Rapport sur le développement dans le monde 2008.

Burrowing Behavior of a Deposit Feeding Bivalve Predicts Change in Intertidal Ecosystem State

NARCIS (Netherlands)

Compton, T.J.; Bodnar, W.; Koolhaas, A.; Dekinga, A.; Holthuijsen, S.; Ten Horn, J.; McSweeney, N.; van Gils, J.A.; Piersma, T.

2016-01-01

Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is

Burrowing behavior of a deposit feeding bivalve predicts change in intertidal ecosystem state

NARCIS (Netherlands)

Compton, Tanya J.; Bodnar, Wanda; Koolhaas, Anita; Dekinga, Anne; Holthuijsen, Sander; ten Horn, Job; McSweeney, Niamh; van Gils, Jan; Piersma, Theunis

2016-01-01

Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is

Chemosymbiotic bivalves from the mud volcanoes of the Gulf of Cadiz, NE Atlantic, with descriptions of new species of Solemyidae, Lucinidae and Vesicomyidae.

Science.gov (United States)

Olive, Graham; Rodrigues, Clara F; Cunha, Marina R

2011-01-01

The chemosymbiotic bivalves collected from the mud volcanoes of the Gulf of Cadiz are reviewed. Of the thirteen species closely associated with chemosynthetic settings two Solemyidae, Solemya (Petrasma) elarraichensissp. n. and Acharax gadiraesp. n., one Lucinidae, Lucinoma asapheussp. n., and one Vesicomyidae, Isorropodon megadesmussp. n. are described and compared to close relatives of their respective families. The biodiversity and distribution of the chemosymbiotic bivalves in the Gulf of Cadiz are discussed and compared to the available information from other cold seeps in the Eastern Atlantic and Mediterranean. Although there is considerable similarity at the genus level between seep/mud volcano fields in the Eastern Atlantic and Mediterranean, there is little overlap at the species level. This indicates a high degree of endemism within chemosymbiotic bivalve assemblages.

Zoochorous dispersal of freshwater bivalves: an overlooked vector in biological invasions?

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Coughlan Neil E.

2017-01-01

Full Text Available Vectors that underpin the natural dispersal of invasive alien species are frequently unknown. In particular, the passive dispersal (zoochory of one organism (or propagule by another, usually more mobile animal, remains poorly understood. Field observations of the adherence of invasive freshwater bivalves to other organisms have prompted us to assess the importance of zoochory in the spread of three prolific invaders: zebra mussel Dreissena polymorpha; quagga mussel Dreissena bugensis; and Asian clam Corbicula fluminea. An extensive, systematic search of the literature was conducted across multiple on-line scientific databases using various search terms and associated synonyms. In total, only five publications fully satisfied the search criteria. It appears that some fish species can internally transport viable adult D. polymorpha and C. fluminea specimens. Additionally, literature indicates that veligers and juvenile D. polymorpha can adhere to the external surfaces of waterbirds. Overall, literature suggests that zoochorous dispersal of invasive bivalves is possible, but likely a rare occurrence. However, even the establishment of a few individuals (or a single self-fertilising C. fluminea specimen can, over-time, result in a substantial population. Here, we highlight knowledge gaps, identify realistic opportunities for data collection, and suggest management protocols to mitigate the spread of invasive alien species.

Subcellular partitioning of cadmium in the freshwater bivalve, Pyganodon grandis, after separate short-term exposures to waterborne or diet-borne metal

Energy Technology Data Exchange (ETDEWEB)

Cooper, Sophie; Hare, Landis [INRS-Eau, Terre et Environnement, Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada); Campbell, Peter G.C., E-mail: peter.campbell@ete.inrs.ca [INRS-Eau, Terre et Environnement, Universite du Quebec, 490 rue de la Couronne, Quebec, QC, G1K 9A9 (Canada)

2010-11-15

The dynamics of cadmium uptake and subcellular partitioning were studied in laboratory experiments conducted on Pyganodon grandis, a freshwater unionid bivalve that shows promise as a biomonitor for metal pollution. Bivalves were collected from an uncontaminated lake, allowed to acclimate to laboratory conditions ({>=}25 days), and then either exposed to a low, environmentally relevant, concentration of dissolved Cd (5 nM; 6, 12 and 24 h), or fed Cd-contaminated algae ({approx}70 nmol Cd g{sup -1} dry weight; 4 x 4 h). In this latter case, the bivalves were allowed to depurate for up to 8 days after the end of the feeding phase. As anticipated, the gills were the main target organ during the aqueous Cd exposure whereas the intestine was the initial site of Cd accumulation during the dietary exposure; during the subsequent depuration period, the dietary Cd accumulated in both the digestive gland and in the gills. For the gills, the distribution of Cd among the subcellular fractions (i.e., granules > heat-denatured proteins (HDP) {approx} heat-stable proteins (HSP) > mitochondria {approx} lysosomes + microsomes) was insensitive to the exposure route; both waterborne and diet-borne Cd ended up largely bound to the granule fraction. The subcellular distribution of Cd in the digestive gland differed markedly from that in the gills (HDP > HSP {approx} granules {approx} mitochondria > lysosomes + microsomes), but as in the case of the gills, this distribution was relatively insensitive to the exposure route. For both the gills and the digestive gland, the subcellular distributions of Cd differed from those observed in native bivalves that are chronically exposed to Cd in the field - in the short-term experimental exposures of P. grandis, metal detoxification was less effective than in chronically exposed native bivalves.

Impact of seawater carbonate chemistry on the calcification of marine bivalves

OpenAIRE

Thomsen Jörn; Haynert Kristin; Wegner K Mathias; Melzner Frank

2015-01-01

Bivalve calcification, particular of the early larval stages is highly sensitive to the change of ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32−] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the e...

Reproductive investment in the intertidal bivalve Macoma balthica

Science.gov (United States)

Honkoop, P. J. C.; Van der Meer, J.; Beukema, J. J.; Kwast, D.

1999-05-01

Bivalve eggs generally contain large amounts of lipids which, in comparison with proteins and carbohydrates, have high energy contents and are thus costly in energetic terms. As lipid contents vary between species, comparisons of reproductive investments should not only include numbers and sizes of eggs, but also their energy content. We estimated the investment in egg material of mature females of the Baltic tellin Macoma balthica (L.) in terms of both mass and energy content. All mass below a minimum body mass (below which no eggs are produced) was defined as structural mass. This threshold amounts to a body mass index (BMI) of 5.6 (ash-free dry mass per cubic shell length in mg cm -3). More than half (55%) of the mass above the structural mass was invested in egg material and 45% in extra somatic tissue and tissue for production and storage of gametes. This means that the amount of eggs spawned ranged from 0 (at BMI = 5.6 mg cm -3) to 33% of the total ash-free dry mass (at a high BMI value of 14 mg cm -3). Eggs contained a relatively large amount of lipids, about 30% of their ash-free dry mass, whereas non-egg material contained only about 7% lipids. Eggs of two other bivalves in the Wadden Sea, the cockle Cerastoderma edule and the mussel Mytilus edulis, were smaller and contained only about 11% and 20% lipids, respectively. Energy content of M. balthica eggs amounted to ˜0.006 J, in the other two species to ˜0.002 J. The function of the more expensive eggs in M. balthica may be related to its early spawning in spring, causing slower larval development until first feeding.

Predation on intertidal mussels: Influence of biotic factors on the survival of epibenthic bivalve beds

NARCIS (Netherlands)

Waser, A.M.

2018-01-01

Coastal areas are amongst the most productive ecosystems in the world. Important components of these coastal areas are reef-forming bivalves such as mussels and oysters, as they have important facilitating effects on many associated organisms through the provision of substratum,

Le contrôle de gestion des entreprises familiales : un contrôle non-financiarisé ?

OpenAIRE

Barbelivien , Dominique

2016-01-01

Nous examinons la tendance décrite dans la littérature quant à la financiarisation de la fonction de contrôle de gestion en nous appuyant sur le cas d’une entreprise de taille intermédiaire familiale. Nous constatons que le contrôle de gestion dans le cas étudié correspond à une rationalisation des décisions opérationnelles et développons les raisons qui peuvent expliquer la persistance d’un contrôle de gestion très opérationnel. Le contexte d’entreprise familiale dans laquelle il y a confusi...

Sodium provides unique insights into transgenerational effects of ocean acidification on bivalve shell formation.

Science.gov (United States)

Zhao, Liqiang; Schöne, Bernd R; Mertz-Kraus, Regina; Yang, Feng

2017-01-15

Ocean acidification is likely to have profound impacts on marine bivalves, especially on their early life stages. Therefore, it is imperative to know whether and to what extent bivalves will be able to acclimate or adapt to an acidifying ocean over multiple generations. Here, we show that reduced seawater pH projected for the end of this century (i.e., pH7.7) led to a significant decrease of shell production of newly settled juvenile Manila clams, Ruditapes philippinarum. However, juveniles from parents exposed to low pH grew significantly faster than those from parents grown at ambient pH, exhibiting a rapid transgenerational acclimation to an acidic environment. The sodium composition of the shells may shed new light on the mechanisms responsible for beneficial transgenerational acclimation. Irrespective of parental exposure, the amount of Na incorporated into shells increased with decreasing pH, implying active removal of excessive protons through the Na + /H + exchanger which is known to depend on the Na + gradient actively built up by the Na + /K + -ATPase as a driving force. However, the shells with a prior history of transgenerational exposure to low pH recorded significantly lower amounts of Na than those with no history of acidic exposure. It therefore seems very likely that the clams may implement less costly and more ATP-efficient ion regulatory mechanisms to maintain pH homeostasis in the calcifying fluid following transgenerational acclimation. Our results suggest that marine bivalves may have a greater capacity to acclimate or adapt to ocean acidification by the end of this century than currently understood. Copyright © 2016 Elsevier B.V. All rights reserved.

An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

NARCIS (Netherlands)

Cranford, P.J.; Kamermans, P.; Krause, G.H.M.; Mazurie, J.

2012-01-01

An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and

Evaluation of the threat of marine CO{sub 2} leakage-associated acidification on the toxicity of sediment metals to juvenile bivalves

Energy Technology Data Exchange (ETDEWEB)

Basallote, M. Dolores, E-mail: dolores.basallote@uca.es [Cátedra UNESCO/UNITWIN WiCop, Departamento de Química-Física, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Polígono Río San Pedro s/n, 11510 Puerto Real, Cádiz (Spain); Rodríguez-Romero, Araceli [Departamento de Ecología y Gestión Costera, Instituto de Ciencias Marinas de Andalucía (CSIC), Campus Río San Pedro, 11510 Puerto Real, Cádiz (Spain); De Orte, Manoela R.; Del Valls, T. Ángel; Riba, Inmaculada [Cátedra UNESCO/UNITWIN WiCop, Departamento de Química-Física, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, Polígono Río San Pedro s/n, 11510 Puerto Real, Cádiz (Spain)

2015-09-15

Highlights: • Short-term tests using juveniles of bivalves to study the effects of CO{sub 2} dissolved. • CO{sub 2} causes effects if the threshold concentration of the organism is overlapped. • Flows of escaped CO{sub 2} would affect the geochemical composition of sediment–seawater. • CO{sub 2}-induced acidification would affect differently to marine sediment toxicity. - Abstract: The effects of the acidification associated with CO{sub 2} leakage from sub-seabed geological storage was studied by the evaluation of the short-term effects of CO{sub 2}-induced acidification on juveniles of the bivalve Ruditapes philippinarum. Laboratory scale experiments were performed using a CO{sub 2}-bubbling system designed to conduct ecotoxicological assays. The organisms were exposed for 10 days to elutriates of sediments collected in different littoral areas that were subjected to various pH treatments (pH 7.1, 6.6, 6.1). The acute pH-associated effects on the bivalves were observed, and the dissolved metals in the elutriates were measured. The median toxic effect pH was calculated, which ranged from 6.33 to 6.45. The amount of dissolved Zn in the sediment elutriates increased in parallel with the pH reductions and was correlated with the proton concentrations. The pH, the pCO{sub 2} and the dissolved metal concentrations (Zn and Fe) were linked with the mortality of the exposed bivalves.

Element availability of bivalve with symbiotic zooxanthellae in coral sea area as studied by multielement profiling analysis

Science.gov (United States)

Itoh, A.; Kabe, N.

2008-12-01

In coral sea, a characteristic ecosystem is formed by many kinds of marine animals and plants, although seawater is uneutrophic. This may be explained by the fact that various chemical species with bioessentiality are effectively taken and used by lower animals and plants in coral sea area. A symbiotic relationship often found among different animals and plants in this area is considered to be working as one of such processes. However, the specific bioavailability of the elements for the marine animals and plants in coral reef area has not been studied from the viewpoints of trace and ultratrace elements. It is found by the present authors that bivalve with symbiotic zooxanthellae (Tridacna crocea) living on coral reef had relatively higher bio- accumulation factors for many bio-essential elements than other kinds of bivalves, although they live in the uneutrophic sea area. The present authors focused on Tridacna crocea as one of the symbiotic animals. Thus, in the present study, at first, multielement determination of major-to-ultratrace elements (about 20 elements) in each organ of Tridacna crocea with symbiotic zooxanthellae, were carried out by ICP-AES, ICP- MS, and CHN coder. At Second, the specific bioavailability of trace and ultratrace elements in Tridacna crocea was discussed on the multielement data for seawater, seaweeds, and other bivalves in coral sea area.

Abundance, biomass and caloric content of Chukchi Sea bivalves and association with Pacific walrus (Odobenus rosmarus divergens) relative density and distribution in the northeastern Chukchi Sea

Science.gov (United States)

Young, Jordann K.; Black, Bryan A.; Clarke, Janet T.; Schonberg, Susan V.; Dunton, Kenneth H.

2017-10-01

The northeastern Chukchi Sea is a shallow subarctic shelf ecosystem that supports a substantial benthic infaunal community of which bivalves are a major component. We assessed the patterns in population abundance, biomass, and caloric content of ten dominant bivalve taxa in relation to the distribution of the upper trophic level consumer Pacific walrus (Odobenus rosmarus divergens). Bivalves were collected over four cruises in the northeastern Chukchi Sea (2009, 2010, 2012, 2013). Our samples were largely dominated by calorie-dense, deposit-feeding species, including Macoma spp., Ennucula tenuis, Nuculana spp. and Yoldia spp. Weight-frequency distributions were strongly right-skewed for most taxa, though some showed evidence of a bimodal distribution. Caloric densities as measured through bomb calorimetry significantly differed among taxa (ANOVA F = 32.57, df = 9, p-valueanimal wet weight was found to be a reliable predictor of whole animal caloric content. Bivalve populations and peak caloric densities were centered on and to the southeast of Hanna Shoal, which coincided with peak Pacific walrus relative density (walruses per km surveyed) from July through October. Significant differences in mean caloric values were found between areas with and without walruses present (student's t-test, t=-2.9088, df = 252.24, p-value = 0.003952), as well as between areas with low and high walrus relative densities in the pooled annual dataset and in each individual month except October (ANOVA, p-value<0.05). The high-calorie deposit feeders that dominate these bivalve communities preferentially consume food sources, such as sea ice algae, that are likely to be affected by shifting sea ice dynamics. As such, continued warming has the potential to alter bivalve communities in the northeastern Chukchi Sea, which may have profound implications for upper trophic levels.

Contamination of raw bivalve molluscs available in Poland between 2009 and 2013 with marine biotoxins

Directory of Open Access Journals (Sweden)

Michalski Mirosław

2016-12-01

Full Text Available Introduction: Growing consumption of shellfish is associated with an increased risk of food poisoning. The study was carried out on live bivalve molluscs available on the Polish market between 2009 and 2013. Material and Methods: ELISA was used for the determination of the following marine biotoxins: paralytic shellfish poison (PSP, amnaesic shellfish poison (ASP, and diarrhoeic shellfish poison (DSP. The molluscs, of which seven species were examined, were obtained from wholesale companies and markets. Results: Marine biotoxins were detected below the permitted levels in 67.6% of the samples. The maximum amounts of PSP and ASP biotoxins were found in great scallops (532.6 μg/kg and 1.0 mg/kg respectively and the peak for DSP was in blue mussels (107 μg/kg. Conclusion: The analysis of toxicological status of raw bivalve molluscs available on the market in Poland indicates that they are safe for consumers.

Plio-Pleistocene extinctions and immigration credit reflected in the size-frequency distribution of Mediterranean marine bivalves

Science.gov (United States)

Nawrot, Rafal; Zuschin, Martin; Chattopadhyay, Devapriya

2015-04-01

Following the opening of the Suez Canal hundreds of Red Sea species have entered the Mediterranean Sea making it a global hot spot of marine bioinvasion. With the ongoing influx of the subtropical and tropical alien species and increasing sea surface temperatures, the Mediterranean biota is currently gaining a more tropical character and increasingly becoming a mixture of faunal stocks with different evolutionary histories. This susceptibility to invasion was suggested to reflect the presence of an empty ecological space left after decimation of incumbent warm-water fauna during Plio-Pleistocene climate fluctuations. As molluscs are among the most prolific immigrants, we test this hypothesis using data on taxonomic composition and body size of Pliocene Mediterranean bivalves derived from the literature sources and museum collections. The Pliocene inter-specific size-frequency distribution (SFD) is strikingly similar to the SFDs of the Recent Red Sea bivalve fauna, in spite of different biogeographic provenance and the absence of true reef ecosystems in the Pliocene of the Mediterranean region. In contrast, body-size patterns in both assemblages are significantly different from the present-day Mediterranean fauna characterized by smaller median and modal size. Our preliminary results suggest that the distinct shape of the modern Mediterranean SFD may reflect the selective nature of the late Piacenzian - Galesian (Late Pliocene - Early Pleistocene) extinctions pulses related to the onset of the Northern Hemisphere glaciations. These extinctions affected almost 40% of Pliocene species and were biased towards large-bodied taxa. They were not followed by re-immigration of warm-water species owing to the isolation from the tropical Atlantic biota by the cold upwelling along the NW coasts of Africa. The resulting invasion credit (sensu Jackson & Sax, 2010) is currently being paid by the Red Sea bivalves colonizing the Mediterranean Sea through the Suez Canal. Successful

Light and scanning electron microscopic studies of Unionicola tetrafurcatus (Acari: Unionicolidae) infecting four freshwater bivalve species with referring to histopathological effect on its hosts.

Science.gov (United States)

Abdel-Gaber, Rewaida; Fol, Mona; Al Quraishy, Saleh

2018-05-08

Water mites of the genus Unionicola are the most common symbionts of freshwater bivalves. During the current investigation, a total of 120 live freshwater mussels [Corbicula fluminea (Veneroida), Coelatura aegyptiaca (Unionoidea) Mutela rostrata and Chambardia rubens (Mutelidae)], were collected from 2 localities in Tura (Helwan Governorate) and El Kanater (Qaluobiya Governorate), Egypt. Only 3 of the 4 bivalve species listed are considered freshwater bivalves (members of Unionoidea). While, C. fluminea belong to the family Cyrenidae within Veneroida. The collected mussels were dissected and examined for the presence of unionicolid mites. It was found that 30.83% (37/120) were infected with a single mite species Unionicola tetrafurcatus (Unionicolidae). The highest prevalence was observed during the summer with 83.33% (25/30), whereas the least was observed in autumn, i.e. 33.33% (10/30). Mites were recovered from the gills, gonads, and visceral mass of mussel hosts. gills of host mussels were the primary site of oviposition for unionicola mites. Smaller bivalves in size had significantly greater numbers of mites than larger ones in size. Numbers of mites per host species was variable and the highest prevalence level of 83.33% (25/30) was recorded in C. fluminea, while, the lowest one of 16.66% (5/30) was found in C. rubens. Morphological and morphometric characterizations of mites revealed some differences between the present species and other related Unionicola. Histopathological responses of host mussels to the eggs, larvae, and cuticular remnants of U. tetrafurcatus were also studied. Therefore, the present study demonstrated that freshwater bivalves have a new host and locality records for infection with U. tetrafurcatus. Future studies are recommended to include advanced molecular characteristics for these mites.

Le pompage optique naturel dans le milieu astrophysique

Science.gov (United States)

Pecker, J.-C.

The title of this lecture abstracts only a part of it : the importance in astrophysics of the study of non-LTE situations has become considerable, as well in the stellar atmospheres as, still more, in the study of fortuitous coincidences as a mechanism of formation of emission line nebular spectra, or of molecular interstellar « masers ». Another part of this talk underlines the role of Kastler in his time, and describes his warm personality through his public reactions in front of the nuclear armement, of the Viet-Nam and Algerian wars, of the problems of political refugees... Kastler was a great scientist ; he was also a courageous humanist. 1976 : Les accords nucléaires du Brésil : allocution d'ouverture (19 mars). Colloque sur le sujet ci-dessus. 1976 : La promotion de la culture dans le nouvel ordre économique international, allocution à l'occasion d'une table ronde sur ce thème par l'UNESCO (23-27 juin 1976) ; « Sciences et Techniques », octobre 1976. 1979 : La bête immonde (avec J.-C. Pecker), « Le Matin », 20 mars. 1979 : Appel à nos ministres (avec J.-C. Pecker), « Le Monde », 13 décembre. 1979 : Le flou, le ténébreux, l'irrationnel (avec J.-C. Pecker), « Le Monde », 14 septembre. 1980 : Education à la paix, Préface, in : Publ. UNESCO. 1981 : Le vrai danger, « Le Monde », 6 août 1981. 1982 : Nucléaire civil et militaire, « Le Monde », 1er juin 1982. 1982 : Les scientifiques face à la perspective d'holocauste nucléaire (texte inédit). Le titre de cette communication en résume seulement une partie : l'importance prise en astrophysique par l'analyse des situations hors ETL est devenue considérable, qu'il s'agisse des atmosphères stellaires, ou plus encore, des coïncidences fortuites de la formation des spectres d'émission nébulaires, ou des « masers » moléculaires interstellaires. Une autre partie de cet exposé souligne le rôle de Kastler dans son époque, et décrit sa personnalité généreuse à travers ses r

Uniform Variation in Genetic-Traits of a Marine Bivalve Related to Starvation, Pollution and Geographic Clines

NARCIS (Netherlands)

Hummel, H.; Bogaards, R.H.; Amiard-Triquet, C.; Bachelet, G.; Desprez, M.; Marchand, J.; Rybarczyk, H.; Sylvand, B.; De Wit, Y.; De Wolf, L.

1995-01-01

Consistent patterns of genetic variation in the marine bivalve Macoma balthica (L.) were found after exposure to low levels of copper, starvation, and along geographic dines. The geographic dines were related to temperature and salinity. Genetic differences were primarily found in the LAP (Leucine

Mobile Element Evolution Playing Jigsaw - SINEs in Gastropod and Bivalve Mollusks.

Science.gov (United States)

Matetovici, Irina; Sajgo, Szilard; Ianc, Bianca; Ochis, Cornelia; Bulzu, Paul; Popescu, Octavian; Damert, Annette

2016-01-06

SINEs (Short INterspersed Elements) are widely distributed among eukaryotes. Some SINE families are organized in superfamilies characterized by a shared central domain. These central domains are conserved across species, classes, and even phyla. Here we report the identification of two novel such superfamilies in the genomes of gastropod and bivalve mollusks. The central conserved domain of the first superfamily is present in SINEs in Caenogastropoda and Vetigastropoda as well as in all four subclasses of Bivalvia. We designated the domain MESC (Romanian for MElc-snail and SCoica-mussel) because it appears to be restricted to snails and mussels. The second superfamily is restricted to Caenogastropoda. Its central conserved domain-Snail-is related to the Nin-DC domain. Furthermore, we provide evidence that a 40-bp subdomain of the SINE V-domain is conserved in SINEs in mollusks and arthropods. It is predicted to form a stable stem-loop structure that is preserved in the context of the overall SINE RNA secondary structure in invertebrates. Our analysis also recovered short retrotransposons with a Long INterspersed Element (LINE)-derived 5' end. These share the body and/or the tail with transfer RNA (tRNA)-derived SINEs within and across species. Finally, we identified CORE SINEs in gastropods and bivalves-extending the distribution range of this superfamily. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Le contrôle de gestion environnementale d'une entreprise

OpenAIRE

Marquet-Pondeville, Sophie

2001-01-01

Dans cette recherche, nous étudions comment s’opère le contrôle de gestion environnementale. Cette problématique est abordée dans une perspective contingente et nous proposons un modèle théorique qui met en évidence l’impact de certaines variables sur les systèmes de contrôle de la gestion environnementale. Certains liens présents dans ce modèle sont discutés à travers une étude de cas.

Biomonitoring of Heavy metals using the bivalve molluscs in sunderban mangrove wetland, Northeast Coast of Bay of bengal (india): possible risks to Human health

Energy Technology Data Exchange (ETDEWEB)

Cabral, Henrique; Cardoso, Ines [Departamento de Biologia Animal/Instituto de Oceanografia, Campo Grande, Lisboa (Portugal); Chatterjee, Mousumi; Kumar Bhattacharya, Asok; Aftab Alam, Mohammad [Department of Marine Science, University of Calcutta, Calcutta (India); Kanta Satpathy, Kamala [Indira Gandhi Centre for Atomic Research, Environmental and Industrial Safety Section, Safety Group, Kalpakkam, Tamil Nadu (India); Kumar Sarkar, Santosh

2008-02-15

The suitability of using four bivalve molluscs (Sanguinolaria acuminata, Anadara granosa, Meretrix meretrix, and Pelecyora trigona) in biomonitoring of heavy metals (Cu, Pb, Cd, Zn, and Hg) collected from intertidal regions of the Sunderban mangrove wetland, northeastern part of the Bay of Bengal, were evaluated. Both speciesdependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in the bivalves where gill and mantle exhibited higher metal accumulation due to ion exchange property of the mucous layer covering these organs while shells represent very poor accumulation. Elevated values of Zn and Cu reflect high potential for biomagnification through marine food chain. Metal concentrations in different body size groups of the bivalves do not follow uniform trend. Correlation coefficient between different metal couplings as tested statistically revealed significant coupling for Pb-Zn, Pb-Cu, Zn-Cu, and Hg-Cu. Concentrations of all the metals in specific organs (visceral mass, mantle and gill) of the bivalves exceeded the safe levels according to the international standards for metals compiled by Food and Agricultural Organization of the United Nations and would be of great risk for human consumption. It is concluded that the mussel and clam are suitable biomonitors to employ in programs designed to assess changes in metal pollution in the Sunderban mangrove wetland. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

Microplastics in bivalves cultured for human consumption.

Science.gov (United States)

Van Cauwenberghe, Lisbeth; Janssen, Colin R

2014-10-01

Microplastics are present throughout the marine environment and ingestion of these plastic particles (microplastics in two species of commercially grown bivalves: Mytilus edulis and Crassostrea gigas. Microplastics were recovered from the soft tissues of both species. At time of human consumption, M. edulis contains on average 0.36 ± 0.07 particles g(-1) (wet weight), while a plastic load of 0.47 ± 0.16 particles g(-1) ww was detected in C. gigas. As a result, the annual dietary exposure for European shellfish consumers can amount to 11,000 microplastics per year. The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estimating microplastic toxicity, estimations of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible. Copyright © 2014 Elsevier Ltd. All rights reserved.

Boreholes on three bivalve species found on the sand beach at Sagot Cape, Baengnyeongdo, Korea

Directory of Open Access Journals (Sweden)

Dal-Yong Kong

2017-12-01

Full Text Available Circular to subcircular boreholes were found on the surfaces of three different bivalve shells (Mactra chinensis, Felaniella usta, and Nuttallia japonica that were pushed onto the sand beach at Sagot Cape, Baengnyeongdo, Korea. The boreholes are characterized by beveled holes that are parabolic in cross section. The boreholes are classified into the ichnospecies Oichnus paraboloides, probably drilled by a naticid gastropod Glossaulax didyma didyma living in the Baengnyeong tidal flat. In the case of Mactrashells, boreholes are observed more or less evenly on left and right valves, and 96% of boreholes are located on the umbo. This may suggest that the life position of the Baengnyeong bivalves did not dictate the preference of G. didyma didyma in the Baengnyeong tidal flat ecosystem. The clustered distribution of the boreholes in the umbo area indicates a strong site selectivity for boreholes that is quite a common phenomenon in many naticid gastropods. Keywords: Baengnyeongdo, Mactra chinensis, Naticid gastropods, Oichnus paraboloides, Prey–predator interactions

Le rôle des intervenants non gouvernementaux dans le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Ce projet servira à déterminer les facteurs stratégiques et réglementaires qui ont contribué ou nui aux efforts visant à permettre aux fournisseurs non gouvernementaux de participer au renforcement des systèmes de santé. Le rôle des fournisseurs de ... Climate Change and Water Adaptation Options. The impacts of climate ...

Metals and organotins in multiple bivalve species in a one-off global survey

DEFF Research Database (Denmark)

Larsen, Martin Mørk; Strand, Jakob; Christensen, Jan H.

2011-01-01

contamination levels on a global scale. Metal concentrations in nine bivalve species were normalised to the Mytilidae family using conversion factors based on cosampled species and literature bioconcentration factors. The lowest metal and tributyltin concentrations were below background assessment...... were low, but not always lower than expected impacted areas. The most contaminated areas were harbours, where especially Copenhagen, St Croix and Sydney, can be considered hotspots of tributyltin as well as a number of metals....

Some effects of temperature and starvation on the bivalve @iDonax vittatus@@ (da Costa) in experimental laboratory populations

Digital Repository Service at National Institute of Oceanography (India)

Ansell, A.D.; Sivadas, P.

The effect of temperature on the body weight and composition, and on respiration, filtration and NH, excretion of the bivalve Donax uittatus (da Costa) has been investigated in laboratory-maintained populations under conditions of starvation In all...

Ways of uptake for a freshwater bivalve of radiostrontium and its loss (Anodonta cygnea (L)); Modaites de la contamination d'un bivalve d'eau douce par le radiostrontium et de sa decontamination - Anodonta cygnea (L)

Energy Technology Data Exchange (ETDEWEB)

Cancio, D; Foulquier, L; Grauby, A [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1968-07-01

The authors summarize general notions concerning ecological characteristics of Anodonta cygnea, commonly found in the hydrological system of the Rhone river. Experimental conditions allowing to follow the evolution of the animal's activity level are described. In general, the amount of radiostrontium retained by these organisms is low as compared to the existing activity in the aquaria (2 to 9 pour cent); after 35 days, a state of equilibrium is reached. The shell retains more than 50 per cent of the animal activity by adsorption mechanisms. The gills show a fixation capacity higher than the rest of the other organs. The concentration factor is about 9 for the entire animal, 4 for the shell and 78 for whole of the soft - tissues. The presence or absence of sediment has no influence on the accumulation process and the fixation capacity of the organisms. The absence of light decreases the concentration factor, this is due probably to a reduction of the contamination through micro-organisms. The decontamination does not follow a simple law; a rapid loss in the activity (T 1/2 {approx_equal} 8 days) is followed by a slower elimination (T 1/2 {approx_equal} 72 days). Independent on the type of experiment, the distribution of the activity in the organisms was similar, i.e. the shell represents almost 45 per cent of the animal activity, the soft tissues 40 per cent and the inner liquids 15 per cent. (authors) [French] Les auteurs donnent des notions generales concernant les caracteristiques ecologiques d'Anodonta cygnea tres repandue dans le Bassin Rhodanien. Ils indiquent les conditions experimentales ayant permis de suivre l'evolution de l'activite des animaux. D'une maniere generale la quantite de radiostrontium fixee par les organismes est faible par rapport a l'activite introduite dans le bac (2 a 9 pour cent). On obtient un etat d'equilibre au bout de 35 jours environ; la coquille, par des mecanismes d'adsorption, peut retenir plus de 50 pour cent de l'activite de l

Le stéréotype dans le roman policier

Directory of Open Access Journals (Sweden)

Marion François

2009-12-01

Full Text Available Le roman policier offre à l’étude du stéréotype une grande variété de redondances, lexicales et structurelles, qui permettent d’éclairer le concept même de genre, en fait issu du constat de stéréotypie. Il est également manifeste que contrairement aux idées reçues, les clichés font du texte policier un texte littéraire, parce qu’ils naissent d’images associées, distinctes de la réalité, qui révèlent d’ailleurs le cheminement même de l’écriture. Par ailleurs ces images jouent un rôle fondamental dans le plaisir du lecteur, comme dans les contes de fées de notre enfance. Les clichés ouvrent la porte des fantasmes : le stéréotype rejoignant l’archétype, les clichés policiers réactivent de nombreux mythes, le texte évoquant l’Autre Scène. Le constat de stéréotypie provoque l’écriture, en particulier parodique, et stimule le renouvellement et l’essaimage des clichés dans toutes sortes de textes, qui bénéficieront de la présence du déjà-lu, laquelle donne au lecteur une assise pour affronter l’inconnu et une expérience pour apprécier la nouveauté.

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Le CRDI et la lutte contre le paludisme | CRDI - Centre de ...

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22 juil. 2011 ... D'autres interventions luttent également contre le paludisme, notamment les moustiquaires imprégnées d'insecticide et les médicaments visant à prévenir le ... Le CRDI appuie le GCRAI depuis les années 1970 et participe avec SIMA au financement de la recherche sur les interactions complexes entre ...

Le livre sur le livre traité de documentation

CERN Document Server

Otlet, Paul

2015-01-01

Paul Otlet est considéré comme le père des sciences de l'information. Ouvrage fondateur et fondamental, le Traité de documentation. Le livre sur le livre (1934) est l'aboutissement de son travail inlassable pour rassembler, classer et partager les connaissances. Otlet y propose une remarquable synthèse du savoir sur le livre et le document en même temps qu'il anticipe Internet et l'hypertexte. La réédition du Traité de documentation, 70 ans après la disparition de son auteur, coïncide avec la réouverture du Mundaneum à Mons, où le fabuleux héritage documentaire légué par Paul Otlet et Henri La Fontaine est conservé. « Ici, la table de travail n'est plus chargée d'aucun livre. À leur place se dresse un écran et à portée un téléphone. Là-bas, au loin, dans un édifice immense, sont tous les livres et tous les renseignements. De là, on fait apparaître sur l'écran la page à lire pour connaître la réponse aux questions posées par téléphone. » Préfaces de Benoît Peeters (éc...

Uptake and metabolism of 14C-chloropyrifos by marine bivalves

International Nuclear Information System (INIS)

Zhong, C.G.; Chen, S.; Zhao, X.; Shi, J.; Carvalho, F.P.

1999-01-01

The uptake and metabolism of 14 C-chlorpyrifos by two marine bivalves, Paphia undulata and Sinonovacula constricta, were studied in a simulated ecosystem. The experiments were carried out in two 30 L glass tanks containing each 20 L of filtered sea water, contaminated with 14 C-chlorpyrifos 1.85x10 4 Bq.L -1 (16.7 μg.L -1 ) at the beginning of the exposure period. At different time intervals, three specimens of each species were sampled for analysis of the pesticide in the molluscs tissues. The 14 C-chlorpyrifos residues were extracted from the digestive gland of the molluscs and analyzed by co-chromatography with pesticide standards by TLC methods described before

Trace element determination in soft tissues of marine bivalves by activation analysis

International Nuclear Information System (INIS)

Fukushima, M.; Tamate, H.; Nakano, Y.

2003-01-01

Trace elements in soft tissues of marine bivalves were determined by neutron activation analysis (NAA) and photon activation analysis (PAA). Elemental levels of Ag, As, Br, Co, Cu, Fe, I, Mn, Ni, Rb, Se, and Zn in the organs of giant ezoscallos, rock oysters, and giant crams were obtained. The metal-bound proteins were extracted from the mantles and hepatopancreases of rock oysters. By irradiating the fraction obtained by HPLC gel chromatography, the possibility for the existence of an Ag bound protein in the mantles was found. (author)

Cephalic and limb anatomy of a new Isoxyid from the Burgess Shale and the role of "stem bivalved arthropods" in the disparity of the frontalmost appendage.

Directory of Open Access Journals (Sweden)

Cédric Aria

Full Text Available We herein describe Surusicaris elegans gen. et sp. nov. (in Isoxyidae, amended, a middle (Series 3, Stage 5 Cambrian bivalved arthropod from the new Burgess Shale deposit of Marble Canyon (Kootenay National Park, British Columbia. Surusicaris exhibits 12 simple, partly undivided biramous trunk limbs with long tripartite caeca, which may illustrate a plesiomorphic "fused" condition of exopod and endopod. We construe also that the head is made of five somites (= four segments, including two eyes, one pair of anomalocaridid-like frontalmost appendages, and three pairs of poorly sclerotized uniramous limbs. This fossil may therefore be a candidate for illustrating the origin of the plesiomorphic head condition in euarthropods, and questions the significance of the "two-segmented head" in, e.g., fuxianhuiids. The frontalmost appendage in isoxyids is intriguingly disparate, bearing similarities with both dinocaridids and euarthropods. In order to evaluate the relative importance of bivalved arthropods, such as Surusicaris, in the hypothetical structuro-functional transition between the dinocaridid frontal appendage and the pre-oral-arguably deutocerebral-appendage of euarthropods, we chose a phenetic approach and computed morphospace occupancy for the frontalmost appendages of 36 stem and crown taxa. Results show different levels of evolutionary decoupling between frontalmost appendage disparity and body plans. Variance is greatest in dinocaridids and "stem bivalved" arthropods, but these groups do not occupy the morphospace homogeneously. Rather, the diversity of frontalmost appendages in "stem bivalved" arthropods, distinct in its absence of clear clustering, is found to link the morphologies of "short great appendages," chelicerae and antennules. This find fits the hypothesis of an increase in disparity of the deutocerebral appendage prior to its diversification in euarthropods, and possibly corresponds to its original time of development. The

Cephalic and limb anatomy of a new Isoxyid from the Burgess Shale and the role of "stem bivalved arthropods" in the disparity of the frontalmost appendage.

Science.gov (United States)

Aria, Cédric; Caron, Jean-Bernard

2015-01-01

We herein describe Surusicaris elegans gen. et sp. nov. (in Isoxyidae, amended), a middle (Series 3, Stage 5) Cambrian bivalved arthropod from the new Burgess Shale deposit of Marble Canyon (Kootenay National Park, British Columbia). Surusicaris exhibits 12 simple, partly undivided biramous trunk limbs with long tripartite caeca, which may illustrate a plesiomorphic "fused" condition of exopod and endopod. We construe also that the head is made of five somites (= four segments), including two eyes, one pair of anomalocaridid-like frontalmost appendages, and three pairs of poorly sclerotized uniramous limbs. This fossil may therefore be a candidate for illustrating the origin of the plesiomorphic head condition in euarthropods, and questions the significance of the "two-segmented head" in, e.g., fuxianhuiids. The frontalmost appendage in isoxyids is intriguingly disparate, bearing similarities with both dinocaridids and euarthropods. In order to evaluate the relative importance of bivalved arthropods, such as Surusicaris, in the hypothetical structuro-functional transition between the dinocaridid frontal appendage and the pre-oral-arguably deutocerebral-appendage of euarthropods, we chose a phenetic approach and computed morphospace occupancy for the frontalmost appendages of 36 stem and crown taxa. Results show different levels of evolutionary decoupling between frontalmost appendage disparity and body plans. Variance is greatest in dinocaridids and "stem bivalved" arthropods, but these groups do not occupy the morphospace homogeneously. Rather, the diversity of frontalmost appendages in "stem bivalved" arthropods, distinct in its absence of clear clustering, is found to link the morphologies of "short great appendages," chelicerae and antennules. This find fits the hypothesis of an increase in disparity of the deutocerebral appendage prior to its diversification in euarthropods, and possibly corresponds to its original time of development. The analysis of this

Accumulation of butyl- and phenyltin compounds in starfish and bivalves from the coastal environment of Korea

Energy Technology Data Exchange (ETDEWEB)

Shim, Won Joon [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of)]. E-mail: wjshim@kordi.re.kr; Yim, Un Hyuk [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Kim, Nam Sook [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Hong, Sang Hee [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Oh, Jae Ryoung [Southern Coastal Environment Research Division, Korea Ocean Research and Development Institute, Jangmok-myon 391, Geoje 656-830 (Korea, Republic of); Jeon, Joong Kyun [Department of Marine Bioscience and Technology, Kangnung National University, Kangnung 210-702 (Korea, Republic of); Okamura, Hideo [Laboratory of Marine Environment Management, Kobe University Mercantile Marine, Fukaeminami 5-1-1, Highshinada, Kobe 658-0022 (Japan)

2005-02-01

Triphenyltin (TPT) and tributyltin (TBT) concentrations were determined in two starfish species (Asteria pectinifera and Asterias amurensis), bivalves (Crassostrea gigas or Mytilus edulis), and seawater samples from sites around the coasts of Korea. Both TPT and TBT concentrations in starfish ranged from 8 to 1560 ng/g and from <2 to 797 ng/g as Sn on a dry weight basis, respectively. TPT concentration accounted for 75.4% and 86.4% of total phenyltin concentration in A. pectinifera and A. amurensis, respectively, while monobutyltin, a degradation product of TBT, accounted for 86.3% and 57.2% of total butyltin, respectively. Triphenyltin concentrations in A. pectinifera were significantly correlated to water and bivalve TPT concentrations, which implies that dietary uptake of TPT from contaminated prey as well as direct uptake from surrounding water contribute to TPT body residues in the starfish. Starfish could be target organisms for monitoring TPT compound in the marine environment, due to their high accumulation and low degradation capacity towards TPT. - Starfish are effective organisms for monitoring phenyltin contamination in the marine environment.

