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Sample records for echinodermata echinoidea na

  1. Echinodermata: Echinoidea

    African Journals Online (AJOL)

    1991-05-15

    May 15, 1991 ... Table 1 List of species of sea urchin inhabiting rock substrata identified at Preslies Bay, Transkei (31°. 53'S 129°15'E). PreviOUS southernmost distributions according to Day (1974) and Clark & Courtman-Stock. (1976) are also given. Species showing a new southern record are marked with an asterisk.

  2. Origin and evolutionary plasticity of the gastric caecum in sea urchins (Echinodermata: Echinoidea

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    Rolet Gauthier

    2010-10-01

    Full Text Available Abstract Background The digestive tract of many metazoan invertebrates is characterized by the presence of caeca or diverticula that serve secretory and/or absorptive functions. With the development of various feeding habits, distinctive digestive organs may be present in certain taxa. This also holds true for sea urchins (Echinodermata: Echinoidea, in which a highly specialized gastric caecum can be found in members of a derived subgroup, the Irregularia (cake urchins, sea biscuits, sand dollars, heart urchins, and related forms. As such a specialized caecum has not been reported from "regular" sea urchin taxa, the aim of this study was to elucidate its evolutionary origin. Results Using morphological data derived from dissection, magnetic resonance imaging, and extensive literature studies, we compare the digestive tract of 168 echinoid species belonging to 51 extant families. Based on a number of characters such as topography, general morphology, mesenterial suspension, and integration into the haemal system, we homologize the gastric caecum with the more or less pronounced dilation of the anterior stomach that is observed in most "regular" sea urchin taxa. In the Irregularia, a gastric caecum can be found in all taxa except in the Laganina and Scutellina. It is also undeveloped in certain spatangoid species. Conclusions According to our findings, the sea urchin gastric caecum most likely constitutes a synapomorphy of the Euechinoidea. Its occurrence in "regular" euechinoids is linked to the presence of an additional festoon of the anterior stomach in ambulacrum III. Both structures, the additional festoon and the gastric caecum, are absent in the sister taxon to the Euechinoidea, the Cidaroida. Since the degree of specialization of the gastric caecum is most pronounced in the predominantly sediment-burrowing irregular taxa, we hypothesize that its evolution is closely linked to the development of more elaborate infaunal lifestyles. We

  3. Evolution of a novel muscle design in sea urchins (Echinodermata: Echinoidea.

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    Alexander Ziegler

    Full Text Available The sea urchin (Echinodermata: Echinoidea masticatory apparatus, or Aristotle's lantern, is a complex structure composed of numerous hard and soft components. The lantern is powered by various paired and unpaired muscle groups. We describe how one set of these muscles, the lantern protractor muscles, has evolved a specialized morphology. This morphology is characterized by the formation of adaxially-facing lobes perpendicular to the main orientation of the muscle, giving the protractor a frilled aspect in horizontal section. Histological and ultrastructural analyses show that the microstructure of frilled muscles is largely identical to that of conventional, flat muscles. Measurements of muscle dimensions in equally-sized specimens demonstrate that the frilled muscle design, in comparison to that of the flat muscle type, considerably increases muscle volume as well as the muscle's surface directed towards the interradial cavity, a compartment of the peripharyngeal coelom. Scanning electron microscopical observations reveal that the insertions of frilled and flat protractor muscles result in characteristic muscle scars on the stereom, reflecting the shapes of individual muscles. Our comparative study of 49 derived "regular" echinoid species using magnetic resonance imaging (MRI shows that frilled protractor muscles are found only in taxa belonging to the families Toxopneustidae, Echinometridae, and Strongylocentrotidae. The onset of lobe formation during ontogenesis varies between species of these three families. Because frilled protractor muscles are best observed in situ, the application of a non-invasive imaging technique was crucial for the unequivocal identification of this morphological character on a large scale. Although it is currently possible only to speculate on the functional advantages which the frilled muscle morphology might confer, our study forms the anatomical and evolutionary framework for future analyses of this unusual

  4. Evolution of a Novel Muscle Design in Sea Urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    Ziegler, Alexander; Schröder, Leif; Ogurreck, Malte; Faber, Cornelius; Stach, Thomas

    2012-01-01

    The sea urchin (Echinodermata: Echinoidea) masticatory apparatus, or Aristotle's lantern, is a complex structure composed of numerous hard and soft components. The lantern is powered by various paired and unpaired muscle groups. We describe how one set of these muscles, the lantern protractor muscles, has evolved a specialized morphology. This morphology is characterized by the formation of adaxially-facing lobes perpendicular to the main orientation of the muscle, giving the protractor a frilled aspect in horizontal section. Histological and ultrastructural analyses show that the microstructure of frilled muscles is largely identical to that of conventional, flat muscles. Measurements of muscle dimensions in equally-sized specimens demonstrate that the frilled muscle design, in comparison to that of the flat muscle type, considerably increases muscle volume as well as the muscle's surface directed towards the interradial cavity, a compartment of the peripharyngeal coelom. Scanning electron microscopical observations reveal that the insertions of frilled and flat protractor muscles result in characteristic muscle scars on the stereom, reflecting the shapes of individual muscles. Our comparative study of 49 derived “regular” echinoid species using magnetic resonance imaging (MRI) shows that frilled protractor muscles are found only in taxa belonging to the families Toxopneustidae, Echinometridae, and Strongylocentrotidae. The onset of lobe formation during ontogenesis varies between species of these three families. Because frilled protractor muscles are best observed in situ, the application of a non-invasive imaging technique was crucial for the unequivocal identification of this morphological character on a large scale. Although it is currently possible only to speculate on the functional advantages which the frilled muscle morphology might confer, our study forms the anatomical and evolutionary framework for future analyses of this unusual muscle design among

  5. Evolution of a novel muscle design in sea urchins (Echinodermata: Echinoidea).

    Science.gov (United States)

    Ziegler, Alexander; Schröder, Leif; Ogurreck, Malte; Faber, Cornelius; Stach, Thomas

    2012-01-01

    The sea urchin (Echinodermata: Echinoidea) masticatory apparatus, or Aristotle's lantern, is a complex structure composed of numerous hard and soft components. The lantern is powered by various paired and unpaired muscle groups. We describe how one set of these muscles, the lantern protractor muscles, has evolved a specialized morphology. This morphology is characterized by the formation of adaxially-facing lobes perpendicular to the main orientation of the muscle, giving the protractor a frilled aspect in horizontal section. Histological and ultrastructural analyses show that the microstructure of frilled muscles is largely identical to that of conventional, flat muscles. Measurements of muscle dimensions in equally-sized specimens demonstrate that the frilled muscle design, in comparison to that of the flat muscle type, considerably increases muscle volume as well as the muscle's surface directed towards the interradial cavity, a compartment of the peripharyngeal coelom. Scanning electron microscopical observations reveal that the insertions of frilled and flat protractor muscles result in characteristic muscle scars on the stereom, reflecting the shapes of individual muscles. Our comparative study of 49 derived "regular" echinoid species using magnetic resonance imaging (MRI) shows that frilled protractor muscles are found only in taxa belonging to the families Toxopneustidae, Echinometridae, and Strongylocentrotidae. The onset of lobe formation during ontogenesis varies between species of these three families. Because frilled protractor muscles are best observed in situ, the application of a non-invasive imaging technique was crucial for the unequivocal identification of this morphological character on a large scale. Although it is currently possible only to speculate on the functional advantages which the frilled muscle morphology might confer, our study forms the anatomical and evolutionary framework for future analyses of this unusual muscle design among sea

  6. Origin and evolutionary plasticity of the gastric caecum in sea urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    2010-01-01

    Background The digestive tract of many metazoan invertebrates is characterized by the presence of caeca or diverticula that serve secretory and/or absorptive functions. With the development of various feeding habits, distinctive digestive organs may be present in certain taxa. This also holds true for sea urchins (Echinodermata: Echinoidea), in which a highly specialized gastric caecum can be found in members of a derived subgroup, the Irregularia (cake urchins, sea biscuits, sand dollars, heart urchins, and related forms). As such a specialized caecum has not been reported from "regular" sea urchin taxa, the aim of this study was to elucidate its evolutionary origin. Results Using morphological data derived from dissection, magnetic resonance imaging, and extensive literature studies, we compare the digestive tract of 168 echinoid species belonging to 51 extant families. Based on a number of characters such as topography, general morphology, mesenterial suspension, and integration into the haemal system, we homologize the gastric caecum with the more or less pronounced dilation of the anterior stomach that is observed in most "regular" sea urchin taxa. In the Irregularia, a gastric caecum can be found in all taxa except in the Laganina and Scutellina. It is also undeveloped in certain spatangoid species. Conclusions According to our findings, the sea urchin gastric caecum most likely constitutes a synapomorphy of the Euechinoidea. Its occurrence in "regular" euechinoids is linked to the presence of an additional festoon of the anterior stomach in ambulacrum III. Both structures, the additional festoon and the gastric caecum, are absent in the sister taxon to the Euechinoidea, the Cidaroida. Since the degree of specialization of the gastric caecum is most pronounced in the predominantly sediment-burrowing irregular taxa, we hypothesize that its evolution is closely linked to the development of more elaborate infaunal lifestyles. We provide a comprehensive study of

  7. Desenvolvimento e ciclo reprodutivo da bolacha-do-mar Clypeaster subdepressus (Echinodermata: Echinoidea) de São Sebastião, SP

    OpenAIRE

    Bruno Cossermelli Vellutini

    2008-01-01

    Desenvolvimento e ciclo reprodutivo da bolacha-do-mar Clypeaster subdepressus (Echinodermata: Echinoidea) de São Sebastião, SP Resumo: Este trabalho descreve o desenvolvimento embrionário, larval e juvenil da bolacha-do-mar Clypeaster subdepressus sob microscopia de luz e eletrônica de varredura. Analisamos também o ciclo reprodutivo da espécie a partir de cortes histológicos das gônadas. A evolução morfológica da ordem Clypeasteroida (bolachas-do-mar), cerca de 55 milhões de anos atrás, este...

  8. Comparative morphology of the axial complex and interdependence of internal organ systems in sea urchins (Echinodermata: Echinoidea

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    Ziegler Alexander

    2009-06-01

    Full Text Available Abstract Background The axial complex of echinoderms (Echinodermata is composed of various primary and secondary body cavities that interact with each other. In sea urchins (Echinoidea, structural differences of the axial complex in "regular" and irregular species have been observed, but the reasons underlying these differences are not fully understood. In addition, a better knowledge of axial complex diversity could not only be useful for phylogenetic inferences, but improve also an understanding of the function of this enigmatic structure. Results We therefore analyzed numerous species of almost all sea urchin orders by magnetic resonance imaging, dissection, histology, and transmission electron microscopy and compared the results with findings from published studies spanning almost two centuries. These combined analyses demonstrate that the axial complex is present in all sea urchin orders and has remained structurally conserved for a long time, at least in the "regular" species. Within the Irregularia, a considerable morphological variation of the axial complex can be observed with gradual changes in topography, size, and internal architecture. These modifications are related to the growing size of the gastric caecum as well as to the rearrangement of the morphology of the digestive tract as a whole. Conclusion The structurally most divergent axial complex can be observed in the highly derived Atelostomata in which the reorganization of the digestive tract is most pronounced. Our findings demonstrate a structural interdependence of various internal organs, including digestive tract, mesenteries, and the axial complex.

  9. Comparative morphology of the axial complex and interdependence of internal organ systems in sea urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    Ziegler, Alexander; Faber, Cornelius; Bartolomaeus, Thomas

    2009-01-01

    Background The axial complex of echinoderms (Echinodermata) is composed of various primary and secondary body cavities that interact with each other. In sea urchins (Echinoidea), structural differences of the axial complex in "regular" and irregular species have been observed, but the reasons underlying these differences are not fully understood. In addition, a better knowledge of axial complex diversity could not only be useful for phylogenetic inferences, but improve also an understanding of the function of this enigmatic structure. Results We therefore analyzed numerous species of almost all sea urchin orders by magnetic resonance imaging, dissection, histology, and transmission electron microscopy and compared the results with findings from published studies spanning almost two centuries. These combined analyses demonstrate that the axial complex is present in all sea urchin orders and has remained structurally conserved for a long time, at least in the "regular" species. Within the Irregularia, a considerable morphological variation of the axial complex can be observed with gradual changes in topography, size, and internal architecture. These modifications are related to the growing size of the gastric caecum as well as to the rearrangement of the morphology of the digestive tract as a whole. Conclusion The structurally most divergent axial complex can be observed in the highly derived Atelostomata in which the reorganization of the digestive tract is most pronounced. Our findings demonstrate a structural interdependence of various internal organs, including digestive tract, mesenteries, and the axial complex. PMID:19508706

  10. Abundancia de Diadema antillarum (Echinodermata: Echinoidea en las costas de Venezuela

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    Nicida Noriega

    2006-09-01

    lento incremento de las poblaciones.Abundance of Diadema antillarum (Echinodermata: Echinoidea in the coasts of Venezuela. Diadema antillarum is a shallow-water sea-urchin from the tropical Atlantic whose populations almost disappeared in 1983-84 because of widespread mortalities which reached 87-100 %. In Venezuela, urchin population densities before the mortality event were comparable to those of other Caribbean regions; however, later abundancies remain unknown. The objectives of this study were to evaluate the recent densities of certain D. antillarum populations along the Venezuelan coasts and compare the densities at the Parque Nacional Mochima before and after the mortality. At each location urchin densities were determined by means of transects using 1m²-quadrats as sampling units. The highest mean densities were observed at the sites on the central coast: Ensenada de Oricao, 0.28 ind/m² (2002 and 1.05 ind/m² (2003, and Chichiriviche de la Costa, 0.84 ind/m² (2002 and 0.74 ind/m² (2003. In Mochima, the mean density before the mortality for D. antillarum oscillated between 0.28 and 4 ind/m², after the mortality event the mean density varied between 0.15 ind/m² (2000 and 0.47 ind/m² (2000. The populations of D. antillarum studied at Parque Nacional Morrocoy and Refugio de Fauna Silvestre Cuare showed highest densities at Playuela (0.43 ind/m² and Cayo Sur (0.95 ind/m² respectively, whereas other sites showed densities below 0.1 ind/m². The density registered at Playuela in 2003 is lower than that reported before the mortality event (0.58-3.64 ind/m². The density for Parque Nacional Archipiélago de Los Roques, specifically for the Arrecife de Herradura remained constant between 2002 and 2003 with values between 0.22-0.23 ind/m² respectively. To conclude, the sea urchin abundancies observed at most of the Venezuelan coastal sites that we studied were higher than those reported for other areas of the northern Caribbean, even though the values have not

  11. Mitochondrial genome evolution in Ophiuroidea, Echinoidea, and Holothuroidea: insights in phylogenetic relationships of Echinodermata.