Accumulation of butyl- and phenyltin compounds in starfish and bivalves from the coastal environment of Korea

International Nuclear Information System (INIS)

Shim, Won Joon; Yim, Un Hyuk; Kim, Nam Sook; Hong, Sang Hee; Oh, Jae Ryoung; Jeon, Joong Kyun; Okamura, Hideo

2005-01-01

Triphenyltin (TPT) and tributyltin (TBT) concentrations were determined in two starfish species (Asteria pectinifera and Asterias amurensis), bivalves (Crassostrea gigas or Mytilus edulis), and seawater samples from sites around the coasts of Korea. Both TPT and TBT concentrations in starfish ranged from 8 to 1560 ng/g and from <2 to 797 ng/g as Sn on a dry weight basis, respectively. TPT concentration accounted for 75.4% and 86.4% of total phenyltin concentration in A. pectinifera and A. amurensis, respectively, while monobutyltin, a degradation product of TBT, accounted for 86.3% and 57.2% of total butyltin, respectively. Triphenyltin concentrations in A. pectinifera were significantly correlated to water and bivalve TPT concentrations, which implies that dietary uptake of TPT from contaminated prey as well as direct uptake from surrounding water contribute to TPT body residues in the starfish. Starfish could be target organisms for monitoring TPT compound in the marine environment, due to their high accumulation and low degradation capacity towards TPT. - Starfish are effective organisms for monitoring phenyltin contamination in the marine environment

Optimal designs of mollusk shells from bivalves to snails.

Science.gov (United States)

Okabe, Takuya; Yoshimura, Jin

2017-02-10

Bivalve, ammonite and snail shells are described by a small number of geometrical parameters. Raup noted that the vast majority of theoretically possible shell forms do not occur in nature. The constraint factors that regulate the biased distribution of natural form have long since been an open problem in evolution. The problem of whether natural shell form is a result of optimization remains unsolved despite previous attempts. Here we solve this problem by considering the scaling exponent of shell thickness as a morphological parameter. The scaling exponent has a drastic effect on the optimal design of shell shapes. The observed characteristic shapes of natural shells are explained in a unified manner as a result of optimal utilization of shell material resources, while isometric growth in thickness leads to impossibly tight coiling.

Assessing phototoxicity of petroleum using the bivalve Mulinia lateralis and the mysid Mysidopsis bahia

International Nuclear Information System (INIS)

Pelletier, M.; Champlin, D.; Burgess, R.; Ho, K.; Kuhn-Hines, A.

1995-01-01

One of the major inputs of PAHs in the marine environment is petroleum products. A large and often catastrophic source of petroleum is an oil spill, which releases concentrated quantities of PAHs into the water column. Intermediate molecular weight compounds remain in the water column for a relatively extended length of time. These compounds include phototoxic PAHs such as anthracene, fluoranthene, pyrene, and their substituted derivatives. Assessments of the environmental impact of marine oil spills have not included phototoxicity tests using pelagic larvae of benthic invertebrates. In this study, the photoreactive toxicity of individual PAHs, including anthracene, pyrene, and fluoranthene, were determined using the bivalve, Mulinia lateralis and the mysid, Mysidopsis bahia. Ultraviolet light exposures increased toxicity relative to fluorescent light for both species but a particularly dramatic response was seen using M. lateralis embryos. This species was relatively insensitive when exposed under fluorescent lights, but exhibited up to a 4,000 fold increase in toxicity under ultraviolet lights. Exposures with different types of petroleum (e.g., fuel oil number-sign 2 and crude oil) under fluorescent and ultraviolet light will demonstrate the utility of this bivalve and mysid for assessing oil spill-related acute and sublethal toxicity in the marine environment

L’Association du personnel, le TREF, le Comité des Finances et le Conseil du CERN

CERN Multimedia

Staff Association

2016-01-01

L’Association du personnel, forte de son approche participative et consensuelle, recherche toujours le meilleur accord possible pour l’Organisation et son personnel. Pour ce faire, discussions et concertation avec la Direction, travail d’explication et de persuasion au TREF et ailleurs auprès des délégués des États membres sont nos principaux atouts. TREF (Tripartite Employment Conditions Forum), un Forum d’échanges, de discussions « L’objectif du Forum est d’améliorer le processus de prise de décision  en donnant aux personnes concernées la possibilité et le temps de comprendre pleinement la position de tous les participants. » (CERN/RTG/8) Le Forum tripartite sur les conditions d’emploi (TREF), créé par le Conseil du CERN en juin 1994, est composé de r...

INVESTIR DANS LE SAVOIR : le soutien que le CRDI consent à des ...

International Development Research Centre (IDRC) Digital Library (Canada)

5 nov. 2010 ... ... 40 ans, le Cenre de recherches pour le développement international (CRDI), en plus d'appuyer des travaux de recherche dans l'ensemble des pays en développement, encourage des générations successives de jeunes chercheurs par l'entremise de son Programme de formation et de bourses (PFB).

Le nouveau modèle africain | IDRC - International Development ...

International Development Research Centre (IDRC) Digital Library (Canada)

22 juil. 2011 ... L'annulation de la dette, un commerce plus équitable, davantage d'aide : voilà le plan d'action mondial dont on convient qu'il faut de toute urgence mettre en oeuvre en vue d'accélérer le développement en Afrique. Or, ce serait rater le bateau que de ne pas s'engager dans la voie tout autre que les ...

La lipogenèse chez le lapin. Importance pour le contrôle de la teneur en lipides de la viande

OpenAIRE

Gondret, Florence

1999-01-01

La teneur en lipides d’un tissu est la résultante de plusieurs flux métaboliques (dépôt, synthèse, utilisation). Cet article présente les principales caractéristiques de la synthèse des lipides chez le lapin, dans le muscle comparativement aux tissus adipeux visibles et au foie. Le potentiel de synthèse de novo exprimé par le muscle augmente avec l’âge de l’animal, en parallèle à l’accumulation des triglycérides dans les adipocytes intramusculaires. L’activité des enzymes qui fournissent le N...

Rapport financier trimestriel pour le trimestre qui a pris fin le 31

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31 déc. 2015 ... Le CRDI finance des travaux de recherche appliquée ... recherches pour le développement international (CRDI, le Centre) et ..... voie de développement et sur la mise en oeuvre des connaissances scientifiques, techniques et autres en .... Les accords expirent à des dates différentes, et le dernier prend fin.

Rapport financier trimestriel pour le trimestre qui a pris fin le 30

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30 sept. 2015 ... Le CRDI finance des travaux de recherche appliquée ... recherches pour le développement international (le Centre) et de ..... voie de développement et sur la mise en oeuvre des connaissances scientifiques, techniques et autres en .... Les accords expirent à des dates différentes, et le dernier prend fin en.

Le modèle spatial de la capitale allemande

Directory of Open Access Journals (Sweden)

Antoine Laporte

2013-06-01

Full Text Available En Allemagne, en 1999, le Chancelier fédéral et son gouvernement ont quitté Bonn pour Berlin. Ce transfert du pouvoir est accompagné de celui d’une grande partie de l’appareil d’État et de la haute administration, et des fonctions qui leur sont traditionnellement attribuées comme la presse, les lobbys ou encore la diplomatie. Le déplacement du statut de capitale effective de l’Allemagne de Bonn à Berlin est le résultat des évolutions géopolitiques d’un pays ayant recouvré son unité et sa pleine et entière souveraineté. Installer le pouvoir exécutif et législatif à Berlin était une démarche hautement symbolique, visant à normaliser la position de l’ancienne capitale de la RDA et du IIIe Reich comme véritable centre politique de l’Allemagne. Or le déplacement des institutions fédérales n’est pas qu’un acte symbolique. Il entraîne également à l’échelle intra-urbaine des dynamiques très concrètes sur le tissu urbain et participe à la mise en place de nouvelles centralités dans la ville. En effet, le statut de capitale d’État prédestine l’agglomération à la coprésence de nombreuses fonctions urbaines spécifiques plus ou moins directement liées à l’exercice ou à la symbolique du pouvoir.

The quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) – another Ponto-Caspian dreissenid bivalve in the southern Baltic catchment: the first record from the Szczecin Lagoon

OpenAIRE

Adam Woźniczka; Brygida Wawrzyniak-Wydrowska; Teresa Radziejewska; Anna Skrzypacz

2016-01-01

In 2014, a non-indigenous dreissenid bivalve, the quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) was for the first time recorded in the Szczecin Lagoon. This was also the first record of the species in the Baltic Sea catchment. The quagga mussel was found to accompany the zebra mussel (Dreissena polymorpha), a non-indigenous bivalve already firmly established in the Lagoon. As indicated by the new immigrant's estimated abundance (4000.0 ± 355.44 ind. m−2) and the zebra mussel ...

Les femmes dans le secteur du travail domestique et le secteur ...

International Development Research Centre (IDRC) Digital Library (Canada)

Ce projet vise à rectifier le tir en faisant la lumière sur les caractéristiques ... le secteur du travail domestique et dans le secteur bancaire modifient la nature du travail ... des sciences sociales, des sciences humaines, de la santé publique ou.

Le Conseil des gouverneurs | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le Conseil des gouverneurs guide le travail du CRDI en lui fournissant une orientation stratégique, en examinant ses activités et en approuvant ses budgets. Les gouverneurs – un maximum de 14 – sont nommés par le gouverneur en conseil du Canada pour un mandat d'au plus quatre ans, qui peut être reconduit. La Loi ...

Le FIVB annonce le financement de cinq autres projets | CRDI ...

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10 avr. 2018 ... En partenariat avec la Fondation Bill et Melinda Gates et Affaires mondiales Canada, le CRDI est heureux d'annoncer la prochaine série de projets soutenus par le Fonds d'innovation en matière de vaccins pour le bétail (FIVB). À ce jour, 11 projets ont obtenu un financement total de 13,6 millions de CAD ...

Soundscapes and Larval Settlement: Larval Bivalve Responses to Habitat-Associated Underwater Sounds.

Science.gov (United States)

Eggleston, David B; Lillis, Ashlee; Bohnenstiehl, DelWayne R

2016-01-01

We quantified the effects of habitat-associated sounds on the settlement response of two species of bivalves with contrasting habitat preferences: (1) Crassostrea virginicia (oyster), which prefers to settle on other oysters, and (2) Mercenaria mercenaria (clam), which settles on unstructured habitats. Oyster larval settlement in the laboratory was significantly higher when exposed to oyster reef sound compared with either off-reef or no-sound treatments. Clam larval settlement did not vary according to sound treatments. Similar to laboratory results, field experiments showed that oyster larval settlement in "larval housings" suspended above oyster reefs was significantly higher compared with off-reef sites.

An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

OpenAIRE

Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche; Mazurie, Joseph; Buck, Bela H.; Dolmer, Per; Fraser, David; Van Nieuwenhove, Kris; O'Beirn, Francis X.; Sanchez-mata, Adoracion; Thorarinsdottir, Gudrun G.; Strand, Oivind

2012-01-01

An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–en...

Démocratie et le développement dans le monde arabe | IDRC ...

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Le Rapport sur le développement humain dans le monde arabe 2002 souligne un " déficit en matière de libertés " fondamental dans le monde arabe se traduisant dans toute la région par des régimes autoritaires et la faiblesse de la démocratie. Cette subvention permettra aux chercheurs Samir Makdisi et Ibrahim Elbadawi ...

Ways of uptake for a freshwater bivalve of radiostrontium and its loss (Anodonta cygnea (L)); Modaites de la contamination d'un bivalve d'eau douce par le radiostrontium et de sa decontamination - Anodonta cygnea (L)

Energy Technology Data Exchange (ETDEWEB)

Cancio, D.; Foulquier, L.; Grauby, A. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1968-07-01

The authors summarize general notions concerning ecological characteristics of Anodonta cygnea, commonly found in the hydrological system of the Rhone river. Experimental conditions allowing to follow the evolution of the animal's activity level are described. In general, the amount of radiostrontium retained by these organisms is low as compared to the existing activity in the aquaria (2 to 9 pour cent); after 35 days, a state of equilibrium is reached. The shell retains more than 50 per cent of the animal activity by adsorption mechanisms. The gills show a fixation capacity higher than the rest of the other organs. The concentration factor is about 9 for the entire animal, 4 for the shell and 78 for whole of the soft - tissues. The presence or absence of sediment has no influence on the accumulation process and the fixation capacity of the organisms. The absence of light decreases the concentration factor, this is due probably to a reduction of the contamination through micro-organisms. The decontamination does not follow a simple law; a rapid loss in the activity (T 1/2 {approx_equal} 8 days) is followed by a slower elimination (T 1/2 {approx_equal} 72 days). Independent on the type of experiment, the distribution of the activity in the organisms was similar, i.e. the shell represents almost 45 per cent of the animal activity, the soft tissues 40 per cent and the inner liquids 15 per cent. (authors) [French] Les auteurs donnent des notions generales concernant les caracteristiques ecologiques d'Anodonta cygnea tres repandue dans le Bassin Rhodanien. Ils indiquent les conditions experimentales ayant permis de suivre l'evolution de l'activite des animaux. D'une maniere generale la quantite de radiostrontium fixee par les organismes est faible par rapport a l'activite introduite dans le bac (2 a 9 pour cent). On obtient un etat d'equilibre au bout de 35 jours environ; la coquille, par des mecanismes d'adsorption, peut retenir

Le nouveau modèle africain | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

22 juil. 2011 ... Or, ce serait rater le bateau que de ne pas s'engager dans la voie tout autre que les Africains proposent maintenant — à savoir se défaire du syndrome de la dépendance qui afflige l'Afrique depuis des décennies. Le Canada et les autres pays riches du Nord reconnaissent généralement qu'ils ne peuvent ...

Sensitivity of Mediterranean bivalve mollusc aquaculture to climate change, ocean acidification, and other environmental pressures: findings from a producers’ survey

NARCIS (Netherlands)

Rodrigues, L.; van den Bergh, J.C.J.M.; Mass, F.; Theodorou, J.A.; Ziveri, P.; Gazeau, F.

2015-01-01

Human-induced climate change and ocean acidification are global environmental phenomena with a common driver: anthropogenic emissions of carbon dioxide. Both processes potentially threaten the Mediterranean bivalve mollusc aquaculture sector, which is economically relevant to several regions and

Le facteur humain et la sûreté de fonctionnement dans le ...

African Journals Online (AJOL)

Notre contribution porte sur le rôle fondamental du facteur humain dans le management intégré des risques d'une part et du rôle déterminant qu'il peut avoir à jouer pour que la sûreté de fonctionnement réponde à sa propriété d'autre part. Un rôle illustré à travers une analyse de risque dans un complexe de Gaz Naturel ...

Carbon and nitrogen elemental and isotopic ratios of filter-feeding bivalves along the French coasts: An assessment of specific, geographic, seasonal and multi-decadal variations.

Science.gov (United States)

Briant, Nicolas; Savoye, Nicolas; Chouvelon, Tiphaine; David, Valérie; Rodriguez, Samuel; Charlier, Karine; Sonke, Jeroen E; Chiffoleau, Jean François; Brach-Papa, Christophe; Knoery, Joël

2018-02-01

Primary consumers play a key role in coastal ecosystems by transferring organic matter from primary producers to predators. Among them, suspension-feeders, like bivalve molluscs are widely used in trophic web studies. The main goal of this study was to investigate variations of C and N elemental and isotopic ratios in common bivalves (M. edulis, M. galloprovincialis, and C. gigas) at large spatial (i.e. among three coastal regions) and different temporal (i.e. from seasonal to multi-decadal) scales in France, in order to identify potential general or specific patterns and speculate on their drivers. The observed spatial variability was related to the trophic status of the coastal regions (oligotrophic Mediterranean Sea versus meso- to eutrophic English Channel and Atlantic ocean), but not to ecosystem typology (estuaries, versus lagoons versus bays versus littoral systems). Furthermore, it highlighted local specificities in terms of the origin of the POM assimilated by bivalves (e.g., mainly continental POM vs. marine phytoplankton vs. microphytobenthic algae). Likewise, seasonal variability was related both to the reproduction cycle for C/N ratios of Mytilus spp. and to changes in trophic resources for δ 13 C of species located close to river mouth. Multi-decadal evolution exhibited shifts and trends for part of the 30-year series with decreases in δ 13 C and δ 15 N. Specifically, shifts appeared in the early 2000's, likely linking bivalve isotopic ratios to a cascade of processes affected by local drivers. Copyright © 2017 Elsevier B.V. All rights reserved.

Le corps sportif1

OpenAIRE

Brulé, Pierre

2015-01-01

Le nu et le cuit Si, pas plus que l’Auvergne, le monde grec antique n’a été le théâtre d’un quelconque « miracle », il n’a pas manqué, toutefois, de « distinctions » diverses, d’exceptions même, qui le singularisent absolument. Une, c’est la pédérastie. Quelle culture l’a autant valorisée, autant instrumentalisée, l’a autant érigée en modèle ? Nous n’en avons pas encore mesuré toutes les conséquences. La place inhabituelle que prend là et alors cette polyvalence rare de la libido masculine de...

Influence of a step-change in metal exposure (Cd, Cu, Zn) on metal accumulation and subcellular partitioning in a freshwater bivalve, Pyganodon grandis: A long-term transplantation experiment between lakes with contrasting ambient metal levels

Energy Technology Data Exchange (ETDEWEB)

Cooper, Sophie [INRS-Eau, Terre et Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bonneris, Emmanuelle [INRS-Eau, Terre et Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9 (Canada) and Bayer S.A.S., Bayer CropScience, 16 Rue Jean-Marie Leclair, CP 90106, F 69266 Lyon Cedex 09 (France); Michaud, Annick [INRS-Eau, Terre et Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9 (Canada) and Direction des Évaluations environnementales, Ministère du Développement durable, de l’Environnement et des Parcs, 675, boul. René-Lévesque Est, 6e étage, Québec, QC G1R 5V7 (Canada); Pinel-Alloul, Bernadette [Groupe de Recherche Interuniversitaire en Limnologie et Environnement Aquatique (GRIL), Département de Sciences Biologiques, Université de Montréal, C.P. 6128, Montréal, QC H3C 3J7 (Canada); Campbell, Peter G.C., E-mail: peter.campbell@ete.inrs.ca [INRS-Eau, Terre et Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9 (Canada)

2013-05-15

Highlights: ? We transferred freshwater bivalves from a reference lake to a Cd and Zn contaminated lake. ? Changes in metal accumulation and subcellular partitioning were followed over time (up to 860 d). ? Metal detoxification strategies differed between target organs (gills vs. digestive gland). ? The ability to handle Cd is inherent in P. grandis, not a trait acquired after long-term adaptation. -- Abstract: The objective of the present field experiment was to identify detoxification responses in the gills and digestive gland of a freshwater unionid bivalve, Pyganodon grandis, subjected to a step-change in metal exposure. Adult bivalves were transferred from a reference site (Lake Opasatica) and a metal-contaminated lake (Lake Héva) to a second contaminated lake (Lake Vaudray) in northwestern Quebec, Canada. Changes in organ metal concentrations, in the subcellular distribution of metals and in metallothionein concentrations were followed over time (t = 0, 132, (400) and 860 days). At each collection time and for each bivalve, the gills and digestive gland were excised and gently homogenized; six sub-cellular fractions were separated by differential centrifugation and analyzed for their Cd, Cu and Zn content, and metallothionein was quantified independently. Metal detoxification strategies were shown to differ between target organs: in the gills, incoming metals were sequestered largely in the granules, whereas in the digestive gland the same metals primarily accumulated in the cytosol, in the metallothionein-like protein fraction. These metal-handling strategies, as employed by the metal-naïve bivalves originating in the reference lake, closely resemble those identified in free-living P. grandis chronically exposed in the metal-contaminated lake, suggesting that the ability to handle incoming metals (Cd in particular) is inherent in P. grandis and is not a trait acquired after long-term adaptation of the bivalve to metal-contaminated environments. The

Hyperloop : le droit et le devoir de douter...

OpenAIRE

Crozet , Yves

2016-01-01

National audience; C’est comme si c’était fait ! Les journaux les plus sérieux (Les Echos) nous annoncent que le premier test du prototype Hyperloop dans le désert du Nevada est un succès. Le projet futuriste d’Elon Musk se concrétise. Un véhicule terrestre de transport collectif va bientôt se déplacer à plus de 1000 km/h entre San Francisco et Los Angeles. Comme pour donner du crédit à cette information, la SNCF, via sa filiale SYSTRA va devenir partenaire du projet. Déjà les journaux de Pro...

LE LIEN ENTRE FINANCE ET ECONOMIE ISLAMIQUES VIA LE MODELE PRINCIPIEL "ZR"

OpenAIRE

BELABES, ABDERRAZAK

2010-01-01

A l'heure où certains évoquent l'intégration de la finance islamique à la finance globale, et d'autres rattachent la finance islamique à des thèmes en vogue telles que la finance éthique, la finance participative ou la finance socialement responsable, le présent papier explore le lien entre finance et économie islamiques à partir du modèle principiel "ZR", c’est-à-dire "Zakât" et "Ribâ". Ce modèle montre que les principes invariants de Zakât et Ribâ jouent un rôle central dans l’établissement...

Le Kenya nomme le titulaire de sa première chaire de recherche

International Development Research Centre (IDRC) Digital Library (Canada)

14 avr. 2016 ... De concert avec le CRDI, la National Commission for Science, Technology and Innovation (NACOSTI) du Kenya a inauguré sa première chaire de recherche à Nairobi, le 31 mars 2015. Le professeur Fabian Omoding Esamai, qui dirige actuellement le College of Health Sciences de la Moi University, a été ...

pour le trimestre qui a pris fin le 31 décembre 2014

International Development Research Centre (IDRC) Digital Library (Canada)

Office 2004 Test Drive User

31 déc. 2014 ... Le CRDI finance des travaux de recherche appliquée ... recherches pour le développement international (le Centre) et de ...... voie de développement et sur la mise en oeuvre des connaissances scientifiques, techniques et autres en vue .... Les accords expirent à des dates différentes, et le dernier prend fin.

Le cru, le cuit et le pourri dans _Le vice-consul_ de Marguerite Duras

Directory of Open Access Journals (Sweden)

Hélène Caron

2011-05-01

Full Text Available Bien que plusieurs articles critiques aient déjà avancé de nouvelles perspectives sur le texte Le Vice-Consul (LVC de Marguerite Duras, l’analyse de la représentation de la nourriture dans ce roman n’a fait l’objet d’aucune étude. Cet article tente donc de combler cette lacune en proposant d’analyser les images du cru et du cuit, images qui se rejoignent sous les notions du pourri et de l’abject, tout en offrant quelques interprétations de l’un des passages critiques du roman où la folle mendiante croque la tête d’un poisson vivant.

Subcellular compartmentalization of Cd and Zn in two bivalves. II. Significance of trophically available metal (TAM)

Science.gov (United States)

Wallace, W.G.; Luoma, S.N.

2003-01-01

This paper examines how the subcellular partitioning of Cd and Zn in the bivalves Macoma balthica and Potamocorbula amurensis may affect the trophic transfer of metal to predators. Results show that the partitioning of metals to organelles, 'enzymes' and metallothioneins (MT) comprise a subcellular compartment containing trophically available metal (TAM; i.e. metal trophically available to predators), and that because this partitioning varies with species, animal size and metal, TAM is similarly influenced. Clams from San Francisco Bay, California, were exposed for 14 d to 3.5 ??g 1-1 Cd and 20.5 ??g 1-1 Zn, including 109Cd and 65Zn as radiotracers, and were used in feeding experiments with grass shrimp Palaemon macrodatylus, or used to investigate the subcellular partitioning of metal. Grass shrimp fed Cd-contaminated P. amurensis absorbed ???60% of ingested Cd, which was in accordance with the partitioning of Cd to the bivalve's TAM compartment (i.e. Cd associated with organelles, 'enzymes' and MT); a similar relationship was found in previous studies with grass shrimp fed Cd-contaminated oligochaetes. Thus, TAM may be used as a tool to predict the trophic transfer of at least Cd. Subcellular fractionation revealed that ???34% of both the Cd and Zn accumulated by M. balthica was associated with TAM, while partitioning to TAM in P. amurensis was metal-dependent (???60% for TAM-Cd%, ???73% for TAM-Zn%). The greater TAM-Cd% of P. amurensis than M. balthica is due to preferential binding of Cd to MT and 'enzymes', while enhanced TAM-Zn% of P. amurensis results from a greater binding of Zn to organelles. TAM for most species-metal combinations was size-dependent, decreasing with increased clam size. Based on field data, it is estimated that of the 2 bivalves, P. amurensis poses the greater threat of Cd exposure to predators because of higher tissue concentrations and greater partitioning as TAM; exposure of Zn to predators would be similar between these species.

Immunomodulation by different types of N-oxides in the hemocytes of the marine bivalve Mytilus galloprovincialis.

Directory of Open Access Journals (Sweden)

Caterina Ciacci

Full Text Available The potential toxicity of engineered nanoparticles (NPs for humans and the environment represents an emerging issue. Since the aquatic environment represents the ultimate sink for NP deposition, the development of suitable assays is needed to evaluate the potential impact of NPs on aquatic biota. The immune system is a sensitive target for NPs, and conservation of innate immunity represents an useful basis for studying common biological responses to NPs. Suspension-feeding invertebrates, such as bivalves, are particularly at risk to NP exposure, since they have extremely developed systems for uptake of nano and microscale particles integral to intracellular digestion and cellular immunity. Evaluation of the effects of NPs on functional parameters of bivalve immunocytes, the hemocytes, may help understanding the major toxic mechanisms and modes of actions that could be relevant for different NP types in aquatic organisms.In this work, a battery of assays was applied to the hemocytes of the marine bivalve Mytilus galloprovincialis to compare the in vitro effects of different n-oxides (n-TiO(2, n-SiO(2, n-ZnO, n-CeO(2 chosen on the basis of their commercial and environmental relevance. Physico-chemical characterization of both primary particles and NP suspensions in artificial sea water-ASW was performed. Hemocyte lysosomal and mitochondrial parameters, oxyradical and nitric oxide production, phagocytic activity, as well as NP uptake, were evaluated. The results show that different n-oxides rapidly elicited differential responses hemocytes in relation to their chemical properties, concentration, behavior in sea water, and interactions with subcellular compartments. These represent the most extensive data so far available on the effects of NPs in the cells of aquatic organisms. The results indicate that Mytilus hemocytes can be utilized as a suitable model for screening the potential effects of NPs in the cells of aquatic invertebrates, and may

Le Peer to Peer: Vers un Nouveau Modèle de Civilization

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Michel Bauwens

2006-06-01

Full Text Available Le « peer to peer » est la dynamique intersubjective caractéristique des réseaux distribués. Le but de cet essai est de montrer qu'il s'agit d'une véritable nouvelle forme d’organisation sociale, apte à produire et échanger des biens, à créer de la valeur. Celle-ci est la conséquence d'un nouvel imaginaire social, et possède le potentiel de devenir le pilier d'un nouveau mode d'économie politique, voire d'un nouveau type de civilisation. Pour cela, nous allons d'abord définir le P2P, décrire en bref ces manifestations, et le différencier d'autres modalités d'échange intersubjectif tel que le marché, la hiérarchie, l'économie du don.Comme principale modalité P2P nous distinguons: Les processus de production P2P, comme troisième mode de production, qui n'est ni géré par un mode hiérarchique ou par l'état, ni répondant à des impératifs de profit ou qui sont modulés par le biais des prix. Les processus de gouvernance P2P, qui gouverne ces processus de production. Les formes de propriété P2P, qui sont destine a empecher l’appropriation prive de cette production pour le commun.Afin d’examiner les characteristiques de cette nouvelle dynamique sociale, nous utilisons la typologie intersubjective de l’anthropologue Alan Page Fisque, qui distingue: 1. l'échange égalitaire (Equality Matching, c..a.d l’economie du don. 2. La relation d’autorité (Authority Ranking tel qu’elle s’exprime dans le mode hierarchique. 3. le marché (Market Pricing. 4. la participation commune (Communal Shareholding.En conclusion, nous examinons les possibilites d’expansion de ce nouveau mode sociale et son insertion dans l’economie capitaliste, en nous nous posons la question: le P2P peut-il etre concu comme alternative sociale et economique aux modeles existants.

Le « modèle germanique » Français

OpenAIRE

Lefebvre , Armelle

2009-01-01

Resume Le concept d?Allemagne permet de reveler, selon une approche , l?ampleur des desaccords ayant preside a la definition du concept d?Etat en France. De ce dernier, l?on aborde divers emplois qu?illustrent des modeles d?Etat. Le opere ainsi dans un debat qui est le creuset de la connaissance politique moderne, avec ses apories: celles de la souverainete externe, de l?ordre interetatique, de la confederation. L?article expose alo...

Systematics, functional morphology and distribution of a bivalve (Apachecorbula muriatica gen. et sp. nov.) from the rim of the 'Valdivia Deep' brine pool in the Red Sea

KAUST Repository

Oliver, Pere Graham

2014-11-11

The deep brine pools of the Red Sea comprise extreme, inhospitable habitats yet house microbial communities that potentially may fuel adjacent fauna. We here describe a novel bivalve from a deep-sea (1525 m) brine pool in the Red Sea, where conditions of high salinity, lowered pH, partial anoxia and high temperatures are prevalent. Remotely operated vehicle (ROV) footage showed that the bivalves were present in a narrow (20 cm) band along the rim of the brine pool, suggesting that it is not only tolerant of such extreme conditions but is also limited to them. The bivalve is a member of the Corbulidae and named Apachecorbula muriatica gen. et sp. nov. The shell is atypical of the family in being modioliform and thin. The semi-infaunal habit is seen in ROV images and reflected in the anatomy by the lack of siphons. The ctenidia are large and typical of a suspension feeding bivalve, but the absence of \\'guard cilia\\' and the greatly reduced labial palps suggest that it is non-selective as a response to low food availability. It is proposed that the low body mass observed is a consequence of the extreme habitat and low food availability. It is postulated that the observed morphology of Apachecorbula is a result of paedomorphosis driven by the effects of the extreme environment on growth but is in part mitigated by the absence of high predation pressures. © Marine Biological Association of the United Kingdom, 2014.

Using transplanted bivalves to assess oil exposure and effects in Delaware Bay

International Nuclear Information System (INIS)

Salazar, M.; Salazar, S.; Mearns, A.; Venosa, A.; Eberhart, B.

1995-01-01

To evaluate the effectiveness of bioremediation, the US EPA oiled intertidal plots in Delaware Bay and monitored oil degradation rates. This controlled release of oil was also used to test the utility of transplanted bivalves in assessing oil spills and to evaluate the extent and potential effects of the release. Measuring the accumulation of oil in bivalve tissues was used to estimate exposure and the extent of contamination. Growth was used to estimate potential bioeffects. Approximately 1,800 mussels and 1,200 oysters were transplanted to 11 intertidal sites. Five treatment sites were within 1 meter of the lower end of the oiled plots. A total of six sites were used as controls, three on either side of the oiled plots at 5, 10, and 100 m. Samples were taken on Day 0, 2, 15, and 28 to estimate the rate of bioaccumulation. All of the mussels died within the first week of exposure; oysters exhibited over 95% survival but growth was minimal. The authors found a statistically significant difference in tissue weights when comparing treatment sites with control sites. The total concentration of polynuclear aromatic hydrocarbons (PAHs) in tissues of oysters nearest the oiled plots increased by a factor of four after an exposure period of two days. PAH concentrations in control oysters nearest the mouth of the bay increased slightly but the differences were not statistically significant. The control oysters nearest the head of the bay received an intermediate dose which was depurated by the end of the 28-day experiment. PAHs in the oysters nearest the oiled plots approached but did not return to background levels by the end of the test

Los Dioramas de Le Corbusier = Le Corbusier's Dioramas

Directory of Open Access Journals (Sweden)

José Ramón Alonso Pereira

2013-10-01

Full Text Available ResumenLe Corbusier simboliza el urbanismo moderno racional, cuyo esfuerzo riguroso de planificación exige un esfuerzo paralelo de comprensión. Se opone a ese urbanismo contemporáneo que quiere percibir y disfrutar la ciudad sensiblemente. Sentimiento y razón, sin embargo, no son opuestos y Le Corbusier nos dio en su momento las claves para intentar una síntesis, uniéndolos de modo singular por medio de sus ‘boîte à miracles’ o ‘cajas mágicas’: esos "espectáculos arquitectónicos de síntesis" que definiría en el Ciam de 1951. Pretendemos aproximarnos aquí a la primera de esos ‘espectáculos’: el ‘diorama’, viéndolo como estrategia corbuseriana de mediación entre lo racional y lo sensible en la ciudad moderna y contemporánea.Palabras claveLe Corbusier, diorama, Ville Contemporaine, Plan Voisin, Plan MaciáAbstractLe Corbusier symbolizes the modern rational urbanism, whose rigorous effort of town planning demands a parallel effort of comprehension. It opposes to these contemporary urbanism that wish to perceive and to enjoy cities in a sensible way. Nevertheless, sentiment and reason are not adverses and Le Corbusier gives us at his  moment keys to intent a synthesis, joined them in a singular way by means of his ‘boîtes à miracles’ or ‘magic boxes’: those "architectural spectacles of synthesis" that he defined in 1951 Ciam. Here we try to approach to the first of those ‘spectacles’: the ‘diorama’, considering it as a corbusean strategy of mediation between rational and sensible in modern and contemporary city.Key wordsLe Corbusier, diorama, Ville Contemporaine, Plan Voisin, Plan Maciá.

Rapport financier trimestriel pour le trimestre qui a pris fin le 30

International Development Research Centre (IDRC) Digital Library (Canada)

Sophie Comeau

30 sept. 2011 ... politiques, de chercheurs et de collectivités de par le monde. ..... Financement : le CRDI est visé par l'Examen stratégique et ... Le Conseil des gouverneurs a amorcé la planification du recrutement du nouveau président.

Occurrence of potentially pathogenic Vibrio in oysters (Crassostrea gigas) and waters from bivalve mollusk cultivations in the South Bay of Santa Catarina.

Science.gov (United States)

Ramos, Roberta Juliano; Miotto, Letícia Adélia; Miotto, Marília; Silveira Junior, Nelson; Cirolini, Andréia; Silva, Helen Silvestre da; Rodrigues, Dália dos Prazeres; Vieira, Cleide Rosana Werneck

2014-01-01

This research aimed to identify and quantify potentially pathogenic Vibrio from different cultivations of bivalve shellfish in the State of Santa Catarina, Brazil, and water regions in the South Bay, as well as correlate the incidence of these microorganisms with the physicochemical parameters of marine waters. Between October 2008 and March 2009, 60 oyster and seawater samples were collected from six regions of bivalve mollusk cultivation, and these samples were submitted for Vibrio counts. Twenty-nine (48.3%) oyster samples were revealed to be contaminated with one or more Vibrio species. The Vibrio parahaemolyticus and Vibrio vulnificus counts in the samples ranged from oyster and from oyster, respectively. Of the 60 seawater samples analyzed, 44 (73.3%) showed signs of contamination with one or more vibrio species. The counts of V. parahaemolyticus and V. vulnificus in the samples ranged from < 0.3 log10 MPN·100mL(-1) to 1.7 log10MPN·100mL(-1) seawater and from < 0.3 log10 MPN·100mL(-1) to 2.0 log10 MPN·100mL(-1) seawater, respectively. A positive correlation between V. vulnificus counts and the seawater temperature as well as a negative correlation between the V. parahaemolyticus counts and salinity were observed. The results suggest the need to implement strategies to prevent vibrio diseases from being transmitted by the consumption of contaminated bivalve shellfish.

Le Sanskrit

CERN Document Server

Balbir, Nalini

2013-01-01

Cet ouvrage est destiné à tous ceux qui souhaitent se mettre ou se remettre à l'étude du sanskrit et ne peuvent y consacrer que quelques minutes par jour. En suivant le principe de la méthode quotidienne Assimil, vous acquerrez progressivement le vocabulaire et la grammaire de base qui sont nécessaires à la lecture des textes de la littérature sanskrite classique. Vous trouverez dans cette méthode une approche vivante de la langue et de la culture sanskrite classique à travers des textes d'abord adaptés pour le débutant puis authentiques. En quelques mois, vous manierez la langue sans efforts ni hésitation, de manière très naturelle. Les enregistrements reprennent l'intégralité des textes en sanskrit des leçons et des exercices de traduction du livre. Ils sont interprétés, à un rythme progressif, par des locuteurs natifs professionnels.

Respiration of bivalves from three different deep-sea areas: Cold seeps, hydrothermal vents and organic carbon-rich sediments

Science.gov (United States)

Khripounoff, A.; Caprais, J. C.; Decker, C.; Le Bruchec, J.; Noel, P.; Husson, B.

2017-08-01

We studied bivalves (vesicomyids and mytilids) inhabiting four different areas of high sulfide and methane production: (1) in the Gulf of Guinea, two pockmarks (650 m and 3150 m depth) and one site rich in organic sediments in the deepest zone (4950 m average depth), (2) at the Azores Triple Junction on the Mid-Atlantic Ridge, one hydrothermal site (Lucky Strike vent field, 1700 m depth). Two types of Calmar benthic chambers were deployed, either directly set into the sediment (standard Calmar chamber) or fitted with a tank to isolate organisms from the sediment (modified Calmar chamber), to assess gas and solute exchanges in relation to bivalve bed metabolism. Fluxes of oxygen, total carbon dioxide, ammonium and methane were measured. At the site with organic-rich sediments, oxygen consumption by clams measured in situ with the standard benthic chamber was variable (1.3-6.7 mmol m-2 h-1) as was total carbon dioxide production (1-9.6 mmol m-2 h-1). The observed gas and solute fluxes were attributed primarily to bivalve respiration (vesicomyids or mytilids), but microbial and geochemical processes in the sediment may be also responsible for some of variations in the deepest stations. The respiration rate of isolated vesicomyids (16.1-0.25.7 μmol g-1 dry weight h-1) was always lower than that of mytilids (33 μmol g-1 dry weight h-1). This difference was attributed to the presence of a commensal scaleworm in the mytilids. The respiratory coefficient (QR) ≥1 indicated high levels of anaerobic metabolism. The O:N index ranged from 5 to 25, confirming that vesicomyids and mytilids, living in symbiosis with bacteria, have a protein-based food diet.

Estimation of food limitation of bivalve larvae in coastal waters of north-western Europe

DEFF Research Database (Denmark)

Bos, O.G.; Hendriks, I.E.; Strasser, M.

2006-01-01

Marine invertebrate recruitment may be affected by food limitation during the pelagic larval life stages. In the present study, field data on abundance of bivalve larvae along with their prey (small phytoplankton) were examined to see whether they were consistent with predictions made...... assimilation rate averaged 7-26% of the maximum assimilation rate. Under the assumptions made for the present study, it is suggested that growth of larvae in north-west European waters is often food-limited. (c) 2005 Elsevier B.V. All rights reserved...