    Science.gov (United States)

    Perseke, Marleen; Bernhard, Detlef; Fritzsch, Guido; Brümmer, Franz; Stadler, Peter F; Schlegel, Martin

    2010-07-01

    The genome architecture and amino acid sequences of six new complete mitochondrial genomes were determined from representatives of Hemichordata (1), Ophiuroidea (3), Echinoidea (1) and Holothuroidea (1) and were analysed together with previously known sequences. Phylogenetic analyses recovered three lineages within echinoderms, Crinoidea, Ophiuroidea and a group comprising Holothuroidea, Echinoidea, and Asteroidea. In contrast to previous analyses of mitochondrial genomes the increased data set recovered the classical echinoderm phylogeny of Eleutherozoa and Echinozoa in Maximum Likelihood and Bayesian analyses using hemichordate out-group representatives. However, an inconsistent ramification appeared with vertebrate out-groups and in Maximum Parsimony and Neighbour Joining reconstructions. The basal (consensus) gene orders of all three lineages could be derived from a hypothetical ancestral crinoid gene order by one single rearrangement in each lineage. The genome architecture was highly conserved in Echinoidea, whereas the highest gene order differences and large amounts of unassigned sequences (UAS) were detected in Ophiuroidea, supporting a higher evolutionary rate than in any other echinoderm lineage. The variability in gene order and UAS regions in ophiuroid genomes suggest dominating rearrangement mechanisms by duplication events. Copyright 2010 Elsevier Inc. All rights reserved.

  12. A combined morphological and molecular phylogeny for sea urchins (Echinoidea: Echinodermata).

    Science.gov (United States)

    Littlewood, D T; Smith, A B

    1995-01-30

    Phylogenetic relationships of higher taxa of echinoids have been investigated using a 163 character morphological data base and molecular sequences from large and small subunit (LSU and SSU) ribosomal RNA (rRNA) genes. The complete SSU rRNA gene has been sequenced for 21 taxa, with representatives from nine of the 14 extant orders of Echinoidea. Partial LSU sequences, representing the first 400 base pairs (b.p.) from the 5' end were also sequenced for three taxa to complement an existing data base of ten taxa. The two molecular sequences provided a total of 371 variable sites, of which 143 were phylogenetically informative (compared to 145 phylogenetically informative sites from morphological data). Morphological, LSU and SSU data have been analysed separately and together. Morphological and SSU sequence data generate topologies that are not significantly in conflict (under Templeton's test), but the strong signal pairing arbaciids with clypeasteroids in the LSU derived tree marks the LSU sequence data as anomalous for this taxon. A 'total evidence' approach derived a tree very similar in topology to that derived from morphological data. Rooted on the stem group echinoid Archaeocidaris, our total evidence tree suggested relationships of higher taxa as follows: Cidaroida (Phormosomatidae (Echinothuriidae (Diadematidae ((Spatangoida (Clypeasteroida, Cassiduloida)) ((Calycina, Arbacioida) (Stomopneustidae (Glyphocidaridae (Temnopleuridae (Echinometridae (Echinidae, Stronglyocentridae)))))))))). Phylogenetic analyses run both with and without key fossil taxa yielded slightly different topologies. It is important to include fossil taxa in a phylogenetic analysis where there are long stem-group branches or where the crown group is highly derived.

  13. Reproductive biology of Echinometra lucunter (Echinodermata: Echinoidea in a northeast Brazilian sandstone reef

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    Eduardo J.B. Lima

    2009-03-01

    demonstra diferenças sexuais na produção de gametas. Ao contrário, os machos não apresentaram nenhum padrão. Sugere-se que a reprodução da população de E. lucunter na praia de Muro Alto é contínua, compicos sazonais.

  14. Magnetic resonance imaging (MRI) has failed to distinguish between smaller gut regions and larger haemal sinuses in sea urchins (Echinodermata: Echinoidea)

    Science.gov (United States)

    Holland, Nicholas D; Ghiselin, Michael T

    2009-01-01

    A response to Ziegler A, Faber C, Mueller S, Bartolomaeus T: Systematic comparison and reconstruction of sea urchin (Echinoidea) internal anatomy: a novel approach using magnetic resonance imaging. BMC Biol 2008, 6: 33. PMID:19594924

  15. Reproductive cycle of Mellita quinquiesperforata (Leske (Echinodermata, Echinoidea in two contrasting beach environments Reprodução de Mellita quinquiesperforata (Leske (Echinodermata, Echinoidea em dois ecossistemas praiais contrastantes

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    Yara A. G. Tavares

    2006-06-01

    Full Text Available The reproductive cycle of the irregular echinoid Mellita quinquiesperforata (Leske, 1778 was studied in populations from two sand beaches with different morphodynamic conditions in Parana coast, from February 1992 through July 1994. Gametogenesis was described by histological and gonad index methods and the differences between both populations were observed in the extension of nutrient storage and spawning period. Both populations exhibited a main reproductive period during spring/summer and a nutrient storage period during autumn/winter months. The spawning period at the intermediate-dissipative beach was shorter than at the reflective beach. Meanwhile, a nutrient storage stage was more extensive in the latter. Gonad index varied between both sexes and it was influenced by population characteristics. Different strategies in allocation of resources between maintenance and reproduction effort (oocyte size confirm the high adaptive plasticity developed by this species to live in contrasting beach environments.O ciclo reprodutivo do equinóide irregular Mellita quinquiesperforata (Leske, 1778 foi estudado em populações de duas praias com diferentes condições morfodinâmicas na costa paranaense, de fevereiro de 1992 a julho de 1994. A gametogênese foi descrita pela análise histológica das gônadas e pela variação do índice gonadal. Foram encontradas diferenças com relação à extensão do período de estocagem de nutrientes e do período de liberação dos gametas nas populações. Ambas exibiram um marcado período reprodutivo na primavera e no verão e uma época de estocagem de nutrientes no outono e no inverno. Na praia intermediária-dissipativa a liberação de gametas ocorreu num período menor do que na reflectiva, porém a fase de acúmulo de reservas nutritivas foi mais extensa na primeira. O índice gonadal apresentou variações entre os sexos e foi influenciado pelas características populacionais. As diferentes estrat

  16. Reprodução de Lytechinus variegatus (Echinodermata: Echinoidea: efeito do ciclo lunar e características da população = Reproduction of Lytechinus variegatus (Echinodermata: Echinoidea: effect of lunar cycle and population characteristics

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    Alexandra Mara Cruz Lage

    2011-07-01

    Full Text Available Este estudo avaliou as características reprodutivas de uma população do ouriço do mar Lytechinus variegatus e a influência do ciclo lunar na liberação de gametas. Foram realizadas oito coletas para avaliação do índice gonadossomático (IG e dos parâmetros populacionais relacionados com a reprodução. Para avaliação do efeito da Lua na liberação de gametas foram realizadas coletas em três ciclos lunares completos. Ao todo foram coletados 295 indivíduos, sendo 156 machos e 131 fêmeas (proporção 1,19:1, porém não houve diferença significativa na proporção sexual da população. O peso dos machos foisignificativamente maior que o das fêmeas, porém não houve diferença significativa no IG, peso gonadal e diâmetro entre os sexos. Com a amplitude no diâmetro dos animais coletados (5,5-8,7 cm foram estabelecidas cinco classes de tamanho. Não houve diferençassignificativas no IG entre as classes de tamanho. Houve efeito da periodicidade lunar na liberação de gametas, com menor IG na lua nova, indicando que esta ocorre no primeiro quarto lunar e em marés de sizígia.This work evaluated the spawning of sea urchin Lytechinus variegates based on lunar cycle and population characteristics. Eight monthly collections were realized to estimate the gonadosomatic index (GI and population parameters regarding reproduction. To evaluate the effect of the lunar cycle on spawning, samples were taken for each moon phase of three lunar cycles. In the entire work 295 individuals were collected, 156 males and 131 females (1.19:1 ratio. However, there was no significant difference in the sex ratio of the population. The weight of males was significantly greater than that of females. There were no differences between males and females in gonadosomatic index (GI, gonad weight and diameter. There was aneffect of the lunar periodicity on spawning, with lower GI in new moon, indicating that spawning occurs on the first lunar quarter in spring

  17. Biologia reprodutiva de Echinometra lucunter (Echinodermata: Echinoidea na Praia da Costa, Vila Velha, Espírito Santo Reproductive biology of Echinometra lucunter (Echinodermata: Echinoidea in Praia da Costa, Vila Velha, Espírito Santo

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    Fátima L. F. Mariante

    2009-12-01

    Full Text Available Echinometra lucunter Linnaeus, 1758 is a tropical sea urchin with strong bioerosive potential. Consequently, this species has great ecological importance. The species occurs in high densities along the Brazilian coast, particularly in the south and southeast. The objective of this work was to evaluate both the effects of annual seasonality and the lunar cycle on the reproduction of E. lucunter. Individuals were sampled monthly for a period of one year and during four complete lunar cycles. The gonadosomatic index (GI was calculated to determine the annual and monthly reproductive peaks based on the lunar phase. The sex ratio (male:female was 1:1.04, without significant difference in sexual proportion. The GI was significantly higher for males than for females. The first sexual maturation occurs when carapace width reaches 23.30 mm, and 50% of the animals have gonads with 28.22 mm. The spawning peak generally occurs during the whole year from the full moon to the waning moon. However, there is an annual reproductive peak from summer to autumn.

  18. Echinothurioid phylogeny and the phylogenetic significance of Kamptosoma (Echinoidea: Echinodermata)

    Science.gov (United States)

    Mooi, Rich; Constable, Heather; Lockhart, Susanne; Pearse, John

    2004-07-01

    The Echinothurioida is an unusual group of regular sea urchins that are characterized by soft, flexible tests and in some cases, hoof-shaped spines used for locomotion across soft, deep-sea sediments. As far as is known, all species are armed with venom-bearing spines that have been known to cause serious injury in humans. There are 50 species of echinothurioids arranged in 11 extant genera. Their fossil record is very poor, being limited to two additional fossil taxa (one of which is only tentatively considered an echinothurioid), two assigned to extant taxa, and three of more dubious affinity. With very few exceptions, only disjointed plates are preserved—and those very rarely. Today, echinothurioids are found around the globe from as far north as the Arctic Circle and as far south as Antarctica, with a bathymetric distribution ranging from inshore on coral reefs to depths of almost 5000 m. The majority of species are characteristic of the deep sea, and consequently little is known about these urchins. Many are known only from type and associated material. Their fragile tests, deep benthic habitat, and rarity make it difficult to develop a complete picture of their morphology, and as we demonstrate, breakage of the test can lead to misinterpretations of plate architecture in some taxa. The sole Antarctic species, Kamptosoma asterias, is usually considered an echinothurioid, but its unusual morphology has made its position difficult to ascertain. In addition, previous genus-level phylogenies do not test the monophyly of the genera, and some studies even suggest that the echinothurioids themselves do not constitute a monophyletic group. This study focuses on finding a species level phylogeny of the echinothurioids in order to perform these tests, and to place the enigmatic Kamptosoma in a phylogenetic context that determines whether it is indeed an echinothurioid, and if so, to which clade it is most closely related. The present analysis surveys ambulacral morphology of all echinothurioids, seeking homologies that will enhance our understanding of the diversity of plate architecture in the clade. We confirm that echinothurioids are monophyletic and basal to most other extant echinoid groups, and that Kamptosoma is a relatively crownward echinothurioid, albeit a strange one. The largest genus, Araeosoma, is monophyletic, but at least one prominent genus ( Sperosoma) is not monophyletic. The resulting phylogeny also helps address questions concerning biogeographic and bathymetric distributions.

  19. Evolution of yolk protein genes in the Echinodermata.

    Science.gov (United States)

    Prowse, Thomas A A; Byrne, Maria

    2012-01-01

    Vitellogenin genes (vtg) encode large lipid transfer proteins (LLTPs) that are typically female-specific, functioning as precursors to major yolk proteins (MYPs). Within the phylum Echinodermata, however, the MYP of the Echinozoa (Echinoidea + Holothuroidea) is expressed by an unrelated transferrin-like gene that has a reproductive function in both sexes. We investigated egg proteins in the Asterozoa (Asteroidea + Ophiuroidea), a sister clade to the Echinozoa, showing that eggs of the asteroid Parvulastra exigua contain a vitellogenin protein (Vtg). vtg is expressed by P. exigua, a species with large eggs and nonfeeding larvae, and by the related asterinid Patiriella regularis which has small eggs and feeding larvae. In the Asteroidea, therefore, the reproductive function of vtg is conserved despite significant life history evolution. Like the echinozoan MYP gene, asteroid vtg is expressed in both sexes and may play a role in the development of both ovaries and testes. Phylogenetic analysis indicated that a putative Vtg from the sea urchin genome, a likely pseudogene, does not clade with asteroid Vtg. We propose the following sequence as a potential pathway for the evolution of YP genes in the Echinodermata: (1) the ancestral echinoderm produced YPs derived from Vtg, (2) bisexual vtg expression subsequently evolved in the echinoderm lineage, (3) the reproductive function of vtg was assumed by a transferrin-like gene in the ancestral echinozoan, and (4) redundant echinozoan vtg was released from stabilizing selection. © 2012 Wiley Periodicals, Inc.

  20. Correlation Between Echinoidea Size and Threat Level

    Science.gov (United States)

    Bakshi, S.; Lee, A.; Heim, N.; Payne, J.

    2017-12-01

    Echinoidea (or sea urchins), are small, spiny, globular, animals that populate the seafloors of nearly the entire planet. Echinoidea have existed on Earth since the Ordovician period, and from their archaic origin there is much to be learned about the relationship between Echinoidea body size and how it affects the survivability of the individual. The goal of this project is to determine how Echinoidea dimensions such as body volume, area, and length compare across extinct and extant species by plotting Echinoidea data in R. We will use stratigraphic data as a source to find which species of sea urchin from our data is extinct. We will then create three sets of three histograms of the size data for each type of measurement. One set will include histograms for sea urchin length, area, and volume. The other set will include histograms for extinct sea urchin length, area, and volume. The last set will include histograms for extant sea urchin length, area, and volume. Our data showed that extant sea urchins had a larger size, and extinct sea urchins were smaller. Our length data showed that the average length of all sea urchins were 54.95791 mm, the average length of extinct sea urchins were 51.0337 mm, and the average length of extant sea urchins were 66.12774 mm. There is a generally increasing trend of size over time, except for a small outlier about 350 million years ago, where echinoderm extinction selected towards larger species and biovolume was abnormally high. Our data also showed that over the past 200 million years, echinoderm extinction selectivity drove slightly smaller sea urchins towards extinction, further supporting the idea that a larger size was and still is advantageous for echinoderms.