PAH assessment in the main Brazilian offshore oil and gas production area using semi-permeable membrane devices (SPMD) and transplanted bivalves

Science.gov (United States)

André Lourenço, Rafael; Francisco de Oliveira, Fábio; Haddad Nudi, Adriana; Rebello Wagener, Ângela de Luca; Guadalupe Meniconi, Maria de Fátima; Francioni, Eleine

2015-06-01

The Campos Basin is Brazil's main oil and gas production area. In 2013, more than 50 million cubic meters of produced water (PW) was discharged into these offshore waters. Despite the large volumes of PW that are discharged in the Campos Basin each day, the ecological concern of the chemicals in the PW are not completely understood. Polycyclic aromatic hydrocarbons (PAH) are the most important contributors to the ecological hazards that are posed by discharged PW. This study aimed to evaluate the potential bioaccumulation of PAH using transplanted bivalves (Nodipecten nodosus) and semi-permeable membrane devices (SPMD). The study was conducted in two platforms that discharge PW (P19 and P40). Another platform that does not discharge PW (P25) was investigated for comparison with the obtained results. Time-integrated hydrocarbon concentrations using SPMD and transplanted bivalves were estimated from the seawater near the three platforms. The bioaccumulation of the PAH in the transplanted bivalves at platforms P19 and P40 were up to fivefold greater than the bioaccumulation of the PAH at platform P25. The lowest PAH concentrations were estimated for platform P25 (4.3-6.2 ng L-1), and the highest PAH concentrations were estimated for platform P19 (9.2-37.3 ng L-1). Both techniques were effective for determining the bioavailability of the PAH and for providing time-integrated hydrocarbon concentrations regarding oil and gas production activities.

De quoi le genre est-il le nom ?

OpenAIRE

Andrieu, Bernard

2013-01-01

Cette note de lecture présente une courte évolution des travaux sur le genre sous l’angle du rapport au corps en démontrant comment la dénaturalisation du corps et du sexe biologique a conduit à une description culturaliste des fonctions individuelles et des rôles sociaux. Si le genre dénaturalise le corps c’est en refusant toute référence au sexe ou à la sexualité en tant qu’ils seraient des données naturelles. Depuis son apparition en 1947, sous la plume de John Money, psychologue chargé du...

Le modèle fédéral dans le sport français, un principe fondateur dépassé ?

Directory of Open Access Journals (Sweden)

Béatrice Barbusse

2009-06-01

Full Text Available Dans le sport français, le fédéralisme s’est installé comme une évidence institutionnelle dès la fin du 19e siècle et le début du 20e siècle dans un pays qui pourtant ne se pense pas fédéral. En outre, si son apparition est liée à l’émergence du sport comme nouvelle pratique sociale à côté d’autres pratiques physiques plus traditionnelles, il s’est rapidement imposé comme la pierre angulaire de l’ordre sportif français. Près d’un siècle plus tard, son monopole institutionnel est bousculé voire «concurrencé». Ces constats d’ensemble nous amènent à nous interroger sur les raisons pour lesquelles le sport a épousé le modèle fédéral dans un pays non fédéral, mais aussi sur ses limites actuelles. Est-il encore le modèle approprié aux circonstances contemporaines ? A-t-il toujours sa place dans le système de gouvernance du sport ? Ou bien, a contrario, reste-t-il le dernier rempart légitime face aux excès du sport contemporain (dopage, violence, corruptions, déficits… ? À partir d’une approche socio-historique, il s’est agi dans cet article de reconstruire le fil de la généalogie du fédéralisme sportif tout en s’interrogeant sur ses perspectives. Au delà de la question du fédéralisme, c’est bien celle de la gouvernance du sport contemporain qui est posée.

Alkylphenols and polycyclic aromatic hydrocarbons in bivalves from Comunidad Valenciana coastal waters; Alquilfenoles e hidrocarburos aromaticos policiclicos en bivalvos de las coastas de la comunidad Valenciana

Energy Technology Data Exchange (ETDEWEB)

Marti Ortega, N.; Aguado Garcia, D.; Bouzas Blanco, A.; Segovia Martinez, L.; Albargues Llamas, M.; Sevillano Cabeza, A.; Campins Falco, P.; Seco Torrecillas, A.; Ferrer Polo, J.

2009-07-01

This paper reports the results on alkylphenol and polycyclic aromatic hydrocarbons (PAH) pollution in mussels and cleans from Comunidad Valenciana coastal waters, in 2008. The significant presence of nonylphenol observed in both bivalves reflects an exposure to alkyl phenolic surfactants from the discharges of wastewater treatment plants that treat industrial and urban wastewaters, where the presence of alkylphenol polyethoxylated is common due to its extensive use (detergents, solubilizers...). The presence of low levels of PAH was observed in most of the studied areas. However, it must be highlighted that bivalves consumption does not imply any risk for human health. (Author) 21 refs.

Le modèle judiciaire libéral mis à l’épreuve : la surveillance des juges sous le Directoire

OpenAIRE

Berger, Emmanuel

2007-01-01

La justice du Directoire est principalement identifiée aux différentes violations infligées par le gouvernement afin de contrôler le pouvoir judiciaire et durcir la répression criminelle. Cette représentation est, en réalité, partiale. L’auteur tente de le prouver à travers l’analyse d’un aspect essentiel du système judiciaire directorial : la surveillance des juges. L’étude des normes et des pratiques montre que le mode de surveillance établi par le code des délits et des peines respecte la ...

Bioaccumulation of selected metals in bivalves (Unionidae) and Phragmites australis inhabiting a municipal water reservoir

OpenAIRE

Rzymski, Piotr; Niedzielski, Przemysław; Klimaszyk, Piotr; Poniedziałek, Barbara

2014-01-01

Urbanization can considerably affect water reservoirs by, inter alia, input, and accumulation of contaminants including metals. Located in the course of River Cybina, Maltański Reservoir (Western Poland) is an artificial shallow water body built for recreation and sport purposes which undergoes restoration treatment (drainage) every 4 years. In the present study, we demonstrate an accumulation of nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in water, sediment, three bivalve species (Anodo...

Rôle des universités dans le renforcement des technologies de l ...

International Development Research Centre (IDRC) Digital Library (Canada)

Rôle des universités dans le renforcement des technologies de l'information et de la communication au service du développement (TIC-D) en Asie. Jusqu'à maintenant, les efforts déployés dans le secteur de l'enseignement supérieur ont surtout été axés sur le téléapprentissage, l'apprentissage électronique et différentes ...

Le Mouvement Social

OpenAIRE

FRIDENSON, Patrick

2003-01-01

J'ai la faiblesse d'affirmer que parmi les revues françaises d'histoire Le Mouvement Social est la revue qui a publié le plus d'articles et de comptes rendus en matière d'histoire des femmes et du gender. Chacun peut le vérifier grâce à nos pages Web sur le site Internet du Dictionnaire créé par Jean Maitron. Elles comportent la table des matières complète de la revue depuis sa fondation en 1960. Notre rédaction est extrêmement fière de ce résultat. Mais elle reconnaît qu'il a été difficile à...

Source and impact of lead contamination on {delta}-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

Energy Technology Data Exchange (ETDEWEB)

Company, R.; Serafim, A.; Lopes, B.; Cravo, A. [CIMA, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Kalman, J.; Riba, I.; DelValls, T.A. [Catedra UNESCO/UNITWIN/WiCop, Department of Physical-Chemistry, Faculty Marine and Environmental Sciences, University of Cadiz, 11510 Puerto Real, Cadiz (Spain); Blasco, J. [Instituto Ciencias Marinas Andalucia (CSIC), Campus Rio San Pedro, 11510 Puerto Real, Cadiz (Spain); Delgado, J. [Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Sarmiento, A.M. [Catedra UNESCO/UNITWIN/WiCop, Department of Physical-Chemistry, Faculty Marine and Environmental Sciences, University of Cadiz, 11510 Puerto Real, Cadiz (Spain); Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Nieto, J.M. [Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Shepherd, T.J.; Nowell, G. [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Bebianno, M.J., E-mail: mbebian@ualg.pt [CIMA, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

2011-01-17

Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme ({delta}-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagon, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ({sup 206}Pb/{sup 204}Pb, {sup 207}Pb/{sup 204}Pb and {sup 208}Pb/{sup 204}Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50 {+-} 1.09 {mu}g g{sup -1} Pb d.w.) and D. trunculus (1.95 {+-} 0.10 {mu}g g{sup -1} Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels (<0.38 {mu}g g{sup -1} Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD = -0.36[Pb] + 0.79; r = 0.837; or exponential for M. galloprovincialis ALAD = 2.48e{sup -8.3[Pb]}; r = 0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in

Source and impact of lead contamination on δ-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

International Nuclear Information System (INIS)

Company, R.; Serafim, A.; Lopes, B.; Cravo, A.; Kalman, J.; Riba, I.; DelValls, T.A.; Blasco, J.; Delgado, J.; Sarmiento, A.M.; Nieto, J.M.; Shepherd, T.J.; Nowell, G.; Bebianno, M.J.

2011-01-01

Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme (δ-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagon, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ( 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50 ± 1.09 μg g -1 Pb d.w.) and D. trunculus (1.95 ± 0.10 μg g -1 Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels ( -1 Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD = -0.36[Pb] + 0.79; r = 0.837; or exponential for M. galloprovincialis ALAD = 2.48e -8.3[Pb] ; r = 0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in marine bivalve species with different feeding habits. Lead isotope data

Le faussaire roman

CERN Document Server

D'Anna, Gianfranco

2016-01-01

À l'aube du XXIe siècle, le monde de la science est sur le point de vivre une révolution. Le jeune physicien allemand Albert Hendrick Thebell, des célèbres laboratoires de recherche B-Labs, à Summit, dans le New Jersey, publie, dans les plus grandes revues scientifiques internationales, une série d'articles dans lesquels il prétend avoir obtenu des résultats extraordinaires qui pourraient révolutionner les bases mêmes de la technologie. Rapidement, la communauté scientifique puis les médias saluent en lui un futur prix Nobel; on compare même son génie à celui d'Albert Einstein. Le progrès scientifique semble avoir franchi une étape décisive, susceptible d'amener un futur meilleur. Mais ces découvertes sont-elles authentiques ? Car pendant ce temps, dans les mêmeslaboratoires, des voix s'élèvent pour contester non seulement les théories de Thebell mais aussi la légitimité même de ses expériences ; certains le soupçonnent d'avoir combiné la plus grande fraude scientifique de tous l...

Le rôle du pharmacien dans la fécondation in vitro

OpenAIRE

Hannoun , Odélia

2017-01-01

La procréation médicalement assistée regroupe plusieurs techniques venant en aide aux couples ayant des difficultés à concevoir. Environ 15% des couples en age de procréer consultent pour une difficulté à concevoir. Ce véritable problème de société nous incite à réfléchir sur le role que tient le pharmacien en tant que professionnel de santé dans le parcours de fécondation in vitro. Le pharmacien développe une relation étroite avec les patients au comptoir. Il est la pour expliquer le traitem...

A critical examination of the possible application of zinc stable isotope ratios in bivalve mollusks and suspended particulate matter to trace zinc pollution in a tropical estuary.

Science.gov (United States)

Araújo, Daniel; Machado, Wilson; Weiss, Dominik; Mulholland, Daniel S; Boaventura, Geraldo R; Viers, Jerome; Garnier, Jeremie; Dantas, Elton L; Babinski, Marly

2017-07-01

The application of zinc (Zn) isotopes in bivalve tissues to identify zinc sources in estuaries was critically assessed. We determined the zinc isotope composition of mollusks (Crassostrea brasiliana and Perna perna) and suspended particulate matter (SPM) in a tropical estuary (Sepetiba Bay, Brazil) historically impacted by metallurgical activities. The zinc isotope systematics of the SPM was in line with mixing of zinc derived from fluvial material and from metallurgical activities. In contrast, source mixing alone cannot account for the isotope ratios observed in the bivalves, which are significantly lighter in the contaminated metallurgical zone (δ 66 Zn JMC  = +0.49 ± 0.06‰, 2σ, n = 3) compared to sampling locations outside (δ 66 Zn JMC  = +0.83 ± 0.10‰, 2σ, n = 22). This observation suggests that additional factors such as speciation, bioavailability and bioaccumulation pathways (via solution or particulate matter) influence the zinc isotope composition of bivalves. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preliminary Results on the Evaluation of the Occurrence of Tetrodotoxin Associated to Marine Vibrio spp. in Bivalves from the Galician Rias (Northwest of Spain

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Jose Manuel Leão

2018-03-01

Full Text Available Tetrodotoxins (TTX are a potent group of natural neurotoxins putatively produced by symbiotic microorganisms and affecting the aquatic environment. These neurotoxins have been recently found in some species of bivalves and gastropods along the European Coasts (Greece, UK, and The Netherlands linked to the presence of high concentrations of Vibrio, in particular Vibrio parahaemolyticus. This study is focused on the evaluation of the presence of Vibrio species and TTX in bivalves (mussels, oysters, cockles, clams, scallops, and razor clams from Galician Rias (northwest of Spain. The detection and isolation of the major Vibrio spp. and other enterobacterial populations have been carried out with the aim of screening for the presence of the pathways genes, poliketide synthase (PKS and non-ribosomal peptide synthetase (NRPS possibly involved in the biosynthesis of these toxins. Samples containing Vibrio spp. were analyzed by biochemical (API20E-galery and genetic tests (PCR-RT. These samples were then screened for TTX toxicity by a neuroblastoma cell-based assay (N2a and the presence of TTX was further confirmed by LC-MS/MS. TTX was detected in two infaunal samples. This is the first confirmation of the presence of TTX in bivalve molluscs from the Galician Rias.

Le boson et le chapeau mexicain un nouveau grand récit de l'univers

CERN Document Server

Cohen-Tannoudji, Gilles

2013-01-01

Le boson ? C'est l'ultime particule élémentaire prédite par la théorie de l'infiniment petit, qui manquait encore et dont la découverte, grâce au grand collisionneur de hadrons du CERN, a été annoncée au monde entier le 4 juillet 2012. Postulée en 1964 par Robert Brout, François Englert et Peter Higgs, elle explique que le photon - particule qui transmet la force électromagnétique - n'a pas de masse, à l'encontre de celles véhiculant la force faible. Une telle dissymétrie était a priori incompatible avec la symétrie fondamentale, dite «de jauge», sur laquelle est fondé le modèle standard de la physique des particules. Le chapeau mexicain ? C'est le mécanisme grâce auquel le boson rend compte, en préservant les acquis du modèle standard, de l'origine des masses des particules élémentaires. Le boson et le chapeau mexicain se placent à la croisée - retracée par les deux auteurs en dialogue avec François Englert - des chemins de l'évolution des théories de l'astrophysique contemp...

Traces (ichnospecies Oichnus paraboloides of predatory gastropods on bivalve shells from the Seogwipo Formation, Jejudo, Korea

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Dal-Yong Kong

2015-12-01

Full Text Available Circular to subcircular drill holes were identified on the bivalve shells collected from the Seogwipo Formation, Jejudo, Korea. A great majority of the drill holes (>70% were found on the surfaces of a bivalve species Glycymeris rotunda. They are characterized by a beveled sharp edge and paraboloid in cross section with larger outer borehole diameter (OBD; mean 4.21 mm and smaller inner borehole diameter (mean 2.94 mm. Walls of the drill holes are generally smooth, and walls ornamented with etched relief-like structures were also recognized. A slightly raised central boss observed in an incomplete specimen may indicate a failure of predator’s attack. All drill holes collected are classified as a single ichnospecies Oichnus paraboloides Bromley, 1981. They are interpreted as boring traces produced by predatory gastropods, particularly naticid gastropods. Most O. paraboloides boreholes are observed in the central area of shell surfaces; a few boreholes lie marginally, which may reflect a borehole-site selectivity. No correlation between size of prey (shell height and size of predator (OBD is recognized. It is likely, however, that drilled shells of about 30 mm in height represent optimal prey size for naticid predators that lived in a benthic Seogwipo community.

Immunotoxicity of nanoparticle nTiO2 to a commercial marine bivalve species, Tegillarca granosa.

Science.gov (United States)

Shi, Wei; Han, Yu; Guo, Cheng; Zhao, Xinguo; Liu, Saixi; Su, Wenhao; Zha, Shanjie; Wang, Yichen; Liu, Guangxu

2017-07-01

The increasing production and extensive application of nanoparticles (NPs) inevitably leads to increased release of NPs into the marine environment and therefore poses a potential threat to marine organisms, especially the sessile benthic bivalves. However, the impacts of NPs on the immunity of commercial and ecological important bivalve species, Tegillarca granosa, still remain unknown to date. In addition, the molecular mechanism of the immunotoxicity of NPs still remains unclear in marine invertebrates. Therefore, the immunotoxicity of nTiO 2 exposure to T. granosa at environmental realistic concentrations was investigated in the present study. Results obtained showed that the total number, phagocytic activity, and red granulocytes ratio of the haemocytes were significantly reduced after 30 days nTiO 2 exposures at the concentrations of 10 and 100 μg/L. Furthermore, the expressions of genes encoding Pattern Recognition Receptors (PPRs) and downstream immune-related molecules were significantly down-regulated by nTiO 2 exposures, indicating a reduced sensitivity to pathogen challenges. In conclusion, evident immunotoxicity of nTiO 2 to T. granosa at environmental realistic concentrations was detected by the present study. In addition, the gene expression analysis suggests that the PRRs (both TLRs and RIG1 investigated) may be the molecules for NPs recognition in marine invertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

Entre les violences conjugales et le harcèlement moral : le stalking .

Directory of Open Access Journals (Sweden)

Nicolas Desurmont

2007-09-01

Full Text Available Ce livre de la criminologue Murielle Anteo est le premier publié en langue française sur le stalking si l’on excepte les travaux encore inédits de Virginie Léon (2004. Comme le rappelle l’auteure, le terme est emprunté à l’anglais to stalk (hanter, rôder, et désigne un comportement menaçant, initié par un individu dont l’objectif conscient ou inconscient est l’objectivation de sa victime à des fins de domination. L’agression prend différentes formes : ...

Le jeu de la création : Le mangeur (2005) de Ying Chen

OpenAIRE

Nicole Dunham

2013-01-01

Le théoricien James Hans définit le jeu comme une déconstruction structurante, un processus de perpétuelle remise en question. Dans Le Mangeur (2005) de Ying Chen, la narratrice revit un épisode d’une de ses vies passées où elle meurt mangée, avalée, par son père, descendant dans le « tunnel » du ventre de ce dernier. Cependant, suite à cet événement, elle se retrouve dans un autre espace-temps où elle rencontre son mari, A.. Une équivalence s’établit dans le roman entre les éléments suivants...

Abnormalities in bivalve larvae from the Puck Bay (Gulf of Gdansk, southern Baltic Sea) as an indicator of environmental pollution.

Science.gov (United States)

Lasota, Rafal; Gierszewska, Katarzyna; Viard, Frédérique; Wolowicz, Maciej; Dobrzyn, Katarzyna; Comtet, Thierry

2018-01-01

This study described the occurrence of abnormalities in bivalve larvae from the Puck Bay. Analyses of plankton samples collected in 2012-2013 showed that larval Mytilus trossulus, Mya arenaria, and Cerastoderma glaucum exhibited abnormalities that could indicate adverse environmental impacts. The deformities were mainly in shells, but missing soft tissue fragments and protruding vela were also noted. In addition to larval studies, we analyzed benthic postlarvae of Mytilus trossulus. Interestingly, grooves and notches at different locations of the prodissoconch, dissoconch, and shell margin were observed. Some of these deformations were reminiscent of the indentations found on the shell edge of larvae. Comparing the proportion of abnormal postlarvae to larvae with shell abnormalities suggested that the survival of larvae with shell abnormalities was low. Overall, our results suggested that the ratio of abnormal bivalve larvae could be used as an indicator of the biological effects of hazardous substances in the pelagic environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Transgenerational exposure of North Atlantic bivalves to ocean acidification renders offspring more vulnerable to low pH and additional stressors.

Science.gov (United States)

Griffith, Andrew W; Gobler, Christopher J

2017-09-12

While early life-stage marine bivalves are vulnerable to ocean acidification, effects over successive generations are poorly characterized. The objective of this work was to assess the transgenerational effects of ocean acidification on two species of North Atlantic bivalve shellfish, Mercenaria mercenaria and Argopecten irradians. Adults of both species were subjected to high and low pCO 2 conditions during gametogenesis. Resultant larvae were exposed to low and ambient pH conditions in addition to multiple, additional stressors including thermal stress, food-limitation, and exposure to a harmful alga. There were no indications of transgenerational acclimation to ocean acidification during experiments. Offspring of elevated pCO 2 -treatment adults were significantly more vulnerable to acidification as well as the additional stressors. Our results suggest that clams and scallops are unlikely to acclimate to ocean acidification over short time scales and that as coastal oceans continue to acidify, negative effects on these populations may become compounded and more severe.

Le CRDI en Colombie

International Development Research Centre (IDRC) Digital Library (Canada)

Le CRDI appuie la recherche en Colombie dans des domaines tels ... Le CRDI a soutenu des activités de longue haleine qui ont eu pour ... Des travaux subventionnés par le CRDI ont aidé une fondation à intégrer Internet à son programme ...

La construction de la matière le modèle Standard

CERN Document Server

Léon, Jacques

2016-01-01

Qu'est-ce que la matière ? Voilà une question à laquelle il pourrait sembler facile de répondre car il n'est rien de plus concret que la matière. Et pourtant, la réponse qu'en donne la physique contemporaine est pour le moins déconcertante ! Le concept-même de particules, briques élémentaires de la matière, s'est volatilisé, dissout dans des objets mathématiques abstraits et abscons pour les non-initiés. Plus nos théories sont précises et plus l'image qu'elles nous renvoient est insaisissable. En un siècle, la représentation des particules s'est métamorphosée en nuages de probabilité portés par des champs quantiques régis par des symétries confinées dans des espaces abstraits. Mais dans un même temps, nous avons réussi le tour de force d'expliquer toute cette complexité avec seulement 16 particules… et une seule théorie, véritable construction de notre conception de la matière : le modèle standard. Ce livre tente de guider le lecteur dans le dédale de la physique des particu...

Intelligence artificielle et agents collectifs : le modèle EUROSIM

Directory of Open Access Journals (Sweden)

Denise Pumain

2007-07-01

Full Text Available EUROSIM est un modèle multi-agents conçu pour simuler l’évolution à moyen terme du système des villes européennes. Les agents sont des entités collectives, les grandes villes caractérisées par leur taille et leur fonction dans le système des villes, et dont les interactions (échanges modulés par des relations de proximité ou de réseau déterminent la dynamique relative, tandis que la croissance d’ensemble dépend de l’innovation. Des outils d’analyse multiscalaire ont été développés afin d’interpréter les sorties du modèle et faciliter le calibrage.

ÉTUDE DE CAS — Cuba : Le logement et le capital humain à Cuba ...

International Development Research Centre (IDRC) Digital Library (Canada)

10 janv. 2011 ... ÉTUDE DE CAS — Cuba : Le logement et le capital humain à Cuba ... Centre de recherches pour le développement international (CRDI) du Canada révèle ... Les ressources déjà limitées sont devenues encore plus rares. ... de l'Institut national pour l'hygiène, l'épidémiologie et la microbiologie (INHEM), ...

Le Rôle du langage de programmation dans la réalisation de code ...

African Journals Online (AJOL)

Le Rôle du langage de programmation dans la réalisation de code de qualité, les cas de Delphi et C++ Nous discutons dans ce papier le rôle du langage de programmation dans la production d'un code de qualité. La qualité d'un code peut être atteinte en respectant certains critères simples au niveau de la programmation ...

Gossip Girls : le rôle du potin dans quelques romans pour adolescentes

Directory of Open Access Journals (Sweden)

Daniela Di Cecco

2014-04-01

Full Text Available Cet article explore le rôle joué par le potin dans une sélection de romans anglophones publiés aux Etats-Unis et au Canada pour adolescentes et préadolescentes. Des études psychologiques et sociologiques récentes sur les agressions féminines et la façon dont les filles infligent de la peine aux autres filles de façon indirecte et voilée servent de cadre à notre analyse. Le fait que la violence physique soit considérée comme un comportement réservé aux garçons et donc inapproprié pour les filles, incite les adolescentes à agir autrement. Le potin devient parfois une arme pour marginaliser ou punir une fille, mais il peut aussi jouer un rôle positif au niveau de la cohésion d’une bande et de la solidarité entre filles.

Impact of seawater carbonate chemistry on the calcification of marine bivalves

Science.gov (United States)

Thomsen, J.; Haynert, K.; Wegner, K. M.; Melzner, F.

2015-07-01

Bivalve calcification, particularly of the early larval stages, is highly sensitive to the change in ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32-] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the exact carbonate system component by which growth and calcification are affected it is necessary to utilize more complex carbonate chemistry manipulations. As single factors, pCO2 had no effects and [HCO3-] and pH had only limited effects on shell growth, while lowered [CO32-] strongly impacted calcification. Dissolved inorganic carbon (CT) limiting conditions led to strong reductions in calcification, despite high [CO32-], indicating that [HCO3-] rather than [CO32-] is the inorganic carbon source utilized for calcification by mytilid mussels. However, as the ratio [HCO3-] / [H+] is linearly correlated with [CO32-] it is not possible to differentiate between these under natural seawater conditions. An equivalent of about 80 μmol kg-1 [CO32-] is required to saturate inorganic carbon supply for calcification in bivalves. Below this threshold biomineralization rates rapidly decline. A comparison of literature data available for larvae and juvenile mussels and oysters originating from habitats differing substantially with respect to prevailing carbonate chemistry conditions revealed similar response curves. This suggests that the mechanisms which determine sensitivity of calcification in this group are highly conserved. The higher sensitivity of larval calcification seems to primarily result from the much higher relative calcification rates in early life stages. In order to reveal and understand the mechanisms that limit or facilitate adaptation to future ocean acidification, it is necessary to better

205 Le Role de la Litterature dans le Developpement de la Nation ...

African Journals Online (AJOL)

Ike Odimegwu

du plaisir en même temps qu'il le moralise. Elle fait naître dans ses lecteurs ou dans son audience des .... développement de l'esprit>>(319)Par cette définition nous comprenons que le développement signale qu'il du progrès ... qu'elle est une œuvre de l'imagination qui aide l'homme à transcender le monde physique.

Rapport financier trimestriel pour le trimestre qui a pris fin le 30 juin ...

International Development Research Centre (IDRC) Digital Library (Canada)

Sophie Comeau

30 juin 2017 ... Régi par la Loi sur le Centre de recherches pour le développement international ... des retombées; forme des leaders dans les secteurs de l'administration .... Au cours de la période de trois mois qui a pris fin le 30 juin 2017, ...

Bivalves: From individual to population modelling

Science.gov (United States)

Saraiva, S.; van der Meer, J.; Kooijman, S. A. L. M.; Ruardij, P.

2014-11-01

An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg mortality, background mortality, food competition, and predation (including cannibalism) were additional population processes. Model properties were studied through the analysis of theoretical scenarios and by simulation of different mortality parameter combinations in a realistic setup, imposing environmental measurements. Realistic criteria were applied to narrow down the possible combination of parameter values. Field observations obtained in the long-term and multi-station monitoring program were compared with the model scenarios. The realistically selected modeling scenarios were able to reproduce reasonably the timing of some peaks in the individual abundances in the mussel bed and its size distribution but the number of individuals was not well predicted. The results suggest that the mortality in the early life stages (egg and larvae) plays an important role in population dynamics, either by initial egg mortality, larvae dispersion, settlement failure or shrimp predation. Future steps include the coupling of the population model with a hydrodynamic and biogeochemical model to improve the simulation of egg/larvae dispersion, settlement probability, food transport and also to simulate the feedback of the organisms' activity on the water column properties, which will result in an improvement of the food quantity and quality characterization.

Le jeu de la création : Le mangeur (2005 de Ying Chen

Directory of Open Access Journals (Sweden)

Nicole Dunham

2013-11-01

Full Text Available Le théoricien James Hans définit le jeu comme une déconstruction structurante, un processus de perpétuelle remise en question. Dans Le Mangeur (2005 de Ying Chen, la narratrice revit un épisode d’une de ses vies passées où elle meurt mangée, avalée, par son père, descendant dans le « tunnel » du ventre de ce dernier. Cependant, suite à cet événement, elle se retrouve dans un autre espace-temps où elle rencontre son mari, A.. Une équivalence s’établit dans le roman entre les éléments suivants : le ventre du père, les tableaux peints par ce dernier et l’espace-temps de A., et la fenêtre. Ces éléments deviennent des aires de jeu, remettant en question les concepts de l’intérieur et de l’extérieur et du créateur et de l’œuvre. En nous servant du texte « Le Tunnel » écrit par Ying Chen, nous démontrerons que cette notion du jeu s’applique également à l’ensemble de son œuvre.

Le facteur humain et la sûreté de fonctionnement dans le ...

African Journals Online (AJOL)

Elle permettait d'optimiser le couple « performance-coût », en identifiant, évaluant et maîtrisant les pannes qu'il ... gestion des risques deviennent une ...... Etre en mesure de détecter les .... variés qui s'y déroulent, avoir le contrôle du.

Polychlorinated biphenyls, organochlorine pesticides and polycyclic aromatic hydrocarbons in a one-off global survey of bivalves

DEFF Research Database (Denmark)

Vorkamp, Katrin; Strand, Jakob; Christensen, Jan H.

2010-01-01

During the Danish Galathea 3 expedition, bivalve samples were collected at the Faroe Islands, Greenland, Ghana, South Africa, Australia, Solomon Islands, New Zealand, Chile, US Virgin Islands, Boston, Newfoundland and Shetland Islands and analysed for organochlorines and PAHs. Concentration...... in terms of PCB and PAH levels, while other Greenland samples came closest to representing PAH background levels. Several locations had undetectable organochlorine levels, including Hobart and Chile, which had the lowest Sigma PAH concentrations (group the stations...

Le rôle de l’audit interne dans le pilotage et la performance du système de contrôle interne : cas d’un échantillon d’entreprises algériennes

OpenAIRE

Chekroun, Meriem

2013-01-01

Les scandales financiers qui ont ébranlé récemment les entreprises publiques algériennes, telle que l’entreprise Sonatrach, ont mis sur le devant de la scène la nécessité de renforcer le système de contrôle interne (SCI) qui est considéré de plus en plus comme une solution à un large éventail de problèmes latents ( les problèmes d’ordre éthique,…), y compris la fonction d’audit interne ayant un rôle prépondérant dans le pilotage et la performance du SCI. Pour ce faire, l’audit ...

Uptake and loss of 134Cs and 60Co by the Baltic bivalve Macoma Baltica under laboratory conditions

International Nuclear Information System (INIS)

Evans, S.

1982-01-01

In order to predict the radiological impact on man via harvestable sea food products, it is essential to make a critical evaluation of the transfer routes and the rates on which radionuclides are transferred through the aquatic food chains. In the Baltic, the bivalve Macoma Baltica comprises a main food item for fish species of commercial interest, such as flounder. The accumulation and release of Cs-134 and Co-60 by Macoma was experimentally investigated. The nuclides were added to the water and the activity content of the bivalves was determined at regular intervals. The uptake was quite rapid, 40 per cent (Cs) and 55 per cent (Co) respectively of the final steady state was obtained after 24 hours. The subsequent release was rapid as well, 50 per cent (Cs) and 40 per cent (Co) respectively of the accumulated activity was lost within 6 days. The experiments demonstrated that the major intake route following short-term releases of activity will be from the water column. The close connection between activity in water and organism can thus be used for predictive purposes without the complication of radionuclide uptake from contaminated sediments. (Author)

Le rôle des institutions dans le processus de l’innovation ; l’apport de Thorstein Veblen

Directory of Open Access Journals (Sweden)

Diane-Gabrielle Tremblay

2007-10-01

Full Text Available Nous nous intéressons ici au rôle des institutions dans le processus de l’innovation, puisque Veblen le met en valeur. Cet apport de Veblen nous paraît déterminant pour mieux comprendre l’innovation, surtout que l’on parle de plus en plus d’une diversité de formes d’innovation (technologique, mais aussi organisationnelle, sociale et de produit, et que celles-ci sont mieux comprises lorsque l’on tient compte du rôle des institutions dans la diffusion ou le blocage de l’innovation. Veblen met aussi en évidence le caractère parfois retardataire des institutions, ainsi que la réciprocité des effets entre technologie et institutions, autant d’éléments fort pertinents pour l’analyse, encore aujourd’hui.This paper addresses the role of institutions in the process of innovation, since Veblen highlights this role. This contribution of Veblen appears determinant to better understand the process of innovation, especially in a context where we are more and more interested in various forms of innovation (technological, but also organisational, social and product innovations; these various forms of innovation are better understood and analysed when the role of institutions in their diffusion or lack of diffusion is taken into account. Veblen also highlights the fact that institutions sometimes block or slow down the process of diffusion of innovations, as well as the reciprocity of effects between technology and institutions, contributions which are all the more important for the analysis of innovation today.

Bâle 3 : Quels impacts sur le financement des pays émergents ?

OpenAIRE

Figuet, Jean-Marc; Humblot, Thomas; Lahet, Delphine

2013-01-01

La persistance de crises bancaires démontre l'incapacité des établissements de crédit à s'autoréguler. De ce fait, le Comité de Bâle étend largement le périmètre de la nouvelle règlementation prudentielle. Sur la base de la littérature sur les déterminants des flux de capitaux transfrontières et d'un GMM système, cet article analyse l'impact potentiel de l'accord Bâle 3 sur les flux de capitaux bancaires provenant des banques de 16 pays industrialisés à destination d'un panel de 30 pays émerg...

Le glaive et la chair : le pouvoir et son incarnation au temps des derniers Valois

OpenAIRE

Roux, Nicolas Le

2014-01-01

Au xvie siècle, pouvait-on concevoir la monarchie autrement qu’incarnée ? Servir le roi, c’était servir un prince auquel on était lié personnellement, et non une institution abstraite. Le monarque devait apparaître comme un compagnon pour la noblesse militaire. Henri II représentait le modèle du roi chevalier. Contrairement à son père, Charles IX ne faisait pas la guerre, mais il épuisait son corps dans d’interminables chasses. Henri III a tenu dans sa jeunesse le rôle de chef de guerre. Deve...

Le don gratuit. Le cas d'un établissement public

OpenAIRE

Barel , Yvan; Frémeaux , Sandrine

2008-01-01

Disponible en ligne : http://www.annales.org/gc/2008/gc94/barel.pdf; La logique de la réciprocité est le cadre d'analyse dominant de la relation de travail. La logique du don/contredon s'inscrit dans ce même cadre de référence, en postulant qu'aucune relation d'échange ne peut survivre à une situation d'asymétrie trop forte (MAUSS, 1924). Mais elle ajoute une idée nouvelle en mettant en exergue le " tabou du calcul " (BOURDIEU, 1980) : le désir de contredon n'est pas toujours manifesté, ni mê...

Le salaire minimum n'est pas toujours le meilleur moyen d'accroître ...

International Development Research Centre (IDRC) Digital Library (Canada)

4 mai 2016 ... De fait, cette intervention vigoureuse sur le marché du travail est une ... la mobilité des travailleurs entre le secteur structuré et le secteur non structuré, ... On peut certes se constituer rapidement du capital politique en faisant ...

Bibliographie sélective sur le corps

Directory of Open Access Journals (Sweden)

Anne-Claire Rebreyend

2007-11-01

Full Text Available Ouvrages générauxBruit Zaidman Louise, Houbre Gabrielle, Klapisch-Zuber Christiane, Schmitt Pantel Pauline (dir., Le corps des jeunes filles de l'Antiquité à nos jours, Paris, Perrin, 2001.Vigarello Georges, Le propre et le sale. L'hygiène du corps depuis le Moyen Âge, Paris, Seuil, 1985.—, Le sain et le malsain : santé et mieux-être depuis le Moyen Âge, Paris, Seuil, 1993.—, Histoire de la beauté. Le corps et l'art d'embellir de la Renaissance à nos jours, Paris, Seuil, 2004.Le corps au Moy...

Late Devonian (Frasnian) bivalves from the Nocedo Formation: the results of Wilhelm Kegel’s 1927 field trip to northern Spain

NARCIS (Netherlands)

Amler, M.R.W.

2010-01-01

During a field trip to the Peña-Corada Unit of the southernmost Esla region of the Cantabrian Mountains in 1927, the German stratigrapher Wilhelm Kegel sampled brachiopods and bivalves from a section in the Laoz valley near La Ercina. The stratigraphic position is believed to be part of the Nocedo

Rapport financier trimestriel pour le trimestre qui a pris fin le 30 juin

International Development Research Centre (IDRC) Digital Library (Canada)

Office 2004 Test Drive User

30 juin 2016 ... Le CRDI finance des travaux de recherche appliquée ... développement international (le Centre) et lʼévolution de la ..... voie de développement et sur la mise en oeuvre des connaissances scientifiques, techniques et autres en vue .... Les accords expirent à des dates différentes, et le dernier prend fin en.

Physiological effects of hypercapnia in the deep-sea bivalve Acesta excavata (Fabricius, 1779) (Bivalvia; Limidae)

DEFF Research Database (Denmark)

Hammer, Karen M.; Kristiansen, Erlend; Zachariassen, Karl Erik

2011-01-01

The option of storing CO(2) in subsea rock formations to mitigate future increases in atmospheric CO(2) may induce problems for animals in the deep sea. In the present study the deep-sea bivalve Acesta excavata was subjected to environmental hypercapnia (pHSW 6.35, P(CO2), =33,000 mu atm...... extracellular pH remained significantly lower during recovery. Intracellular non-bicarbonate buffering capacity of the posterior adductor muscle of hypercapnic animals was significantly lower than control values, but this was not the case for the remaining tissues analyzed. Oxygen consumption initially dropped...

Tumelo le Moruo

Directory of Open Access Journals (Sweden)

Vuyani S. Vellem

2015-03-01

Full Text Available Paleng ya rona batho ba batsho, tumelo ya boKreste e fihlile lefatsheng la rona la Afrika Borwa mmoho le dikgoka tsa ditjhaba tsa boPhirima. BoKreste bo fihlile ka nako ya dintwa tseo mohopolo wa tsona e neng e le ho hapa lefatshe la, batho ba batsho. Ka mantswe amang, rona batho ba batsho, re ile ra qetella re le setjhaba se ileng sa hlolwa, mme lefatshe la rona la nkuwa ka dikgoka. Ka hare ho dikgoka tsena, ho ne ho dutse tumelo ya boKreste. Makgowa a ile are: �A re kwaleng mahlo re rapeleng, rona ra kwala mahlo, mme ha re qeta hore Amen, re bula mahlo, ra fumana lefatshe le nkuwe matsohong a rona ho setse Bibele.� Re ile ra sala le Bibele eo ka yona re lekileng dilemong tse fitileng ho lwana ntwa ya topollo, kapa tokoloho hofihlela selemong sa 1994. Le ha re ile ra fumana tokoloho ka selemo seo, hare so ka re lokoloha ho tsa moruo. E kaba sena se bolela eng mabapi le tumelo ya rona ya boKreste? Segolweng sena re leka ho araba potso ena. Tumelo ke eng ho batho ba sa lokolohang moruong wa naha ya bona? Re lekola pale ya boKreste, tumelo ya batho le maemo a kereke ntlheng ya ho tadimana le tokoloho ka tumelo.Faith and economics. In our history from a black perspective, Christianity arrived through violent conquest from the west. Evidentially, this faith coincided with wars of dispossession and the ultimate defeat of black Africans. It is difficult to separate the violent defeat of black Africans from the arrival of Christian faith. This well-known statement within the circles of black Theology of liberation: When the white man arrived in our land he said, �let us pray and after prayer, when we opened our eyes, our land was taken and only the Bible was left in our hands,� captures the black sentiment of this history. Ironically, it was this Bible that black Africans used to wage their struggle for liberation up to the demise of apartheid in 1994.Nonetheless, political liberation is not enough as the struggle for economic liberation

Interactive effects of pH and metals on mitochondrial functions of intertidal bivalves Crassostrea virginica and Mercenaria mercenaria

International Nuclear Information System (INIS)

Ivanina, Anna V.; Sokolova, Inna M.

2013-01-01

Highlights: •Interactive effects of trace metals Cd and Cu and pH were studied in mitochondria of clams and oysters. •Mitochondrial respiration and membrane potential of bivalves were robust to pH variation (6.6–7.8). •Elevated levels of Cd and Cu inhibited mitochondrial respiration in the pH-dependent manner but did not affect the membrane potential. •Negative effects of Cd and Cd on mitochondrial respiration were alleviated at low pH (7.0 and below). •Moderate acidosis may protect molluscan mitochondria from metal toxicity. -- Abstract: Intertidal bivalves experience broad fluctuations of environmental temperature, pH and oxygen content which could change their intracellular pH. They are also exposed to trace metals such as cadmium (Cd) and copper (Cu) that accumulate in their tissues and may negatively affect mitochondrial functions and bioenergetics. We determined the interactive effects of pH and trace metals (25 μM Cd or Cu) on mitochondrial functions (including respiration and membrane potentials in both ADP-stimulated (state 3) and resting (state 4) states) of two common marine bivalves, the hard clams (Mercenaria mercenaria) and eastern oysters (Crassostrea virginica). In the absence of the trace metals, mitochondrial functions of C. virginica and M. mercenaria were insensitive to pH in a broad physiologically relevant range (6.6–7.8). Mitochondrial respiration was generally suppressed by 25 μM Cd or Cu (with the stronger effects observed for ADP-stimulated compared to the resting respiration) while the mitochondrial membrane potential was unaffected. pH modulated the effects of Cu and Cd on mitochondrial respiration of the bivalves. In oysters, Cu suppressed ADP-stimulated mitochondrial respiration at high and low pH values (6.6 and 7.8, respectively), but had no effect in the intermediate pH range (7.0–7.4). In clams, the negative effect of Cu on ADP-stimulated respiration was only observed at extremely high pH (7.8). A decrease in p

Interactive effects of pH and metals on mitochondrial functions of intertidal bivalves Crassostrea virginica and Mercenaria mercenaria

Energy Technology Data Exchange (ETDEWEB)

Ivanina, Anna V.; Sokolova, Inna M., E-mail: isokolov@uncc.edu

2013-11-15

Highlights: •Interactive effects of trace metals Cd and Cu and pH were studied in mitochondria of clams and oysters. •Mitochondrial respiration and membrane potential of bivalves were robust to pH variation (6.6–7.8). •Elevated levels of Cd and Cu inhibited mitochondrial respiration in the pH-dependent manner but did not affect the membrane potential. •Negative effects of Cd and Cd on mitochondrial respiration were alleviated at low pH (7.0 and below). •Moderate acidosis may protect molluscan mitochondria from metal toxicity. -- Abstract: Intertidal bivalves experience broad fluctuations of environmental temperature, pH and oxygen content which could change their intracellular pH. They are also exposed to trace metals such as cadmium (Cd) and copper (Cu) that accumulate in their tissues and may negatively affect mitochondrial functions and bioenergetics. We determined the interactive effects of pH and trace metals (25 μM Cd or Cu) on mitochondrial functions (including respiration and membrane potentials in both ADP-stimulated (state 3) and resting (state 4) states) of two common marine bivalves, the hard clams (Mercenaria mercenaria) and eastern oysters (Crassostrea virginica). In the absence of the trace metals, mitochondrial functions of C. virginica and M. mercenaria were insensitive to pH in a broad physiologically relevant range (6.6–7.8). Mitochondrial respiration was generally suppressed by 25 μM Cd or Cu (with the stronger effects observed for ADP-stimulated compared to the resting respiration) while the mitochondrial membrane potential was unaffected. pH modulated the effects of Cu and Cd on mitochondrial respiration of the bivalves. In oysters, Cu suppressed ADP-stimulated mitochondrial respiration at high and low pH values (6.6 and 7.8, respectively), but had no effect in the intermediate pH range (7.0–7.4). In clams, the negative effect of Cu on ADP-stimulated respiration was only observed at extremely high pH (7.8). A decrease in p

Quantitative analysis of nickel in zirconium and zircaloy; Dosage du nickel dans le zirconium et dans le zircaloy

Energy Technology Data Exchange (ETDEWEB)

Rastoix, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1957-07-01

A rapid spectrophotometric has been developed for determination of 10 to 1000 ppm of Ni in zirconium and zircaloy using dimethylglyoxime. Iron, copper, tin and chromium, do not interfere at the concentration usually present in zirconium and its alloys. (author) [French] On determine colorimetriquenent 10 a 1000 ppm de Ni dans le zirconium et le zircaloy par photo colorimetrie a 440 m{mu} de la dimethylglyoxime nickelique. Le dosage est rapide. Le fer, le cuivre, l'etain, le chrome ne genent pas aux concentrations habituellement rencontrees dans le zirconium et ses alliages. (auteur)

Le Bon, Gustave

DEFF Research Database (Denmark)

Borch, Christian

2017-01-01

Gustave Le Bon (1841–1931) was a French physician and crowd psychologist who published extensively on themes such as crowds, war, race, revolution, socialism, and war. His work on crowd psychology in particular was highly influential, including beyond scholarly circles. Le Bon argued that crowds...

Le Conseil des gouverneurs | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

2 nov. 2010 ... La gouvernance du CRDI. Reddition de comptes, transparence et efficacité. Au cours de l'exercice 2009–2010, le Conseil des gouverneurs du CRDI a adopté un nouveau cadre stratégique quinquennal, Le développement par l'innovation. Pendant de nombreux mois, les gouverneurs et les membres de la ...

Le Service Accueil et Contrôle d'Accès

CERN Document Server

Ducastel, C

1999-01-01

L'utilisateur qui vient au CERN pour la première fois, est accueilli généralement par les membres du service 'Accueil et Contrôle d'Accès'. Cet utilisateur sera tout d'abord orienté vers un des postes d'hôtesses d'accueil en charge de l'enregistrement et de la délivrance de cartes CERN. Les informations seront saisies et immédiatement disponibles et transmises, via le système AMS, aux équipements de contrôle d'accès et à la Centrale de Surveillance des accès, chargée de la supervision de tout le dispositif de contrôle d'accès au domaine. Ces contrôles aux entrées et accueil des visiteurs individuels sont complétés par des missions de surveillance à l'intérieur du Domaine pour les agents, et par des travaux de gestions de dossiers administratifs (service enregistrement) pour les hôtesses. Un contrat commun assure une uniformité de formation des agents et hôtesses. Ce contrat est assorti d'une clause de Bonus Malus afin de tendre vers une optimisation des performances.

Le paradigme du Mur dans le monde contemporain : évolution et perspectives 1989-2009

Directory of Open Access Journals (Sweden)

Hélène Yèche

2010-06-01

Full Text Available Il y a près de vingt ans, dans la nuit du 9 au 10 novembre 1989, disparaissait le mur de Berlin, symbole de la séparation de l’Europe en deux blocs antagonistes – d’un côté le camp soviétique, de l’autre le camp occidental. Le véritable tournant de ce que l’on a ensuite appelé la « révolution pacifique » eut cependant lieu un mois auparavant, le 9 octobre 1989, avec la première manifestation de masse qui réunit environ 70 000 personnes à Leipzig, RDA (ville plus tard honorée du titre de Helde...

Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

Energy Technology Data Exchange (ETDEWEB)

Foulquier, L; Bovard, P; Grauby, A [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1966-07-01

comparee a celles deja effectuees par d'autres auteurs permet de degager des idees generales sur le mode et la capacite de fixation du {sup 137}Cs par les lamellibranches. (auteur)

Le corps dans l’espace architectural. Le Corbusier, Claude Parent et Henri Gaudin

Directory of Open Access Journals (Sweden)

Julie Cattant

2016-12-01

Full Text Available Le premier geste de l’espace architectural est d’accueillir nos corps humains. En leur offrant un espacement à habiter, il leur permet de s’abriter, de se mouvoir et de se rencontrer. L’homme et l’architecture s’affectent l’un l’autre. Nombreux sont les architectes qui interrogent cette coexistence car, renouveler la pensée de l’espace nécessite de reconsidérer le corps humain. L’étude des relations entre le corps et l’espace chez trois architectes français sera l’occasion d’évoquer les écarts et les convergences entre l’homme et l’architecture. L’œuvre de Le Corbusier, protagoniste du mouvement moderne, maintient ainsi une distance entre un corps machinisé et un espace idéal. Marquée par un mode de pensée dualiste, l’architecture de Le Corbusier annonce toutefois son propre dépassement, dépassement que Claude Parent et Henri Gaudin opèreront par la suite à leur manière, le premier en introduisant l’oblique et la déstabilisation du corps, le second en transgressant la limite de l’espace et du corps pour envisager leur porosité réciproque. Finalement, c’est la manière dont l’homme appréhende l’espace avec son corps qui est questionnée par ces trois architectes, de la prégnance du visuel à son évincement.

Beware of ligand efficiency (LE): understanding LE data in modeling structure-activity and structure-economy relationships.

Science.gov (United States)

Polanski, Jaroslaw; Tkocz, Aleksandra; Kucia, Urszula

2017-09-11

On the one hand, ligand efficiency (LE) and the binding efficiency index (BEI), which are binding properties (B) averaged versus the heavy atom count (HAC: LE) or molecular weight (MW: BEI), have recently been declared a novel universal tool for drug design. On the other hand, questions have been raised about the mathematical validity of the LE approach. In fact, neither the critics nor the advocates are precise enough to provide a generally understandable and accepted chemistry of the LE metrics. In particular, this refers to the puzzle of the LE trends for small and large molecules. In this paper, we explain the chemistry and mathematics of the LE type of data. Because LE is a weight metrics related to binding per gram, its hyperbolic decrease with an increasing number of heavy atoms can be easily understood by its 1/MW dependency. Accordingly, we analyzed how this influences the LE trends for ligand-target binding, economic big data or molecular descriptor data. In particular, we compared the trends for the thermodynamic ∆G data of a series of ligands that interact with 14 different target classes, which were extracted from the BindingDB database with the market prices of a commercial compound library of ca. 2.5 mln synthetic building blocks. An interpretation of LE and BEI that clearly explains the observed trends for these parameters are presented here for the first time. Accordingly, we show that the main misunderstanding of the chemical meaning of the BEI and LE parameters is their interpretation as molecular descriptors that are connected with a single molecule, while binding is a statistical effect in which a population of ligands limits the formation of ligand-receptor complexes. Therefore, LE (BEI) should not be interpreted as a molecular (physicochemical) descriptor that is connected with a single molecule but as a property (binding per gram). Accordingly, the puzzle of the surprising behavior of LE is explained by the 1/MW dependency. This effect

Assessing the presence of marine toxins in bivalve molluscs from southwest India.

Science.gov (United States)

Turner, Andrew D; Dhanji-Rapkova, Monika; Rowland-Pilgrim, Stephanie; Turner, Lucy M; Rai, Ashwin; Venugopal, Moleyur N; Karunasagar, Indrani; Godhe, Anna

2017-12-15

The south west coast of India has been showing a steady increase in shellfish cultivation both for local consumption and fishery export, over recent years. Perna viridis and Crassostrea madrasensis are two species of bivalve molluscs which grow in some selected regions of southern Karnataka, close to the city of Mangalore. In the early 1980s, shellfish consumers in the region were affected by intoxication from Paralytic Shellfish Poison present in local bivalves (clams and oysters) resulting in hospitalisation of many, including one fatality. Since then, there have been no further reports of serious shellfish intoxication and there is little awareness of the risks from natural toxins and no routine monitoring programme in place to protect shellfish consumers. This study presents the findings from the first ever systematic assessment of the presence of marine toxins in mussels and oysters grown in four different shellfish harvesting areas in the region. Shellfish were collected and subjected to analysis for ASP, PSP and lipophilic toxins, as well as a suite of non-EU regulated toxins such as tetrodotoxin and selected cyclic imines. Results revealed the presence of low levels of PSP toxins in oysters throughout the study period. Overall, total toxicities reached a maximum of 10% of the EU regulatory limit of 800 μg STX eq/kg. Toxin profiles were similar to those reported from the 1980 outbreak. No evidence was found for significant levels of ASP and lipophilic toxins, although some cyclic imines were detected, including gymnodimine. The results indicated that the risk to shellfish consumers during this specific study period would have been low. However, with historical evidence for extremely high levels of PSP toxins in molluscs, there is a strong need for routine surveillance of shellfish production areas for marine toxins, in order to mitigate against human health impacts resulting from unexpected harmful algal blooms, with potentially devastating socio

Study on the bioaccumulation of Polonium-210 on bivalve indicator organisms of Tamilnadu and Pondicherry coast (East Coast of India)

International Nuclear Information System (INIS)

Syed Mohamed, H.E.; Sadiq Bukhari, A.; Meeramaideen, M.; Masilamani, V.; Shamsudin, Mohamed; Shahul Hameed, P.

2012-01-01

210 Po is a major contributor (90%) of the natural radiation dose from alpha-emitting radionuclides, received by most marine organisms. Among marine organisms, benthic fauna are superior to many other biological groups, since they could be monitored due to their sedentary habits and then must either adapt to environmental stress or perish. They also reflect the water conditions not only at the time of sampling but also for some past time as well. The affinity of 210 Po for protein enables it to pass through the food chain, and increased body burdens of 210 Po have been found where diets include protein-rich meat and seafood. The present study was launched to evaluate the rate of accumulation of 210 Po in the benthic bivalve molluscs such as Perna indica, P.viridis, Meretrix casta, Cardium coronatum, Gafrarium tumidum, Paphia textrix, Vellorita cyprinodea and Pinctada sp., of Tamilnadu and Pondicherry coast. Water samples, sediments and bivalves were collected from Gulf of Mannar (6 sampling stations), Palk Strait (8 sampling stations) of Tamilnadu and Pondicherry (6 sampling stations). 210 Po determination as made was as per standard protocols. The results showed that 210 Po concentration in coastal waters of Gulf of Mannar, Palk Strait and Pondicherry ranged 0.5 - 2.83 mBq/l (mean 1.33 mBq/I), 2.14 - 32.14 mBq/l (mean 15.3 mBq/l) and 1.36 - 2.0 mBq/1 (mean 1.59 mBq/1) respectively. The sediments maintained higher level of 210 Po (mean value of 3.62 Bq/kg in Gulf of Mannar, 107.9 Bq/kg in Palk Strait and 3.0 Bq/kg in Pondicherry) than water. The 210 Po rich sediment therefore serves as a vital link in the transfer of Polonium from water to the marine organisms. The concentration of 210 Po in eight species of bivalves collected from the study area, recorded a maximum level ranging from 65.2 to 2668.9 Bq/kg in soft tissues and from 1.19 to 15.3 Bq/kg in shells. The bioaccumulation ability in bivalve species with reference to 210 Po was observed to be highly variable

Le paludisme, le tsunami silencieux d'Afrique | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

12 janv. 2011 ... Dans un élan de compassion fort justifié, le monde s'est porté au secours des victimes du tsunami qui a touché récemment la région de l'océan Indien. Mais il ignore qu'un « tsunami silencieux », le paludisme, s'abat sans cesse sur l'Afrique et y fait chaque année plus de 1,5 million de victimes, surtout de ...

Le Peer to Peer: Vers un Nouveau Modèle de Civilisation

Directory of Open Access Journals (Sweden)

Michel Bauwens

2006-06-01

Full Text Available Le « peer to peer » est la dynamique intersubjective caractéristique des réseaux distribués. Le but de cet essai est de montrer qu’il s’agit d’une véritable nouvelle forme d’organisation sociale, apte à produire et échanger des biens, à créer de la valeur. Celle-ci est la conséquence d’un nouvel imaginaire social, et possède le potentiel de devenir le pilier d’un nouveau mode d’économie politique, voire d’un nouveau type de civilisation. Pour cela, nous allons d’abord définir le P2P, décrire en bref ces manifestations, et le différencier d’autres modalités d’échange intersubjectif tel que le marché, la hiérarchie, l’économie du don. Comme principale modalité P2P nous distinguons: Les processus de production P2P, comme troisième mode de production, qui n’est ni géré par un mode hiérarchique ou par l’état, ni répondant à des impératifs de profit ou qui sont modulés par le biais des prix. Les processus de gouvernance P2P, qui gouverne ces processus de production. Les formes de propriété P2P, qui sont destine a empecher l’appropriation prive de cette production pour le commun. Afin d’examiner les characteristiques de cette nouvelle dynamique sociale, nous utilisons la typologie intersubjective de l’anthropologue Alan Page Fisque, qui distingue: 1. l’échange égalitaire (Equality Matching, c..a.d l’economie du don. 2. La relation d’autorité (Authority Ranking tel qu’elle s’exprime dans le mode hierarchique. 3. le marché (Market Pricing. 4. la participation commune (Communal Shareholding. En conclusion, nous examinons les possibilites d’expansion de ce nouveau mode sociale et son insertion dans l’economie capitaliste, en nous nous posons la question: le P2P peut-il etre concu comme alternative sociale et economique aux modeles existants. Abstract: “Peer to peer” is hypothesized as a new social formation with intersubjective dynamics characteristic of distributed

La piraterie sur le web

CERN Multimedia

2002-01-01

Les échanges de toutes sortes sont facilités à l'extrême par le web: des forums, des vidéoconférences, le commerce à distance, ou tout simplement la célérité des courriers électroniques ou la convivialité des chats, tout cela participe de la société de communication. Une certaine partie du monde découvre le nouvel horizon des échanges quasi instantanés, mais... les transactions sur le web sont-elles vraiment s res?

Dans le tourbillon des particules

CERN Document Server

Zito, Marco

2015-01-01

Accélérateurs géants, détecteurs complexes, particules énigmatiques... La physique subatomique peut sembler bien intimidante pour le novice. Et pourtant, qui n a jamais entendu parler du boson de Higgs et du CERN, le laboratoire européen où il a été découvert en 2012 ? Nul besoin d être un spécialiste pour comprendre de quoi il s agit. Aujourd hui, une théorie extraordinairement élégante, le Modèle Standard, décrit tous les résultats des expériences dans le domaine. Trente-sept particules élémentaires et quatre forces fondamentales : c est tout ce dont nous avons besoin pour expliquer la matière et l Univers ! Ce livre, destiné à un large public, raconte sans équations le long parcours qui a abouti au Modèle Standard. Ce parcours, parfois sinueux, a été entamé lorsque les Grecs anciens, et peut-être d autres avant eux, ont imaginé que la matière est composée de petites « billes ». Il faudra attendre plusieurs siècles pour qu on réalise que la matière, à l échelle micros...

Le SRAS, le sida, et la santé publique | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

22 juil. 2011 ... Certaines de ces leçons portent sur les interactions complexes entre la biologie, la culture et le pouvoir. D'autres traitent des moyens de .... HIV prevention policy in China. IDRC-funded research is using mathematical modelling to influence local and national policies in China to reduce HIV transmission.

La science, la littérature, le rituel: le vrai dire et le plus que mentir

Directory of Open Access Journals (Sweden)

Panagiotis Christias

2005-03-01

Full Text Available Le scientifique promet la vérité sans être en mesure d'accomplir sa promesse tandis que l'écrivain promet de mentir mais par son mensonge, il fait plus que mentir. Il ne dit certainement pas la vérité, car la vérité n'est pas sa préoccupation première. Voilà comment nous pouvons résumer les deux attitudes, condamnées à un antagonisme stérile par l'attitude positiviste moderne. Compte tenu donc de l'intention fondatrice de la science, de sa promesse donc originaire et fondatrice, la science doit dire la vérité et rien que la vérité. Ce qui, de l'aveu même de cette même science, est impossible. [...] La littérature se permet de reconstruire des mondes par-delà le vrai et le faux. [...] Un récit littéraire ne demande pas la consécration de la vérité, ne demande pas à être suivi parce que vrai, n'impose rien et n'attend rien. Sa vraie destinée est l'errance et sa vraie conscience est celle de sa dissémination. Celui qui renonce à la prétention de vérité renonce en même temps à la volonté de dominer. Dominer signifie créer un espace de vérité dans lequel celui qui énonce la vérité est le maître légitime de ceux qui sont dans le champ de la conception du monde dont cette vérité est la pierre angulaire.

Inducing the Alternative Oxidase Forms Part of the Molecular Strategy of Anoxic Survival in Freshwater Bivalves

Science.gov (United States)

Yusseppone, Maria S.; Rocchetta, Iara; Sabatini, Sebastian E.; Luquet, Carlos M.; Ríos de Molina, Maria del Carmen; Held, Christoph; Abele, Doris

2018-01-01

Hypoxia in freshwater ecosystems is spreading as a consequence of global change, including pollution and eutrophication. In the Patagonian Andes, a decline in precipitation causes reduced lake water volumes and stagnant conditions that limit oxygen transport and exacerbate hypoxia below the upper mixed layer. We analyzed the molecular and biochemical response of the North Patagonian bivalve Diplodon chilensis after 10 days of experimental anoxia (<0.2 mg O2/L), hypoxia (2 mg O2/L), and normoxia (9 mg O2/L). Specifically, we investigated the expression of an alternative oxidase (AOX) pathway assumed to shortcut the regular mitochondrial electron transport system (ETS) during metabolic rate depression (MRD) in hypoxia-tolerant invertebrates. Whereas, the AOX system was strongly upregulated during anoxia in gills, ETS activities and energy mobilization decreased [less transcription of glycogen phosphorylase (GlyP) and succinate dehydrogenase (SDH) in gills and mantle]. Accumulation of succinate and induction of malate dehydrogenase (MDH) activity could indicate activation of anaerobic mitochondrial pathways to support anoxic survival in D. chilensis. Oxidative stress [protein carbonylation, glutathione peroxidase (GPx) expression] and apoptotic intensity (caspase 3/7 activity) decreased, whereas an unfolded protein response (HSP90) was induced under anoxia. This is the first clear evidence of the concerted regulation of the AOX and ETS genes in a hypoxia-tolerant freshwater bivalve and yet another example that exposure to hypoxia and anoxia is not necessarily accompanied by oxidative stress in hypoxia-tolerant mollusks. PMID:29527172

Inducing the Alternative Oxidase Forms Part of the Molecular Strategy of Anoxic Survival in Freshwater Bivalves

Directory of Open Access Journals (Sweden)

Maria S. Yusseppone

2018-02-01

Full Text Available Hypoxia in freshwater ecosystems is spreading as a consequence of global change, including pollution and eutrophication. In the Patagonian Andes, a decline in precipitation causes reduced lake water volumes and stagnant conditions that limit oxygen transport and exacerbate hypoxia below the upper mixed layer. We analyzed the molecular and biochemical response of the North Patagonian bivalve Diplodon chilensis after 10 days of experimental anoxia (<0.2 mg O2/L, hypoxia (2 mg O2/L, and normoxia (9 mg O2/L. Specifically, we investigated the expression of an alternative oxidase (AOX pathway assumed to shortcut the regular mitochondrial electron transport system (ETS during metabolic rate depression (MRD in hypoxia-tolerant invertebrates. Whereas, the AOX system was strongly upregulated during anoxia in gills, ETS activities and energy mobilization decreased [less transcription of glycogen phosphorylase (GlyP and succinate dehydrogenase (SDH in gills and mantle]. Accumulation of succinate and induction of malate dehydrogenase (MDH activity could indicate activation of anaerobic mitochondrial pathways to support anoxic survival in D. chilensis. Oxidative stress [protein carbonylation, glutathione peroxidase (GPx expression] and apoptotic intensity (caspase 3/7 activity decreased, whereas an unfolded protein response (HSP90 was induced under anoxia. This is the first clear evidence of the concerted regulation of the AOX and ETS genes in a hypoxia-tolerant freshwater bivalve and yet another example that exposure to hypoxia and anoxia is not necessarily accompanied by oxidative stress in hypoxia-tolerant mollusks.

48. Le pavillon Liliane de Stewart

OpenAIRE

Cameron, Christina; Déom, Claudine; Valois, Nicole

2018-01-01

Le pavillon Liliane de Stewart Le pavillon Liliane de Stewart est situé à l’arrière du pavillon Marguerite-d’Youville, qui lui est mitoyen. Il en constitue en quelque sorte un agrandissement, mais il s’en différencie par son plus petit volume (trois étages). Les deux pavillons partagent quelques caractéristiques architecturales, dont le plan angulaire et le revêtement de brique chamois. Le pavillon Liliane de Stewart se distingue cependant par sa fenestration, surtout celle de la façade avant...

Occurrence of potentially pathogenic Vibrio in oysters (Crassostrea gigas and waters from bivalve mollusk cultivations in the South Bay of Santa Catarina

Directory of Open Access Journals (Sweden)

Roberta Juliano Ramos

2014-06-01

Full Text Available Introduction This research aimed to identify and quantify potentially pathogenic Vibrio from different cultivations of bivalve shellfish in the State of Santa Catarina, Brazil, and water regions in the South Bay, as well as correlate the incidence of these microorganisms with the physicochemical parameters of marine waters. Methods Between October 2008 and March 2009, 60 oyster and seawater samples were collected from six regions of bivalve mollusk cultivation, and these samples were submitted for Vibrio counts. Results Twenty-nine (48.3% oyster samples were revealed to be contaminated with one or more Vibrio species. The Vibrio parahaemolyticus and Vibrio vulnificus counts in the samples ranged from < 0.5 log10 Most Probable Number (MPN g–1 to 2.3 log10 MPN g–1 oyster and from < 0.5 log10 MPN g–1 to 2.1 log10 MPN g–1 oyster, respectively. Of the 60 seawater samples analyzed, 44 (73.3% showed signs of contamination with one or more vibrio species. The counts of V. parahaemolyticus and V. vulnificus in the samples ranged from < 0.3 log10 MPN·100mL–1 to 1.7 log10MPN·100mL–1 seawater and from < 0.3 log10 MPN·100mL–1 to 2.0 log10 MPN·100mL–1 seawater, respectively. A positive correlation between V. vulnificus counts and the seawater temperature as well as a negative correlation between the V. parahaemolyticus counts and salinity were observed. Conclusions The results suggest the need to implement strategies to prevent vibrio diseases from being transmitted by the consumption of contaminated bivalve shellfish.

Le cosmos et le lotus confessions d'un astrophysicien

CERN Document Server

Trinh, Xuan Thuan

2011-01-01

Que nous dit vraiment la science sur la nature de l'univers, sur son origine et son avenir ? Par quel mystère le langage mathématique, pure création de l'esprit humain, se révèle-t-il aussi performant pour nous décrire les phénomènes physiques, de l'infiniment petit à l'infiniment grand ? S'il existe un ordre du monde, ce que nous en disent la physique quantique et la théorie de la relativité est-il compatible avec ce qu'enseigne le bouddhisme ? Et que peut-on en conclure concernant notre propre vie ? A ces questions passionnantes et à beaucoup d'autres, le célèbre astrophysicien Trinh Xuan Thuan répond ici d'une façon personnelle, en s'appuyant sur son expérience. Son itinéraire l'a placé d'emblée à la confluence de trois cultures : issu d'une famille de lettrés vietnamiens imprégnée de traditions bouddhiste et confucéenne, il a reçu une éducation à la française puis une formation scientifique à l'américaine. Une telle richesse de points de vue lui permet d'apporter, non pas de...

Accessibilité aux emplois en France : le rôle de la distance à la ville

Directory of Open Access Journals (Sweden)

Mohamed Hilal

2004-12-01

Full Text Available L'objet de cet article est de modéliser les niveaux d’accessibilité potentielle aux emplois des communes françaises selon le rôle de la distance à la ville. Pour ce faire, nous présentons, tout d’abord, un modèle d’accessibilité et la méthode mise en œuvre pour calculer de façon systématique, à partir des données du réseau routier, une matrice des plus courts chemins, mesurés en temps, entre les communes françaises. Ensuite, dans la deuxième partie, ces distances sont intégrées dans le modèle d’accessibilité retenu afin de mesurer la disponibilité potentielle aux emplois selon la distance au pôle urbain le plus proche et selon les principales catégories d’espace du zonage en aires urbaines et de son complément rural. Enfin, la mesure d’accessibilité potentielle est comparée à plusieurs mesures d’accessibilité empirique.

Le fictif et le réel dans L’Empereur et l’assassin de Chen Kaige

OpenAIRE

Giafferri, Xiaomin

2008-01-01

Comme tout texte historique littéraire refait l’Histoire en la manipulant, le récit filmique est doublement mensongère du fait de sa double représentation : le décor et les acteurs représentent une situation qui est la fiction, et le film lui-même représente sous forme d’images juxtaposées cette première représentation. Sans vouloir faire la part du réel et de l’imaginaire, le présent travail tente de montrer comment, dans le film L’empereur et l’assassin de Chen Kaige, l’illusion de l’authen...

pour le trimestre qui a pris fin le 30 juin 2013

International Development Research Centre (IDRC) Digital Library (Canada)

Office 2004 Test Drive User

30 juin 2013 ... Conseil des gouverneurs du CRDI. Le mandat des gouverneurs suivants a pris fin le 27 mai 2013 : Margaret Biggs, d'Ottawa, en Ontario;. Faith Mitchell, de Washington, aux États-Unis; Elizabeth Parr-Johnston, de Chester Basin, en Nouvelle-Écosse; Gordon Shirley, de Kingston, en Jamaïque; l'honorable ...

Le droit, l'économie et le fondamental

OpenAIRE

Gérard Farjat

2005-01-01

MAITRE Grégory, préf. MUIR WATT Horatia, La Responsabilité civile à l’épreuve de l’analyse économique du droit, Paris, L.G.D.J., coll. Droit &Économie, 2005,315 p. LE TOURNEAU Philippe, L’Éthique des affaires et du management au XXIe siècle, Paris, Dalloz, Paris, Dunod, 2000,269 p. DELMAS-MARTY Mireille, Le Relatif et l’universel : les forces imaginantes du droit, Paris, Seuil, coll. La Couleur des idées, 2004,440 p. FRISON-ROCHE Marie-Anne, BONFILS Sébastien, Les Grandes Questions du droit é...

Le FIVB annonce le financement de huit autres projets | CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

5 avr. 2018 ... Découvrez les derniers récents projets soutenus par le Fonds d'innovation en matière de vaccins pour le bétail : Maladie de Newcastle · Pleuropneumonie contagieuse caprine – cowdriose · Plateforme de modification génétique CRISPR/cas9 · Entérotoxémie, la bactérie Pasteurella et la fièvre de la vallée ...

pour le trimestre qui a pris fin le 30 septembre 2016

International Development Research Centre (IDRC) Digital Library (Canada)

Office 2004 Test Drive User

30 sept. 2016 ... Le CRDI finance des travaux de recherche appliquée ... internationales dʼinformation financière (normes IFRS). ..... voie de développement et sur la mise en oeuvre des connaissances scientifiques, techniques et autres en vue du .... Les accords expirent à des dates différentes, et le dernier prend fin en.

Le barrage des trois Gorges (Chine

Directory of Open Access Journals (Sweden)

Luc Merchez

1999-09-01

Full Text Available Le barrage des Trois Gorges, en construction sur le Yangzijiang, sera le plus grand barrage au monde. Le gigantisme du projet et sa médiatisation croissante en Occident permettent d'en saisir les enjeux environnementaux et humains. On analyse les grandes caractéristiques du projet et ses conséquences premières avant d'aborder le travail de recherche de l'équipe SIG de l'IGA de Grenoble qui vise à préparer la relocalisation de plus d'un million d'habitants, et à modéliser les impacts démographiques et sociaux.

Le rôle de l'IL6 dans le cancer du foie lié à l'hépatopathie métabolique

International Development Research Centre (IDRC) Digital Library (Canada)

Le cancer du foie est souvent mortel. Il n'existe que très peu d'options de traitement, et il s'agit de l'un des cancers dont l'incidence augmente dans le monde entier. L'obésité ou les maladies métaboliques (comme le diabète et la stéatose hépatique) constituent des facteurs de risque du cancer du foie qui sont mal compris.

Rapport financier trimestriel pour le trimestre qui a pris fin le 30 ...

International Development Research Centre (IDRC) Digital Library (Canada)

Sophie Comeau

30 sept. 2017 ... Régi par la Loi sur le Centre de recherches pour le développement international ... forme des leaders dans les secteurs de l'administration publique, de la .... Plus des trois quart du manque à gagner prévu de 11,6 millions.

Nicolas Michel, Une économie de subsistances. Le Maroc précolonial, IFAO, Le Caire, 1997.

Directory of Open Access Journals (Sweden)

Sylvie Denoix

2004-11-01

Full Text Available Le titre de cet ouvrage peut apparaître paradoxal si l'on considère, comme le rappelle Nicolas Michel, que le Maroc, dès avant le XIXe siècle, était inséré dans une économie marchande internationale "faisant circuler dans tout le pays produits et espèces monétaires". En fait, les produits de première nécessité échappent au grand négoce et font plutôt l'objet d'un troc, d'un échange contre services, hors système monétaire. Néanmoins, dans un souci de rigueur méthodologique, l'auteur nous garde...

Le CRDI en Égypte

International Development Research Centre (IDRC) Digital Library (Canada)

afin d'y favoriser la croissance et le développement. Il en résulte des solutions locales, novatrices et durables, qui offrent des choix aux personnes qui en ont le plus besoin et font changer les choses. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9. 1012 alexandrie.

Scientific opinion on the risks for public health related to the presence of tetrodotoxin (TTX) and TTX analogues in marine bivalves and gastropods

DEFF Research Database (Denmark)

Petersen, Annette

Tetrodotoxin (TTX) and its analogues are produced by marine bacteria and have been detected in marine bivalves and gastropods from European waters. The European Commission asked EFSA for a scientific opinion on the risks to public health related to the presence of TTX and TTX analogues in marine...... bivalves and gastropods. The Panel on Contaminants in the Food Chain reviewed the available literature but did not find support for the minimum lethal dose for humans of 2 mg, mentioned in various reviews. Some human case reports describe serious effects at a dose of 0.2 mg, corresponding to 4 μg/kg body...... weight (bw). However, the uncertainties on the actual exposure in the studies preclude their use for derivation of an acute reference dose (ARfD). Instead, a group ARfD of 0.25 μg/kg bw, applying to TTX and its analogues, was derived based on a TTX dose of 25 μg/kg bw at which no apathy was observed...

Le CRDI en Indonésie

International Development Research Centre (IDRC) Digital Library (Canada)

l'État dans l'île de Java. Soutenu par le CRDI, l'institut Lembaga Alam Tropika Indonesia. (ou LATIN) a conçu un modèle de cogestion des forêts qui met à contribution les collec- tivités et le gouvernement dans trois dis- tricts. Ainsi, les agriculteurs disposent d'un meilleur accès aux ressources de la forêt. Évaluation des ...

Le shopping mall : un modèle pour la construction de la ville ?

OpenAIRE

Daniau, Anaïs

2017-01-01

Après avoir montré à quel point le renouvellement du concept de shopping mall s’était inspiré de la ville, le présent article souhaite symétriser l’analyse de cette relation en décrivant la manière dont la gestion des centres urbains emprunte au fonctionnement des centres commerciaux pour se réinventer. Cette référence croissante au centre commercial comme modèle d’efficacité par les gestionnaires de centre-ville révèle selon nous l’existence de processus plus larges touchant nos centres-vill...

The quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897 – another Ponto-Caspian dreissenid bivalve in the southern Baltic catchment: the first record from the Szczecin Lagoon

Directory of Open Access Journals (Sweden)

Adam Woźniczka

2016-04-01

Full Text Available In 2014, a non-indigenous dreissenid bivalve, the quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897 was for the first time recorded in the Szczecin Lagoon. This was also the first record of the species in the Baltic Sea catchment. The quagga mussel was found to accompany the zebra mussel (Dreissena polymorpha, a non-indigenous bivalve already firmly established in the Lagoon. As indicated by the new immigrant's estimated abundance (4000.0 ± 355.44 ind. m−2 and the zebra mussel to quagga mussel abundance ratio (about 60:40, the immigration of D. rostriformis bugensis to the Lagoon can be regarded as successful. The quagga mussel has already formed a strong and reproducing population which co-occurs with that of the zebra mussel in the area.

Rapport financier trimestriel pour le trimestre qui a pris fin le 31 ...

International Development Research Centre (IDRC) Digital Library (Canada)

Sophie Comeau

31 déc. 2017 ... Régi par la Loi sur le Centre de recherches pour le développement international ... optimiser les retombées; forme des leaders dans les secteurs de ... Centre dans ce domaine, et a animé une table ronde avec trois des quatre ...

Le partenariat mondial sur les données ouvertes pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Les données ouvertes favorisent le changement. Au Brésil, au Népal et au Nigeria, certaines personnes utilisent les données publiquement accessibles sur le budget gouvernemental pour repérer et combattre la corruption. Des analystes de données et des développeurs en TI d'autres pays en développement améliorent ...

pour le trimestre qui a pris fin le 30 septembre 2012

International Development Research Centre (IDRC) Digital Library (Canada)

acray

30 sept. 2012 ... recommande de lire ce rapport en parallèle avec les états financiers non audités (à la page 9). L'information et les .... développement ont augmenté de 56,9 % par rapport au même trimestre de l'exercice 2011-2012 ..... IFRS) telles que publiées par le Conseil des normes comptables internationales (CNCI).

Les pôles de compétitivité : le recours au modèle des clusters ?

Directory of Open Access Journals (Sweden)

Jean Bouinot

2007-03-01

Full Text Available Introduction : définition d’un cluster En novembre 2004, le gouvernement a lancé un appel d’offre pour structurer des pôles de compétitivité que les praticiens français n’hésitent pas à qualifier de cluster, littéralement un rassemblement du type « bouquet de fleurs ». Pour une définition théorique on peut s’appuyer sur une comparaison avec le modèle du district industriel italien (MDII. Le district est spécialisé dans un produit donné (chaussures de sport à Montebelluna, le leader mondial e...

Luther contre le protocole de Kyoto ou le retour des « indulgences ».

Directory of Open Access Journals (Sweden)

Bernard Jouve

2005-05-01

Full Text Available Le 16 février 2005 a marqué la mise en œuvre du Protocole de Kyoto. En fait, depuis l’annonce par la Russie, le 25 octobre 2004, de sa décision de ratifier ce protocole, l’affaire était entendue. Menacé depuis le refus des États-Unis, l’un des plus grands pollueurs de la planète, de ne pas le ratifier pour des raisons purement économiques alors que ce pays produit à lui seul 40 % des gaz à effet de serre ( ges , l’accord survenu à Kyoto en 1997 est enfin entériné et ...

Le paludisme, le tsunami silencieux d'Afrique | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

12 janv. 2011 ... Dans un élan de compassion fort justifié, le monde s'est porté au secours des victimes du tsunami qui a touché récemment la région de l'océan Indien. Mais il ignore qu'un « tsunami silencieux », le paludisme, s'abat sans cesse sur l'Afrique et y fait chaque année plus de 1,5 million de victimes, surtout de ...

Sauver le café | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

D'un tiroir de la collection entomologique de Cenicafé, où sont conservés 38 000 spécimens, Álvaro Gaitán extrait le coupable, un minuscule insecte brunâtre qui a fait perdre à lui seul un demi-milliard de dollars par an à l'industrie du café dans les dernières années. Le scolyte du caféier (la broca, en espagnol) se nourrit ...

Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

Energy Technology Data Exchange (ETDEWEB)

Foulquier, L.; Bovard, P.; Grauby, A. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1966-07-01

l'animal total. Cette etude comparee a celles deja effectuees par d'autres auteurs permet de degager des idees generales sur le mode et la capacite de fixation du {sup 137}Cs par les lamellibranches. (auteur)

Le continu contre l'espace

Science.gov (United States)

Salanskis, Jean-Michel

Disons pour conclure que, en tout état de cause, la façon de concevoir philosophiquement le conflit du continu et de l'espace que nous avons trouvée chez Hegel n'est pas homogène avec le style et les modalités de la pensée mathématique: 1) d'une part, le lien classique, le lien de référence entre continu et espace en mathématiques n'est pas que l'espace serait premier et privé de pensée, et le continu second, venant dissoudre l'espace en apportant la qualité, l'infini et la pensée, mais tout au contraire, il consiste en ce que l'espace est fondé sur l'abîme infinitaire du continu ; 2) d'autre part, l'éventuel divorce entre l'espace et le continu dans l'aire mathématique n'est pas celui d'une réflexivité purement conceptuelle du continu avec un positivisme géométrique, n'équivaut pas à une rupture disciplinaire ; il est plutôt le symptôme de la dérive d'une herméneutique à l'égard d'une autre, au sein d'un continent juridique commun définissant la discipline (la mathématique ensembliste), cette dérive pouvant, à la limite, induire une refonte de ce sol juridique, sans que jamais il soit question pour autant de nier l'unité des mathématiques, à comprendre ici comme l'unité ultime de responsabilité de la communauté mathématique à l'égard des trois questions Qu'est-ce que l'espace?”, “Qu'est-ce que le continu?” et “Qu'est-ce que l'infini?”.

Le surpoids, l'obésité et le contrôle glycémique chez les diabétiques ...

African Journals Online (AJOL)

utilisation et du stockage des sucres apportés par l'alimentation, sa prise en charge est ... l'organisation mondiale de santé (OMS), Le contrôle glycémique a été effectué par l'analyse sanguine de l'Hémoglobine glycosylée et de la Glycémie à jeun.

Hepatitis A and E Viruses in Wastewaters, in River Waters, and in Bivalve Molluscs in Italy.