  1. Apodida (Echinodermata: Holothuroidea) of Thailand

    DEFF Research Database (Denmark)

    Mucharin, Arom

    Systematics of Apodida (Echinodermata: Holothuroidea), with emphasis on Thai species was studied by means of adult morphology and anatomy, ossicle morphology, and phylogenetic analysis (COI). Over 300 Apodida specimens of Apodida were found in different parts of Thailand. The order comprises 25...

  2. Asteroidea, Echinoidea y Holothuroidea en fondos someros de la Bahía de Loreto, Baja California Sur, México

    Directory of Open Access Journals (Sweden)

    Oscar Holguin Quiñones

    2000-12-01

    Full Text Available Para evaluar distribución, abundancia y densidades de erizos, estrellas y pepinos de mar en la Bahía de Loreto se empleó un transecto de 50 metros, por duplicado, con un margen de observación de 2.5 m a cada lado del mismo por estación y fecha de muestreo. Se observaron mayores abundancias y densidades en la clase Echinoidea: Echinometra vanbrunti (94.1+ 52.9 ind, 0.25 ind/m², Centrostephanus coronatus (38.15+9.15 ind, 0.06 ind/m², Tripneustes depressus (28.68 + 6.86 ind, 0.039 ind/ m², Eucidaris thouarsii (10.66+3.37 ind, 0.025 ind/m² y Diadema mexicanum (11.75+4.92 ind, 0.023 ind/ m²; y para la clase Asteroidea: Phataria unifascialis, Mithrodia bradleyi y Acanthaster planci. Por el número de especies domina Asteroidea con 12, le siguen Echinoidea con 10 y Holothuroidea con 4.To evaluate echinoderm distribution, abundance and density a double 50 m transect, with a side observation range of 2.5 m was used at each of 11 stations (bimonthly samplings, Aug. 1997-Febr. 1998. In Bahía de Loreto the Phylum Echinodermata consists of 26 taxa. The greatest mean abundance by transect and mean densities in order of importance for Echinoidea were: Echinometra vanbrunti (94.1+ 52.9 ind, 0.25 ind/m², Centrostephanus coronatus (38.15. + 9.15 ind, 0.06 ind/m², Tripneustes depressus (28.68 + 6.86 ind, 0.039 ind/ m², Eucidaris thouarsii (10.66 + 3.37 ind, 0.025 ind/m² and Diadema mexicanum (11.75 + 4.92 ind, 0.023 ind/ m²; for Asteroidea were: Phataria unifascialis, Mithrodia bradleyi and Acanthaster planci. Asteroidea was the dominant class with 12 species, followed by Echinoidea with ten and Holothuroidea was represented by four species.

  3. Embryonic, Larval, and Early Juvenile Development of the Tropical Sea Urchin, Salmacis sphaeroides (Echinodermata: Echinoidea

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    M. Aminur Rahman

    2012-01-01

    Full Text Available Salmacis sphaeroides (Linnaeus, 1758 is one of the regular echinoids, occuring in the warm Indo-West Pacific, including Johor Straits, between Malaysia and Singapore. In order to investigate the developmental basis of morphological changes in embryos and larvae, we documented the ontogeny of S. sphaeroides in laboratory condition. Gametes were obtained from adult individuals by 0.5 M KCl injection into the coelomic cavity. Fertilization rate at limited sperm concentration (10−5 dilution was 96.6±1.4% and the resulting embryos were reared at 24°C. First cleavage (2-cell, 4-cell, 8-cell, 16-cell, 32-cell, and multicell (Morulla stages were achieved 01.12, 02.03, 02.28, 02.51, 03.12, and 03.32 h postfertilization. Ciliated blastulae with a mean length of 174.72±4.43 μm hatched 08.45 h after sperm entry. The gastrulae formed 16.15 h postfertilization and the archenteron elongated constantly while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larva started to feed unicellular algae in 2 d, grew continuously, and finally attained metamorphic competence in 35 d after fertilization. Metamorphosis took approximately 1 h 30 min from attachment to the complete resorption of larval tissues and the development of complete juvenile structure with adult spines, extended tubefeet and well-developed pedicellaria, the whole event of which usually took place within 1 d postsettlement. This study represents the first successful investigation on embryonic, larval, and early juvenile development of S. sphaeroides. The findings would greatly be helpful towards the understanding of ontogeny and life-history strategies, which will facilitate us to develop the breeding, seed production, and culture techniques of sea urchins in captive condition.

  4. Diadema ascensionis (Echinodermata: Echinoidea) is not restricted to Oceanic Islands: evidence from morphological data.

    Science.gov (United States)

    Gondim, A I; Dias, T L P; Christoffersen, M L

    2013-05-01

    The genus Diadema presently consists of seven species, two of which are known from the Brazilian coast: D. antillarum and D. ascensionis. The first is usually known for shallow coastal areas, while the second was apparently restricted to oceanic islands. In February 2011, a dense population of D. ascensionis was observed on the coastal reefs of Praia do Francês (Alagoas State, northeastern Brazil). Five specimens were collected and transported to the laboratory where morphological studies of the test and pedicellariae were conducted. Subsequently, visits were made to scientific collections in order to compare and confirm species identifications. Our observations confirm the presence of tridentate pedicellariae with narrow and strongly curved valves. The axial cavity in the tips of the spines is filled with dense nonreticular tissue. This taxonomic data confirms the occurrence of D. ascensionis in coastal areas. On the coastal reefs of Praia do Francês, animals were observed from the beach to the reef formations about 200 m offshore in areas with a sandy substrate and in reef cavities, usually in clear and well illuminated waters. Solitary individuals or groups of up to 15 individuals formed dense populations in the area. We stress the importance of pedicellariae for the specific identification of the Diadematidae, considering that they are quite constant and reliable at this taxonomic level. Our results demonstrate that D. ascensionis is not restricted to insular environments and that this species may be common in shallow coastal habitats.

  5. An occurence records database of Irregular Echinoids (Echinodermata: Echinoidea) in Mexico.

    Science.gov (United States)

    Martínez-Melo, Alejandra; Solís-Marín, Francisco Alonso; Buitrón-Sánchez, Blanca Estela; Laguarda-Figueras, Alfredo

    2016-01-01

    Research on echinoderms in Mexico began in the late nineteenth century. We present a dataset that includes the taxonomic and geographic information of irregular echinoids from Mexico, housed in four collections: 1) Colección Nacional de Equinodermos "Ma. Elena Caso Muñoz" from the Instituto de Ciencias del Mar y Limnología (ICML), Universidad Nacional Autónoma de México (UNAM); 2) Invertebrate Zoology Collection, Smithsonian Museum of Natural History, Washington, D.C., United States of America (USA); 3) Invertebrate Collection, Museum of Comparative Zoology, University of Harvard, Boston, Massachusetts, USA and 4) Invertebrate Zoology, Peabody Museum, Yale University, New Haven, Connecticut, USA. A total of six orders, 17 families, 35 genera and 68 species are reported, 37 distributed in the Pacific coast and 31 in the Atlantic coast, none of them was found in both coasts. The most diverse region is the Gulf of California (S=32); the most diverse order is Spatangoida with 31 species reported in mexican waters.

  6. Asthenosoma marisrubri n.sp. (Echinodermata, Echinoidea) from the Red Sea

    NARCIS (Netherlands)

    Weinberg, Steven; Ridder, de Chantal

    1998-01-01

    Indopacific echinoids of the genus Asthenosoma that have hitherto been described as A. varium actually belong to two distinct species that are geographically separated. Animals of the eastern population, extending from Sri Lanka to Hawaii and centered around the Indonesian Archipelago and the

  7. An occurence records database of Irregular Echinoids (Echinodermata: Echinoidea) in Mexico

    Science.gov (United States)

    Solís-Marín, Francisco Alonso; Buitrón-Sánchez, Blanca Estela; Laguarda-Figueras, Alfredo

    2016-01-01

    Abstract Background Research on echinoderms in Mexico began in the late nineteenth century. We present a dataset that includes the taxonomic and geographic information of irregular echinoids from Mexico, housed in four collections: 1) Colección Nacional de Equinodermos “Ma. Elena Caso Muñoz” from the Instituto de Ciencias del Mar y Limnología (ICML), Universidad Nacional Autónoma de México (UNAM); 2) Invertebrate Zoology Collection, Smithsonian Museum of Natural History, Washington, D.C., United States of America (USA); 3) Invertebrate Collection, Museum of Comparative Zoology, University of Harvard, Boston, Massachusetts, USA and 4) Invertebrate Zoology, Peabody Museum, Yale University, New Haven, Connecticut, USA. New information A total of six orders, 17 families, 35 genera and 68 species are reported, 37 distributed in the Pacific coast and 31 in the Atlantic coast, none of them was found in both coasts. The most diverse region is the Gulf of California (S=32); the most diverse order is Spatangoida with 31 species reported in mexican waters. PMID:27660526

  8. Abnormal growth patterns in the sea urchin Tripneustes cf. gratilla (l. ) under pollution (Echinodermata, Echinoidea)

    Energy Technology Data Exchange (ETDEWEB)

    Dafni, J.

    1980-10-07

    Two populations of deformed sea-urchins were found near a combined power and desalination plant in the Gulf of Eilat, Red Sea. This area is highly polluted by thermohaline and heavy metal ion effluents. More than 60% of the urchins showed irregular bulging of the aboral half of the test. The height to diameter ratio for the most affected population was 0.70, compared with 0.53 for a normal population. The deformed sea-urchins had a wider peristome aperture and larger Aristotle's lantern, and fewer interambulacral plants than normal urchins of the same diameter. Growth rate of highly deformed urchins was very low. Growth lines in the deformed urchins' plates indicate excessive growth in the meridional direction. Some possible controlling mechanisms are suggested. (4 graphs, 1 map, 11 photos, 32 references, 3 tables)

  9. Histamine is a modulator of metamorphic competence in Strongylocentrotus purpuratus (Echinodermata: Echinoidea

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    Sutherby Josh

    2012-04-01

    Full Text Available Abstract Background A metamorphic life-history is present in the majority of animal phyla. This developmental mode is particularly prominent among marine invertebrates with a bentho-planktonic life cycle, where a pelagic larval form transforms into a benthic adult. Metamorphic competence (the stage at which a larva is capable to undergo the metamorphic transformation and settlement is an important adaptation both ecologically and physiologically. The competence period maintains the larval state until suitable settlement sites are encountered, at which point the larvae settle in response to settlement cues. The mechanistic basis for metamorphosis (the morphogenetic transition from a larva to a juvenile including settlement, i.e. the molecular and cellular processes underlying metamorphosis in marine invertebrate species, is poorly understood. Histamine (HA, a neurotransmitter used for various physiological and developmental functions among animals, has a critical role in sea urchin fertilization and in the induction of metamorphosis. Here we test the premise that HA functions as a developmental modulator of metamorphic competence in the sea urchin Strongylocentrotus purpuratus. Results Our results provide strong evidence that HA leads to the acquisition of metamorphic competence in S. purpuratus larvae. Pharmacological analysis of several HA receptor antagonists and an inhibitor of HA synthesis indicates a function of HA in metamorphic competence as well as programmed cell death (PCD during arm retraction. Furthermore we identified an extensive network of histaminergic neurons in pre-metamorphic and metamorphically competent larvae. Analysis of this network throughout larval development indicates that the maturation of specific neuronal clusters correlates with the acquisition of metamorphic competence. Moreover, histamine receptor antagonist treatment leads to the induction of caspase mediated apoptosis in competent larvae. Conclusions We conclude that HA is a modulator of metamorphic competence in S. purpuratus development and hypothesize that HA may have played an important role in the evolution of settlement strategies in echinoids. Our findings provide novel insights into the evolution of HA signalling and its function in one of the most important and widespread life history transitions in the animal kingdom - metamorphosis.

  10. Do genes lie? Mitochondrial capture masks the Red Sea collector urchin's true identity (Echinodermata: Echinoidea: Tripneustes).

    Science.gov (United States)

    Bronstein, Omri; Kroh, Andreas; Haring, Elisabeth

    2016-11-01

    Novel COI and bindin sequences of the Red Sea collector echinoid Tripneustes gratilla elatensis are used to show that (1) discordance between mitochondrial and nuclear loci exists in this echinoid genus, (2) Tripneustes gratilla as currently defined possibly comprises a complex of cryptic species, and (3) Red Sea Tripneustes form a genetically distinct clade in the bindin tree, which diverged from other Tripneustes clades at least 2-4million years ago. Morphological reassessment of T. gratilla elatensis shows perfect congruence between identification based on skeletal features and genetic data based on a nuclear marker sequence. Hence the Red Sea Tripneustes subspecies established by Dafni in 1983 is a distinct biological unit. All T. g. elatensis samples analyzed are highly similar to or share mtDNA haplotypes with Philippine T. g. gratilla, as do representatives from other edge-of-range occurrences. This lack of genetic structure in Indo-Pacific Tripneustes is interpreted as a result of wide-spread mitochondrial introgression. New fossil specimens from the Red Sea area confirm the sympatric occurrence of T. g. elatensis and T. g. gratilla in the northern Red Sea during Late Pleistocene, identifying a possible timing for the introgression. In addition, present-day distribution shows a contact zone in the Southern Red Sea (in the Dahlak Archipelago). T. g. elatensis, is yet another example of a Red Sea taxon historically identified as conspecific with its Indo-Pacific relatives, but which turned out to be a morphologically and genetically distinct endemic taxon, suggesting that the level of endemism in the Red Sea may still be underestimated. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Holistic morphometric analysis of growth of the sand dollar Echinarachnius parma (Echinodermata:Echinoidea:Clypeasteroida).

    Science.gov (United States)

    Zachos, Louis G

    2015-12-02

    Holistic morphometrics is a term implying complete shape characterization of all of the structural parts of an organism. The skeleton of an echinoid is comprised of hundreds of individual plates arranged in a closed 3-dimensional mosaic forming the test. GIS software and techniques were used to generate topologically correct digital models of an ontogenetic series of specimens of the sand dollar echinoid Echinarachnius parma. Plate growth can be considered in proportion to overall skeleton growth, resulting in a linear model of relative growth. Alternatively, separate logistic equations can be fit to the ontogenetic series of homologous plate areas using nonlinear least squares regression to result in a model for instantaneous growth. The linear and logistic parameters of the models describe the allometric growth of plates from different viewpoints. Growth is shown to fall into characteristic patterns defining distinct plate growth domains associated with development of the imago (larval) skeleton just prior to metamorphosis, early growth associated with expansion of the corona and fold-over (forming the flattened body form), juvenile growth and formation of petals, and adult growth. Functions of growth, plate translocation, plate juxtaposition between aboral and oral surfaces, and relationships with internal buttressing are quantified. Results offer explanations for general skeletal symmetry, distinction between ambulacral and interambulacral growth, the relationship of growth to internal buttressing, existence of a distinct petalodium, and anterior-posterior asymmetry during development. The parametric values of growth functions derived from the results are a basis for computational modeling of growth and development in sand dollars.