Science.gov (United States)

Iaconelli, M; Purpari, G; Della Libera, S; Petricca, S; Guercio, A; Ciccaglione, A R; Bruni, R; Taffon, S; Equestre, M; Fratini, M; Muscillo, M; La Rosa, Giuseppina

2015-12-01

Several studies have reported the detection of hepatitis A (HAV) and E (HEV) virus in sewage waters, indicating a possibility of contamination of aquatic environments. The objective of the present study was to assess the occurrence of HAV and HEV in different water environments, following the route of contamination from raw sewage through treated effluent to the surface waters receiving wastewater discharges . Bivalve molluscan shellfish samples were also analyzed, as sentinel of marine pollution. Samples were tested by RT-PCR nested type in the VP1/2A junction for HAV, and in the ORF1 and ORF2 regions for HEV. Hepatitis A RNA was detected in 12 water samples: 7/21 (33.3%) raw sewage samples, 3/21 (14.3%) treated sewage samples, and 2/27 (7.4%) river water samples. Five sequences were classified as genotype IA, while the remaining 7 sequences belonged to genotype IB. In bivalves, HAV was detected in 13/56 samples (23.2%), 12 genotype IB and one genotype IA. Whether the presence of HAV in the matrices tested indicates the potential for waterborne and foodborne transmission is unknown, since infectivity of the virus was not demonstrated. HEV was detected in one raw sewage sample and in one river sample, both belonging to genotype 3. Sequences were similar to sequences detected previously in Italy in patients with autochthonous HEV (no travel history) and in animals (swine). To our knowledge, this is the first detection of HEV in river waters in Italy, suggesting that surface water can be a potential source for exposure .

Biomarkers of metabolism disturbance in bivalve molluscs induced by environmental pollution with processed by-products of oil

Directory of Open Access Journals (Sweden)

E. V. Sukharenko

2017-05-01

Full Text Available Processed by-products of oil are the most common pollutants in all river and sea water. The increase in oxidative stress in bivalve molluscs was studied in both tissues of the hepatopancreas and the gill. The model for artificial treatment with processed by-products of oil was performed in a laboratory experiment with the river mollusc Dreissena polymorpha Pallas, 1771. The exposure of the molluscs over 28 days to mazut 50 mg/l induced significant increase of both final product of lipid peroxidation (LPO and antioxidant enzime activity. A significant increase in LPO was observed in the hepatopancreas and gill of D. polymorpha treated with mazut compared to the control group. Antioxidant enzyme activity of cartalase, supeoxide dismutase, glutathione reductase and glutathione-S-transferase showed a greater increase (by almost 1.5 times in the hepatopancreas than in the gill of D. polymorpha. A similar LPO growth and modulation of antioxidant enzyme activity were determined in the hepatopancreas and gill of the mussel Mytilus galloprovincialis Lamarck, 1879 collected in an area polluted with resins, hydrocarbons and asphaltenes, Donuzlav lake in the Kerch gulf. Varied cellular reactivation of the antioxidant enzyme system in the hepatopancreas rather than the gill was observed in both kinds of mollusc Dreissena and Mytilus. The obtained results are evidence of the higher sensitivity of the hepatopancreas cells of bivalve molluscs to organic pollutants compared to the gill cells.

Rapport financier trimestriel pour le trimestre qui a pris fin le 31

International Development Research Centre (IDRC) Digital Library (Canada)

Sophie Comeau

31 déc. 2011 ... politiques, de chercheurs et de collectivités de par le monde. ..... qui a été choisi à l'issue d'un processus de recrutement mené ... Les bureaux régionaux constituent une ressource stratégique et un élément clé du modèle de.

Rapport financier trimestriel pour le trimestre qui a pris fin le 31

International Development Research Centre (IDRC) Digital Library (Canada)

Office 2004 Test Drive User

31 déc. 2016 ... Le CRDI finance des travaux de recherche appliquée ... développement international (le Centre) et lʼévolution de la ...... voie de développement et sur la mise en oeuvre des connaissances scientifiques, techniques et autres en vue du .... vertu d'accords de contribution conclus avec des bailleurs de fonds.

Bibliographie de l’île de Clipperton – Île de La Passion (1711-2005)

OpenAIRE

Jost, Christian

2008-01-01

L’île de Clipperton, baptisée « Île de La Passion » par ses découvreurs français en 1711, porte pourtant le nom d’un pirate anglais. Malgré les très courtes périodes d’occupation qu’elle connut au début du XXe siècle et dans les années 1960, son histoire est jalonnée de nombreux écrits. Son intérêt scientifique sur le plan des études environnmentales et les enjeux économique et géopolitique récemment renouvelés conduisent l’auteur à publier ici cette bibliographie de plus de trois cent cinqua...

Lutter contre le paludisme sans DDT

International Development Research Centre (IDRC) Digital Library (Canada)

Nancy Minogue

La participation de la collectivité aux stratégies de contrôle, une surveillance ... Le contrôle de la maladie passe par une meilleure gestion de l'environnement. En vertu de ... de la santé humaine, ou écosanté, est un processus dynamique qui.

PERFORMANCE ET RESTRUCTURATION: LE CAS SAÏDAL ...

African Journals Online (AJOL)

performance de SAÏDAL suite à sa restructuration débutée en 1997. Le concept de ... millions d'actions. Du point de vue du management, SAÏDAL adopte le tableau de .... Méthodes et Pratiques de la Performance : Le Guide du Pilotage. ... performance des entreprises, Kaplan et Norton proposèrent le tableau de bord ...

Le Valais et ses Reines

Directory of Open Access Journals (Sweden)

Alberto Campi

2012-06-01

Full Text Available Combat de ReinesAu premier plan (la corde dans la main, un propriétaire de vaches. Dans l'arène se trouve le rabatteur. Les Reines sur la photo sont des reines de première catégorie (ainsi que le montre le « I » sur leur cuisse .Dimanche 6 mai 2012, « Schakira », la vache numéro 42, a gagné, non sans polémique, le titre de Reine. Elle peut donc être considérée comme la Reine des Reines, titre qu’elle a gagné en se battant contre ses rivales dans différents combats, qui ont commencé pour Sch...

Quand le lait devient enjeu social : le cas de la société peule dans le Séno (Burkina Faso

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Madina Querre

2003-09-01

Full Text Available L’intérêt pour le « lait » en tant que sujet de recherche est issu, ici, de questionnements autour de l’allaitement en tant que facteur de transmission du VIH. En effet, la transmission du VIH par l’allaitement représente un important problème de santé publique dans les pays du Sud. La mise en place des programmes de prévention reste un problème complexe qui touche divers domaines dont une partie concerne directement notre discipline, étant d’ordre social et culturel. Les perceptions qui valorisent l’allaitement maternel sont très ancrées dans la plupart des cultures « tradi­tionnelles », mettant en valeur celles du lait. Le lait prend en effet dans la société peule une valeur qui va au-delà de la simple question de l’allaitement, étant présent au cœur même de la structure socio-économique. C’est cet aspect qui constituera le propos de cet article.Le terme Kossam, qui désigne le lait, signifie « ce qui est meilleur ». A la base de l’organisation socio-économique peule, son exploitation révèle une originalité particulière concernant les femmes : c’est le lait qui donne aux femmes la possibilité d’une émancipation sociale et économique. En effet, tel que cela sera développé dans cet article, le lait de vache est la propriété de la femme dès l’instant où elle est mariée ; elle peut alors en disposer selon ses intérêts pour la consommation et/ou la commercialisation. Elle peut donc avoir une certaine marge de liberté dans ses actions sans être sous la tutelle complète de son époux. Le fait même qu’elle en soit propriétaire fait référence à un fonctionnement et à une représentation sociale spécifiques.Le lait et sa productrice, la vache, sont au cœur du fonctionnement socio-économique peul. Le lait est considéré comme étant à la base de l’alimentation ; même si dans les faits l’alimentation est aussi organisée autour du mil. Aussi, envisager le

Le vernis des apparences

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Grazia Nicosia

2010-04-01

Full Text Available Le but de cet article est de comprendre l’incidence sémiotique du nettoyage d’un tableau ainsi que la résultante cognitive induite sur l’observateur. Cette étude confronte l’analyse des phénomènes visuels engendrés par le jaunissement du vernis et son retrait, à des entretiens réalisés à dessein. Le retrait d’un vernis jauni change considérablement l’image. L’heure, le climat, la saison et l’activité même des personnages s’en trouvent ainsi modifié. La patine peut être perçue, soit comme un obstacle à l’exploration, soit pour ceux qui l’apprécient, comme le medium d’une relation plus intime entre l’œuvre et l’observateur.The purpose of this article is to understand the semiotic impact of the cleaning of a painting and the cognitive effects induced on the observer. This study analyses conjointly the visual phenomenon generated by yellowing varnish and its removal and controlled interviews of observers.The removal of yellowing varnish modifies considerably the perception of the picture. Daytime, climate, season and characters activities are modified. The patina may be perceived either as an obstacle to the painting exploration, or, for those who appreciate it, as a medium for a closer relationship between the painting and the observer.

Le corps dans l'Antiquité

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Sophie Lalanne

2008-06-01

Full Text Available Ouvrages générauxLaqueur Thomas, La fabrique du sexe. Essai sur le corps et le genre en Occident, trad. fr., Paris, Gallimard, 1992.Feher Michel, Naddaff Ramona, Tazi Nadia, Fragments for a History of the Human Body, 3 volumes, New York, Zone Books, 1989.Le Corps dans l’AntiquitéBodiou Lydie, Frère Dominique, Mehl Véronique dir., L’expression des corps. Gestes, attitudes, regards dans l’iconographie antique, Rennes, Presses Universitaires de Rennes, 2006.Bonnard Jean-Baptiste, Le complexe de ...

La filière d’oignon d’été dans le Saïs au Maroc : la place et le rôle des intermédiaires de la commercialisation

Directory of Open Access Journals (Sweden)

Caroline Lejars

2014-11-01

Full Text Available Les agriculteurs dépendent souvent, pour la commercialisation de leur produit, d'un réseau complexe d'intermédiaires privés. Dans les pays en développement, ces intermédiaires de la vente sont souvent accusés de réaliser des profits excessifs et d’être responsables des énormes écarts entre le prix de vente au champ et le prix payé par le consommateur. En s’appuyant sur l’étude de la filière oignon d’été dans le Saïs au Maroc, cet article analyse le rôle de ces réseaux d'intermédiaires, et la répartition des coûts et de la marge bénéficiaire le long de la chaine de production et de commercialisation. On montre ainsi que cette filière crée un grand nombre d'emplois en aval de la production, que ce soit pour la collecte, le stockage, le transport ou la vente. La part de la marge bénéficiaire revenant à l’ensemble des intermédiaires est supérieure à celle revenant aux producteurs, ce qui entraine effectivement une importante différence de prix entre le prix de vente et le prix du marché. Même si les profits et les rôles des intermédiaires sont très variables, certains des acteurs intermédiaires, notamment les détaillants et les revendeurs en gros, récupèrent des marges bien supérieures à celles des agriculteurs. L’organisation des producteurs autour de zones de stockage et d’activités de commercialisation permettrait de limiter le nombre d’intermédiaires, d’accroitre le profit des agriculteurs et de modifier les rapports de négociations souvent asymétriques entre agriculteurs et commerçants.

Le rôle des chefs traditionnels en Afrique | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

14 juil. 2011 ... Se fondant sur ces expériences, Ray, présentement professeur de sciences politiques à l'Université de Calgary, a mené un nouveau projet sur le rôle des chefs traditionnels dans la gouvernance locale en Afrique. Bien qu'il soient souvent ignorés par les organismes de développement international, les ...

Le nouveau modèle québécois axé sur la gouvernance

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Jeffrey Roy

2002-10-01

Full Text Available L'article soutient qu'il a bien eu un modèle québécois de développement, mais il est devenu inefficace et remis en question. Ce modèle se distinguait par son interventionniste étatique dynamique et par la constitution d'alliances entre les différents partenaires sociaux. Mais les fondements d'un modèle performant tels que l'étatisme et le nationalisme civique sont devenus empreints de faiblesses et d'insuffisances que l'utilisation du concept de gouvernance permet d'identifier. Le concept se définit comme étant « la coordination efficace de l'ensemble des activités d'une entité socio-économico-politique quand les ressources, le pouvoir et l'information sont vastement distribués ». Malgré l'inefficacité décrite, il est possible de repenser le modèle québécois de développement par la construction des communautés qui s'appuie sur la régionalité et la socialité. Finalement, le renouveau s'appuierait sur une stratégie de-gouvernance pour un meilleur usage de l'intelligence collective et des cités-régions intelligentes.The article supports that it indeed had a Quebecois model of development, but it became ineffective and questioned. This model distinguished itself by his(her dynamic state interventionist and by the constitution of alliances among the various social partners. But the foundations of a successful model such as the state control and the civil nationalism became printed by weaknesses and by incapacities which the use of the concept of governance allows to identify. The concept defines itself as being « the effective coordination of all the activities of an entity « socio-économico-politique » when the resources, the power and the information are distributed spaciously » Meanwhile the described ineffectiveness, it is possible to rethink the Quebecois model of development by the construction of the communities which leans on the regionality and the sociality. Finally, the flourish would lean on a strategy

LE CORBUSIER: CONCURSOS Y PALACIOS / Le Corbusier: competitions and palaces

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Fernando Zaparaín Hernández

2012-11-01

Full Text Available RESUMEN Cuando Le Corbusier ya había pasado de los cuarenta años se enfrentó a dos concursos internacionales: el Palacio de las Naciones en Ginebra (1926–31 y el Palacio de los Soviets en Moscú (1931–32 con los que intentaba acceder a grandes encargos de estado con mayor escala urbana en los que poner a prueba su ideario moderno sobre arquitectura y urbanismo. En ambos casos estuvo entre los vencedores pero por conveniencia e indecisión, los poderes políticos optaron por soluciones academicistas. Al conocer las decisiones definitivas, Le Corbusier y todos sus contactos del Movimiento Moderno orquestaron diversas polémicas ante los medios de comunicación y los gobernantes por entender que el progreso se veía lastrado por el triunfo de propuestas reaccionarias. Mediante el estudio de la correspondencia con personas particulares como Moser, Giedion, Colly o Stonorov, conservada en la Fundación Le Corbusier, se analizan las relaciones y el tono ideológico en torno a aquellas protestas. En esos textos quedan reflejados los principales rasgos que caracterizan la modernidad como su internacionalización, la seguridad en la propia misión, la defensa de lo nuevo o el método dialéctico. SUMMARY When Le Corbusier had already passed the age of forty he confronted two international competitions: the Palais des Nations in Geneva (1926–1931 and the Palace of the Soviets in Moscow (1931–32, with which he attempted to access large state commissions, with greater urban scale, in which to test his ideas about modern architecture and urbanism. In both cases he was among the winners, but through convenience and indecision the political powers opted for solutions from academicians. Upon knowing the final decisions, Le Corbusier and all his contacts in the Modern Movement orchestrated several controversies with the media, and the people in power, to convey that progress seemed burdened by the triumph of reactionary proposals. The relationships

Le rôle des associations  dans la médiation en archéologie

OpenAIRE

Sence, Christophe

2014-01-01

Le milieu associatif est connu en France pour son dynamisme et sa réactivité. Il en va de même en archéologie, notamment dans le domaine de la médiation. Si le public ignore bien souvent qu’une association se cache derrière le lieu qu’il vient de visiter, nombreux sont les sites archéologiques, toutes périodes confondues, dont la mise en valeur est entièrement assumée par une telle structure. Dans ce cadre, tout est envisageable, de la simple ouverture pendant les Journées européennes du patr...

Construire les stratégies avec le Balanced Scorecard:vers une approche interactive du modèle de Kaplan et Norton

OpenAIRE

Gérald Naro; Denis Travaillé

2010-01-01

(VF)L’objectif de cet article est de confronter le Balanced Scorecard avec le modèle des leviers de contrôle de Simons (1995) et de discuter de son rôle dans les différentes phases du processus stratégique. Nous privilégions une représentation du BSC comme outil de contrôle interactif. Notre recherche est fondée sur une méthodologie longitudinale de type recherche action à partir de l’étude de deux cas. Les résultats montrent que le BSC crée un processus de construction collective favorisant ...

L’économie politique du désir dans le rituel et le militantisme au SriLanka

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Wim Van Daele

2013-03-01

Full Text Available Le désir est au cœur des interactions complexes entre le développement et la religion. Cet article examine ses différentes expressions, comme étant une des préoccupations fondamentales de nombreuses religions, qui motivent à la fois le développement et les alternatives au développement. Au SriLanka, face au changement social, la forme néolibérale et mondialisée du développement est comprise et réinterprétée à travers des idiomes et des formations locales du désir. L’économie néolibérale cultive le désir et mène à un accroissement présumé de la présence des preta (fantômes affamés et avides qui se manifestent parfois au moment de la mort d’une personne. Les fantômes affamés, en tant que formations fétichisées du désir, trouvent un écho chez les consommateurs et les entrepreneurs, qui montrent unappétit insatiable vis-à-vis d’une richesse matérielle en constante croissance. Ainsi, l’apaisement ritualisé des fantômes affamés et le militantisme social de groupes tels que le Movement for National Land and Agricultural Reform (MONLAR sont clairement liés par leur préoccupation mutuelle face à l’insécurité existentielle des êtres humains et non humains, causée par un désir excessif et déséquilibré. L’action rituelle et le militantisme social divergent toutefois dans la formulation explicite de leurs préoccupations spécifiques concernant le désir. Le rituel matérialise et condense l’angoisse liée au désir, alors que le militantisme social décrit la fétichisation du désir en termes économiques, politiques et scientifiques plus abstraits.

Juan Goytisolo: Le soi, le monde et la création littéraire

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Pablo Romero Alegría

2010-01-01

Full Text Available Reseña de la obra: Yannick Llored. Le soi, le monde et la création littéraire. Presses Universitaires du Septentrion. Villeneuve d’Ascq (Francia. 2009. 421 págs. ISBN: 978-2-75740-0089-0

Le Projet d’Ole Lando sur les Contrats

DEFF Research Database (Denmark)

Holle, Marie-Louise

2017-01-01

En 2016 le projet de recherche le plus important jusqu’à présent sur le droit nordique des contrats a pris fin et un livre, de presque 400 pages, en a marqué l’aboutissement. Le résultat du projet est un « restatement » tel qu’il existe aux États-Unis. Le Restatement porte sur les règles et les...

Le point sur le sida, l'alimentation et la nutrition | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

14 oct. 2010 ... Selon le Programme alimentaire mondial (PAM), 22 des 30 pays à risque élevé ayant besoin d'une aide alimentaire extérieure se trouvent en Afrique subsaharienne, où de nombreux États sont aux prises avec une grave épidémie de sida. Étant donné que le VIH touche les travailleurs dans la force de ...

Le fictif et le réel dans L’Empereur et l’assassin de Chen Kaige

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Xiaomin Giafferri

2008-12-01

Full Text Available Comme tout texte historique littéraire refait l’Histoire en la manipulant, le récit filmique est doublement mensongère du fait de sa double représentation : le décor et les acteurs représentent une situation qui est la fiction, et le film lui-même représente sous forme d’images juxtaposées cette première représentation. Sans vouloir faire la part du réel et de l’imaginaire, le présent travail tente de montrer comment, dans le film L’empereur et l’assassin de Chen Kaige, l’illusion de l’authenticité s’établit à travers les mécanismes de la fictionnalisation de l’Histoire. L’observation de leur manifestation est amenée à considérer deux axes principaux : l’organisation du récit et la mise en scène des personnages.

Le point sur le sida, l'alimentation et la nutrition | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

agriculture et l'alimentation ( FAO ), Stuart Gillespie a passé six mois à étudier le lien entre le VIH/sida et la sécurité alimentaire. Il a vite compris que l'épidémie risquait d'avoir, à long terme, des répercussions désastreuses sur la ...

Le FIE 2008 fait avancer le cadre écobiosocial de l'OMS | CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

10 mai 2011 ... Le Programme spécial de recherche et de formation concernant les maladies tropicales (TDR) de l'OMS a élaboré le concept du champ « écobiosocial », qui combine les perspectives écologiques, biologiques et sociales « pour mieux comprendre la dynamique des maladies infectieuses à transmission ...

Le vase de Pandore

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Nicola Panichi

2000-06-01

Full Text Available Il s’agit ici de suivre les stratégies discursives par lesquelles Érasme situe sa Lingua sous le patronage symbolique de deux mythes des plus opératoires à la Renaissance : le vase de Pandore et la tour de Babel, tous deux verrouillant le texte, l’un en guise d’incipit, l’autre d’explicit, dans un dialogue où chacun use de l’autre pour renforcer les significations et instaurer le régime sémantique du texte, tant linguistique qu’éthique. Ce sont ces jeux complexes entre différents niveaux de discours dont dépend le sens ultime de l’œuvre que cet article s’attache à saisir.Se trata de seguir aquí las estrategias discursivas mediante las cuales Erasmo sitúa su Lingua bajo el dominio simbólico de dos de los mitos más funcionales del Renacimiento: el vaso de Pandora y la torre de Babel, los cuales limitan el texto, uno a modo de íncipit, otro de excipit, en un diálogo en el que se valen el uno del otro para reforzar los significados y establecer el régimen semántico del texto, tanto lingüístico como ético. Son esos juegos complejos entre diferentes niveles de discurso, de los que depende el sentido último de la obra, que este artículo intenta captar.

Le rôle de l'information en droit des entreprises en difficulté

OpenAIRE

Ould Eba, Moussa

2013-01-01

L’information est un moyen de gestion fiable et une garantie indispensable pour la protection des intérêts des acteurs de l’activité économique. Elle joue un rôle important dans la prévention et le traitement des difficultés des entreprises. En effet, à la lumière des informations comptables, financières et sociales, les dirigeants peuvent prévenir les difficultés et prendre les décisions adaptées à la situation de l’entreprise. Toutefois, en cas de procédures collectives, le besoin de protec...

Le cerveau sous effet placebo

OpenAIRE

Touzet , Claude

2017-01-01

International audience; Comment le fait de croire qu’on nous injecte de la morphine (alors qu’il s’agit de sérum physiologique) peut-il faire disparaître la douleur ? Investigation sur le cerveau sous placebo.

pour le trimestre qui a pris fin le 31 décembre 2013

International Development Research Centre (IDRC) Digital Library (Canada)

Sophie Comeau

31 déc. 2013 ... IFRS 9 – Instruments financiers. Le CNCI a l'intention de remplacer la norme IAS 39 – Instruments financiers : comptabilisation et évaluation par la norme IFRS 9. La nouvelle norme guide la classification, la comptabilisation, la décomptabilisation et l'évaluation des actifs et des passifs financiers. Le Centre ...

The mismatch between bioaccumulation in field and laboratory environments: Interpreting the differences for metals in benthic bivalves

International Nuclear Information System (INIS)

Belzunce-Segarra, Maria J.; Simpson, Stuart L.; Amato, Elvio D.; Spadaro, David A.; Hamilton, Ian L.; Jarolimek, Chad V.; Jolley, Dianne F.

2015-01-01

Laboratory-based bioaccumulation and toxicity bioassays are frequently used to predict the ecological risk of contaminated sediments in the field. This study investigates the bioassay conditions most relevant to achieving environmentally relevant field exposures. An identical series of metal-contaminated marine sediments were deployed in the field and laboratory over 31 days. Changes in metal concentrations and partitioning in both sediments and waters were used to interpret differences in metal exposure and bioaccumulation to the benthic bivalve Tellina deltoidalis. Loss of resuspended sediments and deposition of suspended particulate matter from the overlying water resulted in the concentrations of Cu, Pb and Zn (major contaminants) becoming lower in the 1-cm surface layer of field-deployed sediments. Lower exchange rates of overlying waters in the laboratory resulted in higher dissolved metal exposures. The prediction of metal bioaccumulation by the bivalves in field and laboratory was improved by considering the metal partitioning within the surface sediments. - Highlights: • Particulate metals are the dominant metal exposure route in laboratory and field tests (87). • There is an over-representation of the dissolved metal exposure in the laboratory (81). • Laboratory bioassays result in higher bioaccumulation of major metals, Cu, Pb, Zn (82). • Differences in exposure must be considered for a proper sediment quality evaluation (83). • Traditional measurements are not sufficient to explain bioaccumulation results (79). - To improve the value of field- and laboratory-based sediment bioassays in ecological risk assessments, it is necessary to create exposure conditions that resemble those in the field

Protocole d'entente entre le gouvernement de l'Inde et le CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

22 févr. 2018 ... Ce protocole d'entente réaffirme un engagement commun envers les données probantes et l'innovation en Inde en vue de favoriser le progrès social et ... Des chercheurs appuyés par le CRDI parlent de leurs expériences au Comité sur les ONG lors du forum de la Commission de la condition de la femme.

Le médicament générique au Maroc: le point de vue du ...

African Journals Online (AJOL)

Introduction: Le médicament générique est souvent une origine de préjugés négatifs et de méfiance chez les professionnels de santé et les patients. Ceci pourrait être dû à plusieurs facteurs entre autre le manque des connaissances du patient sur ces médicaments. Le but de notre étude était d'évaluer l'information du ...

Le CRDI au Bhoutan

International Development Research Centre (IDRC) Digital Library (Canada)

Il en résulte des solutions locales, novatrices et durables, qui offrent des choix aux personnes qui en ont le plus besoin et font changer les choses. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9. Pour en savoir plus, consulter la page. Web du Bureau régional de ...

Le CRDI au Kenya

International Development Research Centre (IDRC) Digital Library (Canada)

afin d'y favoriser la croissance et le développement. Il en résulte des solutions novatrices et durables qui ont pour but d'améliorer les conditions de vie et les moyens de subsistance. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9. Pour en savoir plus, consulter.

Le genre comme rapport d’inégalité sociale dans le discours publicitaire

Directory of Open Access Journals (Sweden)

Jean-Claude Soulages

2016-12-01

Full Text Available Loin de se réduire à une simple transaction commerciale, une annonce publicitaire est un espace de croyances sur des identités, des rôles et des pratiques sociales. Au même titre que d’autres productions fictionnelles de la culture de masse, elle représente l’une des faces de ce miroir social alimenté par la circulation incessante d’attitudes et de croyances, affichant même s’il s’agit bien souvent pour cette dernière d’un positionnement ludique, un second monde peuplé par nos avatars. La publicité tout comme le fait la fiction télévisée définit l’horizon des possibles d’une communauté donnée. Ce qu’elles réalisent toutes deux c’est l’entrée de l’imaginaire dans le réel. Même si, à partir des années 70, s’opère un lent défigement des stéréotypes sexistes, le publicitaire ne se fera aucunement le porte-parole explicite d’une quelconque lutte féministe, il optera toujours pour une tactique ambivalente de double speak: des effets de décadrage mettant en exergue des situations délibérément décalées ou burlesques (Un homme qui change les couches de bébé! Un clown qui fait la lessive!, mais cristallisant des inégalités de rôles. En jouant tout à la fois sur le défigement et la réactivation des stéréotypes, c’est bien un rôle de passeur et de go between, qu’est assigné le publicitaire en se faisant l’arbitre ventriloque de ces conflits de légitimité et de construction identitaire qui agitent notre modernité.

Storicizzare le teorie psicocritiche

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Roberto Talamo

2015-07-01

Full Text Available Le teorie psicoanalitiche della letteratura, dopo una fase di alterne fortune, sono oggi praticate da una cerchia di adepti sempre più ristretta. Le nuove koinè critico-teoriche tendono infatti a relegare la dottrina freudiana all’interno di un sapere letterario (e non interpretativo o a sostituire ad essa strumenti ritenuti più efficaci nella descrizione della sfera del mentale in letteratura (neuroestetica e neuronarratologia. La proposta storiografica che qui si avanza non vuole prendere parte in questo dibattito pro o contro la psicocritica, ma vuole leggere le proposte di teoria psicoanalitica della letteratura alla luce di una riflessione sul concetto di ibridazione, concetto sul quale queste teorie hanno costruito il loro confronto con i paradigmi teorici di volta in volta egemoni.

Le discours des Comices : un discours modèle

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Anne Herschberg Pierrot

2009-10-01

Full Text Available Dans un discours officiel, publié par le Journal de Rouen du 22 juillet 1853, Flaubert trouve une phrase du discours des Comices qu’il avait écrite la veille. Cet article présente et reproduit les discours cités par le Journal de Rouen.In an official speech, published in the Journal de Rouen on July 22nd 1853, Flaubert found a sentence from the Agricultural association (« Comices agricoles » speeches that he had actually written himself the previous evening. This article presents and reprints the speeches quoted by the Journal de Rouen.

Marine Bacteria with antimicrobials capacity isolated from cultures of bivalve mollusks

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Fabiola Pellon

2014-06-01

Full Text Available Microorganisms have commonly been studied as producers of antibacterial substances; yet they are also considered producers of antifungic, antiviral, antiparasitic, citotoxics and inhibitory of other forms of cellular growth substances. This paper describes the isolation, inhibitory potential and phenotipic characterization of native bacterial strains associated to bivalve mollusks such as Argopecten purpuratus “concha de abanico” and Crassostrea gigas “ostra” in cultivation systems. From 345 marine strains collected, 20 strains were recovered that had the ability of inhibiting a wide spectrum of fish, mollusks and shellfish pathogenic bacteria; being the most sensitive pathogens Aeromonas sobria P-281, Aeromonas hydrophila ATCC 7966, Vibrio vulnificus ATCC 27562 and Vibrio parahaemolyticus ATCC 17803. The phenotipic characterization of this strains with inhibitory capacity allowed the identification of the following genera: Vibrio (40%, Aeromonas (15%, Flavobacterium (10%, Pseudomonas (5%, Moraxella (5%, Flexibacter (5%. A 20% could not be identified. The results suggest that the isolated bacteria could be used as probiotics agents for the biological control of pathogens from marine organisms of interest in mariculture.

Le Débat des semences

International Development Research Centre (IDRC) Digital Library (Canada)

Solutions pour les lois nationales régissant le contrôle des ressources génétiques et des ...... des pouvoirs) qui reconnaissent, dans une certaine mesure, les droits de gestion collectifs des ...... documentés, les performances physiques, etc.

Le rôle des chefs traditionnels au Ghana : un modèle inspirant ...

International Development Research Centre (IDRC) Digital Library (Canada)

8 févr. 2011 ... Ray est également coordonnateur international du Traditional Authority ... Marketing social : le chef traditionnel acquiert une certaine expertise et ... Nadine Robitaille est rédactrice à la Division des communications du CRDI .

pour le trimestre qui a pris fin le 31 décembre 2012

International Development Research Centre (IDRC) Digital Library (Canada)

acray

31 déc. 2012 ... -24,8 %. Contributions de bailleurs de fonds. Financement de la programmation en recherche pour le développement. 39 837. 11 122. 9 044. 11 376. -20,5 %. 29 081. 25 399. 25 400. 0,0 % ..... internationales d'information financière (normes IFRS) telles que publiées par le Conseil des normes comptables ...

Le CERN ouvre ses entrailles au public

CERN Multimedia

2004-01-01

"Le CERN se lance dans une grande opération de relations publiques pour son cinquantième anniversaire. Le centre de recherche organisera une journée portes ouvertes le 16 octobre. Quelque 50 sites pourrant être visités" (1/2 page)

Processes of physical change to the seabed and bivalve recruitment over a 10-year period following experimental hydraulic clam dredging on Banquereau, Scotian Shelf

Science.gov (United States)

Gilkinson, K.; King, E. L.; Li, M. Z.; Roddick, D.; Kenchington, E.; Han, G.

2015-01-01

A previous study on the effects of experimental hydraulic clam dredging on seabed habitat and commercial bivalve populations revealed a lack of recovery after a 3-year post-dredging period (1998-2001) on a deep (65-75 m) offshore sandy bank on the Scotian Shelf, Canada. Follow-up sidescan sonar surveys were carried out 5 and 10 years after dredging (2003, 2008) in order to identify long-term processes of seabed recovery. Grab sampling was carried out 10 years after dredging to identify post-dredging commercial bivalve recruitment. Changes in the seafloor, including dredge tracks, were documented with a series of 7 sidescan sonar surveys between 1998 and 2008. A sediment mobility model was constructed based on modeled tidal current and hindcast wave data over this time period to quantify natural seabed disturbance and interpret changes to the dredge tracks mapped by sidescan sonar surveys. The model indicated that tidal currents had minimal effect on sediment mobilization. The main driving force associated with re-working of surficial sediments as evidenced by deterioration of dredge tracks in sonograms was annual fall/winter storms. While the annual frequency of storms and associated wave heights was variable, the observations and sediment mobility calculations suggest that the most influential variable is the magnitude of individual large storms, specifically storms with a significant wave height of ∼11 m. These storms are capable of generating mobile sediment layers of 20-30 cm thickness, equivalent to the dredge blade cutting depth. It appears that, with minor exceptions, sediment properties have returned to pre-dredging conditions 10 years after dredging in this habitat. Based on known age-length relationships, the four commercial bivalve species showed very low recruitment at the experimental site over the 10-year post-dredging period. However, this is unlikely due to a dredging effect since a similar pattern was observed in non-dredged areas.

DICKINSARTELLA FAUNA FROM THE SAIWAN FORMATION (OMAN: A BIVALVE FAUNA TESTIFYING TO THE LATE SAKMARIAN (EARLY PERMIAN CLIMATIC AMELIORATION ALONG THE NORTH-EASTERN GONDWANAN FRINGE.

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CRISTIANO LARGHI

2005-11-01

Full Text Available The transitional faunas of the Permian Huqf succession of Oman make it one of the key-sections for the intercalibration of Early to Middle Permian biostratigraphical scales. The abundance of fossils improved the knowledge of some marine faunas which populated the North-Eastern Gondwanan fringe during times of climatic changes in the Permian. A Sterlitamakian (upper Sakmarian, Lower Permian bivalve fauna from the Saiwan Formation in the Huqf area, informally named "Dickinsartella Fauna", is described in the present paper. The specimens examined were collected from the "Pachycyrtella Bed" (Auctorum, the basal bed of the Formation in its type locality. The Dickinsartella Fauna can be identified for the presence of the new genus Dickinsartella, which dominates the bivalve thanatocoenosis with D. pistacina sp. n. (type species. The bivalve fauna from the Pachycyrtella Bed includes the new species Stutchburia sangallii and Promytilus  mazzolenii, and also Astartella obliqua Dickins, 1963, Nuculopsis cf. bangarraensis Dickins, 1963, ?Oriocrassatella sp., and indeterminable aviculopectinids. This fauna shows a low taxonomic diversity. Nevertheless, some species are represented by a high number of generally well-preserved specimens, i.e. some specimens of S. sangallii sp. n. and A. obliqua show part of the ligament.  The good preservation of the shells permitted the microstructural analysis of D. pistacina sp. n. and S. sangallii sp. n. The microstructure of S. sangallii sp. n. supports the close phylogenetical link between modiomorphids and crassatelloids recognized by some previous authors.The new genus Dickinsartella includes the more recent species belonging to the important Paleozoic Order Cyrtodontida Scarlato & Starobogatov, 1971. The discovery of Dickinsartella gen. n. and other taxa of the Pachycyrtella Bed, present also in the Sakmarian levels of the Carnarvon and Perth Basins in Western Australia,  indicates a wider distribution of the

Le front oriental de Lille

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Étienne Poncelet

2011-06-01

Full Text Available De la porte d’eau de la Basse Deûle jusqu’au fort Saint-Sauveur, le front oriental de Lille, fortifié à l’époque espagnole, glisse ses courtines dans les entrelacs du périphérique et des gares. L’enjeu urbain actuel consiste à s’appuyer sur ces murs historiques pour « passer malgré tout » à travers cet écheveau urbain et retisser les fils de la continuité des promenades au cœur de la ville. Moins connus que le front occidental de la reine des citadelles, ces anciens espaces militaires sont une chance pour l’urbanisme de demain dont les opérations en cours de la Porte de Gand et de la Basse Deûle témoignent déjà.The east wall, at Lille, fortified during the period of Spanish occupation, extends from the Porte d'Eau de la Basse-Deûle to the Saint-Sauveur fort. Its curtain walls emerge today in a landscape of ring roads and railway territories. The issue today is to profit from these historic walls in order to make some sense of the urban chaos and to reinstate some urban continuity in the city-centre walkways. Although they are not as well known as the western wall of this major fortified city, these former military properties are an exciting opportunity for tomorrow's town-planners, as the operations already underway at the Porte de Gand et de la Basse Deûle suggest.

Le CRDI en Jordanie

International Development Research Centre (IDRC) Digital Library (Canada)

... dans les pays en développement afin d'y favoriser la croissance et le développement. Il en résulte des solutions novatrices et durables qui ont pour but d'améliorer les conditions de vie et les moyens de subsistance. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9.

Le CRDI au Mali

International Development Research Centre (IDRC) Digital Library (Canada)

de ces technologies et tentent de déterminer si un régime de microcrédit pourrait encourager leur adoption. On cherche par cela à accroître la sécurité alimentaire de même que le rendement des cultures de dolique, de sorgho et de mil. □ Menaces pesant sur les moyens de subsistance. Financement octroyé pour le Mali :.

L'astronomie dans le monde

Science.gov (United States)

Manfroid, J.

2008-09-01

Fragmentation et astéroïdes binaires; Astéroïde géocroiseur triple; Rosetta sort de son hibernation; Messenger; Transit lunaire vu par Deep Impact; Titan; Phobos; Phoenix; Einstein avait raison; Le ballet des taches rouges; Le poids des lentilles;

Prends soin du métro. Le contrôle-soin, forme émergente des régulations et menaces souterraines

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Yves Jouffe

2015-05-01

Full Text Available Le métro de Santiago a subi une dégradation significative de ses conditions de transport du fait de son intégration au Transantiago, le réseau de bus urbains. L’opérateur du métro a donné beaucoup de visibilité à ses dispositifs de contrôle des nouvelles masses d’usagers : barrières optimisées, signalétique omniprésente, agents démultipliés, etc. L’étude du discours officiel de l’entreprise et surtout l’observation ethnographique de ces dispositifs révèlent que les modalités de contrôle ont elles-mêmes évoluées. En plus de la menace légale exercée contre les étrangers et de la régulation des flux par une discipline des corps, un contrôle-soin s’exerce sur une population à protéger : la population qui bénéficie du soin de l’opérateur lui est redevable d’un contre-soin. Le contrôle-soin constitue non seulement une modalité émergente de contrôle mais aussi la forme générale du contrôle dans le métro de Santiago.

Le harcèlement moral au travail

CERN Document Server

Hirigoyen, Marie-France

2017-01-01

Isoler, discréditer, déconsidérer le travail rendu, intimider, insulter... Les moyens sont nombreux, les conséquences dramatiques. En France, la reconnaissance du harcèlement moral et sa condamnation juridique sont venues changer le regard que portent les salariés sur certaines situations vécues et interpeller les entreprises quant à leurs méthodes de management. Que sait-on aujourd’hui sur le harcèlement au travail ? Quels en sont les effets sur les individus, leurs proches et la société ? Comment le punir ou le prévenir ? En décortiquant les mécanismes du harcèlement, ses origines et ses conséquences ainsi que les réponses qui y sont actuellement apportées en France comme à l’étranger, cet ouvrage fait le point sur un fléau de nos sociétés narcissiques.

Le LHC, un tunnel cosmique

CERN Multimedia

CERN. Geneva

2009-01-01

Et si la lumière au bout du tunnel du LHC était cosmique ? En d’autres termes, qu’est-ce que le LHC peut nous apporter dans la connaissance de l’Univers ? Car la montée en énergie des accélérateurs de particules nous permet de mieux appréhender l’univers primordial, chaud et dense. Mais dans quel sens dit-on que le LHC reproduit des conditions proches du Big bang ? Quelles informations nous apporte-t-il sur le contenu de l’Univers ? La matière noire est-elle détectable au LHC ? L’énergie noire ? Pourquoi l’antimatière accumulée au CERN est-elle si rare dans l’Univers ? Et si le CERN a bâti sa réputation sur l’exploration des forces faibles et fortes qui opèrent au sein des atomes et de leurs noyaux, est-ce que le LHC peut nous apporter des informations sur la force gravitationnelle qui gouverne l’évolution cosmique ? Depuis une trentaine d’années, notre compréhension de l’univers dans ses plus grandes dimensions et l’appréhension de son comportement aux plus peti...

Le plurilinguisme du perroquet

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Manuel Mühlbacher

2012-05-01

Full Text Available La figure du perroquet occupe une position ambiguë face à la question de la traduction. Il est capable d’imiter des paroles en toutes les langues, mais il n’est capable d’en comprendre aucune — il ne peut que répéter des sons, c’est-à-dire des signifiants. Le traducteur semble faire le contraire quand il passe d’une langue à une autre en tâchant de transmettre une signification semblable par d’autres signes. L’article vise à discuter le rôle du traducteur et sa relation, éventuellement équivoque, au perroquet, en analysant la traduction allemande de Trois Contes par André Stoll et Cora van Kleffens. Un décalage au niveau sémantique peut éclairer l’interprétation du texte, par exemple en explicitant des allusions sous-jacentes, tandis que le transfert de la syntaxe française en allemand pose souvent des problèmes considérables. Comment le traducteur peut-il reproduire des structures syntaxiques qui n’existent pas en allemand, mais qui ne cessent de revenir dans le texte français ? Que faire si le texte se met à jouer au perroquet et finit par se singer lui-même ? André Stoll et Cora van Kleffens ont su trouver des stratégies pour affronter ces difficultés.The figure of the parrot holds an ambiguous position towards the question of translation. It is able to imitate all languages, but it will never understand any of them – its only skill is to mimic sounds, i.e. mere signifiers. On the contrary, the translator seems to be the antithesis of the parrot when he moves from one language to another. He endeavours to convey a similar meaning, but by different signs. The article aims at discussing the role of the translator and his or her eventually equivocal relation to the parrot by means of analysing the German translation of Trois Contes by André Stoll and Cora van Kleffens. Whereas a semantic divergence can result in a different tendency on the level of interpretation, as in the case of an underlying

Évaluation spatiale et prospectives sur le risque de pollution diffuse par le nitrate sur le bassin versant de la Bultière

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LE FLAHEC, François

2015-06-01

Full Text Available En France, la protection des captages d'eau potable est une préoccupation majeure : le Grenelle Environnement a identifié plus de cinq cents sites menacés par les pollutions diffuses, d'où la nécessité de mettre en place des plans d'action pour les protéger. En Vendée, dans le bassin versant de la Bultière, confronté à des rejets importants de nitrate, une étude par modélisation agronomique et hydrologique a été mise en œuvre avec le logiciel Swat, un outil alliant analyse spatiale et simulation, qui doit permettre de donner des orientations et de prioriser des solutions.

Le point sur les données ouvertes : réflexion sur leur rôle en ...

International Development Research Centre (IDRC) Digital Library (Canada)

L'ouverture de portails gouvernementaux de données ouvertes aux États-Unis et au Royaume-Uni en 2009 a été le fer de lance d'un mouvement mondial qui, près de dix ans plus tard, a été adopté par des dirigeants du monde entier, comme le montrent les objectifs de développement durable, l'accord de Paris sur le ...

Le massacre de la mariée

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Bastiaan van der Velden

2016-06-01

Full Text Available Le Massacre des innocents a été pour Marcel Duchamp l’une de ses sources en composant Le Grand Verre. Ce ‘massacre’ est dans ce cas plus précisément une attraction foraine. D’autre part l’infanticide à Bethlehem constitue un sujet maintes fois représenté par différents peintres. Pour Alfred Jarry, auteur littéraire et de théâtre qui a plus particulièrement inspiré Duchamp, le tableau Le Massacre des innocents de Breughel l’Ancien était une pièce clé qui lui permettait de démontrer pourquoi il rejetait l’art historisant en peinture et dans le théâtre.

Vers une plus grande collaboration régionale — le CRDI appuie le ...

International Development Research Centre (IDRC) Digital Library (Canada)

26 janv. 2011 ... Richard Fuchs croit que les gens qui veulent comprendre comment le monde évolue devraient jeter un coup d'oeil à la vague de transformations qui déferle sur ... Bien qu'ils aient souvent de la difficulté à se démarquer face à la véritable dynamo économique qu'est la Chine, des pays tels que le Laos, ...

Peut-on voyager dans le temps ?

CERN Multimedia

CERN. Geneva

2008-01-01

La possibilité de voyager dans le temps est régulièrement évoquée par les magazines scientifiques (et parfois même par les scientifiques). Elle est également le sujet de nombreux romans de science-fiction. Nous discuterons d’abord du sens qu’on peut donner à l’expression « voyager dans le temps », puis nous expliciterons ce que la physique contemporaine dit à ce propos.

Le CRDI à la COP23 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

En collaboration avec ses bénéficiaires et partenaires, le CRDI anime et participe à une série d'activités et d'événements durant la COP23, y compris des événements parallèles officiels de la CCNUCC et des groupes d'experts, des groupes de discussion, des ateliers et la 15e édition des Journées sur le développement et ...

Le rôle du récit de vie dans le discours politique de Lula The role of Lula’s Life Story in his Political Speeches

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Ida Lucia Machado

2011-10-01

Full Text Available Cet article propose une réflexion sur le rôle du récit de vie dans les discours politiques, et plus précisément dans les discours d’investiture à la présidence du Brésil de Luis Ignacio Lula da Silva. Il analyse quelques fragments qui mêlent expressément des souvenirs de sa vie passée aux discours politiques d’actualité, mais aussi qui font allusion à sa vie de façon indirecte. Dans le premier discours, Lula se présente comme un personnage de l’histoire, un « il » qui veut travailler pour la collectivité ; néanmoins, les allusions à sa trajectoire de vie le légitiment comme celui qui peut promouvoir le changement requis par le peuple. Dans le second discours, Lula utilise depuis le début un « je » ancré dans sa propre histoire : sa « petite » histoire personnelle semble ainsi s’incorporer à la « grande » histoire d’une nation. En ce sens, le récit de vie comprend une dimension argumentative qui permet de construire un ethos présidentiel par le jeu qu’il instaure entre l’individuel et le collectif, créant ainsi un effet de pathos qui appelle à l’identification. On s’interroge dans ce cadre sur la question du populisme dans son rapport aux stratégies de captation propres au discours politique.This paper analyzes fragments of President Luiz Inácio Lula da Silva’s inaugural speeches. Lula da Silva served as the President of Brazil for two consecutive terms in office. In his first inaugural speech, Lula da Silva refers to himself as a historical character, and uses the pronoun “he” (or “not-I”, a “he” at the service of the community. However, his path in life, mentioned in a single paragraph, legitimizes him as someone who is able to bring forward the changes demanded by the people. From the beginning of his second inaugural speech, Lula da Silva uses the pronoun “I”, which points to his own story: therefore, his “small, personal story” seems to be embedded into the

Le CRDI en Afghanistan

International Development Research Centre (IDRC) Digital Library (Canada)

Depuis près de 40 ans, le CRDI collabore étroitement avec les chercheurs des pays en développement et les appuie dans leur quête de moyens de créer des sociétés en meilleure santé, plus équitables et plus prospères. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G ...

Equazioni: le icone del sapere

NARCIS (Netherlands)

Bais, S.

2009-01-01

Il mistero del cosmo è scritto nel linguaggio della matematica, e le equazioni sono le frasi che ne esprimono la bellezza e la profondità. Cercare di spiegare la scienza senza equazioni è come cercare di spiegare l’arte senza illustrazioni: partendo da questo presupposto, Sander Bais presenta una

La culture matérielle enfantine entre le cute et le cool

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Gilles Brougère

2012-11-01

Full Text Available Cet article explore la façon dont on adresse un objet à l’enfant, c’est-à-dire la rhétorique à l’œuvre pour séduire les enfants (et les parents dans certains cas. Si l’éducation peut être présente pour certains produits, domine très largement aujourd’hui une rhétorique du fun, une association de l’objet à l’enfance via le divertissement et l’insertion dans une culture des pairs. Pour partie cet adressage se fait à travers l’utilisation de personnages ou d’univers sous licence qui proposent une rhétorique du fun prête à l’emploi. Mais l’analyse des univers disponibles montre que l’on peut décomposer le fun à travers deux pôles opposés, le cute, dont Hello Kitty constitue un exemple archétypal, et le cool, que Titeuf permet de saisir dans sa logique. A travers la distinction du cute et du cool, il s’agit de contribuer à l’analyse du déploiement contemporain d’une culture du divertissement qui est incorporée aux objets de l’enfance, tout en étant un moyen de capter l’intérêt de ceux-ci.

On Leśniewski’s Characteristica Universalis

NARCIS (Netherlands)

Betti, A.

2010-01-01

Leśniewski's systems deviate greatly from standard logic in some basic features. The deviant aspects are rather well known, and often cited among the reasons why Leśniewski's work enjoys little recognition. This paper is an attempt to explain why those aspects should be there at all. Leśniewski

Ultrasound assisted enzymatic hydrolysis for isolating titanium dioxide nanoparticles from bivalve mollusk before sp-ICP-MS.

Science.gov (United States)

Taboada-López, María Vanesa; Iglesias-López, Sara; Herbello-Hermelo, Paloma; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

2018-08-14

Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100 μs has been tested for assessing titanium dioxide nanoparticles (TiO 2 NPs) in bivalve mollusks. TiO 2 NPs isolation from fresh mollusk tissues was achieved by ultrasound assisted enzymatic hydrolysis procedure using a pancreatin/lipase mixture. Optimum extraction conditions imply ultrasonication (60% amplitude) for 10 min, and 7.5 mL of a solution containing 3.0 g L -1 of pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO 2 NPs concentration of 5.33 × 10 7  ± 8.89 × 10 6 , n = 11), showing a limit of detection of 5.28 × 10 6 NPs g -1 , and a limit of detection in size of 24.4-30.4 nm, based on the 3σ criteria, and on the 3σ/5 σ criteria, respectively. The analytical recovery within the 90-99% range (use of TiO 2 NPs standards of 50 nm at 7 and 14 μg L -1 as Ti). Several bivalve mollusks (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analyzed for total titanium (ICP-MS after microwave assisted acid digestion), and for TiO 2 NPs by the proposed method. TiO 2 NPs concentrations were within the 2.36 × 10 7 -1.25 × 10 8 NPs g -1 range, and the most frequent sizes were from 50 to 70 nm. Copyright © 2018 Elsevier B.V. All rights reserved.

Le déficit de filles

International Development Research Centre (IDRC) Digital Library (Canada)

de la population est une tendance plus récente. C. Le déficit de filles. Le déséquilibre du ratio hommes-femmes en Inde. D. R. O. I. T. S. D. E. S. F. E. M. M. E. S. E. T. P. A. R. T. IC. I. P. A. T. IO. N. C. I. T. O. Y. E. N. N. E. CENTRE DE. RECHERCHES. POUR LE. DÉVELOPPEMENT. INTERNATIONAL. CRDI : Jason Taylor ...

Le vide univers du tout et du rien

CERN Document Server

Diner, Simon

1997-01-01

Pourquoi l'Univers plutôt que le vide ? Le temps et l'espace existent-ils en l'absence de l'Univers ? Que reste-t-il quand tout est enlevé ? Pourquoi quelque chose plutôt que rien ? Depuis des siècles, ces interrogations mobilisent philosophes et physiciens. Mais aujourd'hui, le vide n'est pas le rien. Il serait même l'acteur central de l'histoire de la matière et de l'Univers, le partenaire privilégié de la physique. Vide et matière ne sont plus deux manifestations séparées de la nature, mais deux aspects d'une même réalité. Le vide est l'état de base dont la matière émerge, sans couper son cordon ombilical Le vide comme Univers du rien cède la place au vide comme Univers du tout. Que le vide puisse être conçu par les physiciens comme réservoir potentiel d'univers, voici qui ne devrait laisser personne indifférent. Ce livre ouvre un débat et nous convie à une réflexion surprenante.

Le charme slave

Directory of Open Access Journals (Sweden)

Antonella Mauri

2012-09-01

Full Text Available Antonella Mauri analyse l’image des femmes slaves immigrées en Italie telle qu’elle apparaît à travers la publicité, la littérature romanesque (La ballata dei lavavetri de Peter Del monte, Luce Profuga de Valerio Aiolli, Pornokiller de Bruno Ventavoli, le cinéma, la bande dessinée (Danilo Maramotti, image qu’elle oppose aux résultats d’une enquête qu’elle a menée sur le terrain. Elle s’interroge en particulier sur la permanence des stéréotypes liés à la femme slave.

Le matérialisme scientifique

Science.gov (United States)

Meunier, Jean-François

2004-03-01

De nos jours, il arrive quotidiennement aux grands hommes d'avoir à fréquenter d'ignorants mortels épris d'une conviction maladive que la science est la grande responsable de tous les maux du monde. Évidemment sans physique atomique, il n'y aurait pas eu d'Hiroshima et sans révolution industrielle, pas de pollution et etc. Cependant, ces accusations envers le progrès technique sont tout à fait injustes, irréfléchies et, j'irai même jusqu'à dire, irresponsables, puisque le calcul, i.e. la planification, même la plus élémentaire, est ce qui caractérise le mieux, pragmatiquement, la société humaine. À mon avis, les problèmes sociaux tireraient plutôt leur origine de sciences sociales irréalistes, qui, concrètment, inspireraient ou serviraient d'alibis à ceux qui détiennent véritablement le pouvoir. Dans cet article, je tenterai donc de démontrer la meilleure véracité et efficacité du matérialisme scientifique. Cette doctrine, dont Mario Bunge est le plus illustre représentant, s'appuy sur les résultats théoriques et expérimentaux des sciences factuelles ainsi que sur l'exactitude logique des mathématiques, utilisées ici comme langage universel de l'expression des idées. Cette conception philosophique qui s'inspire principalement du modèle des théories physiques, stipule que les réalités sociales sont, comme tout autre réalité, matérielles, mathématisables et représentables comme des systèmes en interaction. En fait, le modèle des physiciens ayant historiquement fait ses preuves en matière de testabilité et de cohérence interne est proposé d'être appliquer aux sciences sociales, aujourd'hui scindées des sciences dites pures sous l'inspiration des pseudo penseurs néo-kantiens, phénoménologiques et post-moderne. Cette nouvelle approche permettrait ainsi d'évoluer plus exactement vers une compréhension des bases sociales et biologiques du comportement humain afin de développer une éthique sans cesse plus r

Le Corbusier’s Dioramas

Directory of Open Access Journals (Sweden)

José Ramón Alonso Pereira

2013-10-01

Full Text Available AbstractLe Corbusier symbolizes the modern rational urbanism, whose rigorous effort of town planning demands a parallel effort of comprehension. It opposes to these contemporary urbanism that wish to perceive and to enjoy cities in a sensible way. Nevertheless, sentiment and reason are not adverses and Le Corbusier gives us at his  moment keys to intent a synthesis, joined them in a singular way by means of his ‘boîtes à miracles’ or ‘magic boxes’: those "architectural spectacles of synthesis" that he defined in 1951 Ciam. Here we try to approach to the first of those ‘spectacles’: the ‘diorama’, considering it as a corbusean strategy of mediation between rational and sensible in modern and contemporary city.Key wordsLe Corbusier, diorama, Ville Contemporaine, Plan Voisin, Plan Maciá

Conception d’un automate cellulaire non stationnaire à base de graphe pour modéliser la structure spatiale urbaine: le modèle Remus

Directory of Open Access Journals (Sweden)

Arnaud Banos

2007-10-01

Full Text Available Nous proposons dans cet article une formalisation originale des automates cellulaires géographiques, à même de mieux prendre en compte grâce à une structure de graphe le voisinage irrégulier et dynamique d’entités spatiales. Le modèle Remus permet ainsi de représenter sous la forme d’un graphe mathématique les entités spatiales du bâti et les réseaux de transport urbain (graphe urbain ; il permet aussi de calculer la distance-temps entre bâtiments par le réseau. Le modèle Remus permet l’extraction de différents graphes, dont le graphe fonctionnel des distances-temps entre les immeubles et le graphe de relations de voisinage qui représente le voisinage par le réseau pour un certain seuil de temps de trajet et pour un mode de transport donné.

Faire la chose « la plus sensée » pour le Canada et pour le monde ...

International Development Research Centre (IDRC) Digital Library (Canada)

18 déc. 2014 ... Je faisais partie de la délégation qui a accompagné dernièrement le gouverneur général du Canada, Son Excellence le très honorable David Johnston, et Son Excellence Sharon Johnston au ... Il avait ensuite a déclaré que ce que le CRDI a fait au Chili, c'est qu'il a permis aux idées de continuer de vivre.

[FR] Le developpment du Travail Social et le pluralisme au Québec

Directory of Open Access Journals (Sweden)

André Jacob

2011-06-01

Full Text Available Normal 0 21 false false false ES X-NONE X-NONE MicrosoftInternetExplorer4 Au Canada et au Québec, traiter des questions liées à la diversité culturelle et au racisme a été un défi pour les gouvernements depuis les années soixante. Auparavant et jusqu'à présent, une grande partie des responsabilités en termes de développement ethnoculturel sensible des services publics (services sociaux, des programmes de formation en travail social, etc. ont été laissés aux mains d’organismes de charité non-lucratifs. Cependant, peu à peu, depuis les années soixante, le gouvernement fédéral et le gouvernement provincial, ont dû développer des politiques et des programmes d'action. Au Québec, le travail social a fait partie du débat face à deux grands courants politiques, l’un canadien basé sur le multiculturalisme, et l’autre québécois basé sur l'interculturalisme. L'article vise à donner une perspective historique

L'espace, un outil de contrôle ? : Le cas Pont-à-Mousson (1921-190

OpenAIRE

Labardin, Pierre

2011-01-01

Cet article s'intéresse aux impacts des open space en matière de contrôle à partir d'un travail historique. Nous nous demandons si l'espace de travail peut constituer un outil de contrôle opérationnel. Dans une première partie, nous proposons une définition historique des espaces travail qui nous amène à justifier notre méthodologie de recherche historique. Nous travaillons à partir des archives des années 1920 de la société Pont-à- Mousson. Nous présentons longuement le contexte de la mise e...

Révolution tunisienne et Internet : le rôle des médias sociaux

OpenAIRE

Lecomte, Romain

2013-01-01

Suite au mouvement de contestation populaire qui a conduit à la chute du régime de Ben Ali, médias et experts des NTIC ont beaucoup insisté sur le rôle révolutionnaire joué par Internet en Tunisie, et plus particulièrement par les « réseaux sociaux ». Dans cet article, tout en cherchant à analyser comment, concrètement, les usages d’Internet ont pu servir de catalyseur au mouvement de contestation né à Sidi Bouzid, nous mettons en garde contre certaines analyses en vogue véhiculant le mythe d...

Le déficit de filles — Le déséquilibre du ratio hommes-femmes en Inde

International Development Research Centre (IDRC) Digital Library (Canada)

Plusieurs acteurs, dont le journal national indien The Hindu, ont qualifié ce brusque ... Voilà pourquoi le Centre de recherches pour le développement international ... De nouvelles tendances, comme la limite de deux enfants par famille, .... les professionnels de la santé et d'abolir les initiatives favorisant la stérilisation.

Droits d'auteur | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Droits d'auteur détenus par le CRDI Sauf indication contraire, les droits d'auteur relatifs aux documents mis en ligne sur le présent site Web sont détenus par le Centre de recherches pour le développement international (CRDI).

Rhythmic patterns in ancient shells: Can we reconstruct sub-annual cyclicity in trace element and stable isotope profiles from rudist bivalves?

Science.gov (United States)

de Winter, N.; Sinnesael, M.; Vansteenberge, S.; Goderis, S.; Snoeck, C.; Van Malderen, S. J. M.; Vanhaecke, F. F.; Claeys, P.

2017-12-01

Well-preserved shells of Torreites rudists from the Late Campanian Saiwan Formation in Oman exhibit fine internal layering. These fine (±20 µm) laminae are rhythmically bundled (±400 µm) and subdivide the shells' larger scale annual lamination (±15 mm), suggesting the presence of several interfering cycles in shell growth rate. The aim of the present study is to determine the duration and chemical signature of these rhythmic variations in shell composition. To achieve this, a range of micro-analytical techniques is applied on cross sections through the shells. Firstly, microscopy-based layer counting and colorimetric analysis are carried out on thin sections of shell calcite. Secondly, X-Ray Fluorescence (XRF) and Fourier Transform InfraRed (FTIR) mapping of cross sections of the shells reveal chemical and structural differences between laminae in 2D. Thirdly, high-resolution XRF (25 µm) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS; 10 µm) trace element profiles are used to quantify variations in chemical composition between shell laminae. Fourthly, annual chronology is established based on micro-sampled stable carbon and oxygen stable isotope measurements (250 µm) along the growth axis of the shells. Finally, spectral analysis routines are applied to extract rhythmic patterns matched to the shell laminae from the structural, chemical and colorimetric data. Combining these methods allows for a full evaluation of the structural and chemical characteristics as well as the timing of sub-annual lamination in rudist shells. The results of this study shed light on the external factors that influenced growth rates in rudist bivalves. A better understanding of the timing of deposition of these laminae allows them to be used to improve age models of geochemical records in rudist shells. Characterization of small scale variations in shell composition will characterize the uncertainties contained within lower resolution proxy records from

Le Combat de l’amour divin et de l’amour profane : un ballet de Charpentier pour le collège d’Harcourt

OpenAIRE

Demeilliez , Marie

2014-01-01

International audience; De l’activité de Marc-Antoine Charpentier au service des jésuites, nous sont parvenus un vaste répertoire religieux ainsi que le célèbre « opéra chrétien » David et Jonathas (1688), l’une des rares partitions composées pour le collège Louis-le-Grand qui soit conservée. Alors que le musicien en fut le maître de musique pendant plusieurs années, l’on sait peu de choses de sa participation aux somptueuses représentations théâtrales dont le collège s’est fait une spécialit...

La preuve par le nombre

Directory of Open Access Journals (Sweden)

Hélène Verdier

2012-04-01

Full Text Available S’il en était besoin, la question des usages et de la finalité des résultats de l’inventaire général pourrait être abordée par le nombre : nombre d’œuvres répertoriées, de communes inventoriées, de clichés photographiques réalisés, de dossiers, de consultations des notices dans les bases de données… Les additions aujourd’hui sont éloquentes, mais elles laissent dans l’ombre le rôle de l’inventaire qui, en mettant en œuvre une démarche systématique de connaissance, participe à l’ identificatio...

Le bord de la solitude

Directory of Open Access Journals (Sweden)

Jean-Paul Galibert

2010-04-01

Full Text Available La solitude a un bord, et non un seuil, parce que sinon, ce ne serait pas la solitude. Car le seuil a ceci de merveilleux qu’il sépare un dedans et un dehors, en sorte qu’il reste franchissable, et que l’on peut toujours sortir, et rentrer à sa guise. De ce fait, où que soient les autres, le seuil garantit donc que je pourrais les rejoindre, et me délasser, en changeant de lieu, des inconvénients croisés de l’intérieur et de l’extérieur. Dans le seuil, la métaphore implicite de la maison nous...

Leïomyosarcome de la prostate: Neoplasie rare

Directory of Open Access Journals (Sweden)

D. Basraoui

2012-03-01

La TDM et surtout l'IRM jouent un rôle primordial dans le bilan d'extension locale et à distance du léïomyosarcome prostatique et le seul moyen pour affirmer le diagnostic est l'histologie complétée par une étude immuno-histochimique. Leur prise en charge thérapeutique n'est pas codifiée à l'heure actuelle et leur pronostic reste très sombre.

Le mur intrapsychique chez le sujet métissé

Directory of Open Access Journals (Sweden)

Sonia Gérard

2010-06-01

Full Text Available Dans le contexte d’un couple culturellement mixte, la formation du couple implique un traitement des frontières interculturelles. De même que la naissance des enfants induisant une possible activation du processus du métissage, agit sur ces murs interculturels. Ainsi le paradigme du mur a une réelle fonction heuristique en ce qu’il permet de modéliser divers phénomènes psychiques par la constitution de représentations faisant intervenir la vision et le toucher. Nous nous sommes appuyés sur les fonctions du mur de Berlin pour comprendre notamment les phénomènes de clivage et sa résolution.In the field of mixed couples, the very formation of the couple implies intercultural borders. The birth of children, which activates the “mixing” process, may have a possible effect on these borders which are often represented as walls. Therefore the wall paradigm has a very heuristic function insofar as it allows the modelization of psychical phenomenon through representations using vision and touch. This paper considers various functions of the Berlin wall in order to understand processes such as cleaving and its resolution.

Nouvelles espèces d’Orchomene s.l. (Crustacea-Amphipoda) des fonds abyssaux. Affinités avec les autres Orchomene profonds

NARCIS (Netherlands)

Bellan-Santini, D.

1990-01-01

Deux espèces d’ Orchomene aveugles appartenant aux communautés benthiques abyssales sont décrites. O. kaikoi a été récolté dans le grand bivalve Calyptogena (Ectenagena) phaseoliformis provenant des fosses de subduction du Japon. O. stocki provient du lavage d’épongés du genre Cladorhiza récoltées

Le rapport Coopération pour le développement de l'OCDE souligne ...

International Development Research Centre (IDRC) Digital Library (Canada)

14 févr. 2018 ... Cette 55e édition du rapport Coopération pour le développement fournit une analyse exhaustive des contraintes liées aux données auxquelles les pays en développement sont confrontés de nos jours, ainsi que des options stratégiques visant à compiler de meilleures statistiques pour le développement ...

Quel contrôle de gestion pour les startups ?

OpenAIRE

Meyssonnier , François

2015-01-01

Une étude de huit PME fondées sur la science permet d’identifier les spécificités du contrôle de gestion des startups. Dans les startups émergentes le dirigeant n’utilise que des linéaments de contrôle de gestion essentiellement pour développer son approche cognitive du business model. Dans les startups en croissance le contrôle de gestion a un rôle de garde-fou et les outils de pilotage de la performance sont utilisés essentiellement de façon interactive et pour la prévision. Les principaux ...

Les enjeux du modèle standard

CERN Document Server

CERN. Geneva

2008-01-01

Toute la matière visible dans l'Univers est décrite par le « Modèle Standard ». Selon cette théorie, la matière est constituée d'atomes, qui contiennent des électrons orbitant autour de noyaux, dont les composants fondamentaux sont les quarks. Quatre forces fondamentales agissent entre ces particules élémentaires : les forces électromagnétique est gravitationnelle, et les interactions nucléaires forte et faible. La description fournie par le Modèle Standard de ces particules et de leurs interactions est en parfait accord avec les expériences. Néanmoins, des questions fondamentales restent sans réponse jusqu'à maintenant : d'où vient la masse des particules ? Pourquoi y a-t-il tant de types de particules ? Existe-t-il une théorie unifiée de toutes les interactions ? Quelle est la nature de la matière cachée prédite par les astrophysiciens ? Le LHC au CERN donnera des éléments de réponse à ces questions au-delà du Modèle Standard.

Le patrimoine astronomique provençal

Science.gov (United States)

Rous, M.; Figon, P.; Guyot, S.

2012-12-01

L'OSU OAMP/Institut Pythéas porte les missions de conservation, inventaire et valorisation du patrimoine. Suite à la fusion de l'Observatoire de Marseille et du Laboratoire d'Astronomie Spatiale en 2000 pour créer le Laboratoire d'Astrophysique de Marseille, le déménagement des équipes sur le site de Château-Gombert en 2008 a soulevé le problème du devenir des collections des deux sites d'origine. Nous ferons le bilan des actions passées en matière de conservation et de valorisation de ce riche patrimoine : versement à l'inventaire général du Ministère de la Culture, classement de 22 instruments au titre des Monuments Historiques, inventaire et numérisation des archives anciennes, montage d'expositions et réalisation du catalogue Telescopium, 400 ans de lunettes et de télescopes. Nous présenterons les actions en cours: mesures de conservation préventive, inventaire des archives et des instruments. Nous parlerons enfin des projets: création d'un espace d'exposition permanente, participation à des expositions temporaires.

Publications | Page 17 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Publication du rapport de BSR sur le travail des enfants en Birmanie. Le CRDI finance plusieurs projets de recherche sur les facteurs expliquant le travail des enfants, incluant le rapport intitulé 'Child labor in Myanmar's Garment Sector' écrit récemment par l'organisme Business for Social Responsibility (BSR).

Savoir gérer le mal

Directory of Open Access Journals (Sweden)

Michel Maffesoli

2015-09-01

Full Text Available Le sens commun, conservatoire immémorial de la sagesse humaine « sait », de savoir incorporé, que le mal, l’ombre, la mort, la douleur sont des caractéristiques essentielles de l’existence en son entièreté. Dès lors les créatures quelles qu’elles soient, sont des manifestations de la vie et, dès lors, méritent une attitude « compassionnelle », fraternelle, parce qu’ensemble elles constituent le flux vital. C’est ainsi que l’on peut comprendre l’utilité sociale de ces divers « mondes intermédiaires » que sont les croyances, religieuses ou philosophiques, au « double », au « daimon », aux esprits et autres figures tutélaires ou effrayantes. Elles aident à vivre, au jour le jour, la souffrance en la communalisant.

L'analyse des risques l'expert, le décideur et le citoyen

CERN Document Server

Chevassus-au-Louis, Bernard

2007-01-01

Selon le modèle "standard" d'analyse du risque, utilisé majoritairement aujourd'hui, les experts basent leurs pratiques sur des hypothèses, des concepts, voire des valeurs implicites qui ne peuvent être considérées comme des évidences. La fin du XXe siècle a marqué une crise de l'expertise. Progressivement s'est instauré un débat autour du principe de précaution, principe dont l'application a des conséquences pour la décision et pour l'évaluation du risque lui-même. De son côté, la société civile a un rôle participatif fort à jouer. Se dessinent ainsi les contours d'une analyse de risque "postmoderne", dite "constructiviste", qu'il s'agit de mettre à l'épreuve concrètement.

Le Parti paysan d’union sociale

OpenAIRE

Bensoussan, David

2015-01-01

La fondation, le 11 juillet 1945 à Paris, du Parti paysan n’a sans doute guère suscité l’attention des contemporains alors immergés dans le contexte tumultueux de l’immédiat après-guerre. Il faut d’ailleurs attendre la parution, quelque temps plus tard, le 6 octobre, du premier numéro de L’Unité Paysanne, organe hebdomadaire de cette nouvelle formation politique, pour que sa naissance soit publiquement officialisée. Sans vouloir surévaluer l’importance d’une organisation qui n’arrivera jamais...

Le primitif et le mystique chez Lévy-Bruhl, Bergson et Bataille.

Directory of Open Access Journals (Sweden)

Frédéric Keck

2004-04-01

Full Text Available L’assimilation du fou, du primitif et de l’enfant a été souvent analysée comme une opposition de l’archaïque par rapport au civilisé ou du normal par rapport au pathologique. On veut montrer ici que le mystique s’ajoute à cette liste, celle-ci désignant alors plutôt des figures de l’altérité qui défient la raison. On étudie alors les liens entre la figure du primitif et celle du mystique dans la sociologie de Lévy-Bruhl, la métaphysique de Bergson et la pratique littéraire de Bataille. Par-delà les divergences entre ces trois œuvres, on montre que le lien entre primitif et mystique vise à élargir le champ de l’expérience en l’ouvrant à une altérité radicale, et en même temps prépare le terrain pour cette expérience vide et formelle que pensera le structuralisme.French human sciences at the beginning of the 20th century used to assimilate the figures of the mad person, the primitive and the child. The Author shows that this assimilation should not be interpreted in the sense of an opposition between the archaic and the developed, or the normal and the pathological, but, once the figure of the mystic is added to this list, in the sense of an opposition between rationality and its other. Three examples allows to analyse the link between the figures of the primitive and the mystic : the sociology of Lévy-Bruhl, the metaphysics of Bergson, the literature of Bataille. Through the reading of these three works, the Author shows that the link between the figures of the primitive and the mystic allows to think a larger experience by opening it to an alterity, and at the same time prepares the ground for an empty and formal experience that will be explored by structuralism.

Effet du stress salin sur le comportement physiologique et ...

African Journals Online (AJOL)

SARAH

30 juin 2013 ... rapidement dans les feuilles à partir de 25 mmol de NaCl. Le rapport de sélectivité K+/Na+ a été plus discriminant entre les variétés : Midass a présenté le rapport de sélectivité le plus élevé et Nabeul le rapport de sélectivité le plus faible. Conclusion et application : La variété Nabeul qui est de type piment ...

Le Recul de la Forêt au Viet Nam

International Development Research Centre (IDRC) Digital Library (Canada)

Le fait d'ignorer la réalité pragmatique dans un souci d'opportunisme politique ne ... Si le texte de l'étude que voici a été rédigé en solo, les choses ont été fort différentes sur ..... Parmi les ressources requises par le système mondial — mis en place par les .... Les guerres dont le Viet Nam a été le théâtre au cours du dernier ...

Le rôle des universités africaines dans l'innovation au service du ...

International Development Research Centre (IDRC) Digital Library (Canada)

Un nouveau réseau de recherche s'intéressera aux façons dont les universités africaines peuvent contribuer à stimuler l'innovation sur le continent noir. Le projet de recherche permettra d'examiner dans quelle mesure les universités favorisent les innovations qui contribuent à l'insertion économique des populations ...

Characterization of freshwater bivalves as radio contamination (57Co, 110mAg, 134Cs) bio-indicators in a metallic multi pollution context (Cd, Zn)

International Nuclear Information System (INIS)

Fraysse, B.

2001-07-01

This study concerns freshwater bio-indicators of radio-contamination, in a metallic multi-pollution context. Metals, such as cadmium (Cd) and zinc (Zn), are widely represented in aquatic ecosystems, and their concentrations can induce physiological effects. This chronicle exposure generates both metabolic and behaviour stress of individuals, and can also yield to detoxification mechanisms induction. The main goal of this work was to estimate the influence of metals on the radionuclides ( 57 Co, 110m Ag, 134 Cs) bioaccumulation by two different bivalve species (Corbicula fluminea et Dreissena polymorpha), by studying the contamination level, the kinetic of the radionuclide transfer and the soft-body repartition. As the exploratory feature of this study, two parts have been developed: (i) testing the problematic suitability in a really bio-monitoring situation, and (ii) analysing the metal/radionuclide interaction mechanisms under controlled and standardised conditions (laboratory). For the different experimental conditions explored (laboratory and field), radionuclide bioaccumulation by freshwater bivalves has been influenced by metal exposure. This result was obtained after assessing a decrease of the organisms contamination level by radionuclide and their accumulation rate, an increase of their depuration rate and tissue and cellular repartition changes. (author)

Publications | Page 200 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le CRDI collabore avec les chercheurs et les établissements des pays en développement au renforcement des capacités locales par le truchement du financement, de la mise en commun des connaissances et de la ... Le partage de l''information et des techniques de la communication favorise le développement durable.

Publications | Page 103 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le FIE 2008 fait avancer le cadre écobiosocial de l'OMS. Le Programme spécial de recherche et de formation concernant les maladies tropicales (TDR) de l'OMS a élaboré le concept du champ « écobiosocial », qui combine les perspectives écologiques, biologiques et sociales « pour mieux.

Une approche écosanté pour le contrôle de la fièvre de la vallée du ...

International Development Research Centre (IDRC) Digital Library (Canada)

17 août 2016 ... Ces conclusions sont particulièrement pertinentes à la lumière des avancées récentes réalisées pour le vaccin contre la fièvre de la vallée du Rift et seront un important facteur à prendre en compte pour le moment de lancer le futur vaccin et la manière de le faire. Les tendances de mobilité du bétail ...

Le limus rédempteur de Andrej Tarkovski

Directory of Open Access Journals (Sweden)

Paolo Mottana

2015-04-01

Full Text Available Le cinéma de Tarkovski est riche de présences symboliques. L'essai rend, à travers le contact prolongé et fidèle aux différentes oeuvres du metteur en scène russe, la constellation de ses éléments archetipiques et de ses figures les plus significatives. Le dialogue terre-eau, le travail du feu, la récurrence de l'arbre, du bois, de l'enfance, le flux lent du temps, la phenomenologie poétique de la maison. Dans le cinéma de Tarkovski on se perd, son oeuvre, un vrai opus magnus alchimique, est un voyage dans la survivance d'un halètement mystique profondément incarné dans la matière terrestre. Son parcours circulaire, de l'arbre brûlé d'Ivan à ce qui renaît à la fin du Sacrifice miraculeusement, c'est une cheville fondamentale pour pouvoir expérimenter la puissance de l'imagination créatrice quand encore elle est l' expression d'une sensibilité inspirée à l'âme du monde".

Amélioration des moyens de subsistance agropastoraux dans le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le CRDI lance un nouveau projet dans la région de l'ANASE. L'honorable Chrystia Freeland, ministre du Commerce international, a annoncé le lancement d'un nouveau projet financé par le Centre de recherches pour le développement international (CRDI). Voir davantageLe CRDI lance un nouveau projet dans la région ...

Gestion du Centre | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le Comité de gestion du Centre (CGC) est composé des membres de la haute direction du CRDI, notamment les directeurs de nos quatre bureaux régionaux et de nos principaux secteurs de programme. Le CGC travaille en collaboration avec le président afin de soutenir la recherche pour le développement, lui fournissant ...

Le travesti dans le théâtre du xixe siècle : une distribution à contre-genre ?

OpenAIRE

Khoury, Camille

2018-01-01

Quelques-unes des actrices les plus célèbres du xixe siècle ont laissé à la postérité le souvenir de leurs rôles travestis. C’est notamment le cas de Virginie Déjazet – au point que le déjazet est rapidement devenu synonyme de rôle travesti – ou encore de Sarah Bernhardt. Le travesti est alors un spectacle commun sur les scènes académiques françaises – tandis que certains rôles sont écrits pour être joués en travesti, de grandes actrices s’emparent de rôles masculins pour confronter leur géni...

Ecological studies of wood-boring bivalves in the vicinity of the Oyster Creek Nuclear Generating Station. Progress report Sep-Nov 81

International Nuclear Information System (INIS)

Hoagland, K.E.; Crocket, L.

1982-06-01

The species composition, distribution, and population dynamics of wood-boring bivalves are being studied in the vicinity of the Oyster Creek Nuclear Generating Station, Barnegat Bay, New Jersey. Untreated wood test panels are used to collect organisms at 12 stations. Physiological tolerances of 3 species are also under investigation in the laboratory. Competition among the species is being analyzed. In the fall of 1981, Teredo bartschi remained in Oyster Creek despite continuous prolonged outages of the Oyster Creek Nuclear Generating Station

Manganese in the shell of the bivalve Mytilus edulis: Seawater Mn or physiological control?

Science.gov (United States)

Freitas, Pedro S.; Clarke, Leon J.; Kennedy, Hilary; Richardson, Christopher A.

2016-12-01

Manganese in the shell calcite of marine bivalves has been suggested to reflect ambient seawater Mn concentrations, thus providing a high-resolution archive of past seawater Mn concentrations. However, a quantitative relationship between seawater Mn and shell Mn/Ca ratios, as well as clear understanding of which process(es) control(s) shell Mn/Ca, are still lacking. Blue mussels, Mytilus edulis, were grown in a one-year duration field experiment in the Menai Strait, U.K., to study the relationship between seawater particulate and dissolved Mn2+ concentrations and shell calcite Mn/Ca ratios. Shell Mn/Ca showed a well-defined intra-annual double-peak, with maximum values during early spring and early summer and low values during autumn and winter. Seawater particulate Mn peaked during winter and autumn, with a series of smaller peaks during spring and summer, whereas dissolved Mn2+ exhibited a marked single maximum during late-spring to early-summer, being low during the remainder of the year. Consequently, neither seawater particulate Mn nor dissolved Mn2+ concentrations explain the intra-annual variation of shell Mn/Ca ratios. A physiological control on shell Mn/Ca ratios is evident from the strong similarity and timing of the double-peaked intra-annual variations of Mn/Ca and shell growth rate (SGR), the latter corresponding to periods of increased metabolic activity (as indicated by respiration rate). It is thus likely that in M. edulis SGR influences shell Mn/Ca by altering the concentration or activity of Mn2+ within the extra-pallial fluid (EPF), by changing the flux of Mn into or the proportion of protein bound Mn within the EPF. By linking shell Mn/Ca ratios to the endogenous and environmental factors that determine growth and metabolic activity, this study helps to explain the lack of a consistent relationship between shell Mn/Ca in marine bivalve shell calcite and seawater particulate and dissolved Mn2+ concentrations. The use of Mn content from M. edulis

Le Cercle de vie : l'agriculture biologique au Mexique | CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

13 juil. 2011 ... Le marché, Le Círculo de producción y consumo responsable [le Cercle ... En 2001, le Centre de recherches pour le développement international (CRDI) a financé ... provenant du calcaire utilisé dans l'ancien mode de transformation du ... Droits d'auteur · Éthique de la recherche · Politique de libre accès ...

J'ai le plaisir de vous présenter le quatrième rapport annuel du ...

International Development Research Centre (IDRC) Digital Library (Canada)

ACCA

savoir autochtone en matière de prévisions météorologiques. ... Le rapport comporte en outre une carte des liens tissés par nos partenaires de recherche avec les décideurs aux échelles locale, nationale et régionale dans le cadre des efforts.