  12. Does Encope emarginata (Echinodermata: Echinoidea) affect spatial variation patterns of estuarine subtidal meiofauna and microphytobenthos?

    Science.gov (United States)

    Brustolin, Marco C.; Thomas, Micheli C.; Mafra, Luiz L.; Lana, Paulo da Cunha

    2014-08-01

    Foraging macrofauna, such as the sand dollar Encope emarginata, can modify sediment properties and affect spatial distribution patterns of microphytobenthos and meiobenthos at different spatial scales. We adopted a spatial hierarchical approach composed of five spatial levels (km, 100 s m, 10 s m, 1 s m and cm) to describe variation patterns of microphytobenthos, meiobenthos and sediment variables in shallow subtidal regions in the subtropical Paranaguá Bay (Southern Brazil) with live E. emarginata (LE), dead E. emarginata (only skeletons - (DE), and no E. emarginata (WE). The overall structure of microphytobenthos and meiofauna was always less variable at WE and much of variation at the scale of 100 s m was related to variability within LE and DE, due to foraging activities or to the presence of shell hashes. Likewise, increased variability in chlorophyll-a and phaeopigment contents was observed among locations within LE, although textural parameters of sediment varied mainly at smaller scales. Variations within LE were related to changes on the amount and quality of food as a function of sediment heterogeneity induced by the foraging behavior of sand dollars. We provide strong evidence that top-down effects related to the occurrence of E. emarginata act in synergy with bottom-up structuring related to hydrodynamic processes in determining overall benthic spatial variability. Conversely, species richness is mainly influenced by environmental heterogeneity at small spatial scales (centimeters to meters), which creates a mosaic of microhabitats.

  13. Fossil echinoid (Echinoidea, Echinodermata diversity of the Early Cretaceous (Hauterivian in the Paris Basin (France

    Directory of Open Access Journals (Sweden)

    Sophie Benetti

    2013-08-01

    Full Text Available This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires à Spatangues Formation (CSF that crops out in the southeast of the Paris Basin (France, and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous. Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by locality names and geographic coordinates with decimal numbers of fossil echinoids both collated from the literature published over a century and a half, and completed by data from collection specimens. The dataset also gives information on taxonomy (from species to order and higher taxonomic levels, which has been checked for reliability and consistency. It compiles a total of 628 georeferenced occurrence data of 26 echinoid species represented by 22 genera, 14 families, and 9 orders.

  14. Fossil echinoid (Echinoidea, Echinodermata) diversity of the Early Cretaceous (Hauterivian) in the Paris Basin (France)

    OpenAIRE

    Benetti,Sophie; Saucède,Thomas; David,Bruno

    2013-01-01

    Abstract This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires ? Spatangues Formation (CSF) that crops out in the southeast of the Paris Basin (France), and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous). Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by local...

  15. Testing the molecular clock: molecular and paleontological estimates of divergence times in the Echinoidea (Echinodermata).

    Science.gov (United States)

    Smith, Andrew B; Pisani, Davide; Mackenzie-Dodds, Jacqueline A; Stockley, Bruce; Webster, Bonnie L; Littlewood, D Timothy J

    2006-10-01

    The phylogenetic relationships of 46 echinoids, with representatives from 13 of the 14 ordinal-level clades and about 70% of extant families commonly recognized, have been established from 3 genes (3,226 alignable bases) and 119 morphological characters. Morphological and molecular estimates are similar enough to be considered suboptimal estimates of one another, and the combined data provide a tree that, when calibrated against the fossil record, provides paleontological estimates of divergence times and completeness of their fossil record. The order of branching on the cladogram largely agrees with the stratigraphic order of first occurrences and implies that their fossil record is more than 85% complete at family level and at a resolution of 5-Myr time intervals. Molecular estimates of divergence times derived from applying both molecular clock and relaxed molecular clock models are concordant with estimates based on the fossil record in up to 70% of cases, with most concordant results obtained using Sanderson's semiparametric penalized likelihood method and a logarithmic-penalty function. There are 3 regions of the tree where molecular and fossil estimates of divergence time consistently disagree. Comparison with results obtained when molecular divergence dates are estimated from the combined (morphology + gene) tree suggests that errors in phylogenetic reconstruction explain only one of these. In another region the error most likely lies with the paleontological estimates because taxa in this region are demonstrated to have a very poor fossil record. In the third case, morphological and paleontological evidence is much stronger, and the topology for this part of the molecular tree differs from that derived from the combined data. Here the cause of the mismatch is unclear but could be methodological, arising from marked inequality of molecular rates. Overall, the level of agreement reached between these different data and methodological approaches leads us to believe that careful application of likelihood and Bayesian methods to molecular data provides realistic divergence time estimates in the majority of cases (almost 80% in this specific example), thus providing a remarkably well-calibrated phylogeny of a character-rich clade of ubiquitous marine benthic invertebrates.

  16. Fossil echinoid (Echinoidea, Echinodermata) diversity of the Early Cretaceous (Hauterivian) in the Paris Basin (France).

    Science.gov (United States)

    Benetti, Sophie; Saucède, Thomas; David, Bruno

    2013-01-01

    This dataset inventories occurrence records of fossil echinoid specimens collected in the Calcaires à Spatangues Formation (CSF) that crops out in the southeast of the Paris Basin (France), and is dated from the Acanthodiscus radiatus chronozone (ca. 132 Ma, early Hauterivian, Early Cretaceous). Fossil richness and abundance of the CSF has attracted the attention of palaeontologists since the middle of the nineteenth century. This dataset compiles occurrence data (referenced by locality names and geographic coordinates with decimal numbers) of fossil echinoids both collated from the literature published over a century and a half, and completed by data from collection specimens. The dataset also gives information on taxonomy (from species to order and higher taxonomic levels), which has been checked for reliability and consistency. It compiles a total of 628 georeferenced occurrence data of 26 echinoid species represented by 22 genera, 14 families, and 9 orders.

  17. Leptosalenia botanzi sp. nov. (Echinodermata: Echinoidea del Albiense de la cuenca Vasco-Cantábrica.

    Directory of Open Access Journals (Sweden)

    Enric Forner, Txema Moreno.

    2016-01-01

    Esta es la tercera especie de Leptosalenia registrada en la cuenca Vasco-Cantabrica; las otras dos son L. prestensis (Desor, 1856 y L. barredai Forner, 2014. El listado para toda la península ibérica se completa con L. grasi (Cotteau, 1861. L. botanzi es la segunda especie de este género que se describe, recientemente, en el Albiense de la península ibérica. La otra especie L. barredai descrita en la cuenca del Maestrat ha sido encontrada también en la cuenca Vasco-Cantábrica, confirmando la fácil comunicación entre las dos cuencas.

  18. Assessment of microplastic toxicity to embryonic development of the sea urchin Lytechinus variegatus (Echinodermata: Echinoidea).

    Science.gov (United States)

    Nobre, C R; Santana, M F M; Maluf, A; Cortez, F S; Cesar, A; Pereira, C D S; Turra, A

    2015-03-15

    Apart from the physiological impacts on marine organisms caused by ingesting microplastics, the toxicity caused by substances leaching from these particles into the environment requires investigation. To understand this potential risk, we evaluated the toxicity of virgin (raw) and beach-stranded plastic pellets to the development of embryos of Lytechinus variegatus, simulating transfers of chemical compounds to interstitial water and water column by assays of pellet-water interface and elutriate, respectively. Both assays showed that virgin pellets had toxic effects, increasing anomalous embryonic development by 58.1% and 66.5%, respectively. The toxicity of stranded pellets was lower than virgin pellets, and was observed only for pellet-water interface assay. These results show that (i) plastic pellets act as a vector of pollutants, especially for plastic additives found on virgin particles; and that (ii) the toxicity of leached chemicals from pellets depends on the exposure pathway and on the environmental compartment in which pellets accumulate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Variación espacio-temporal de Scleractinia, Gorgonacea, Gastropoda, Bivalvia, Cephalopoda, Asteroidea, Echinoidea y Holothuroidea, de fondos someros de la isla San José, Golfo de California

    Directory of Open Access Journals (Sweden)

    Oscar Efraín Holguin Quiñones

    2008-09-01

    Full Text Available Se realizaron seis expediciones a la isla San José, Golfo de California entre los años 1999 y 2000 en donde se llevaron a cabo las observaciones y muestreos. Con base en los muestreos se determinó el componente específico de tres filos de macroinvertebrados bentónicos en nueve localidades: Cnidaria (Scleractinia y Gorgonacea, Mollusca (Gastropoda, Bivalvia y Cephalopoda, y Echinodermata (Echinoidea, Asteroidea y Holothuroidea. La abundancia del macrobentos conspicuo se estimó visualmente mediante buceo libre a una profundidad entre 2 y 6 m a lo largo de dos transectos en banda paralelos a la línea de costa. Se determinó un total de 38 táxones de los tres grupos. Las especies más abundantes son Tripneustes depressus (44,9%, Echinometra vanbruntii (18,3, Phataria unifascialis (8,9%, Centrostephanus coronatus (8,0%, Diadema mexicanum (5% y Eucidaris thouarsii (3,6%. No se encontraron diferencias significativas en la diversidad (H’, equidad (J y riqueza de especies (S entre los meses y localidades. El análisis de similitud identificó a dos grupos de las localidades del litoral oriental y occidental.Space-time variation of Scleractinia, Gorgonacea, Gastropoda, Bivalvia, Cephalopoda, Asteroidea, Echinoidea and Holothuroidea, from shallow bottom in San Jose Island, Gulf of California. Between the years 1999 and 2000, six expeditions were made to Isla San José, in the Gulf of California. Observations and samples were taken of benthic macroinvertebrates in nine locations. Based on the samples, the specific components of three phyla were determined: Cnidaria (Scleractinia and Gorgonacea, Mollusca (Gastropoda, Bivalvia and Cephalopoda, and Echinodermata (Echinoidea and Holothuroidea. The abundance of conspicuous benthic macroinvertebrates was visually estimated through free dives at a depth of between two and six meters along two transects parallel to the coast. A total of 38 taxa in three groups were determined. The most abundant species

  20. Larval myogenesis in Echinodermata: conserved features and morphological diversity between class-specific larval forms of Echinoidae, Asteroidea, and Holothuroidea.

    Science.gov (United States)

    Dyachuk, Vyacheslav; Odintsova, Nelly

    2013-01-01

    The myogenesis of class-specific larval forms of three classes belonging to the phylum Echinodermata (Echinoidae, Asteroidea, and Holothuroidea) was investigated via gross-anatomy and comparative morphology of larval muscles. Using staining with phalloidin and antibodies against the muscle proteins, with subsequent CLSM and 3D imaging, we have examined myogenesis in the larvae from the gastrula stage to pre-metamorphosis larval stages. We have shown that temporal and spatial expression of muscle proteins is similar in echinoidea and asteroidea larvae but differs in holothuroidea larvae at early developmental stages. New insights regarding the protein composition of maturing muscular fibrils during development in echinoderm larvae were detected. The first differentiating muscle structures in all tested classes have been found to be circular esophageal muscles that are associated with larval feeding. During early differentiation of echinoderm larval muscle cells, we observed that the expression patterns of the muscle proteins were not uniform but with a characteristic diffuse distribution, which is typical for smooth muscle. An unusual pattern of expression of the muscle proteins was detected in larval sphincters: the thick muscle proteins were first expressed during the early developmental stages, whereas F-actin appeared at later stages. In addition, paired star-shaped muscles were revealed in the mature Echinoidae plutei, but were absent in the Asteroidea, and Holothuroidea larvae. All tested species of Echinodermata exhibited both conserved features of muscle morphology during development indicating a common life history strategy and a planktonic habitat, and also an extensive morphological diversity representing specific anatomical adaptations during development. © 2013 Wiley Periodicals, Inc.

  1. Studying the Body Sizes of Echinoidea during the Mesozoic Era

    Science.gov (United States)

    Tenorio, E.; Gupta, A.; Panneerselvam, S.; Heim, N. A.; Payne, J.

    2013-12-01

    Body size is an important trait that is affected by many factors such as temperature and space, more specifically the distance from the equator. We are studying whether Bergmann's rule or Cope's rule is dominant in the class Echinoidea during the Mesozoic Era. Bergmann's rule states that temperature and body size have an inverse correlation: as temperature decreases, body size increases. Bergmann's rule also states that as the distance from the equator increases, body size increases. The other principle we are studying, Cope's rule, dictates that the overall body size of an organism increases over time. Because CO2 is a greenhouse gas, we used rCO2 as a proxy for paleotemperature. The result from plotting body size against time was that as time progressed, body size tended to increase, supporting Cope's rule. By conducting correlation tests, we found that rCO2 and maximum area had a small, but significant, negative correlation, proving Bergmann's rule, but showing that there are other significant factors affecting the body sizes of Echinoids during this time period. After plotting the sizes against space, we found that these two factors had an inverse correlation during the Jurassic and Cretaceous periods, indicating that as distance from equator increases, size decreases. Cope's rule was supported since the overall trend is an increase in Echinoidea body size; in terms of space, however, Bergmann's rule did not apply to the class Echinoidea because the overall body size of the echinoderm decreased as the distance from equator increased. With this unexpected result, we concluded that there must have been another driving force other than temperature that influenced echinoids during the Mesozoic Era.

  2. Two new species of poecilostomatoid copepods symbiotic on the venomous echinoid Toxopneustes pileolus (Lamarck) (Echinodermata) from Vietnam.

    Science.gov (United States)

    Venmathi Maran, Balu Alagar; Kim, Il-Hoi; Bratova, Olga A; Ivanenko, Viatcheslav N

    2017-02-01

    Two new coexisting species of crustacean copepods (Poecilostomatoida) belonging to the echinoid-specific genera Mecomerinx Humes, 1977 (Pseudanthessiidae) and Clavisodalis Humes, 1970 (Taeniacanthidae) found associated with the venomous flower urchin Toxopneustes pileolus (Lamarck) (Echinodermata: Echinoidea: Toxopneustidae) in the South China Sea (Vietnam) are described. The diagnostic features of Mecomerinx ohtsukai n. sp. are: (i) three setae and one aesthetasc on the first segment of antennules; (ii) relatively long caudal ramus; (iii) elongated terminal segment of the antenna; and (iv) two claws on the terminal segment of antenna slightly unequal in length. The taeniacanthid copepod Clavisodalis toxopneusti n. sp. is distinguished from all seven known congeners by having two-segmented endopod of the legs 2-4 and four setae on the distal endopodal segment of the leg 1. This is the first report on copepods associated with echinoids of the genus Toxopneustes Agassiz and the first finding of Mecomerinx as well as taeniacanthid copepods in the South China Sea associated with echinoids.