Le paysage anglais: du jardin à la campagne

Directory of Open Access Journals (Sweden)

Gilly LEHMANN

1987-12-01

Full Text Available Le rôle des jardins dans le paysage anglais tient tout autant à ce qui se passe dans les esprits qu'aux réalités concrètes. L'apogée dans la création des jardins et des parcs influant sur le paysage campagnard a lieu au 18e siècle. Les créateurs d'alors visent à construire un paysage idéal; les périodes suivantes proposeront aussi les leurs.

Le patrimoine et ses outils de gestion

CERN Document Server

Garcin, J

2001-01-01

Les principale taches de gestion du Patrimoine immobilier du CERN sont la saisie des données, leur mise à jour, l'archivage et la mise à disposition des informations. Les outils de gestion actuels : Le Système de Gestion de Base de Données Relationnelles alphanumérique ORACLE permet de gérer toutes les informations du Patrimoine, sur le réseau du CERN. Le logiciel de dessin Graphique MICROSTATION (Bentley) a été installé dans la division ST depuis fin 1991. Les plans de situation des sites, des bâtiments et locaux, des espaces confinés ont été réalisés avec ce logiciel. Les outils de demain : La mise en place du SIG (Système d'Information Graphique) STAR a été réalisée en 1993. Le transfert des plans de locaux de MICROSTATION vers STAR est en cours depuis une année environ. Le dessin de la cartographie des réseaux de canalisations Eaux Usées et Eaux Pluviales est en cours de réalisation. Le Web est l'outil de consultation de l'information par les utilisateurs.

Le monde quantique

CERN Document Server

Aspect, A; Bensaude-Vincent, B; Castiel, A; Chevalley, C; Darrigol, O; Deligeorges, S; D'Espagnat, B; Laloë, F; Lévy-Leblond, J-M; Messiah, A; Paty, M; Vuillemin, J; Wheaton, B R

1984-01-01

Le monde quantique La physique quantique, après trois quarts de siècle, n'en finit pas d'être moderne. Elle est présente quotidiennement dans les laboratoires où les physiciens étudient atomes, noyaux et particules. Elle est entrée dans l'industrie où lasers, transistors et supraconducteurs lui doivent d'exister. Et elle continue à alimenter le débat philosophique sur la nature de la réalité dont elle montre la non-séparabilité fondamentale. Ses concepts de base, son développement, ses applications, ses controverses sont ici présentés par une pléiade de physiciens, d'historiens et de philosophes.

Le Pétrole et les dispersants dans les mers baignant le littoral canadien: évaluation des recherches et recommandations

National Research Council Canada - National Science Library

Sprague, John B; Vandermeulen, J. H; Wells, P. G; Birchard, E. C

1982-01-01

...; les methodes d'analyse; les effets du petrole, des dispersants et du petrole disperse chimiquement sur le phytoplancton, les macrophytes, le zooplancton, les poissons, les organismes et animaux benthiques et intertidaux, les oiseaux, les mammiferes marins, les communautes et les ecosystemes. Il comporte certaines recommandations en vue de recherches futures indispensables et donne des conseils sur la facon de minimiser les effets de deversements de petrole dans le milieu marin canadien.

Bioaccumulation of selenium and induced biological effects in the filter feeding bivalve Corbicula fluminea: influence of ventilatory activity, selenium speciation and route of transfer

International Nuclear Information System (INIS)

Fournier, E.

2005-10-01

Selenium is an essential micro-nutrient for most of living organisms. However, toxic effects in several ecosystems have been reported in the literature. Toxicity comprehension is difficult due to the complexity of Se oxidation states in the environment. The aim of this thesis work was to acquire knowledge on the physiological and environmental factors involved in bioaccumulation and toxicity processes in the freshwater filter-feeding bivalve C. fluminea. The aims were: i) to define what the factors involved in Se bioaccumulation processes in the bivalve are, ii) to characterize Se bioaccumulation at different biological organisation levels, iii) to investigate Se toxic effects. First experiments, carried out for short term exposure duration (3 days), have permitted to underline the importance of Se chemical speciation in bioaccumulation processes in C. fluminea. It has been shown that the organic form, seleno-methionine, was much more bio-available than the inorganic forms, selenite and selenate. Moreover, the route of transfer was determinant in those processes. Inorganic forms have been better extracted by trophic route, whereas seleno-methionine has been better extracted by the direct route. In our experimental conditions, ventilation of the bivalve has not been a limiting factor for Se bioaccumulation by the direct route, whereas it has been for bioaccumulation by the trophic route. Ventilation has been largely modified by the presence of dissolved selenite and seleno-methionine. We have shown that the kinetics of seleno-methionine bioaccumulation are much more fast than those of selenite. Moreover, when introduced as SeMet, internalized Se appeared to be relatively remanent in soft tissues of C. fluminea in comparison with Se internalized when introduced as selenite. Subcellular and molecular distributions of these forms were very different. Finally, it has been shown that seleno-methionine and selenite could generate weak alterations of the anti

Le CRDI dans les Philippines

International Development Research Centre (IDRC) Digital Library (Canada)

Le CRDI appuie la recherche dans les. Philippines depuis 1972. Le travail qu'y ont accompli des universités et des instituts de recherche vigoureux et la participation active de la société civile ont entraîné d'importantes améliorations dans les domaines de l'agriculture, du suivi de la pauvreté et de la gestion des forêts.

Un oiseau "sabote" le CERN

CERN Multimedia

Colson, Sébastien

2009-01-01

Un oiseau, un simple oiseau, est parvenu à bloquer à lui tout seul l'accélérateur à particules à 3,7 milliards d'euros. UNe histoire quasiment bulresque qui a toutefois impacté le fonctionnement de la machine durant près de cinq jours, puisque c'est le système de refroidissement qui a été affecté. (1 page)

La nouvelle bourgeoisie islamique. Le modèle turc, de Dilek Yankaya

OpenAIRE

Lelandais, Gülçin Erdi

2016-01-01

De nombreux travaux sur la Turquie contemporaine ont été réalisés ces dernières années en France. La plus grande partie d’entre eux se focalise sur le champ politique et ses évolutions, les minorités ethniques — notamment les Kurdes –, et sur des mobilisations sociales, politiques et environnementales comme la mobilisation autour du parc Gezi. Le livre de Dilek Yankaya ouvre un nouveau champ d’analyse avec sa recherche, pionnière en son genre en France, qui étudie l’émergence d’une nouvelle é...

Modulation of pumping rate by two species of marine bivalve molluscs in response to neurotransmitters: Comparison of in vitro and in vivo results.

Science.gov (United States)

Frank, Dana M; Deaton, Lewis; Shumway, Sandra E; Holohan, Bridget A; Ward, J Evan

2015-07-01

Most studies regarding the neuroanatomy and neurophysiology of molluscan ctenidia have focused on isolated ctenidial tissue preparations. This study investigated how bivalve molluscs modulate their feeding rates by examining the effects of a variety of neurotransmitters, including serotonin, dopamine, and the dopamine agonist apomorphine on both isolated ctenidial tissue and in intact members of two commercially important bivalve species: the blue mussel, Mytilus edulis; and the bay scallop Argopecten irradians. In particular, we examined the effect of changes in: 1) beat of the lateral cilia (in vitro), 2) distance between ctenidial filaments and/or plicae (in vivo), and 3) diameter of the siphonal openings (in vivo) on alteration of bulk water flow through the mantle cavity. Important differences were found between isolated tissue and whole animals, and between species. Drugs that stimulated ciliary beat in vitro did not increase water processing rate in vivo. None of the treatments increased water flow through the mantle cavity of intact animals. Results suggest that A. irradians was primarily modulating lateral ciliary activity, while M. edulis appeared to have a number of ways to control water processing activity, signifying that the two species may have different compensatory and regulatory mechanisms controlling feeding activity. Copyright © 2015 Elsevier Inc. All rights reserved.

Calibration of hydroclimate proxies in freshwater bivalve shells from Central and West Africa

Science.gov (United States)

Kelemen, Zita; Gillikin, David P.; Graniero, Lauren E.; Havel, Holly; Darchambeau, François; Borges, Alberto V.; Yambélé, Athanase; Bassirou, Alhou; Bouillon, Steven

2017-07-01

Freshwater bivalve shell oxygen and carbon stable isotope ratios (δ18O, δ13C) may act as recorders of hydroclimate (e.g., precipitation-evaporation balance, discharge) and aquatic biogeochemistry. We investigate the potential of these hydroclimate proxies measured along the growth axis of shells collected from the Oubangui River (Bangui, Central African Republic) and the Niger River (Niamey, Niger). Biweekly water samples and in situ measurements collected over several years, along with daily discharge data from both sites allowed a direct comparison with proxies recorded in the shells. Data from a total of 14 unionid shells, including three species (Chambardia wissmanni, Aspatharia dahomeyensis, and Aspatharia chaiziana), confirmed that shells precipitate carbonate in oxygen isotope equilibrium with ambient water. Because water temperature variations were small, shell δ18O values (δ18Oshell) also accurately record the seasonality and the range observed in water δ18O (δ18Ow) values when calculated using an average temperature. Calculated δ18Ow values were in good agreement over the entire record of measured δ18Ow values, thus δ18Oshell records can be reliably used to reconstruct past δ18Ow values. Discharge and δ18Ow values from both rivers fit a logarithmic relationship, which was used to attempt reconstruction of past hydrological conditions, after calculating δ18Ow values from δ18Oshell values. A comparison with measured discharge data suggests that for the two rivers considered, δ18Oshell data are good proxies for recording discharge conditions during low(er) discharge levels, but that high discharge values cannot be accurately reconstructed due to the large scatter in the discharge-δ18Ow relationship. Moreover, periods of bivalve shell growth cessation due to high turbidity or air exposure should be taken into account. While δ13C values of dissolved inorganic carbon in both rivers showed clear seasonality and correlated well with discharge

Bioacessibilidade in vitro das biotoxinas marinhas ácido ocadaico, dinofisistoxina-2 e seus derivados em bivalves crus e cozinhados

OpenAIRE

Manita, Diana Filipa Pereira

2017-01-01

Dissertação de Mestrado em Segurança Alimentar As biotoxinas marinhas mais frequentes e abundantes em Portugal são as toxinas lipofílicas, nomeadamente as toxinas do grupo do ácido ocadaico (AO), que inclui as dinofisistoxinas (DTX1 e DTX2) e os seus derivados (DTX3), responsáveis pela intoxicação diarreica (DSP diarrhetic shellfish poisoning). A investigação da presença, variabilidade e transformação de biotoxinas marinhas em moluscos bivalves é de elevada importância não só p...

Le CERN et les Institutions

CERN Document Server

Barbalat, Oscar

1996-01-01

Une première partie de l'exposéŽ sera consacrée àˆ une brève description des principaux organes de l'Union EuropéŽennne: Conseil, Parlement et Commission ainsi que la structure de la Commission. On passera ensuite en revue le Programme-Cadre de Recherche et DéŽveloppement Technologique et les principaux programmes spéŽcifiques auxquels participe le CERN (ESPRIT, ACTS, TMR) On situera ensuite les autres organisations et initiatives scientifiques européŽennes (ESA, ESO, ESRF, JET, ISTC, EUREKA, ...) pour terminer par une brève revue des relations entre le CERN avec ces difféŽrentes institutions en déŽveloppant plus particulièrement celles avec la Commission.

Le nom Škerlj dans le cadre des noms Slovenes actuels

Directory of Open Access Journals (Sweden)

Franc Jakopin

1975-11-01

Full Text Available L'auteur du présent article place le nom Škerlj dans le cadre des noms slovènes actuels qui ont la même constitution phonetique, en éliminant les noms qui, par leur répartition géographique, leurs fréquences et caractéristiques formales, n'entrent pas dans ce cadre. A l'origine du nom Škerlj (et de ses variantes entrent l'appelatif skril (Schiefer et la base d'une onomatopée populaire škrlj (alauda. Par l'énorme force de créer les noms propres de cette derniere nommée, on chercherait l'origine du nom Škerlj surtout dans celle-ci.

Redresser les torts pour préparer un avenir meilleur : Le rôle des ...

International Development Research Centre (IDRC) Digital Library (Canada)

1 févr. 2011 ... Des recherches préliminaires ont déjà été amorcées pour faire la lumière sur ces questions. (De fait, certaines des recherches les plus prometteuses sont nées de la collaboration entre le CRDI et le Centre international pour la justice transitionnelle.) Mais les obstacles qui empêchent de bien comprendre ...

Gestion communautaire des ressources naturelles dans le Parc ...

International Development Research Centre (IDRC) Digital Library (Canada)

En 2002, le Mozambique, l'Afrique du Sud et le Zimbabwe ont signé un accord établissant le Parc transfrontalier du Grand Limpopo (Greater Limpopo Trans Frontier Conservation Area), qui relie entre eux des parcs nationaux des trois pays et un ensemble de terres relevant pour la plupart de régimes fonciers communaux.

Addendum waarde commerciële radiovergunningen

NARCIS (Netherlands)

Poort, J.; Kerste, M.; Akker, I.; Prins, J.

2011-01-01

Op 18 mei 2010 stuurde de Minister van Economische Zaken het SEO-rapport Waarde commerciële radiovergunningen naar de Tweede Kamer. Dat rapport doet verslag van een onderzoek naar de waarde van de commerciële radiovergunningen. Het vormde de grondslag voor het financieel instrument in de

L’interface Habitat / Habitant : quand le lieu de vie est porteur de maladie - Le cas du radon en PACA

Directory of Open Access Journals (Sweden)

Cissé E.

2012-10-01

Full Text Available Les préoccupations sont croissantes pour étudier les liens entre des conditions environnementales spécifiques et la fréquence de certaines pathologies. Nous proposons d’analyser ici le lien présupposé entre une exposition au radon et le cancer du poumon. Le radon, est un gaz radioactif d’origine naturelle (issu de la désintégration naturelle de l’uranium présent dans la croûte terrestre et plus particulièrement dans certaines formations géologiques. A partir du sol et de l’eau, le radon se diffuse dans l’air (exhalation et se trouve, par effet de confinement, à des concentrations plus élevées à l’intérieur des bâtiments qu’à l’extérieur. Les descendants solides du radon sont alors inhalés avec l’air respiré et se déposent dans le poumon. Il est établi par diverses études scientifiques que le radon a un impact non négligeable sur certains cancers, notamment du poumon (augmentation de 16 % du risque de cancer du poumon par tranche de 100 Bq/m3, et des cancers digestifs via la consommation d’eau qui s’est chargée en radon au contact du socle. Le nombre annuel de décès par cancer du poumon attribuable à l’exposition domestique au radon en France métropolitaine varie entre 1 200 à 3 575 en fonction des relations exposition-réponse utilisées. Plusieurs régions en France se caractérisent par une problématique radon reconnue et étudiée depuis longtemps (Bretagne, Massif central, Corse. Or, si le radon ne recouvre pas l’ensemble de la région PACA, certaines zones géographiques sont particulièrement concernées et méritent d’être étudiées : le Massif des Maures dans le Var, du Mercantour dans les Alpes-Maritimes et du Briançonnais dans les Hautes-Alpes. La région PACA est une des régions de France et d’Europe les plus touchées par la pollution atmosphérique principalement due à l’augmentation du trafic routier et des contributions de régions industrialisées telles que

Apprendre ensemble en classe via des jeux vidéo populaires : le modèle du LAN pédagogique

Directory of Open Access Journals (Sweden)

Samuelle Ducrocq-Henry

2011-05-01

Full Text Available La thèse intitulée « Les tribus ludiques» expose le modèle du LAN pédagogique (LP découlant d’une étude des compétitions de jeu vidéo en réseau local (LAN parties. Incarnant un rite de passage quasi tribal chez les 12-25 ans, les LAN semblent favoriser socialisation et apprentissage. Un LP permet aux enseignants d’initier des expériences réseautiques similaires et formatrices en classe, tenues simultanément dans les mondes réels et virtuels, en détournant le scénario de jeux vidéo multijoueurs populaires, pour en faire des simulateurs propices à l’enseignement de disciplines diverses. Sa procédure simple et abordable révèle le potentiel du Serious Gaming en éducation.

Promouvoir le développement durable dans le commerce mondial et les négociations multilatérales

Directory of Open Access Journals (Sweden)

Christophe Bellmann

2011-05-01

Full Text Available Les exportations et les importations mondiales reprennent rapidement du volume après le fort déclin accusé par le commerce de marchandises en 2008-2009, comme l’indiquent les performances du commerce mondial des premier et deuxième trimestres de 2010. En dépit de cette reprise impressionnante, les préoccupations des pays de l’OCDE relatives à l’emploi, à la compétitivité et à la politique chinoise des taux de change ont engendré un climat politique défavorable à la poursuite de la libéralisation dans le cadre du Cycle de Doha. Il est intéressant de noter que les pays en développement qui hésitaient à s’engager dans un nouveau cycle de négociations en 2001 se situent maintenant à l’avant-garde de ceux qui souhaitent parvenir rapidement à une conclusion des pourparlers, bien que le consensus sur l’ambitieux « paquet du développement » envisagé initialement à Doha reste hors d’atteinte. Par ailleurs, le commerce a fait l’objet d’une attention et d’un examen sans précédents dans le cadre des débats sur les changements climatiques. Dans le contexte créé par la crise de la coopération multilatérale, la communauté internationale a un urgent besoin de générer de nouveaux types d’arrangements et de trouver des réponses innovantes aux impératifs du développement et de la transition mondiale vers une économie à faible intensité de carbone.

Le piano touchant/touché: l'instrument du contretemps chez Gide, le cas du Journal et des Notes sur Chopin

OpenAIRE

Zorica Vukušić, Maja

2011-01-01

André Gide, romancier, essayiste, critique et traducteur, a été le diariste dont le journal (écrit de 1887 jusqu`à 1949) est imbibé de musique. Gide a aussi été pianiste – amateur (dans le sens barthésien du terme), tout comme Nietzsche, Sartre ou Barthes. Leur proximité nous est donnée dans une sorte de polémique imaginée qui dépasse le discours. Sans doute Adorno et Jankélévitch ont été meilleurs pianistes et meilleurs philosophes de la musique, mais Gide s`est éloigné de la ...

Rôle du couvre-sol dans le développement du chancre bactérien dans les vergers d’abricotiers

OpenAIRE

Peyre, Manon

2017-01-01

Le genre Pseudomonas, inclut plusieurs espèces de bactéries phytopathogènes, comme les Pseudomonas syringae qui provoque la bactériose, maladie conduisant généralement à la mort des arbres fruitiers. A l’heure actuelle, les moyens de lutte contre P. syringae sont très réduits ou inexistants. Ainsi, des méthodes alternatives ou le rôle de certains éléments comme la présence de réservoirs de la bactérie sont en cours d’étude. Partant de l’hypothèse que le couvre-sol pourrait être une source...

Le modèle périurbain à l’épreuve de la catastrophe

Directory of Open Access Journals (Sweden)

Julien Langumier

2007-05-01

Full Text Available Le modèle périurbain pavillonnaire est questionné à partir d'une démarche ethnographique conduite sur un village du Narbonnais touché par des inondations catastrophiques. L'histoire de ce mode d'urbanisation montre les liens forts qui existent avec les dynamiques territoriales, en l'occurrence la crise viticole des années soixante-dix. L'inondation de 1999 perturbe ensuite les pratiques domestiques et conduit les sinistrés à redéfinir leur mode d'habiter en délaissant le bonheur pavillonnaire au profit de la quête de sécurité. Les discours des gestionnaires connaissent enfin un renversement depuis le développement urbain des campagnes des années quatre-vingt à l'imposition de la "culture du risque" dans ces quartiers à l'avenir incertain. L'approche ethnologique suit les multiples recompositions du modèle périurbain à travers l'histoire d'un territoire, les pratiques des habitants et les discours des gestionnaires.Suburbanisation is about to represent an unsustainable model of urban development for consummating space, energy and equipments. In this context, the tragic floods which affected Cuxac d’Aude village (Aude, France in 1999 can be explained by hazardous choices of planning suburban neighbourhood in risky places. The ethnographical research proposes an other approach which focuses on the bonds with the territory and the residential practices. For the deep wine crises of the 70’s and 80’s in Languedoc, the urbanization of old vineyards participates to the modernization of rural areas. After the floods, the inhabitants define new domestic practices in damaged houses. The suburban villa is no more the modern symbol of happiness but is the place of fear, stress and risk culture.

Centre de recherches pour le développement international ...

International Development Research Centre (IDRC) Digital Library (Canada)

André Lavoie

Definitions. 5. Rôles et ... a) Le Centre de recherches pour le développement international (CRDI) est une société d'État canadienne à .... conduite éthique dans le cadre de ces activités afin que la confiance du public dans .... a) Les gouverneurs en déplacement pour le compte du CRDI ont droit à une indemnité de repas et ...

Le littoral face aux changements climatiques

OpenAIRE

Mulot, Vanessa; Vigneron, Anne-Laure; Lambert-Hadid, Marie-Laure

2011-01-01

Le changement climatique et l’anthropisation du littoral accentuent le risque de submersion marine sur l’ensemble des côtes. Malgré l’élévation en cours du niveau des mers, l’attractivité du littoral ne décroît pas malgré la connaissance du risque. Ce risque aggravera dans les années à venir les enjeux liés à la submersion marine, parmi lesquels le danger pour les vies humaines, comme l’a malheureusement illustré l’actualité (Xynhia), mais aussi la question de la propriété des biens et des te...

Vivre avec ou par le risque à l’île de Sein ?

Directory of Open Access Journals (Sweden)

Annaig Oiry

2012-02-01

Full Text Available L’île de Sein, située au large des côtes finistériennes, fait figure de « territoire du risque » par excellence : cette île basse est confrontée à de fréquentes et violentes tempêtes, la population vit « avec le risque » de submersion depuis des générations tout en voyant la probabilité des aléas catastrophiques augmenter en raison de la carence en aménagement et des conséquences probables du réchauffement climatique. L’image du risque, notamment les photographies de tempête, sert de support à la diffusion d’un sentiment anxiogène justifiant des actions de gestion du risque, mais entretient aussi un sentiment de fascination à l’égard des épisodes tempétueux. Cependant, les îliens portent un regard bien plus critique sur le spectaculaire véhiculé par de telles représentations. Le présent article se penche sur ces rapports entre représentations sociales du risque et iconographie du risque.This article stresses on relationships between hazard’s social representations and iconographies. As an illustration, Sein Island (located near by the Brittany coast, in Finistère. This island is considered as a symbol of natural hazard territory: indeed this low island has been confronted for decades to face significant flood hazard that is nowadays strengthened by the consequences of global warming and a lack of infrastructures. Pictures of flood hazards, and more particularly pictures of storms, are used in order to spread around the fear of natural disasters. This fear justifies the management policies implemented on the island. However islanders criticize pictures which are too spectacular and too distorted. Those gaps between hazard’s representations and iconographies are the main subjects of this article.

Initiative Think tank | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

L'ITT est le fruit d'un partenariat regroupant cinq bailleurs de fonds. Lancée en 2008, l'ITT est administrée par le Centre de Recherches pour le Développement International (CRDI), un organisme canadien.

Reformulation à l’oral et dans le forum Web

Directory of Open Access Journals (Sweden)

Eshkol-Taravella Iris

2016-01-01

Full Text Available Le cadre du travail réalisé entre dans le domaine de la linguistique de corpus et du Traitement Automatique des Langues (TAL. Les recherches sont fondées sur trois corpus : deux corpus oraux (ESLO1 et ESLO2 et un corpus composé de discussions collectées sur un forum de Doctissimo. Le travail vise à détecter, analyser et comparer la reformulation introduite par trois marqueurs (c’est-à-dire, je veux dire et disons dans le discours oral et le corpus écrit dialogique du Web. L’objectif est d’étudier la raison pour laquelle le locuteur décide de modifier un segment par un autre et de repérer un lien formel entre les deux segments reformulés aux différents niveaux linguistiques (morphologique, lexical, syntaxique, etc..

Kuidas kirjutatakse ajalugu? / Jacques Le Goff ; interv. Marek Tamm

Index Scriptorium Estoniae

Le Goff, Jacques

2007-01-01

Prantsuse ajaloolase ja ajakirja Annales ühe peatoimetaja J. Le Goff'i teostest. Varem. ilm.: Ajalugu, antropoloogia ja imaginaarsus : intervjuu Jaques Le Goffiga // Le Goff, Jacques. Raha või elu : majandus ja religioon keskajal. - Tallinn, 2001. - Lk. 108-126

Un’architettura per e con le persone

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Alessandro Rigolon

2011-06-01

Full Text Available L’articolo propone un approccio umanistico al progetto architettonico, ponendo le persone al centro del processo di concezione. Comprendere il modo in cui lo spazio influenza il comportamento, le emozioni e le attività delle persone dovrebbe essere il punto di partenza del progetto. Ciò implica una riflessione sui mezzi con i quali lo spazio trasmette significati connotativi e denotativi. Le tecniche per raccogliere informazioni dagli utenti e per includere tali informazioni nel progetto sono state analizzate per evidenziare i vantaggi e i problemi del mettere in pratica tale approccio umanistico. La discussione finale è focalizzata sulla possibile perdita di autonomia del progettista, sulla tempistica dell’introduzione dei dati derivati dagli utenti e sulle conseguenze dell’inclusione di tali dati nelle normali pratiche progettuali.

Le style modal de la science-fiction

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Emmanuel Boisset

2013-04-01

Full Text Available La faiblesse de style dont souffrirait la science-fiction est en fait le signe que la science y est davantage discours du possible que description du réel. Un « style modal » va suspendre la valeur de vérité, et le style de la possibilité va décontextualiser les métaphores disponibles. En science-fiction, le processus métaphorique génère et structure la diégèse. Un exemple chez Iain M. Banks montre un dialogue quasi incompréhensible mettre à l’épreuve la signification comme possibilité. Les métaphores figées sont revitalisées par la décontextualisation de la fiction, dont le texte peut exploiter l’impertinence.

Rôle des coopératives dans le fonctionnement du bassin de collecte laitier du Tadla, Maroc

OpenAIRE

Le Gal , P.-Y.; Oudin , E.; Kuper , M.; Moulin , C.-H.; Sraïri , T.

2007-01-01

International audience; Le bassin de collecte laitier situé sur le périmètre du Tadla se structure autour d'une usine de transformation industrielle approvisionnée par une myriade de petits éleveurs. Cette atomisation de l'offre a rendu nécessaire la mise en place de coopératives de collecte chargées d'agréger l'offre et d'assurer la chaîne du froid au plus près des producteurs. De fait, ces coopératives jouent un rôle central d'intermédiaire dans la chaîne d'approvisionnement allant de l'eau...

Le « souverain remède » :esquisse d’une érotique libertine dans Le Gascon extravagant

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Michèle Rosellini

2007-06-01

Full Text Available Le Gascon extravagant peut être défini comme roman libertin dans la mesure où il raconte l’éducation érotique de son héros. Ce récit d’éducation suit un mouvement négatif qui, de déception en déconvenue, conduit le personnage à renoncer à toute idéalisation de l’amour et à se borner à la recherche du plaisir. Il retrouve ainsi par son expérience la leçon épicurienne de Lucrèce qui invite à distinguer le pur désir, qui promet le plaisir, de l’amour, qui le plus souvent fait souffrir. Transposée dans le cadre idéologique du roman comique, de tradition gauloise, cette éthique paraît plus cynique que libératrice. Mais le roman n’est pas simple illustration de la philosophie. Par son dispositif narratif et son langage propre, il permet de mettre en débat la morale misogyne du héros-narrateur et de proposer, par-delà toute doctrine, l’exploration d’une expérience du corps encore inédite. C’est par là que le roman comique réalise son ambition, véritablement libertine, d’émanciper le lecteur des préjugés sexuels de son temps et de son milieu.Le Gascon extravagant can be defined as a libertine novel in the measure in which it narrates the erotic education of its hero.  This account of his education follows a negative movement, which, from deception to disappointment, leads the character to renounce all idealized images of love and to confine himself to the search for pleasure.  In so doing, he comes to discover Lucrèce's Epicurean lesson, which invites to distinguish pure desire, wich promises pleasure, and love, wich often brings suffering. Transposed in the ideological framework of the comic novel, of Gauloise tradition, this ethic appears to be more cynical than liberating.  The novel, however, is not a mere illustration of philosophy.  By means of its narrative structure and its own language, it is able to question the misogynous morale of the narrator-hero and to propose, beyond any

Facteurs de risque de l'infection par le VIH dans le district de santé de Meyomessala au Cameroun

Science.gov (United States)

Mbopi-Keou, Francois-Xavier; Nguefack-Tsague, Georges; Kalla, Ginette Claude Mireille; Abessolo, Stéphanie Abo'o; Angwafo, Fru; Muna, Walinjom

2014-01-01

Introduction L'objectif de ce travail était de déterminer les facteurs de risque de l'infection par le VIH dans le district de santé de Meyomessala (Région du Sud) au Cameroun. Méthodes Il s'agissait d'une étude transversale, descriptive et analytique qui s'est déroulée de Février à Mai 2011. Pour cette étude, nous avons obtenu une clairance éthique. Résultats L’échantillon était constitué de 315 participants dont 181 (57,46%) hommes et 134 (42,54%) femmes. L’âge moyen était de 24,5±8ans (extrême: 15-45ans). Quarante personnes (40) étaient séropositifs, soit une prévalence de l'infection par le VIH de 12,7%. Cette prévalence augmentait significativement (p = 0) avec le nombre de partenaires occasionnels au cours des douze derniers mois, allant de 2,7% chez ceux n'ayant eu aucun partenaire occasionnel à 21,25% chez ceux ayant plus de trois partenaires occasionnels (RC = 9,72; IC = 1,27-74,14; P = 0,03). le fait d’être âgé entre 20 et 24 ans (RC = 4,88; IC = 1,74-13,67; p = 0), avoir plus de trois partenaires sexuels au cours des douze derniers mois (RC = 9,72; IC = 1,27-74,14; p = 0,03), avoir les rapports sexuels avec les prostitués (RC = 2,86; IC = 1,42-5,76; p = 0), avoir eu le chlamydia (RC = 3,00; IC = 1,07-8,39; p = 0,04), avoir eu la syphilis (RC = 3,35; IC = 1,57-7,14; p = 0), avoir des avantages sociaux lors du premier rapport sexuel (RC = 2,57; IC = 1,03-6,43; p = 0,04) constituaient des potentiels facteurs de risque du VIH. Conclusion Il apparait urgent d'intensifier les campagnes de sensibilisation au risque d'infection par le VIH et les maladies sexuellement transmissibles dans le district de santé de Meyomessala PMID:25419299

Contester le mariage forcé : mettre en place la ligne de défense et le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le mariage forcé viole les principes de liberté personnelle et d'autonomie individuelle. Il est considéré comme une violation des droits de la personne aux termes du droit international en matière de droits de la personne. Ce projet produira des données probantes qui aideront à combattre le mariage forcé en Inde ...

Differing responses of the estuarine bivalve Limecola balthica to lowered water pH caused by potential CO2 leaks from a sub-seabed storage site in the Baltic Sea: An experimental study.

Science.gov (United States)

Sokołowski, Adam; Brulińska, Dominika; Mirny, Zuzanna; Burska, Dorota; Pryputniewicz-Flis, Dorota

2018-02-01

Sub-Seabed CCS is regarded as a key technology for the reduction of CO 2 emissions, but little is known about the mechanisms through which leakages from storage sites impact benthic species. In this study, the biological responses of the infaunal bivalve Limecola balthica to CO 2 -induced seawater acidification (pH7.7, 7.0, and 6.3) were quantified in 56-day mesocosm experiments. Increased water acidity caused changes in behavioral and physiological traits, but even the most acidic conditions did not prove to be fatal. In response to hypercapnia, the bivalves approached the sediment surface and increased respiration rates. Lower seawater pH reduced shell weight and growth, while it simultaneously increased soft tissue weight; this places L. balthica in a somewhat unique position among marine invertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

Le contrôle de la reproduction chez les poissons.

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CHEVASSUS B.

1979-07-01

Full Text Available L'utilisation de populations monosexes peut permettre d'accroître la rentabilité économique, lorsque la reproduction est trop rapide (aquaculture extensive dans les pays tropicaux ou dans le cas d'espèces où l'un des sexes est plus avantageux (meilleure vitesse de croissance ou maturation plus tardive. Nous avons analysé dans ce papier quatre méthodes permettant la production de populations monosexes. Si l'inversion sexuelle par traitement hormonal ou (a gynogenèse induite (dans le cas d'une homogamétie femelle ne semblent pas directement exploitables, on peut attendre du sexage génétique qui combine ces deux méthodes, des résultats prometteurs. L'hybridation interspécifique peut également conduire à une descendance monosexe dans des cas particuliers.

Le Kongo de Sony Labou Tansi

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Céline Gahungu

2015-02-01

Full Text Available Les textes inédits de Sony Labou Tansi proposent une réflexion sur l’histoire, et plus singulièrement sur celle du Kongo. Le souvenir du prestigieux royaume apparaît dès les premiers manuscrits, composés au début des années 1970. Loin d’être circonscrit aux écrits de jeunesse, le Kongo surgit sous de multiples formes dans le dédale des textes rédigés au cours des années suivantes. Cette fascination pousse l’écrivain dans une dynamique de recherche esthétique : comment évoquer cet illo tempore mythique sans sacrifier à une historicité convenue ? Comment inventer une écriture en mesure de rendre compte du fabuleux royaume ?L’analyse littéraire ne peut cependant faire fi du contexte politique dans lequel Sony Labou Tansi s’inscrit. Outre sa dimension historique et toponymique, Kongo est un ethnonyme dont l’auteur s’est réclamé. Celui-ci a revendiqué à de nombreuses reprises son appartenance à une identité kongo au point de s’être engagé, à la fin des années 1980, dans les rangs du MCDDI1. Ce discours identitaire et l’adhésion à un parti ethnique ont troublé l’image d’un auteur volontiers perçu comme un démocrate véritable. Est-il possible d’articuler le Kongo littéraire et le Kongo politique ? Le Kongo, dont l’ombre portée apparaît dans les manuscrits littéraires mais également dans les articles et les déclarations politiques, pourrait-il nous aider à saisir les enjeux de l’écriture protéiforme de Sony Labou Tansi ?

Fonds d'innovation en vaccins pour le bétail : renforcement des ...

International Development Research Centre (IDRC) Digital Library (Canada)

Fonds d'innovation en vaccins pour le bétail : renforcement des capacités de recherche. Ce projet donne l'autorisation d'appuyer le renforcement des capacités afin de mettre en place le Fonds d'innovation en matière de vaccins pour le bétail et de le gérer. Le Fonds vise à financer le développement de vaccins de qualité ...

Searching the animal psyche with Charles Le Brun.

Science.gov (United States)

Cohen, Sarah R

2010-07-01

Around 1670 the French court painter and Academician Charles Le Brun produced a series of drawings featuring naturalistic animal heads, as well as imaginary heads in which he refashioned various nonhuman animal species to make humanoid physiognomies. What were the purpose and significance of these unusual works? I argue that they show Le Brun's interest in what we today would call animal psychology: focusing upon the sensory organs and their connections with the animal's brain, Le Brun studied his animals as conscious protagonists of the natural realm. One source that may have served him in this project was Marin Cureau de La Chambre's De la Connoissance des bestes of 1645, in which the physician argued that animals possess a conscious soul grounded in the senses. However, Le Brun's animal-humans have no clear place in the artist's taxonomy--nor, indeed, in any seventeenth-century understandings of species. It is rather John Locke, at his most skeptical, who offers the best parallel in the realm of natural philosophy to Le Brun's unsettling animal-humans. Probably without meaning to, Le Brun demonstrated through his eerie, boundary-crossing creatures the limits of visual classification.

En un lugar del aula… De lo que le sucedió a don Quijote en una clase de E/LE

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Luz Celestina Souto

2017-11-01

Full Text Available Resumen: El presente trabajo tiene como objetivo mostrar una vía para la lectura de El ingenioso hidalgo don Quijote de la Mancha en el aula de E/LE. La propuesta se realizará a través de una selección de recursos y actividades sobre el clásico de Cervantes. Las preguntas desde las cuales se parte para el planteamiento son: ¿Qué es un clásico? ¿Por qué leer a Cervantes en la clase de E/LE? ¿Cómo leerlo? ¿Qué ventajas tiene El Quijote en el siglo xxi para quienes tienen el español como segunda lengua? Palabras Clave: Siglo de Oro, Quijote, clase de E/LE, literatura   Abstract: The present work aims to show a way to read El ingenioso hidalgo don Quijote de la Mancha in the E/LE class. The proposal is made through a selection of resources and activities about Cervantes. The questions we ask are: what is a classic? Why read Cervantes in E/LE class? How to read it? What are advantages of  El Quijote in the 21st century for those who have Spanish as a second language? Keywords: Spanish Golden Age, Quixote, E/LE class, literature

Le Chatelier's principle in replicator dynamics

Science.gov (United States)

Allahverdyan, Armen E.; Galstyan, Aram

2011-10-01

The Le Chatelier principle states that physical equilibria are not only stable, but they also resist external perturbations via short-time negative-feedback mechanisms: a perturbation induces processes tending to diminish its results. The principle has deep roots, e.g., in thermodynamics it is closely related to the second law and the positivity of the entropy production. Here we study the applicability of the Le Chatelier principle to evolutionary game theory, i.e., to perturbations of a Nash equilibrium within the replicator dynamics. We show that the principle can be reformulated as a majorization relation. This defines a stability notion that generalizes the concept of evolutionary stability. We determine criteria for a Nash equilibrium to satisfy the Le Chatelier principle and relate them to mutualistic interactions (game-theoretical anticoordination) showing in which sense mutualistic replicators can be more stable than (say) competing ones. There are globally stable Nash equilibria, where the Le Chatelier principle is violated even locally: in contrast to the thermodynamic equilibrium a Nash equilibrium can amplify small perturbations, though both types of equilibria satisfy the detailed balance condition.

Festivals de cinéma dans le monde arabe

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Jean-Michel Frodon

2013-12-01

Full Text Available Alors que les deux grands festivals « historiques » du monde arabe, Carthage (JCC et Le Caire, sont entrés en décadence, on assiste depuis le début des années 2000 à une véritable explosion du phénomène festivalier dans le monde arabe. Le pays le plus en pointe est le Maroc, quoique de manière contrastée, avec une manifestation de prestige à Marrakech, et une nuée de petites manifestations. Dans les émirats du Golfe, la multiplication des festivals traduit une stratégie de communication plutôt qu’une volonté de développement culturel. Cette stratégie est fragilisée par la concurrence que se livrent les différents acteurs. Dans les autres pays arabes, on trouve une grande variété de situations sous le signe de la dispersion. Pourtant, l’accumulation de festivals (une centaine dans la région finit par avoir des effets d’ensemble, au-delà des buts, moyens et limites de chacun d’eux. Le phénomène festivalier, bien qu’inscrit dans des agendas locaux ou nationaux, génère de manière plus vaste des réseaux générationnels, financiers, de procédures d’expertise, de processus d’interrelation, géographiques mais aussi entre le cinéma et les autres arts ou médias.

Effects of anthropogenic sound on digging behavior, metabolism, Ca2+/Mg2+ ATPase activity, and metabolism-related gene expression of the bivalve Sinonovacula constricta

Science.gov (United States)

Peng, Chao; Zhao, Xinguo; Liu, Saixi; Shi, Wei; Han, Yu; Guo, Cheng; Jiang, Jingang; Wan, Haibo; Shen, Tiedong; Liu, Guangxu

2016-01-01

Anthropogenic sound has increased significantly in the past decade. However, only a few studies to date have investigated its effects on marine bivalves, with little known about the underlying physiological and molecular mechanisms. In the present study, the effects of different types, frequencies, and intensities of anthropogenic sounds on the digging behavior of razor clams (Sinonovacula constricta) were investigated. The results showed that variations in sound intensity induced deeper digging. Furthermore, anthropogenic sound exposure led to an alteration in the O:N ratios and the expression of ten metabolism-related genes from the glycolysis, fatty acid biosynthesis, tryptophan metabolism, and Tricarboxylic Acid Cycle (TCA cycle) pathways. Expression of all genes under investigation was induced upon exposure to anthropogenic sound at ~80 dB re 1 μPa and repressed at ~100 dB re 1 μPa sound. In addition, the activity of Ca2+/Mg2+-ATPase in the feet tissues, which is directly related to muscular contraction and subsequently to digging behavior, was also found to be affected by anthropogenic sound intensity. The findings suggest that sound may be perceived by bivalves as changes in the water particle motion and lead to the subsequent reactions detected in razor clams. PMID:27063002

Effects of anthropogenic sound on digging behavior, metabolism, Ca(2+)/Mg(2+) ATPase activity, and metabolism-related gene expression of the bivalve Sinonovacula constricta.