  3. Echinodermata

    African Journals Online (AJOL)

    TOSHIBA

    2015-06-23

    Jun 23, 2015 ... Images were processed using OLYMPUS FLOVIEW 1.7b viewer and Adobe. Photoshop CS3. Preabsorption control was done by substituting the primary antibody with PBS or preabsorbed antibody. Working dilutions of GFSKLYFamide antibody (1: 1000 in PBS) were preabsorbed overnight at 4°C with 100 ...

  4. A comparative study of vitellogenesis in Echinodermata: Lessons from the sea star.

    Science.gov (United States)

    Alqaisi, Khalid M; Lamare, Miles D; Grattan, Dave R; Damsteegt, Erin L; Schneider, Wolfgang J; Lokman, P Mark

    2016-08-01

    The provision of yolk precursor proteins to the oviparous egg is crucial for normal embryo development. In Echinodermata, a transferrin-like yolk component termed major yolk protein (MYP) is a major precursor protein in Echinoidea and Holothuroidea. In contrast, in Asteroidea a single vitellogenin (Vtg) was recently identified, but its role as primary yolk protein remains unclear. To resolve the apparent MYP-Vtg dichotomy in sea stars and to understand the dynamics of candidate yolk protein gene expression during the reproductive cycle, we investigated the molecular structures of sea star Vtg and MYP and quantified their transcript levels during oogenesis. By combining protein sequencing of the predominant proteins in ovulated eggs of Patiriella regularis with ovarian transcriptome sequencing and molecular cloning, we characterized two cDNAs encoding two bona fide Vtgs (PrVtg1 and PrVtg2) and a partial cDNA encoding MYP (PrMYP). PrMYP mRNA was found in low abundance in growing oocytes, possibly as maternal transcripts for translation after ovulation. In contrast, PrVtg transcripts, whose levels varied during the reproductive cycle, were not found in developing oocytes - rather, they were detected in ovarian follicle cells and pyloric caeca, indicating an extra-oocytic origin. Vtg accumulating in oocytes was stored in the form of cleaved products, which constituted the most abundant yolk polypeptides in ovulated sea star eggs; their levels decreased during early embryonic and larval development. Together, these traits are the hallmarks of a classical yolk protein - and hence, we contend that Vtg, and not MYP, is the main yolk protein in asteroids. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Macrofaunal involvement in the sublittoral decay of kelp debris: The sea urchin Psammechinus miliaris (Gmelin) (Echinodermata: Echinoidea)

    Science.gov (United States)

    Bedford, A. P.; Moore, P. G.

    1985-01-01

    Psammechinus miliaris occurs in the Clyde Sea area in large numbers (diet of rotting weed but not on fresh weed. Large seasonal variation existed, however, with fast growth occurring in June-August and little, or no, growth in December-February, irrespective of diet. Starved controls did not grow. Correcting for seasonality, rotting kelp still promoted faster growth of young urchins than did fresh weed. Larger (older) individuals showed no difference. Urchins fed fresh weed had significantly longer gut retention times. Protein absorption efficiency was higher on fresh than rotting weed, varying with weed protein content and size of urchin. Very young individuals can only digest high protein weed efficiently, eg. material derived from near the frond meristem. Organic carbon content of rotting weed was significantly lower than fresh weed. Carbon absorption efficiencies were significantly higher on fresh weed which related to organic carbon content. Standard-sized urchins fed rotting weed produced larger dry weights of faeces per day, reflecting increased ingestion rate. In closed-system choice experiments urchins preferred rotting weed kinetically. Size-frequency analysis of field populations suggested that weed beds are principally colonized by larval settlement from the plankton. Mature Psammechinus have evolved different 'strategies' for exploiting fresh and rotting weed. Fresh weed is relatively difficult to digest and long gut retention times allow high protein absorption efficiencies to be attained. Rotting weed has microbial protein in quantities and a lower organic carbon fraction. Some bacterial protein is seemingly unavailable though and lower protein absorption efficiencies result. Thus gut retention time is shortened and more food passed through the gut. Growth remains equivalent. Substratum digestion is of paramount importance for Psammechinus feeding on either fresh or rotting weed, cf. the 'classical' microbe-stripping detritivore of Fenchel.

  6. Evolutionary history of larval skeletal morphology in sea urchin Echinometridae (Echinoidea: Echinodermata) as deduced from mitochondrial DNA molecular phylogeny.

    Science.gov (United States)

    Kinjo, Sonoko; Shirayama, Yoshihisa; Wada, Hiroshi

    2008-01-01

    The larval skeletons of sea urchins show considerable morphological diversity, even between closely related species, although the evolutionary history and functional significance of this diversity are poorly understood. To infer the evolutionary history of the skeletal morphology, we focused on echinometrid species for which the morphological variation in larval skeletons had been investigated qualitatively and quantitatively. We reconstructed the phylogenetic relationships among 14 echinometrid species based on mitochondrial ND1 and ND2 genes and mapped the morphological characters onto the resultant trees. The monophyly of each genus in the Echinometridae was well supported by our results, as was the close affinity between Colobocentrotus, Heterocentrotus, and Echinometra. The mapping of the morphological characters of the larval skeletons indicated that the length, direction, and density of spines on the postoral rods was well conserved in each group of Echinometridae and that the abundance of spines and the size and shape of the body skeleton changed relatively frequently and hence were less conserved. In Echinometrid species, morphological variation in relatively unconserved features tends to be associated with latitudinal distributions, rather than phylogenetic relationships, indicating that the morphological diversity of larval skeletons could have been caused by adaptation to the habitat environment. Some morphological differences, however, seem to be nonfunctional and generated by the constraints on larval skeletogenesis. Thus, echinometrid species can be a good model with which to study the evolutionary history from both ecological and developmental standpoints.

  7. Bathyal sea urchins of the Bahamas, with notes on covering behavior in deep sea echinoids (Echinodermata: Echinoidea)

    Science.gov (United States)

    Pawson, David L.; Pawson, Doris J.

    2013-08-01

    In a survey of the bathyal echinoderms of the Bahama Islands region using manned submersibles, approximately 200 species of echinoderms were encountered and documented; 33 species were echinoids, most of them widespread in the general Caribbean area. Three species were found to exhibit covering behavior, the piling of debris on the upper surface of the body. Active covering is common in at least 20 species of shallow-water echinoids, but it has been reliably documented previously only once in deep-sea habitats. Images of covered deep-sea species, and other species of related interest, are provided. Some of the reasons adduced in the past for covering in shallow-water species, such as reduction of incident light intensity, physical camouflage, ballast in turbulent water, protection from desiccation, presumably do not apply in bathyal species. The main reasons for covering in deep, dark, environments are as yet unknown. Some covering behavior in the deep sea may be related to protection of the genital pores, ocular plates, or madreporite. Covering in some deep-sea species may also be merely a tactile reflex action, as some authors have suggested for shallow-water species.

  8. Ectosymbiosis associated with cidaroids (Echinodermata: Echinoidea) promotes benthic colonization of the seafloor in the Larsen Embayments, Western Antarctica

    Science.gov (United States)

    Hardy, C.; David, B.; Rigaud, T.; De Ridder, C.; Saucède, T.

    2011-03-01

    Ice-shelf collapses in the Larsen A and B embayments along the Weddell side of the Antarctic Peninsula resulted in new open-water areas that are likely reorganizing benthic communities. It is a natural laboratory to assess colonization of the sea bottom under new conditions. We tested the hypothesis that the epibionts associated to cidaroid echinoids could promote or enhance the colonization of hard surfaces. In fact, being vagile, cidaroids might improve dispersal capabilities of the sessile animals that are attached to their spines, e.g., promoting the colonization of areas where the fauna has been eradicated by iceberg scouring. If this hypothesis is correct, pioneer sessile species present locally on stones might have affinities with ectosymbionts on cidaroids, and the sessile fauna present both on cidaroids and stones should be more similar in the Larsen embayments than in undisturbed areas. We therefore compared sessile species living on cidaroids with those living on stones in three areas: Larsen A and B embayments and two undisturbed and geographically different areas, Atka Bay and Elephant Island. Overall, richness, evaluated as 'morphotypes' richness, was lower in the Larsen area than in other areas, but levels of species diversity were similar among the three zones. The estimate of similarity between assemblages (using the C22 index of Chao et al., 2008) also suggests that cidaroid epibionts are either species-specific or specific to cidaroids, while the composition of sessile fauna on stones is more variable and probably dependent on local factors. In the two undisturbed areas, sessile fauna are highly different between stones and cidaroids. This contrasts with the Larsen embayments where cidaroids share more than 80% of epibionts with the surrounding stones. These results suggest that ectosymbioses linked to cidaroids strongly contribute to benthic colonization of the seafloor in the Larsen enbayments. With time, secondary successions are expected to occur, increasing the difference between epibiotic communities on cidaroids and those on stones, and lead to the situations observed in unperturbed sites.

  9. Nuevos datos sobre la distribución de Centrostephanus longispinus (Echinodermata: Echinoidea en las costas españolas

    Directory of Open Access Journals (Sweden)

    Moreno, Diego

    1996-12-01

    Full Text Available Some new records of the rare sea urchin Centrostephanus longispinus are given in the Spanish coasts, all of them widespread along the Balearic Islands, Levante, Alboran Sea and Atlantic side of the Strait of Gibraltar. From these data, conclusions about its range of distribution in Spanish water, habitat and its optimal range of temperature are provided.Se aportan nuevas citas del raro erizo de mar Centrostephanus longispinus en las costas españolas, repartidas por el archipiélago balear, Levante español, mar de Alborán y vertiente atlántica del estrecho de Gibraltar. Con los datos obtenidos se obtienen una serie de conclusiones sobre la distribución de la especie en aguas españolas, su hábitat y el intervalo de temperaturas que tolera.

  10. Diadema ascensionisMortensen, 1909 (Echinodermata: Echinoidea is not restricted to Oceanic Islands: evidence from morphological data

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    AI Gondim

    Full Text Available The genus Diadema presently consists of seven species, two of which are known from the Brazilian coast: D. antillarum and D. ascensionis. The first is usually known for shallow coastal areas, while the second was apparently restricted to oceanic islands. In February 2011, a dense population of D. ascensionis was observed on the coastal reefs of Praia do Francês (Alagoas State, northeastern Brazil. Five specimens were collected and transported to the laboratory where morphological studies of the test and pedicellariae were conducted. Subsequently, visits were made to scientific collections in order to compare and confirm species identifications. Our observations confirm the presence of tridentate pedicellariae with narrow and strongly curved valves. The axial cavity in the tips of the spines is filled with dense nonreticular tissue. This taxonomic data confirms the occurrence of D. ascensionis in coastal areas. On the coastal reefs of Praia do Francês, animals were observed from the beach to the reef formations about 200 m offshore in areas with a sandy substrate and in reef cavities, usually in clear and well illuminated waters. Solitary individuals or groups of up to 15 individuals formed dense populations in the area. We stress the importance of pedicellariae for the specific identification of the Diadematidae, considering that they are quite constant and reliable at this taxonomic level. Our results demonstrate that D. ascensionis is not restricted to insular environments and that this species may be common in shallow coastal habitats.

  11. Complete mitochondrial genome of the sea cucumber Apostichopus japonicus (Echinodermata: Holothuroidea): the first representative from the subclass Aspidochirotacea with the echinoderm ground pattern.

    Science.gov (United States)

    Shen, Xin; Tian, Mei; Liu, Zhihong; Cheng, Hanliang; Tan, Jie; Meng, Xueping; Ren, Jianfeng

    2009-06-15

    Complete mitochondrial genome plays an important role in the accurate revelation of phylogenetic relationships among metazoans. Here we present the complete mitochondrial genome sequence from a sea cucumber Apostichopus japonicus (Echinodermata: Holothuroidea), which is the first representative from the subclass Aspidochirotacea. The mitochondrial genome of A. japonicus is 16,096 bp in length. The heavy strand consists of 31.8% A, 20.2% C, 17.9% G, and 30.1% T bases (AT skew=0.027; GC skew=0.062). It contains thirteen protein-coding genes (PCGs), twenty-two transfer RNA genes, and two ribosomal RNA genes. There are a total of 3793 codons in all thirteen mitochondrial PCGs, excluding incomplete termination codons. The most frequently used amino acid is Leu (15.77%), followed by Ser (9.73%), Met (8.62%), Phe (7.94%), and Ala (7.28%). Intergenetic regions in the mitochondrial genome of A. japonicus are 839 bp in total, with three relatively large regions of Unassigned Sequences (UAS) greater than 100 bp. The gene order of A. japonicus is identical to that observed in the five studied sea urchins, which confirms that the gene order shared by the two classes (Holothuroidea and Echinoidea) is a ground pattern of echinoderm mitochondrial genomes. Bayesian tree based on the cob gene supports the following relationship: (outgroup, (Crinoids, (Asteroids, Ophiuroids, (Echinoids, Holothuroids)))).

  12. Sclerites in different tissues of Mediterranean Echinodermata.

    Science.gov (United States)

    Ocaña Martín, Amelia; Tierno de Figueroa, J Manuel; Palomino-Morales, Rogelio J

    2006-06-01

    The presence of sclerites in different mesodermal tissues was studied in thirteen species of Mediterranean echinoderms representing the five living classes. In the species of Asteroidea and Crinoidea examined, sclerites were present only in specific tissues. In the species of Ophiuroidea and, especially, Echinoidea and Holothuroidea examined, sclerites were present in almost every tissue, but with considerable variation among species and tissues. Data on sclerite shape, size, and relative abundance (measured as tissue abundance) are presented. The data support the possible functional role of sclerites as reinforcing structures, as well as their possible use as taxonomic characters. Finally, the need of more studies to elucidate the ontogenetic and phylogenetic implications of sclerites is discussed.

  13. [Echinoderms (Echinodermata) of the Mexican Caribbean].

    Science.gov (United States)

    Laguarda-Figueras, Alfredo; Solis-Marín, Francisco A; Durán-González, Alicia; Ahearn, Cynthia Gust; Buitrón Sánchez, Blanca Estela; Torres-Vega, Juan

    2005-12-01

    A systematic list of the echinoderms of the Mexican Caribbean based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. This list reveals an important echinoderm biodiversity in the Mexican Caribbean, where five of the six echinoderm classes are represented. A total of 178 echinoderm species is recorded, distributed in 113 genera, 51 families and 22 orders. 30 new records for the Mexican Caribbean are presents: Crínoidea (three), Asteroidea (two), Ophiuroidea (eleven), Echinoidea (one), Holothuroidea (thirteen).

  14. INVENTARISASI JENIS ARTHROPODA DAN ECHINODERMATA DI ZONA PASANG SURUT TIPE SUBSTRAT BERBATU PANTAI GATRA KABUPATEN MALANG

    Directory of Open Access Journals (Sweden)

    Arindra Trisna Widiansyah

    2016-07-01

    Pantai Gatra merupakan salah satu ekowisata pantai di Kabupaten Malang yang memiliki zona pasang surut dengan substrat dominan batu. Substrat berbatu merupakan daerah yang paling padat makroorganismenya. Arthropoda dan Echinodermata mempunyai peranan penting dari segi sumber makanan maupun ekologi. Mengingat belum adanya pelaporan jenis Arthropoda dan Echinodermata di zona pasang surut Pantai Gatra, maka dilakukan penelitian inventarisasi di daerah ini. Tujuan penelitian ini adalah invetarisasi jenis Arthropoda dan Echinodermata. Hasil penelitian tentang inventarisasi jenis Arthropoda dan Echinodermata di zona pasang surut pantai Gatra Kabupaten Malang, secara keseluruhan ditemukan 14 jenis, 13 genus, dan 11 famili dari filum Arthropoda dan Echinodermata.

  15. Global diversity of brittle stars (Echinodermata: Ophiuroidea).

    Science.gov (United States)

    Stöhr, Sabine; O'Hara, Timothy D; Thuy, Ben

    2012-01-01

    This review presents a comprehensive overview of the current status regarding the global diversity of the echinoderm class Ophiuroidea, focussing on taxonomy and distribution patterns, with brief introduction to their anatomy, biology, phylogeny, and palaeontological history. A glossary of terms is provided. Species names and taxonomic decisions have been extracted from the literature and compiled in The World Ophiuroidea Database, part of the World Register of Marine Species (WoRMS). Ophiuroidea, with 2064 known species, are the largest class of Echinodermata. A table presents 16 families with numbers of genera and species. The largest are Amphiuridae (467), Ophiuridae (344 species) and Ophiacanthidae (319 species). A biogeographic analysis for all world oceans and all accepted species was performed, based on published distribution records. Approximately similar numbers of species were recorded from the shelf (n = 1313) and bathyal depth strata (1297). The Indo-Pacific region had the highest species richness overall (825 species) and at all depths. Adjacent regions were also relatively species rich, including the North Pacific (398), South Pacific (355) and Indian (316) due to the presence of many Indo-Pacific species that partially extended into these regions. A secondary region of enhanced species richness was found in the West Atlantic (335). Regions of relatively low species richness include the Arctic (73 species), East Atlantic (118), South America (124) and Antarctic (126).

  16. Patterns and Drivers of Egg Pigment Intensity and Colour Diversity in the Ocean: A Meta-Analysis of Phylum Echinodermata.

    Science.gov (United States)

    Montgomery, E M; Hamel, J-F; Mercier, A

    Egg pigmentation is proposed to serve numerous ecological, physiological, and adaptive functions in egg-laying animals. Despite the predominance and taxonomic diversity of egg layers, syntheses reviewing the putative functions and drivers of egg pigmentation have been relatively narrow in scope, centring almost exclusively on birds. Nonvertebrate and aquatic species are essentially overlooked, yet many of them produce maternally provisioned eggs in strikingly varied colours, from pale yellow to bright red or green. We explore the ways in which these colour patterns correlate with behavioural, morphological, geographic and phylogenetic variables in extant classes of Echinodermata, a phylum that has close phylogenetic ties with chordates and representatives in nearly all marine environments. Results of multivariate analyses show that intensely pigmented eggs are characteristic of pelagic or external development whereas pale eggs are commonly brooded internally. Of the five egg colours catalogued, orange and yellow are the most common. Yellow eggs are a primitive character, associated with all types of development (predominant in internal brooders), whereas green eggs are always pelagic, occur in the most derived orders of each class and are restricted to the Indo-Pacific Ocean. Orange eggs are geographically ubiquitous and may represent a 'universal' egg pigment that functions well under a diversity of environmental conditions. Finally, green occurs chiefly in the classes Holothuroidea and Ophiuroidea, orange in Asteroidea, yellow in Echinoidea, and brown in Holothuroidea. By examining an unprecedented combination of egg colours/intensities and reproductive strategies, this phylum-wide study sheds new light on the role and drivers of egg pigmentation, drawing parallels with theories developed from the study of more derived vertebrate taxa. The primary use of pigments (of any colour) to protect externally developing eggs from oxidative damage and predation is

  17. Reproductive cycle of Loxechinus albus (Echinodermata: Echinoidea in two areas of the Magellan Region (53ºS, 70-72ºW, Chile

    Directory of Open Access Journals (Sweden)

    Sylvia T. Oyarzún

    1999-12-01

    Full Text Available The reproductive cycle of the Chilean edible sea urchin, Loxechinus albus, was studied in two areas of the Magellan region, the Cockburn Channel (53°43´S, 70°42´W and Dawson Island (53°43´S, 72°00´W. Eleven monthly samplings were carried out from April 1996 to May 1997 in each area and samples of between 88 and 100 organisms were collected. Test diameter, total wet weight, and wet gonad weight was measured for each organism. Sex, gonad index, maturity index and gametogenic condition were estimated for each organism through histological analyses. The results indicate that L. albus in the Magellan region has an annual reproductive cycle in which the temporal sequence of different gametogenic processes can not be distinguished accurately due to the rapid and continuous gonadal recovery and gamete production after the spawning period. Although mature organisms were present most of the year, simultaneous spawning of males and females occurred from August to September in Dawson Island and from July to September in the Cockburn Channel. Gametes of those organisms that became mature after the spawning period were resorbed by nutritive phagocytes. Results from this study suggest that small-scale variability of spawning period in the Magellan region may be explained by the differences in food type and availability among areas. Our results also suggest that the Magellan region is an exception to the latitudinal pattern of spawning period reported for most of the Chilean coast. This large-scale variability may be explained by the simultaneous occurrence of low temperatures and short days during late winter and early spring.

  18. Chronic toxicity test with sea urchin Echinometra lucunter and Lytechinus variegatus (Echinodermata: Echinoidea, exposed to light-stick - flag paternoster used for longline surface fishing

    Directory of Open Access Journals (Sweden)

    Caio Cesar-Ribeiro

    2010-06-01

    Full Text Available In this work, the chronic toxicity of a mixture of light-stick chemicals and water was tested. The light-stick is used in fishery activities to catch swordfish. The tubes were collected on the beaches of the Costa dos Coqueiros - BA, Brazil, in the period from 14th to 31st July 2007. The method used was a short chronic toxicity test where embryos of the sea urchins Echinometra lucunter and Lytechinus variegatus were exposed to a stock solution consisting of the supernatant formed from a mixture of sea water and the orange-colored light-stick chemical. After a preliminary test, concentrations defined were 0.002, 0.003, 0.01, 0.02, 0.1, 1.0% of stock solution. The final test ran for 36 hours for E. Lucunter and 24 hours for L. variegatus with 4 replicates for each concentration. The value of EC50 - 36h was 0.062% with confidence limits ranging from 0.042 to 0.079% and the EC50 - 24h was 0.011% with confidence limits ranging from 0.009 to 0.014%, i.e., the chemical mix present in the light-stick is potentially toxic. So, as these flags are commonly used for fishing there is potential danger in their disposal in the open ocean.O objetivo deste trabalho foi avaliar a toxicidade crônica da água do mar em contato com o líquido contido no light-stick, sinalizador utilizado em pesca de espinhel de superfície para a captura de espadarte. Os tubos foram coletados nas praias da Costa dos Coqueiros - BA, no período de 14 a 31 de Julho de 2007. O método utilizado para a verificação da toxicidade crônica foi o teste de curta duração com embriões de ouriço-do-mar Echinometra lucunter e Lytechinus variegatus, os ensaios foram realizados com solução estoque que consiste do sobrenadante formado a partir de uma mistura de água do mar com o líquido do sinalizador de coloração laranja. Após um teste preliminar as concentrações definidas foram 0.002; 0.003; 0.01; 0.02; 0.1; 1.0%. O teste definitivo teve duração de 36 horas para E. lucunter e 24 horas para L. variegatus, sendo preparadas 4 réplicas para cada concentração. O valor da CE50 - 36h encontrado foi de 0.062% com limites de aceitabilidade variando de 0.042 a 0.079% e a CE50 - 24h encontrada foi de 0.011% com limites de aceitabilidade variando de 0.009 a 0.014%, ou seja, os compostos químicos presentes no light-stick são potencialmente tóxicos. Portanto já que esses sinalizadores são utilizados comumente como petrechos de pesca há a necessidade de que eles sejam recolhidos, pois podem causar efeitos adversos quando abrem nos oceanos.

  19. Density of Diadema antillarum (Echinodermata: Echinoidea) on live coral patch reefs and dead Acropora cervicornis rubble patches near Loggerhead Key, Dry Tortugas National Park, Florida, USA

    Science.gov (United States)

    Density of adult Diadema antillarum was assessed on live coral patch reefs and dead Acropora cervicornis rubble patches next to Loggerhead Key, Dry Tortugas National Park, Florida, USA in June 2009. Mean density on live coral patch reefs (0.49 individuals m-2) was not statistical...

  20. A new species of Diadema (Echinodermata: Echinoidea: Diadematidae) from the eastern Atlantic Ocean and a neotype designation of Diadema antillarum (Philippi, 1845).

    Science.gov (United States)

    Rodoríguez, Adriana; Hernández, José Carlos; Clemente, Sabrina; Coppard, Simon Edward

    2013-01-01

    Diadenia africanum sp. nov. Rodríguez et al. 2013 occurs in the eastern Atlantic Ocean at depths of 1-80 meters off Ma- deira Islands, Salvage Islands, Canary Islands, Cape Verde Islands, Sâo Tome Islands and at the continental coast off Sen- egal and Ghana. This species was previously considered an eastern Atlantic population of D. antillarum. Genetic distances between the holotype of D. africanum and the neotype of D. antillarun herein designated, measured 3.34% in Cytochrome oxidase I, 3.80% in ATPase-8 and 2.31% in ATPase-6. Such divergence is similar to that already highlighted between other accepted species of Diadena. Morphometric analysis of test, spine and pedicellarial characters also separated D. africanum from D. antillartn and reveals that this new species is morphologically similar to D. antillarum ascensionis from the mid Atlantic. The tridentate pedicellariae, which have been shown to have diagnostic characters which discriminate among species of Diadema, occur as both broad and narrow valved forms in D. antillarumn from the western Atlantic. In D. africanum the tridentate pedicellariae occur only as a single form which is characterized by moderately broad and curved valves, with an expanded distal gripping region. This form of tridentate pedicellaria is very similar to that of D. antillarum ascensionis from the central Atlantic, with only slight variations in valve serration and valve curvature differ- entiating the two forms.

  1. Mechanical properties of the compass depressors of the sea-urchin Paracentrotus lividus (Echinodermata, Echinoidea) and the effects of enzymes, neurotransmitters and synthetic tensilin-like protein.

    Science.gov (United States)

    Wilkie, Iain C; Fassini, Dario; Cullorà, Emanuele; Barbaglio, Alice; Tricarico, Serena; Sugni, Michela; Del Giacco, Luca; Candia Carnevali, M Daniela

    2015-01-01

    The compass depressors (CDs) of the sea-urchin lantern are ligaments consisting mainly of discontinuous collagen fibrils associated with a small population of myocytes. They are mutable collagenous structures, which can change their mechanical properties rapidly and reversibly under nervous control. The aims of this investigation were to characterise the baseline (i.e. unmanipulated) static mechanical properties of the CDs of Paracentrotus lividus by means of creep tests and incremental force-extension tests, and to determine the effects on their mechanical behaviour of a range of agents. Under constant load the CDs exhibited a three-phase creep curve, the mean coefficient of viscosity being 561±365 MPa.s. The stress-strain curve showed toe, linear and yield regions; the mean strain at the toe-linear inflection was 0.86±0.61; the mean Young's modulus was 18.62±10.30 MPa; and the mean tensile strength was 8.14±5.73 MPa. Hyaluronidase from Streptomyces hyalurolyticus had no effect on creep behaviour, whilst chondroitinase ABC prolonged primary creep but had no effect on secondary creep or on any force-extension parameters; it thus appears that neither hyaluronic acid nor sulphated glycosaminoglycans have an interfibrillar load transfer function in the CD. Acetylcholine, the muscarinic agonists arecoline and methacholine, and the nicotinic agonists nicotine and 1-[1-(3,4-dimethyl-phenyl)-ethyl]-piperazine produced an abrupt increase in CD viscosity; the CDs were not differentially sensitive to muscarinic or nicotinic agonists. CDs showed either no, or no consistent, response to adrenaline, L-glutamic acid, 5-hydroxytryptamine and γ-aminobutyric acid. Synthetic echinoid tensilin-like protein had a weak and inconsistent stiffening effect, indicating that, in contrast to holothurian tensilins, the echinoid molecule may not be involved in the regulation of collagenous tissue tensility. We compare in detail the mechanical behaviour of the CD with that of mammalian tendon and highlight its potential as a model system for investigating poorly understood aspects of the ontogeny and phylogeny of vertebrate collagenous tissues.

  2. Spatial distribution patterns and population structure of the sea urchin Paracentrotus lividus (Echinodermata: Echinoidea, in the coastal fishery of western Sardinia: a geostatistical analysis

    Directory of Open Access Journals (Sweden)

    Piero Addis

    2012-12-01

    Full Text Available The identification of appropriate spatial distribution patterns for the observation, analysis and management of stocks with a persistent spatial structure, such as sea urchins, is a key issue in fish ecology and fisheries research. This paper describes the development and application of a geostatistical approach for determining the spatial distribution and resilience of the population of the sea urchin Paracentrotus lividus in a fishing ground of western Sardinia (western Mediterranean. A framework combining field data collection, experimental modelling and mapping was used to identify the best-fit semivariogram, taking pre-fishing and post-fishing times into consideration. Variographic analyses indicate autocorrelation of density at small distances, while the isotropic Gaussian and spherical models are suitable for describing the spatial structure of sea urchin populations. The point kriging technique highlights a generally patchy population distribution that tends to disappear during the fishing season. Kriging maps are also useful for calculating predictable stock abundances, and thus mortality rates, by class diameters within six months of fishing. We conclude that the framework proposed is adequate for biomass estimation and assessment of sea urchin resources. This framework can therefore be regarded as a useful tool for encouraging a science-based management of this fishery.

  3. The effects of chronic inorganic and organic phosphate exposure on bactericidal activity of the coelomic fluid of the sea urchin Lytechinus variegatus (Lamarck) (Echinodermata: Echinoidea).