Science.gov (United States)

Peng, Chao; Zhao, Xinguo; Liu, Saixi; Shi, Wei; Han, Yu; Guo, Cheng; Jiang, Jingang; Wan, Haibo; Shen, Tiedong; Liu, Guangxu

2016-04-11

Anthropogenic sound has increased significantly in the past decade. However, only a few studies to date have investigated its effects on marine bivalves, with little known about the underlying physiological and molecular mechanisms. In the present study, the effects of different types, frequencies, and intensities of anthropogenic sounds on the digging behavior of razor clams (Sinonovacula constricta) were investigated. The results showed that variations in sound intensity induced deeper digging. Furthermore, anthropogenic sound exposure led to an alteration in the O:N ratios and the expression of ten metabolism-related genes from the glycolysis, fatty acid biosynthesis, tryptophan metabolism, and Tricarboxylic Acid Cycle (TCA cycle) pathways. Expression of all genes under investigation was induced upon exposure to anthropogenic sound at ~80 dB re 1 μPa and repressed at ~100 dB re 1 μPa sound. In addition, the activity of Ca(2+)/Mg(2+)-ATPase in the feet tissues, which is directly related to muscular contraction and subsequently to digging behavior, was also found to be affected by anthropogenic sound intensity. The findings suggest that sound may be perceived by bivalves as changes in the water particle motion and lead to the subsequent reactions detected in razor clams.

Effects of anthropogenic sound on digging behavior, metabolism, Ca2+/Mg2+ ATPase activity, and metabolism-related gene expression of the bivalve Sinonovacula constricta

Science.gov (United States)

Peng, Chao; Zhao, Xinguo; Liu, Saixi; Shi, Wei; Han, Yu; Guo, Cheng; Jiang, Jingang; Wan, Haibo; Shen, Tiedong; Liu, Guangxu

2016-04-01

Anthropogenic sound has increased significantly in the past decade. However, only a few studies to date have investigated its effects on marine bivalves, with little known about the underlying physiological and molecular mechanisms. In the present study, the effects of different types, frequencies, and intensities of anthropogenic sounds on the digging behavior of razor clams (Sinonovacula constricta) were investigated. The results showed that variations in sound intensity induced deeper digging. Furthermore, anthropogenic sound exposure led to an alteration in the O:N ratios and the expression of ten metabolism-related genes from the glycolysis, fatty acid biosynthesis, tryptophan metabolism, and Tricarboxylic Acid Cycle (TCA cycle) pathways. Expression of all genes under investigation was induced upon exposure to anthropogenic sound at ~80 dB re 1 μPa and repressed at ~100 dB re 1 μPa sound. In addition, the activity of Ca2+/Mg2+-ATPase in the feet tissues, which is directly related to muscular contraction and subsequently to digging behavior, was also found to be affected by anthropogenic sound intensity. The findings suggest that sound may be perceived by bivalves as changes in the water particle motion and lead to the subsequent reactions detected in razor clams.

Hypoxia and acidification have additive and synergistic negative effects on the growth, survival, and metamorphosis of early life stage bivalves.

Science.gov (United States)

Gobler, Christopher J; DePasquale, Elizabeth L; Griffith, Andrew W; Baumann, Hannes

2014-01-01

Low oxygen zones in coastal and open ocean ecosystems have expanded in recent decades, a trend that will accelerate with climatic warming. There is growing recognition that low oxygen regions of the ocean are also acidified, a condition that will intensify with rising levels of atmospheric CO2. Presently, however, the concurrent effects of low oxygen and acidification on marine organisms are largely unknown, as most prior studies of marine hypoxia have not considered pH levels. We experimentally assessed the consequences of hypoxic and acidified water for early life stage bivalves (bay scallops, Argopecten irradians, and hard clams, Mercenaria mercenaria), marine organisms of significant economic and ecological value and sensitive to climate change. In larval scallops, experimental and naturally-occurring acidification (pH, total scale  = 7.4-7.6) reduced survivorship (by >50%), low oxygen (30-50 µM) inhibited growth and metamorphosis (by >50%), and the two stressors combined produced additively negative outcomes. In early life stage clams, however, hypoxic waters led to 30% higher mortality, while acidified waters significantly reduced growth (by 60%). Later stage clams were resistant to hypoxia or acidification separately but experienced significantly (40%) reduced growth rates when exposed to both conditions simultaneously. Collectively, these findings demonstrate that the consequences of low oxygen and acidification for early life stage bivalves, and likely other marine organisms, are more severe than would be predicted by either individual stressor and thus must be considered together when assessing how ocean animals respond to these conditions both today and under future climate change scenarios.

Le mal et ses complots imaginaires

OpenAIRE

Frankfurter, David

2012-01-01

Les récits d’abus rituels sataniques que les médias ont largement diffusés, aux États-Unis et au Royaume-Uni, entre le début des années 1980 et la fin des années 1990, soutenaient le parallèle avec les allégations avancées, durant l’Antiquité et au début des Temps modernes, contre les chrétiens, les hérétiques, les juifs ou les sorcières. Quelle est la nature de ces parallèles ? Cet article examine plusieurs types de modèles convoqués lors de diverses occurrences historiques des peurs panique...

Les nouveaux mécanismes du contrôle organisationnel

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Rosimeri Carvalho da Silva

Full Text Available Dans cet essai on discute les mécanismes de contrôle mis en évidence par l'adoption de nouvelles technologies de gestion qui ont proporcionné une restructuration productive. La relevance de cette discussion est dans la compréhension que l'adoption de ces nouvelles technologies impliquent des alterations dans le système de contrôle que, même si elles ne remplacent pas complètement les modes de contrôle utilisés avant, mettent l'accent sur un mode de contrôle plus subtil que privilegie des mécanismes qu'influencient le partage d'une vision de monde.

Publications | Page 160 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

africain. Il y a deux ans, le Centre de recherches pour le développement ... African Youth on the Information Highway : Participation and Leadership in Community Development. Tout comme elle l'a fait dans le Nord industrialisé, la révolution de ...

Publications | Page 162 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

africain. Il y a deux ans, le Centre de recherches pour le développement ... African Youth on the Information Highway : Participation and Leadership in Community Development. Tout comme elle l'a fait dans le Nord industrialisé, la révolution de ...

Concepteur Web | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Gérer l'ensemble du cycle de conception, y compris l'architecture technique, le plan du site, l'interface de l'utilisateur, la conception de la base de données, toute la programmation et la documentation. Effectuer l'évaluation des besoins, la création de prototypes, la conception, le codage, les essais et le débogage. Définir et ...

Le consentement libre et éclairé aux soins en psychiatrie

Science.gov (United States)

Neilson, Grainne; Chaimowitz, Gary

2015-01-01

Résumé Le patient a le droit d’être informé sur les soins de santé qui lui sont proposés et de participer activement à la prise de décisions relativement à ces soins. Le respect de la dignité et de l’autonomie de la personne passe par le respect de son droit de prendre des décisions à propos de ses soins psychiatriques, notamment de refuser un traitement, pour autant qu’elle soit apte à prendre des décisions. Il importe que le psychiatre connaisse les fondements éthiques du consentement libre et éclairé et les exigences prévues par le droit en cette matière, y compris la jurisprudence. Le consentement n’est pas immuable, pouvant changer avec le temps, au fil de l’évolution des conditions et des circonstances. Par conséquent, le consentement doit être un processus continu.

Image du savoir, image du pouvoir dans le Lapidaire

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Marta LACOMBA

2007-01-01

Full Text Available À travers le prologue et les enluminures de présentation, le Lapidaire d’Alphonse X oriente l’interprétation de l’œuvre. Ces paratextes mettent en avant le rôle capital du savoir, représenté par la métaphore du trésor caché, qui a ici une valeur topique. Ils mettent également en exergue le rôle que s’attribue le roi dans la transmission de ce savoir, et placent cette nouvelle attribution royale au cœur de son projet politique.A través del prólogo y las miniaturas de presentación, el Lapidario de Alfonso X orienta la interpretación de la obra. Estos paratextos subrayan el papel capital del saber, representado por la metáfora del tesoro escondido, que tiene aquí un valor tópico. Ponen asimismo de manifiesto el papel que se atribuye el monarca en la transmisión de ese saber y colocan esta nueva atribución real en el centro de su proyecto político.

Le language des masques burkinabè

African Journals Online (AJOL)

hond

2 juil. 2007 ... un faire transformateur cognitif devient un esprit qui a des fonctions hautement spirituelles, religieuses et aussi souvent esthétiques. Le langage et le discours des masques. Les masques sont un langage et un discours. Un langage est un système de communi- cation et d'expression. L'unité de base de ...

Le désordre du monde

African Journals Online (AJOL)

sulaiman.adebowale

Le début du XXIe siècle se caractérise par l'accumulation et la consécution ..... Unis a présidé à la naissance aux forceps de cet outil d'équilibre du monde en ... De toute évidence, l'ONU reste l'instrument qui a marqué le siècle dernier,.

Georges et le big bang

CERN Document Server

Hawking, Lucy; Parsons, Gary

2011-01-01

Georges et Annie, sa meilleure amie, sont sur le point d'assister à l'une des plus importantes expériences scientifiques de tous les temps : explorer les premiers instants de l'Univers, le Big Bang ! Grâce à Cosmos, leur super ordinateur, et au Grand Collisionneur de hadrons créé par Éric, le père d'Annie, ils vont enfin pouvoir répondre à cette question essentielle : pourquoi existons nous ? Mais Georges et Annie découvrent qu'un complot diabolique se trame. Pire, c'est toute la recherche scientifique qui est en péril ! Entraîné dans d'incroyables aventures, Georges ira jusqu'aux confins de la galaxie pour sauver ses amis...Une plongée passionnante au coeur du Big Bang. Les toutes dernières théories de Stephen Hawking et des plus grands scientifiques actuels.

The bivalve Anopaea (Inoceramidae) from the Upper Jurassic-lowermost Cretaceous of Mexico

Science.gov (United States)

Zell, Patrick; Crame, J. Alistair; Stinnesbeck, Wolfgang; Beckmann, Seija

2015-07-01

In Mexico, the Upper Jurassic to lowermost Cretaceous La Casita and coeval La Caja and La Pimienta formations are well-known for their abundant and well-preserved marine vertebrates and invertebrates. The latter include conspicuous inoceramid bivalves of the genus Anopaea not formally described previously from Mexico. Anopaea bassei (Lecolle de Cantú, 1967), Anopaea cf. stoliczkai (Holdhaus, 1913), Anopaea cf. callistoensis Crame and Kelly, 1995 and Anopaea sp. are rare constituents in distinctive Tithonian-lower Berriasian levels of the La Caja Formation and one Tithonian horizon of the La Pimienta Formation. Anopaea bassei was previously documented from the Tithonian of central Mexico and Cuba, while most other members of Anopaea described here are only known from southern high latitudes. The Mexican assemblage also includes taxa which closely resemble Anopaea stoliczkai from the Tithonian of India, Indonesia and the Antarctic Peninsula, and Anopaea callistoensis from the late Tithonian to ?early Berriasian of the Antarctic Peninsula. Our new data expand the palaeogeographical distribution of the high latitude Anopaea to the Gulf of Mexico region and substantiate faunal exchange, in the Late Jurassic-earliest Cretaceous, between Mexico and the Antarctic Realm.

Le Corbusier, Alfred Roth y el color

Directory of Open Access Journals (Sweden)

Angelica Fernández-Morales

2014-07-01

Full Text Available This article discusses the relationship between Le Corbusier and Alfred Roth, a member of the Paris office between 1927 and 1928. It also deals with the influence that this period had with reference to an important factor in Roth’s professional development, as in Le Corbusier’s later works: the use of colour in his architecture. This article takes the position that Roth, given his close friendship with Mondrian, was an important figure in turning Le Corbusier’s work towards greater use of primary colours and aesthetic neoplasticism.

Le rôle de paysans mieux informés au Bénin | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

10 déc. 2010 ... Le défi : faire face au chaos climatique. Au Bénin, le secteur agricole constitue environ 36 % du PIB et représente près de 88 % des recettes d'exportation, en plus de satisfaire à la demande locale. Cependant, ce secteur est menacé. Loin d'être la seule cause du sous-développement, les bouleversements ...

La gentrification et ses pionniers : le rôle des artistes off en question

Directory of Open Access Journals (Sweden)

Elsa Vivant

2008-09-01

Full Text Available Cet article propose d’évaluer le rôle des artistes, et plus particulièrement des squats d’artistes, dans la gentrification. La littérature anglo-saxonne insiste en effet beaucoup sur le rôle déterminant de l’arrivée d’artistes plus ou moins marginaux (ceux de la scène dite off dans le déclenchement de la gentrification d’un quartier. Ces artistes sont considérés non seulement comme des initiateurs de la revalorisation symbolique des quartiers qu’ils investissent, mais aussi comme des ferments d’un changement d’ambiance qui permettrait l’arrivée de gentrifieurs plus aisés. Cet article met à l’épreuve ce schéma explicatif à partir de l’étude du cas de Belleville à Paris. Il mobilise pour ce faire deux enquêtes, l’une sur le rapport à leur quartier des habitants de deux rues particulièrement gentrifiées, l’autre sur le marché immobilier. Il apparaît que les artistes sont plus des témoins ou des indicateurs de la gentrification que des déclencheurs ou des catalyseurs. Ils sont partie prenante d’un mouvement de revalorisation de la centralité et de ses ressources (notamment culturelle qui les dépassent. Ce mouvement les dépasse d’autant plus que l’éthique « artiste » s’est largement diffusée dans toutes les couches de la société.This article aims at reassessing the role of artists, and more specifically the role of squatters in the gentrification process. The Anglo-American literature argues that artists influx, especially the underground ones (that we call off, is the key element to trigger the gentrification process in a neighbourhood. These artists are considered as pioneers of the symbolic revalorisation process and as the agent of atmosphere change that brings wealthier gentrifiers to settle down. This article reassesses this scheme, based on the case of Belleville neighbourhood in Paris. It relies on two pieces of researches.  The first one analyses the inhabitants�

Le devenir actif du corps affectif

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Pascal Séverac

2005-09-01

Full Text Available Le but de cet article est de saisir ce que signifie, pour le corps, être actif. À partir de la proposition 49 de la partie IV de l’Éthique, on propose de distinguer deux manières d’appréhender le corps – soit comme corps organique, soit comme corps affectif -, et l’on montre que la question éthique du devenir actif s’adresse à la dimension affective du corps. Il faut penser le devenir actif du corps affectif comme augmentation de son aptitude non seulement à affecter, mais aussi à être affecté. En effet, être affecté pour le corps n’est pas identique à pâtir : au contraire, plus est grande l’ouverture sensible d’un corps aux autres corps, plus est grande son activité éthique.The aim of this paper is to understand how the body can be active. With the proposition 49 of the fourth part of Ethics, two ways of conceiving of the body are distinguished : like an organic body or like an affective body. The ethics question of becoming active is about the affective body. This becoming active must be understood as increasing of the ability to affect, as well as to be affected. To be affected is different from to be passive. On the contrary, the more the body is able to be affected, the more he becomes active.

Plaidoyer pour le lavage de nez dans les pathologies naso ...

African Journals Online (AJOL)

Le lavage de nez permet l'humidification des muqueuses partant favorise le nettoyage mucociliaire en enlevant voire diminuant les croutes favorise leur élimination et ainsi la guérison en réduisant le recours aux antibiotiques [4-10]. Sans danger, le lavage de nez est bien tolérée tant chez les enfants que chez les adultes.

Pour mieux profiter des avantages commerciaux : le Réseau latino ...

International Development Research Centre (IDRC) Digital Library (Canada)

2011-07-13

Pour mieux profiter des avantages commerciaux : le Réseau latino-américain sur le commerce. July 13, 2011. Image. Kevin Conway. Éloigner les menaces et maximiser les possibilités : voilà le mantra des négociateurs commerciaux de par le monde. Pour que la stratégie réussisse, toutefois, les négociateurs et leurs ...

Le rôle de l'énergie dans le développement rural | CRDI - Centre de ...

International Development Research Centre (IDRC) Digital Library (Canada)

21 oct. 2010 ... L'énergie est sans aucun doute l'un des principaux moteurs du ... de ses recherches sur l'énergie, l'environnement et le développement rural. ... Durban, Mumbai et Rio illustrent la croissance rapide et la transformation qui a ...

Viollet-le-Duc ou la caricature au cour du style

OpenAIRE

Linford, Sarah

2014-01-01

« Il y a le style ; il y a les styles. » Ainsi commence l’un des articles phares du Dictionnaire raisonné de l’architecture française du XIe au XVIe siècle, d’Eugène-Emmanuel Viollet-le-Duc. L’article sur le style paraît dans le huitième tome, en 1868, quatorze ans après la publication du premier. Article de maturité, il constitue un condensé de la pensée de Viollet-le-Duc et révèle certaines clefs de voûte de son système. « Les styles sont les caractères qui font distinguer entre elles les é...

Chapitre 2. Le texte dérivé

OpenAIRE

2017-01-01

Les analyses précédentes indiquent qu’il est difficile de séparer une poétique de l’écriture ou de la réécriture, procès toujours prospectif, de celle du texte. En effet, le texte est aussi le résultat d’une activité poétique. Mais les conceptions de la notion de texte ne sont pas des plus univoques. Appliquées à la réécriture filmique des textes littéraires, elles le sont encore moins. Comment en serait-il autrement ? Le film lui-même, considéré comme production sémiotique, ne semble pas pou...

Le CRDI au Népal

International Development Research Centre (IDRC) Digital Library (Canada)

Au cours des années 1980 et 1990, les recherches menées dans le domaine de la phytosélection ont donné lieu à l'amélio- ration du rendement de céréales telles que le mil et l'orge. Par la suite, d'autres activités de recherche ont rendu les agriculteurs mieux en mesure de préserver la diversité génétique de leurs cultures ...

Le colonel Rol-Tanguy

OpenAIRE

Bourderon, Roger

2009-01-01

Ouvrier métallurgiste, syndicaliste et communiste, le futur colonel Rol-Tanguy, né en 1908, se passionne pour le métier des armes lors de son service militaire. Son expérience dans les Brigades internationales est décisive. Il l’enrichit dans les FTP puis comme chef régional FFI : il prépare et conduit l’insurrection parisienne avec un état-major comportant de nombreux cadres de l’armée. Compagnon de la Libération, il se distingue dans la campagne d’Allemagne et est intégré dans l’armée avec ...

Le Brahmane du Komintern

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Elizabeth Burgos

2008-01-01

Full Text Available Le Brahmane du Komintern, largometraje documental del realizador francés Vladimir León, constituye un ejercicio ejemplar de investigación histórica y  de lograda factura de realización. Y, pese a no haber contado con la ayuda de ninguno organismo público, se trata de un ambicioso proyecto que cubre una amplia extensión geográfica que abarca: Estados Unidos, México, Moscú, Berlín, y la India. Gira en torno a una figura que tuvo en su tiempo su hora de gloria. Un bengalí, hijo de braman, la c...

Quand la musique donne le ton

DEFF Research Database (Denmark)

Reeh, Henrik

2017-01-01

Le lycée Sainte-Anne de Copenhague est un établissement réputé pour les résultats de ses élèves et pour être le foyer d’une intense tradition chorale et musicologique. L’article interroge les parcours de 32 élèves d’une même classe, tous reçus au baccalauréat 2014 avec une option musique et mathé...... de comprendre cette coexistence entre musique et éducation, la relation entre « individu » et « communauté » est examinée et la notion de « culture » désigne le point d’articulation qui peut rendre compte de la dynamique pédagogique en question....

Le chaos et l'harmonie la fabrication du Réel

CERN Document Server

Xuan Thuan, Trinh

1998-01-01

Cette fin de siècle a vu un véritable bouleversement dans notre façon de concevoir le monde. Après avoir dominé la pensée occidentale pendant trois cents ans, la vision newtonienne d'un univers fragmenté, mécaniste et déterministe a fait place à celle d'un monde exubérant de créativité. Le Réel n'est plus déterminé seulement par des lois naturelles appliquées à des conditions initiales particulières, mais aussi moulé et façonné par une suite d'événements contingents et historiques qui peuvent bouleverser la réalité à son niveau le plus profond. Celui du bolide rocailleux venu percuter la Terre il y a quelque 65 millions d'années et responsable de la mort des dinosaures en est un exemple. Les lois physiques ont perdu leur rigidité. Avec l'avènement de la mécanique quantique, le hasard est entré en force dans le monde subatomique. Le monde macroscopique n'a pas été épargné. Avec la théorie du chaos, le hasard et le non-déterminisme ont envahi non seulement la vie de tous le...

L’investiture du 44e président des Etats-Unis :Le National Mall, le village global et le Green New Deal

Directory of Open Access Journals (Sweden)

Cynthia Ghorra-Gobin

2009-02-01

Full Text Available Ce texte sur les Etats-Unis est le dernier article d’une série de trois rédigés au fur et à mesure des événements à l’occasion de la 56e élection présidentielle qui a marqué l’avènement du 44e président, Barack Obama. Le premier article (juin 2008, « Un événement révélateur des mutations de la société américaine » soulignait l’originalité du sénateur candidat Obama à l’élection présidentielle de 2008 en raison de son parcours personnel face à son rival McCain. Le deuxième article (novembre 2008 « Le regard des Américains dans un contexte mondial incertain », mettait en évidence les valeurs symboliques véhiculées par le futur président Obama dans une société qui avait choisi de clore son histoire raciale. Ce troisième article s’appuyant principalement sur les images de la cérémonie d’investiture du 20 janvier 2009, le discours du président Obama et quelques commentaires des médias rend compte du sentiment de joie et de fierté d’un peuple en dépit d’une prise de conscience de la gravité d’une crise financière et économique (sans oublier les deux guerres en cours. Il illustre le choix du président en faveur d’une politique a priori en rupture avec celle de l’administration précédente en prenant l’exemple du changement climatique. Toutefois il s’interroge sur la pertinence de l’expression  « Green New Deal »  avancée par les médias en dehors de toute référence à la notion d’empreinte écologique et d’un regard réflexif sur l’American Way of Life.  This third article mainly based on the images of the inauguration ceremony (January 20th, on the president Obama’s discourse and on a few comments made by the media, describes the feeling of happiness and prideness as expressed by the American people on the National Mall in spite of the seriousness of the financial and economic crises (besides two wars. It also illustrates the choice of a president

La communication participative pour le développement : Un agenda ...

International Development Research Centre (IDRC) Digital Library (Canada)

1 janvier 1996. ISBN : Épuisé. 138 pages. e-ISBN : 1552503909. Téléchargez le PDF. Il y a deux ans, le Centre de recherches pour le développement international a créé CIME, un programme de communication pour le développement, afin de témoigner de l'importance des interrelations entre la Communication à la base, ...

Ombres du Grand Inquisiteur de Dostoïevski dans le Zéro et l’Infini de Koestler : entre Dieu et le diable

Directory of Open Access Journals (Sweden)

Orlane Glises de la Rivière

2014-12-01

Full Text Available À plusieurs égards, Ivan Karamazov, l’intellectuel des trois frères du roman de Fiodor Dostoïevski, peut se rapprocher du personnage d’Ivan du roman Le Zéro et l’infini d’Arthur Koestler. En effet, tous deux sont liés à la légende du Grand Inquisiteur, symbole d’un totalitarisme tout-puissant qui pactise avec le diable, mais qui, néanmoins, attend une réponse d’un Dieu demeuré muet. De raisonnements politiques en questionnements théologiques, les deux romans mettent trois grands personnages en lumière : le Grand Inquisiteur, le diable et le Christ. Tous trois se distinguent au cours du dialogue entre Roubachof et Ivanof dans le roman d’Arthur Koestler et traitent des problématiques qui tissent le roman de Fiodor Dostoïevski. Issues d’une quête vers Dieu, elles trahissent pourtant l’absence criante de foi d’Ivan et d’Ivanof. Ou plus exactement d’une « recherche désespérée de foi » telle que la décrivait Koestler dans son roman Les hommes ont soif. Cet article tend à montrer comment cette recherche se manifeste et à quelle réponse les personnages sont confrontés.

Rapports annuels | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Rapports annuels. Le CRDI publie un rapport annuel dans lequel il présente ses états financiers et ses résultats. Ce rapport met en outre en évidence des chercheurs bénéficiaires de subventions du CRDI et en décrit les projets et les réalisations clés. C'est le principal outil par lequel le Centre rend compte de ses activités ...

Le regard anachronique

Directory of Open Access Journals (Sweden)

Jean-Paul Aubert

2011-01-01

Full Text Available Cet article a pour objet l’anachronisme dans le film historique. Il s’appuie sur l’étude du long métrage Goya à Bordeaux, réalisé en 1999 par le cinéaste espagnol Carlos Saura. Cette biographie filmée du peintre Francisco de Goya fait mieux que composer avec l’anachronisme inhérent à toute reconstitution historique. Il l’assume et le revendique. La mise en cause de la chronologie et l’effacement de l’Histoire prennent sens dans la perspective d’une réflexion originale sur l’Histoire de l’art conçue comme un dialogue entre les œuvres et entre les époques.Este artículo está dedicado al problema del anacronismo en las películas históricas. Se basa en el estudio de Goya en Burdeos, un largo metraje rodado en 1999 por el director de cine español Carlos Saura. Esta biografía de Goya no sólo se acomoda con el anacronismo propio de la reconstitución histórica sino que lo asume y lo reivindica. El cuestionamiento de la cronología y el desinterés por la Historia cobran un nuevo sentido en el marco de una reflexión original sobre la Historia del arte concebida como un diálogo entre las obras y entre las épocas.

Publications | Page 173 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

E-Commerce in the Asian Context : Selected Case Studies. Le commerce électronique en Asie retient beaucoup l'attention en raison de la prolifération des connexions Internet et des technologies connexes dans la région. Face à cette tendance, le Centre de recherches pour le développement international (.

All rates are effective 15 October 2017 / En vigueur le 15 octobre ...

International Development Research Centre (IDRC) Digital Library (Canada)

15 oct. 2017 ... 324. POLAND / POLOGNE. Everywhere / Dans tout le pays. 363. PORTUGAL. Everywhere / Dans tout le pays. 457. PUERTO RICO / ÉTAT LIBRE DE PORTO RICO. Everywhere / Dans tout le pays. 366. QATAR. Everywhere / Dans tout le pays. 590. ROMANIA / ROUMANIE. Everywhere / Dans tout le pays.

9 décembre 2016 - Visite du hall d'assemblage des aimants supraconducteurs du LHC par le Prof. D. Le Bihan, Directeur, NeuroSpin; membre de l’Académie des Sciences, République française avec le Directeur des accélérateurs et de la technologie F. Bordry et le chef de groupe L. Bottura.

CERN Multimedia

Bennett, Sophia Elizabeth

2016-01-01

9 décembre 2016 - Visite du hall d'assemblage des aimants supraconducteurs du LHC par le Prof. D. Le Bihan, Directeur, NeuroSpin; membre de l’Académie des Sciences, République française avec le Directeur des accélérateurs et de la technologie F. Bordry et le chef de groupe L. Bottura.

Développement du logiciel de contrôle de Vertex Locator

CERN Document Server

Mennane, M

2005-01-01

L’expérience LHCb, qui consiste à mettre en collision deux faisceaux de particules pour en observer les phénomènes résultants, est dotée d’un système de contrôle fondé sur l’utilisation du logiciel PVSS et d’un système client-serveur. PVSS permet à l’utilisateur du détecteur de gérer par le biais d’une interface graphique toute l’électronique. Le système client-serveur intégré à PVSS, appelé DIM, offre quant à lui la possibilité de configurer et de surveiller le détecteur à partir d’un ordinateur quelconque. Toute une chaîne de contrôle a été conçue pour le Vertex Locator, détecteur le plus proche du point de collision permettant de reconstituer la trajectoire des particules issues de l’impact. Deux cartes électroniques sont au coeur de la chaîne de contrôle du Vertex Locator : le control board qui permet d’envoyer via I2C des commandes de configuration aux composants et de distribuer des signaux de synchronisation, et le temperature board qui permet de veil...

« Le souvenir de la nature dans le sujet ». Une actualité de La Dialectique de la raison

Directory of Open Access Journals (Sweden)

Gilles Moutot

2010-09-01

Full Text Available On se propose de montrer que le « souvenir de la nature dans le sujet », un des thèmes majeurs de La Dialectique de la raison, trouve une actualité spécifique dans certains débats et travaux contemporains. Dans la mesure où elle est pensée sous la condition de la remémoration, et donc de son intrication avec l’histoire, l’expérience que le sujet peut faire de la nature en lui apparaît nouée à une visée critique et normative qui cependant se garde de toute surcharge naturaliste (telle qu’elle s’aperçoit par exemple dans les diverses conceptions d’une nature-modèle : contre la violence des identités socialement contraintes, il s’agit de prêter attention à ce qui atteste, à même les impulsions somatiques, le lien entre aspiration à la liberté et souci de ce dont on ne peut disposer (en termes adorniens, le « non-identique ». Une telle approche est susceptible d’éclairer les prolongements actuels de la Théorie critique, par exemple là où celle-ci s’efforce de penser les souffrances sociales.

Le modèle standard de la physique des particules de l'électron au boson de Higgs

CERN Document Server

Samueli, Jean-Jacques

2013-01-01

Le modèle standard de la physique des particules est une théorie qui décrit les constituants élémentaires de la matière et les interactions qui existent entre eux. Le présent ouvrage est un exposé du développement historique de ce modèle qui suppose que toute la matière est composée de quarks et de leptons, particules ponctuelles de spin 1?2. On dénombre trois générations de quarks et autant de leptons. Les interactions faible, forte et électromagnétique sont, pour leur part, décrites par des théories de jauge dont la médiation est effectuée par des quanta de jauge de spin 1. Ces médiateurs sont les ? , W + , W ? , Z ainsi que huit gluons. La gravitation est par ailleurs analysée dans l'ouvrage dans sa formulation classique et relativiste. Enfin le mécanisme dit de Englert-Brout-Higgs prévoit des particules de spin zéro, correspondant à un champ scalaire qui est supposé donner une masse aux quarks, leptons et aux bosons vecteurs intermédiaires W + , W ? , Z . Nous décrivons ce m�...

The Role of the State | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

1 mars 2013 ... Voici le premier ouvrage d'une collection qui en comptera cinq et qui colligera les résultats de recherches intensives sur les systèmes d'innovation nationaux dans les pays BRICS : le Brésil, la Russie, l'Inde, la Chine et l'Afrique du Sud. The Role of the State analyse le rôle de l'État dans le déploiement de ...

Kenya | CRDI - Centre de recherches pour le développement ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le Kenya est depuis longtemps le centre économique de l'Afrique de l'Est. Cependant, malgré des progrès économiques considérables au cours de la dernière décennie, la pauvreté et des inégalités persistent. Le bureau du CRDI à Nairobi est le point central des efforts du Centre en Afrique subsaharienne et il supervise ...

Sept brèves leçons de physique

CERN Document Server

Rovelli, Carlo

2015-01-01

Avec les mots de l écrivain, le talent du poète, Carlo Rovelli nous fait apercevoir le mystère du monde, la beauté du monde, une beauté à couper le souffle. Ces « sept leçons » donnent un aperçu rapide des aspects les plus importants et fascinants de la grande révolution qui a bouleversé la physique au xxe siècle, et surtout des questions et des mystères que cette révolution a soulevés. Elles nous emmènent dans le monde enchanté des grandes idées de la physique actuelle : de la relativité générale d Einstein à la physique quantique, des particules élémentaires à l architecture de l Univers, de la gravité quantique à la nature du temps et de la conscience. Un éblouissement ! Traduit en vingt-quatre langues, les Sept brèves leçons de physique sont un best-seller mondial.

Le français de la communication professionnelle

CERN Document Server

Danilo, Michel; Lincoln, M

A partir de 150 heures de français. - Pour acquérir une bonne maîtrise des pratiques professionnelles. - Pour améliorer ses connaissances de la langue tout en se familiarisant avec les pratiques langagières spécifiques du monde du travail. - Pour préparer les examens de la Chambre de Commerce et d'Industrie de Paris. Dix dossiers : - La communication dans les affaires - Le travail administratif - Le téléphone - La communication interne - Le courrier de l'entreprise - L'offre et la commande - Livraison, transport, assurance - La facturation et le règlement - La communication avec les partenaires - Les nouveaux outils de communication Une cassette audio ainsi que des corrigés accompagnent ce livre.

J.M. Barrie : Les masques de Jacobus Hook Partie I/II : Le Capitaine Hook à Eton ou Le Solitaire1

OpenAIRE

Faivre, Céline-Albin

2013-01-01

Cette causerie n’aurait pas lieu si le Doyen ne m’avait pas lancé un défi. Je me trouvai ici le 4 juin dernier, lorsque, pendant le déjeuner, au beau milieu de son discours, le Doyen me mit au défi de réfuter cette terrible accusation : « James Hook, le Capitaine pirate, était un grand mais non pas un bon Etonien. » Or, à mon avis, Hook était un bon mais non pas un grand Etonien ; et c’est cette envie de vous en convaincre qui m’a poussé à venir ici cet après-midi, tout en sachant néanmoins q...

Le surpoids, l’obésité et le contrôle glycémique chez les diabétiques du centre de référence provincial de diabète (CRD), Kénitra, Maroc

Science.gov (United States)

Lotfi, Zeghari; Aboussaleh, Youssef; Sbaibi, Rachid; Achouri, Imane; Benguedour, Rachid

2017-01-01

Introduction Le diabète est définit comme un trouble de l'assimilation, de l'utilisation et du stockage des sucres apportés par l'alimentation, sa prise en charge est assurée par le suivi du surpoids et l'obésité et le contrôle glycémique régulier. L'objectif de ce travail était l'étude du surpoids, l'obésité et le contrôle glycémique chez 2227 diabétiques de différent type (type 1, 2 et gestationnel), consultants le centre de référence provincial de diabète (CRD), Kénitra-Maroc. Méthodes L'étude s'est déroulée sur une période d'une année du mois janvier au mois décembre 2015, L'évaluation du surpoids et l'obésité a été effectuée par le calcul de l'Indice de Masse Corporelle (IMC=Poids/Taille2 (Kg/m2)), elles sont définit respectivement par IMC > 25 Kg/m2, et IMC > 30 Kg/m2, le poids et la taille ont été mesurés selon les recommandations de l'organisation mondiale de santé (OMS), Le contrôle glycémique a été effectué par l'analyse sanguine de l'Hémoglobine glycosylée et de la Glycémie à jeun. Les normes sont 7% pour l'Hémoglobine glycosylée et 0,70g/l à 1,10g/l pour la Glycémie à jeun. Résultats L'intervalle d'âges des patients est compris entre 8 mois et 80 ans, avec une dominance des diabétiques provenant du milieu urbain (74%) par rapport à ceux provenant du milieu rural (26%). Le surpoids touche l'ensemble de cette population. L'IMC moyen des femmes tends vers l'obésité (IMC≈30): (29,21 Kg/m2 ± 3,1) pour le diabète gestationnel et (29,15 Kg/m2 ± 3,2) pour le diabète de type 2. Les valeurs du contrôle glycémique sont supérieures aux normes: avec 8,5% ± 2,6 > 7% pour l'hémoglobine glycosylée et 1,5 g/l ± 1,3 > 1,10g/l pour la Glycémie à jeun. La différence entre les valeurs de l'hémoglobine glycosylée entre les hommes (8,5 7% ± 2,6) et les femmes (8,1% ± 2,3) n'est pas significative (P > 0,05), même chose pour la Glycémie capillaire à jeun: pour les hommes (1,44 g/l ± 1,1) et les

Publications | Page 94 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le CRDI collabore avec les chercheurs et les établissements des pays en développement au renforcement des capacités locales par le truchement du financement, ... Le syndrome... Diamants de guerre — pour en finir. L'important accord international sur les diamants conclu cette année ne portera pas fruits s'il n'est pas ...

Tanzanie | Page 18 | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Read more about Fermented food for life (CIFSRF Phase 2). Langue English. Read more about Mobilisation au service de la préservation. Langue French. Read more about Le rôle des universités africaines dans l'innovation au service du développement inclusif. Langue French. Read more about L'emploi dans le secteur ...

Gisèle HALIMI, La Kahina

OpenAIRE

ALLOUCHE-BENAYOUN, Joëlle

2010-01-01

Est-ce un ouvrage historique ? Est-ce un roman ? Un roman historique ? Le lecteur est désemparé dès qu’il plonge dans l’ouvrage que Gisèle Halimi a consacré à la grande héroïne judéo berbère. Si l’on comprend bien l’intérêt de l’avocate féministe – par ailleurs juive et née en Tunisie – pour cette figure féminine de résistance, la gêne s’installe au fur et à mesure de la lecture, face à l’impossibilité de l’auteur de choisir un genre littéraire et de s’y tenir. Alors que le destin légendaire ...

Pronto chi parla. Cesare e le intercettazioni telefoniche

Directory of Open Access Journals (Sweden)

Paolo Caponi

2010-03-01

Full Text Available Pronto chi parla. Cesare e le intercettazioni telefoniche (Ugo Guspini, L’orecchio del regime. Le intercettazioni telefoniche al tempo del fascismo, Milano, Mursia, 1973, pp. 262 di Paolo Caponi

182 L'erotisme Dans Uwaoma Et Le Beau Monde D'ifeoma ...

African Journals Online (AJOL)

Tracie1

érotisme: Essai de définition. Il importe de mettre en ..... de son temps. Dans le monde d'aujourd'hui à la radio, à la télévision, dans les quotidiens, sur internet, dans les media sociaux tels que le facebook, le you-tube, le blackberry messenger ...

Représentation de l’espace et du temps dans le modèle situationnel construit par un lecteur

Directory of Open Access Journals (Sweden)

Yves Bestgen

2008-04-01

Full Text Available Depuis plus de vingt ans, un des défis majeurs de la psycholinguistique est de décrire la nature de la représentation mentale construite par un lecteur. Si cette question est à l’étude depuis tant d’années, c’est que, contrairement à d’autres processus comme l’accès lexical ou l’analyse syntaxique, la compréhension d’un texte est restée pendant longtemps un objet difficilement étudiable scientifiquement en raison du manque de rigueur dans sa définition et de l’absence de modèles suffisamment explicites. Tel n’est plus le cas aujourd’hui. Les chercheurs s’accordent, en effet, pourdéfinir la compréhension d’un texte comme la construction d’une représentation situationnelle qui combine les propositions extraites du texte à celles qui ont été réactivées en mémoire à long terme afin de constituer une représentation non du texte, mais de ce dont le texte parle. Parmi les multiples dimensions censées être représentées dans le modèle situationnel, l’espace et le temps sont certainement ceux qui ont retenu le plus d’attention. L’objet du présent travail est de confronter nos connaissances à propos du rôle de ceux-ci lors de la construction du modèle situationnel. Une telle analyse semble particulièrement fructueuse parce que le temps et l’espace ont été étudiés selon deux points de vues différents et pourtant complémentaires. L’étude du temps s’est focalisée principalement sur les moyens linguistiques permettant d’exprimer celui-ci dans les textes (p. ex. les adverbiaux temporels et sur leur impact lors de la compréhension. Par contre, la manière dont les informations spatiales sont présentées dans un texte a retenu bien peu l’attention au profit de la question de savoir si et comment la multidimensionnalité de l’espace peut être reconstruite par le lecteur sur la base de la linéarité d’un texte. Un des objectifs spécifiques de ce travail est de proposer, sur

Technologies de l'information et de la communication pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le deuxième volume de cette série examine l'organisation, le fonctionnement et le rôle des télécentres communautaires. Il décrit l'expérience des télécentres dans de nombreuses collectivités, généralement situées en milieu rural, et analyse les structures et les mécanismes de gestion mis en place pour les appuyer.

Chili : tous les projets | CRDI - Centre de recherches pour le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Région: Chile, Colombia, Mexico. Programme: Agriculture et sécurité alimentaire. Financement total : CA$ 5,230,900.00. Le rôle du secteur privé dans la réduction de la corruption en Amérique latine. Projet. Dans le cadre de ce projet, on étudiera les efforts déployés par le secteur privé pour améliorer la conformité aux lois ...