    Science.gov (United States)

    Böttger, S Anne; McClintock, James B

    2009-07-01

    The sea urchin Lytechinus variegatus can survive chronic exposure to sodium phosphate (inorganic phosphate) concentrations as high as 3.2 mg L-1, and triethyl phosphate (organic phosphate) concentrations of 1000 mg L-1. However, chronic exposure to low (0.8 mg L-1 inorganic and 10 mg L-1 organic phosphate), medium (1.6 mg L-1 inorganic and 100 mg L-1 organic phosphate) or high (3.2 mg L-1 inorganic and 1000 mg L-1 organic phosphate) sublethal concentrations of these phosphates inhibit bactericidal clearance of the marine bacterium Vibrio sp. Bacteria were exposed to coelomic fluid collected from individuals maintained in either artificial seawater, or three concentrations of either inorganic phosphate or organic phosphate. Sterile marine broth, natural seawater and cell free coelomic fluid (cfCF) were employed as controls. Bacterial survival indices were measured at 0, 24 and 48 h periods once a week for four weeks. Bacteria were readily eliminated from the whole coelomic fluid (wCF) of individuals maintained in artificial seawater. Individuals maintained in inorganic phosphates were able to clear bacteria following a two week exposure period, while individuals maintained at even low concentrations of organic phosphates failed to clear all bacteria from their coelomic fluid. Exposure to phosphates represses antimicrobial defenses and may ultimately compromise survival of L. variegatus in the nearshore environment.

  4. Mechanical properties of the compass depressors of the sea-urchin Paracentrotus lividus (Echinodermata, Echinoidea and the effects of enzymes, neurotransmitters and synthetic tensilin-like protein.

    Directory of Open Access Journals (Sweden)

    Iain C Wilkie

    Full Text Available The compass depressors (CDs of the sea-urchin lantern are ligaments consisting mainly of discontinuous collagen fibrils associated with a small population of myocytes. They are mutable collagenous structures, which can change their mechanical properties rapidly and reversibly under nervous control. The aims of this investigation were to characterise the baseline (i.e. unmanipulated static mechanical properties of the CDs of Paracentrotus lividus by means of creep tests and incremental force-extension tests, and to determine the effects on their mechanical behaviour of a range of agents. Under constant load the CDs exhibited a three-phase creep curve, the mean coefficient of viscosity being 561±365 MPa.s. The stress-strain curve showed toe, linear and yield regions; the mean strain at the toe-linear inflection was 0.86±0.61; the mean Young's modulus was 18.62±10.30 MPa; and the mean tensile strength was 8.14±5.73 MPa. Hyaluronidase from Streptomyces hyalurolyticus had no effect on creep behaviour, whilst chondroitinase ABC prolonged primary creep but had no effect on secondary creep or on any force-extension parameters; it thus appears that neither hyaluronic acid nor sulphated glycosaminoglycans have an interfibrillar load transfer function in the CD. Acetylcholine, the muscarinic agonists arecoline and methacholine, and the nicotinic agonists nicotine and 1-[1-(3,4-dimethyl-phenyl-ethyl]-piperazine produced an abrupt increase in CD viscosity; the CDs were not differentially sensitive to muscarinic or nicotinic agonists. CDs showed either no, or no consistent, response to adrenaline, L-glutamic acid, 5-hydroxytryptamine and γ-aminobutyric acid. Synthetic echinoid tensilin-like protein had a weak and inconsistent stiffening effect, indicating that, in contrast to holothurian tensilins, the echinoid molecule may not be involved in the regulation of collagenous tissue tensility. We compare in detail the mechanical behaviour of the CD with that of mammalian tendon and highlight its potential as a model system for investigating poorly understood aspects of the ontogeny and phylogeny of vertebrate collagenous tissues.

  5. Opportunistic responses of Diadema antillarum (Echinodermata: Echinoidea) populations following the 1997 98 El Niño event in Bahia, Brazil

    Science.gov (United States)

    Attrill, Martin J.; Kelmo, Francisco

    2007-06-01

    We present results from a seven year (1995-2001) study on the coral reefs in Bahia (Brazil), the reef invertebrate community being severely impacted by the 1997-98 El Niño Southern Oscillation event. Despite local extinction of some taxa, the urchin Diadema antillarum was the only species out of a total of 678 enumerated demonstrating a significant increase in population size following El Niño, indicating a unique response of this species to the stresses associated with these events. Other species of echinoid did not show such a response, most disappearing from the fauna during the two post-El Niño years. The increasing Diadema numbers were most likely due to movement of individuals onto the reef systems from deeper water, exploiting the conditions on the reefs caused by a reduction in competitors and, we speculate, an increase in available space on the reef allowing potential algal settlement to sustain this elevated urchin population. This increased grazing pressure may have prevented algae covering the reef, as seen in other Atlantic reef systems, allowing new coral settlement in 2001.

  6. Two new species of Syndesmis (Platyhelminthes, Rhabdocoela, Umagillidae from the sea urchin Pseudechinus magellanicus (Echinodermata, Echinoidea in the Southwestern Atlantic Ocean

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    Francisco Brusa

    2017-08-01

    Full Text Available In this paper, we describe two new species of Syndesmis living in Pseudechinus magellanicus in the Southwest Atlantic Ocean. The new species have a long stylet in the male reproductive system, which is different from that of the known species of the genus. Specimens of Syndesmis selknami n. sp. have a ∼220-μm-long stylet (∼1/3 of the body length, 0.69 mm. This ratio is unique because only four species (Syndesmis echinorum, Syndesmis rubida, Syndesmis inconspicua and Syndesmis echiniacuti have similar stylet lengths but are larger in body sizes (3–5 mm. Specimens of Syndesmis aonikenki n. sp. have a ∼148-μm-long stylet (∼1/10 of the body length, 1.11 mm. Syndesmis pallida has a similar ratio but the uterus is located posteriorly, and the filament glands are very small and located in the posterior region of the body. These are the first flatworms reported parasitizing Pseudechinus magellanicus.

  7. THE SAND DOLLAR PARASCUTELLA (ECHINOIDEA IN THE LATE BADENIAN OF CROATIA

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    GORAN MIKSA

    2009-03-01

    Full Text Available The echinoid Parascutella gibbercula (de Serres, 1829 (Echinoidea: Clypeasteroida is reported from the Mali Potok area of the Medvednica Mountain in Croatia. The fossil site is situated in mixed siliciclastics and biocalcarenites of late Badenian age. These echinoids are large extremely flat echinoids, informally known as sand dollars. The discovered echinoids are preserved in situ. The environment of deposition is defined as a shallow, coastal, high-energy environment for which these sea-urchins have developed characteristic morphological features. The strength and hydrodynamic stability of their shells enabled the post-mortal colonisation of the skeleton by epibenthic organisms, creating a robust, relatively stable substrate within otherwise mobile, unconsolidated sediments (secondary hardground. The Mali Potok echinoid assemblage has an unusual taxonomic composition for the Late Miocene of Croatia. 

  8. Triterpene glycosides of sea cucumbers (Holothuroidea, Echinodermata) as taxonomic markers.

    Science.gov (United States)

    Kalinin, Vladimir I; Avilov, Sergey A; Silchenko, Alexandra S; Stonik, Valentin A

    2015-01-01

    Triterpene glycosides are characteristic metabolites of sea cucumbers (Holothurioidea, Echinodermata). The majority of the glycosides belong to the holostane type {lanostane derivatives with an 18(20)-lactone}. Carbohydrate chains of these glycosides contain xylose, glucose, quinovose, 3-O-methylglucose, and, rarely, 3-O-methylxylose, 3-O-methylglucuronic acid, 3-O-methylquinovose, and 6-O-acetyl-glucose. The glycosides are specific for genera, groups of genera and even for species. The advantages and problems in the use of triterpene glycosides as taxonomic markers in the systematics of sea cucumbers are discussed.

  9. Delaware River Dredging Disposal Study, Stage 1 Reconnaissance Report.

    Science.gov (United States)

    1979-06-01

    Microporellidae MiiSrorefla ciliata (Pallas 1766) SF X Phylum Echinodermata Class Echinoidea Order Diadematoida * Family Lchinrachnidae *Echinarachnius pdrma...Microporella ciliata (Pallas 1766) SF x Phylum Echinodermata Class Echinoidea Order Diadematoida Family Echinarachnidae Echinarachnius prina- (Lamark 1816...establishment of estuarine plant and animal communities. Fossil pollen samples, wood and peat species and extinct megafaunal remains (mammoth, mastodon

  10. A simple enzymatic method for examining calcite ossicles of Echinodermata.

    Science.gov (United States)

    Tiago, C G; Brites, A D; Kawauchi, G Y

    2005-06-01

    The various shapes, size and fine details of ossicles are of paramount importance as systematic characters in the Echinodermata. The ossicles in this group are endodermal and a method to free them from the dermis is essential for their study. To date, a small quantity of hypochlorite solution (usually household liquid bleach) has been used to dissolve a small piece of tissue and, consequently, free these ossicles. A new method, using a proteolytic enzyme instead of hypochlorite solution to dissolve holothurian tissues, is proposed. This method was tested on fragments of body tissues from three species in three different orders of holothurians: Holothuria grisea Selenka, 1867 (Aspidochirotida), Duasmodactyla seguroensis (Deichmann, 1930) (Dendrochirotida) and Synaptula secreta Ancona Lopez (1957) (Apodida). Observations of material prepared using the hypochlorite and the enzyme methods were made using scanning electron microscopy (SEM). The SEM images show the striking differences in the surface of the ossicles obtained by each method, and reveal the advantages of the enzyme method.

  11. Echinodermata from São Sebastião Channel (São Paulo, Brazil).

    Science.gov (United States)

    Netto, L F; Hadel, V F; Tiago, C G

    2005-12-01

    Faunal inventories are extremely important, especially when focused on neglected groups, such as echinoderms, and concentrated on areas under intense anthropic activity such as the SAo Sebastilo Channel in Brazil (23 degrees 41' - 23 degrees 54' S and 45 degrees 19' - 45 degrees 30' W). Intertidal and upper sublittoral zone collections were performed at five sites of the Channel's continental margin from May to August 2001. The rocky substrate down to 19 m deep was surveyed by snorkeling and SCUBA diving from August 2002 to May 2004, on both margins of the Channel: continental (14 sites) and insular (10 sites). We report a total of 38 species of echinoderms (one Crinoidea, nine Asteroidea, 13 Ophiuroidea, nine Echinoidea and six Holothuroidea). Seven of those species have been recorded here for the first time for the Channel (four Asteroidea, two Ophiuroidea and one Echinoidea).

  12. Echinodermata das praias de Salvador (Bahia, Brasil The Echinoderms of Salvador beaches (Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Orane Falcão de Souza Alves

    2000-06-01

    Full Text Available This paper presents 28 species of Echinoderms collected on 5 beaches of Salvador (12º54' to 13º01' S and 38º26' to 38º33' W, Brazil, which are distributed in 19 families. Ophiuroidea represented 53,6% of the collected species, followed by Echinoidea (28,6%, Asteroidea (7,1%, Holothuroidea (7,1%, and Crinoidea (3,6%. Ophiuroidea and Echinoidea were the most frequent groups, occurring at all the studied beaches while Crinoidea occurred only on 20% of them. Most of the species are characterized as belonging to the tropical warm waters, some to the shallow coastal areas and some having a broad bathymetric distribution. The richness of species values on beaches ranged from 7 to 24, at Itapua Beach, and from 2 to 14 among different kinds of habitats, where protected ones showed higher values.

  13. Geinitzaster gen.n. (Asteroidea, Echinodermata) from the Upper Cenomanian strata of the Bohemian Cretaceous Basin

    Czech Academy of Sciences Publication Activity Database

    Žítt, Jiří

    2005-01-01

    Roč. 56, č. 4 (2005), s. 317-326 ISSN 1335-0552 R&D Projects: GA ČR GA206/01/1580 Institutional research plan: CEZ:AV0Z3013912 Keywords : Cenomanian * Asteroidea * Echinodermata Subject RIV: EG - Zoology Impact factor: 0.449, year: 2005 http://www.geologicacarpathica.sk/src/main.php

  14. Late Turonian ophiuroids (Echinodermata) from the Bohemian Cretaceous Basin, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Štorc, R.; Žítt, Jiří

    2008-01-01

    Roč. 83, č. 2 (2008), s. 123-140 ISSN 1214-1119 R&D Projects: GA ČR GA205/06/0842 Institutional research plan: CEZ:AV0Z30130516 Keywords : Echinodermata * Ophiuroidea * Upper Cretaceous * taxonomy * Bohemian Cretaceous Basin Subject RIV: DB - Geology ; Mineralogy

  15. A novel report of hatching plasticity in the phylum Echinodermata.

    Science.gov (United States)

    Armstrong, A Frances; Blackburn, Holly N; Allen, Jonathan D

    2013-02-01

    Hatching plasticity occurs in response to a wide range of stimuli across many animal taxa, including annelids, arthropods, mollusks, and chordates. Despite the prominence of echinoderms in developmental biology and more than 100 years of detailed examination of their development under a variety of conditions, environmentally cued hatching plasticity has never been reported in the phylum Echinodermata. Here we report plasticity in the timing and stage of hatching of embryos of the sand dollar Echinarachnius parma in response to reductions in salinity. Embryos of E. parma increased their time to hatching more than twofold in response to ecologically relevant salinity reductions, while maintaining an otherwise normal developmental schedule. Embryos that experienced the greatest delay in hatching time emerged from the fertilization envelope as four-arm pluteus larvae rather than hatching as blastulae or early gastrulae. Salinity manipulations across multiple male-female pairs indicated high variability in hatching time both within and among clutches, suggesting significant intraspecific variation in developmental responses to salinity.

  16. Global diversity and phylogeny of the Asteroidea (Echinodermata).

    Science.gov (United States)

    Mah, Christopher L; Blake, Daniel B

    2012-01-01

    Members of the Asteroidea (phylum Echinodermata), popularly known as starfish or sea stars, are ecologically important and diverse members of marine ecosystems in all of the world's oceans. We present a comprehensive overview of diversity and phylogeny as they have figured into the evolution of the Asteroidea from Paleozoic to the living fauna. Living post-Paleozoic asteroids, the Neoasteroidea, are morphologically separate from those in the Paleozoic. Early Paleozoic asteroid faunas were diverse and displayed morphology that foreshadowed later living taxa. Preservation presents significant difficulties, but fossil occurrence and current accounts suggests a diverse Paleozoic fauna, which underwent extinction around the Permian-Triassic interval was followed by re-diversification of at least one surviving lineage. Ongoing phylogenetic classification debates include the status of the Paxillosida and the Concentricycloidea. Fossil and molecular evidence has been and continues to be part of the ongoing evolution of asteroid phylogenetic research. The modern lineages of asteroids include the Valvatacea, the Forcipulatacea, the Spinlosida, and the Velatida. We present an overview of diversity in these taxa, as well as brief notes on broader significance, ecology, and functional morphology of each. Although much asteroid taxonomy is stable, many new taxa remain to be discovered with many new species currently awaiting description. The Goniasteridae is currently one of the most diverse families within the Asteroidea. New data from molecular phylogenetics and the advent of global biodiversity databases, such as the World Asteroidea Database (http://www.marinespecies.org/Asteroidea/) present important new springboards for understanding the global biodiversity and evolution of asteroids.

  17. Global diversity and phylogeny of the Asteroidea (Echinodermata.

    Directory of Open Access Journals (Sweden)

    Christopher L Mah

    Full Text Available Members of the Asteroidea (phylum Echinodermata, popularly known as starfish or sea stars, are ecologically important and diverse members of marine ecosystems in all of the world's oceans. We present a comprehensive overview of diversity and phylogeny as they have figured into the evolution of the Asteroidea from Paleozoic to the living fauna. Living post-Paleozoic asteroids, the Neoasteroidea, are morphologically separate from those in the Paleozoic. Early Paleozoic asteroid faunas were diverse and displayed morphology that foreshadowed later living taxa. Preservation presents significant difficulties, but fossil occurrence and current accounts suggests a diverse Paleozoic fauna, which underwent extinction around the Permian-Triassic interval was followed by re-diversification of at least one surviving lineage. Ongoing phylogenetic classification debates include the status of the Paxillosida and the Concentricycloidea. Fossil and molecular evidence has been and continues to be part of the ongoing evolution of asteroid phylogenetic research. The modern lineages of asteroids include the Valvatacea, the Forcipulatacea, the Spinlosida, and the Velatida. We present an overview of diversity in these taxa, as well as brief notes on broader significance, ecology, and functional morphology of each. Although much asteroid taxonomy is stable, many new taxa remain to be discovered with many new species currently awaiting description. The Goniasteridae is currently one of the most diverse families within the Asteroidea. New data from molecular phylogenetics and the advent of global biodiversity databases, such as the World Asteroidea Database (http://www.marinespecies.org/Asteroidea/ present important new springboards for understanding the global biodiversity and evolution of asteroids.

  18. Circumpolar dataset of sequenced specimens of Promachocrinus kerguelensis (Echinodermata, Crinoidea).

    Science.gov (United States)

    Hemery, Lenaïg G; Améziane, Nadia; Eléaume, Marc

    2013-01-01

    This circumpolar dataset of the comatulid (Echinodermata: Crinoidea) Promachocrinus kerguelensis (Carpenter, 1888) from the Southern Ocean, documents biodiversity associated with the specimens sequenced in Hemery et al. (2012). The aim of Hemery et al. (2012) paper was to use phylogeographic and phylogenetic tools to assess the genetic diversity, demographic history and evolutionary relationships of this very common and abundant comatulid, in the context of the glacial history of the Antarctic and Sub-Antarctic shelves (Thatje et al. 2005, 2008). Over one thousand three hundred specimens (1307) used in this study were collected during seventeen cruises from 1996 to 2010, in eight regions of the Southern Ocean: Kerguelen Plateau, Davis Sea, Dumont d'Urville Sea, Ross Sea, Amundsen Sea, West Antarctic Peninsula, East Weddell Sea and Scotia Arc including the tip of the Antarctic Peninsula and the Bransfield Strait. We give here the metadata of this dataset, which lists sampling sources (cruise ID, ship name, sampling date, sampling gear), sampling sites (station, geographic coordinates, depth) and genetic data (phylogroup, haplotype, sequence ID) for each of the 1307 specimens. The identification of the specimens was controlled by an expert taxonomist specialist of crinoids (Marc Eléaume, Muséum national d'Histoire naturelle, Paris) and all the COI sequences were matched against those available on the Barcode of Life Data System (BOLD: http://www.boldsystems.org/index.php/IDS_OpenIdEngine). This dataset can be used by studies dealing with, among other interests, Antarctic and/or crinoid diversity (species richness, distribution patterns), biogeography or habitat / ecological niche modeling. This dataset is accessible through the GBIF network at http://ipt.biodiversity.aq/resource.do?r=proke.

  19. [Echinoderms (Echinodermata) from the Mexican waters of the Gulf of Mexico].

    Science.gov (United States)

    Durán-González, Alicia; Laguarda-Figueras, Alfredo; Solís-Marin, Francisco A; Buitrón Sánchez, Blanca Estela; Ahearn, Cynthia Gust; Torres-Vega, Juan

    2005-12-01

    We present a systematic list of the echinoderms from Gulf of Mexico's Mexican waters based on specimens of the Colecci6n Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Aut6noma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. This list reveals an important echinoderm biodiversity present in the Gulf of Mexico, where five of the six echinoderm classes are represented. A total of 209 echinoderm species is recorded, distributed in 129 genera, 63 families and 25 orders. 31 new records for the Gulf of Mexico are presented: Asteroidea (16), Ophiuroidea (nine), Echinoidea (one) and Holothuroidea (five).

  20. Brittle-stars (Echinodermata: Ophiuroidea) from the continental shelf and upper slope of the Colombian Caribbean

    OpenAIRE

    Borrero-Pérez, G. H.; Benavides-Serrato, M.; Solano, Ó.; Navas S., G. R.

    2016-01-01

    An annotated brittle star list (Echinodermata: Ophiuroidea) collected by bottom trawling between 20 and 520 m depth during the INVEMAR-MACROFAUNA campaigns (1998-2001) along the continental shelf and upper slope of the Colombian Caribbean is presented. A total of 58 species were identified: 41 genera, 13 families and 2 orders, in which 35 species are new records for the Colombian Caribbean (28 are also new for the continental part of the Caribbean Sea). General and detailed figures are provid...

  1. Bioactive substances with anti-neoplastic efficacy from marine invertebrates: Bryozoa, Mollusca, Echinodermata and Urochordata

    Science.gov (United States)

    Sima, Peter; Vetvicka, Vaclav

    2011-01-01

    The marine environment provides a rich source of natural products with potential therapeutic application. This has resulted in an increased rate of pharmaceutical agents being discovered in marine animals, particularly invertebrates. Our objective is to summarize the most promising compounds which have the best potential and may lead to use in clinical practice, show their biological activities and highlight the compounds currently being tested in clinical trials. In this paper, we focused on Bryozoa, Mollusca, Echinodermata and Urochordata. PMID:22087434

  2. Computational Fluid Dynamics Analysis of the Fossil Crinoid Encrinus liliiformis (Echinodermata: Crinoidea)

    OpenAIRE

    Dynowski, Janina F.; Nebelsick, James H.; Klein, Adrian; Roth-Nebelsick, Anita

    2016-01-01

    Crinoids, members of the phylum Echinodermata, are passive suspension feeders and catch plankton without producing an active feeding current. Today, the stalked forms are known only from deep water habitats, where flow conditions are rather constant and feeding velocities relatively low. For feeding, they form a characteristic parabolic filtration fan with their arms recurved backwards into the current. The fossil record, in contrast, provides a large number of stalked crinoids that lived in ...

  3. Systematic comparison and reconstruction of sea urchin (Echinoidea) internal anatomy: a novel approach using magnetic resonance imaging.

    Science.gov (United States)

    Ziegler, Alexander; Faber, Cornelius; Mueller, Susanne; Bartolomaeus, Thomas

    2008-07-23

    Traditional comparative morphological analyses and subsequent three-dimensional reconstructions suffer from a number of drawbacks. This is particularly evident in the case of soft tissue studies that are technically demanding, time-consuming, and often prone to produce artefacts. These problems can partly be overcome by employing non-invasive, destruction-free imaging techniques, in particular micro-computed tomography or magnetic resonance imaging. Here, we employed high-field magnetic resonance imaging techniques to gather numerous data from members of a major marine invertebrate taxon, the sea urchins (Echinoidea). For this model study, 13 of the 14 currently recognized high-ranking subtaxa (orders) of this group of animals were analyzed. Based on the acquired datasets, interactive three-dimensional models were assembled. Our analyses reveal that selected soft tissue characters can even be used for phylogenetic inferences in sea urchins, as exemplified by differences in the size and shape of the gastric caecum found in the Irregularia. The main focus of our investigation was to explore the possibility to systematically visualize the internal anatomy of echinoids obtained from various museum collections. We show that, in contrast to classical preparative procedures, magnetic resonance imaging can give rapid, destruction-free access to morphological data from numerous specimens, thus extending the range of techniques available for comparative studies of invertebrate morphology.

  4. Systematic comparison and reconstruction of sea urchin (Echinoidea internal anatomy: a novel approach using magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Mueller Susanne

    2008-07-01

    Full Text Available Abstract Background Traditional comparative morphological analyses and subsequent three-dimensional reconstructions suffer from a number of drawbacks. This is particularly evident in the case of soft tissue studies that are technically demanding, time-consuming, and often prone to produce artefacts. These problems can partly be overcome by employing non-invasive, destruction-free imaging techniques, in particular micro-computed tomography or magnetic resonance imaging. Results Here, we employed high-field magnetic resonance imaging techniques to gather numerous data from members of a major marine invertebrate taxon, the sea urchins (Echinoidea. For this model study, 13 of the 14 currently recognized high-ranking subtaxa (orders of this group of animals were analyzed. Based on the acquired datasets, interactive three-dimensional models were assembled. Our analyses reveal that selected soft tissue characters can even be used for phylogenetic inferences in sea urchins, as exemplified by differences in the size and shape of the gastric caecum found in the Irregularia. Conclusion The main focus of our investigation was to explore the possibility to systematically visualize the internal anatomy of echinoids obtained from various museum collections. We show that, in contrast to classical preparative procedures, magnetic resonance imaging can give rapid, destruction-free access to morphological data from numerous specimens, thus extending the range of techniques available for comparative studies of invertebrate morphology.

  5. Crustaceans associated with Cnidaria, Bivalvia, Echinoidea and Pisces at São Tomé and Príncipe islands.

    Directory of Open Access Journals (Sweden)

    Wirtz, P.

    2008-01-01

    Full Text Available Symbiotic crustaceans were searched for at sea anemones (Actiniaria, encrusting anemones (Zoantharia, horny coral (Gorgonaria, black coral (Antipatharia, bivalves (Bivalvia, and sea urchins (Echinoidea at São Tomé and Príncipe Islands (Gulf of Guinea, eastern central Atlantic. Sixteen species of crustaceans were found in association with these invertebrate hosts; eleven of them were new records for the area and two species, belonging to the genera Hippolyte and Heteromysis, were new for science. The thalassinid Axiopsis serratifrons was occasionally associated with an undescribed species of gobiid fish.

  6. [Catalogue of neritic-benthonic echinoderms (Echinodermata: Asteroidea and Ophiuroidea) from the Cuban Archipelago].

    Science.gov (United States)

    Abreu-Pérez, Mercedes; Solís-Marín, Francisco A; Laguarda-Figueras, Alfredo

    2005-12-01

    This is an updated taxonomic catalogue of neritic-benthonic Echinodermata (Asteroidea and Ophiuroidea) from Cuba, that includes locality, range, habitat and depth where each species is found. The species list is based on the collections of the Oceanology Institute; Havana; the "Felipe Poey" Museum (Havana University) and the National Museum of Natural History, Smithsonian Institution, Washington D.C. Specimens for those collections were captured by a variety of field techniques, narcotized with Cloral hydrate, fixed in formalin and stored in 70-80% alcohol. A total of 75 species have been identified from Cuban waters: Asteroidea (20 species) and Ophiuroidea (55 species).

  7. Phylogenomic analyses of Echinodermata support the sister groups of Asterozoa and Echinozoa.

    Science.gov (United States)

    Reich, Adrian; Dunn, Casey; Akasaka, Koji; Wessel, Gary

    2015-01-01

    Echinoderms (sea urchins, sea stars, brittle stars, sea lilies and sea cucumbers) are a group of diverse organisms, second in number within deuterostome species to only the chordates. Echinoderms serve as excellent model systems for developmental biology due to their diverse developmental mechanisms, tractable laboratory use, and close phylogenetic distance to chordates. In addition, echinoderms are very well represented in the fossil record, including some larval features, making echinoderms a valuable system for studying evolutionary development. The internal relationships of Echinodermata have not been consistently supported across phylogenetic analyses, however, and this has hindered the study of other aspects of their biology. In order to test echinoderm phylogenetic relationships, we sequenced 23 de novo transcriptomes from all five clades of echinoderms. Using multiple phylogenetic methods at a variety of sampling depths we have constructed a well-supported phylogenetic tree of Echinodermata, including support for the sister groups of Asterozoa (sea stars and brittle stars) and Echinozoa (sea urchins and sea cucumbers). These results will help inform developmental and evolutionary studies specifically in echinoderms and deuterostomes in general.

  8. Phylogenomic analyses of Echinodermata support the sister groups of Asterozoa and Echinozoa.

    Directory of Open Access Journals (Sweden)

    Adrian Reich

    Full Text Available Echinoderms (sea urchins, sea stars, brittle stars, sea lilies and sea cucumbers are a group of diverse organisms, second in number within deuterostome species to only the chordates. Echinoderms serve as excellent model systems for developmental biology due to their diverse developmental mechanisms, tractable laboratory use, and close phylogenetic distance to chordates. In addition, echinoderms are very well represented in the fossil record, including some larval features, making echinoderms a valuable system for studying evolutionary development. The internal relationships of Echinodermata have not been consistently supported across phylogenetic analyses, however, and this has hindered the study of other aspects of their biology. In order to test echinoderm phylogenetic relationships, we sequenced 23 de novo transcriptomes from all five clades of echinoderms. Using multiple phylogenetic methods at a variety of sampling depths we have constructed a well-supported phylogenetic tree of Echinodermata, including support for the sister groups of Asterozoa (sea stars and brittle stars and Echinozoa (sea urchins and sea cucumbers. These results will help inform developmental and evolutionary studies specifically in echinoderms and deuterostomes in general.

  9. Biology of Incidental Catch Sea Star Stellaster childreni Gray, 1840 (Echinodermata: Asteroidea), from Malaysian Borneo Exclusive Economic Zone

    OpenAIRE

    Hassan, Ruhana; Lee, Suet Yee; Morni, Wan Zabidii Wan

    2017-01-01

    Sea star (class Asteroidea, phylum Echinodermata) is one of the most successful marine organisms inhabiting a wide range of habitats. As one of the key stone species, sea stars are responsible for maintaining much of the local diversity of species within certain communities. Malaysian Exclusive Economic Zone (EEZ) Resource Survey had been carried out from 16th Aug to 6th Nov 2015 and one of the invertebrate by-catch organisms is sea star Stellaster childreni Gray, 1840. This study documents m...

  10. Higher ribosomal RNA substitution rates in Bacillariophyceae and Dasycladales than in Mollusca, Echinodermata, and Actinistia-Tetrapoda.

    Science.gov (United States)

    Sorhannus, U

    1996-09-01

    Molecular evolutionary rates within two protistan and three metazoan taxa were estimated using divergence times derived from fossil records. The results indicate that the small-subunit rRNA sequences within Dasycladales (Chlorophyta) and Bacillariophyceae evolved at a rate approximately two to three times faster than that estimated within Echinodermata, Mollusca, and Actinistia-Tetrapoda. It was concluded that this twofold discrepancy demonstrates actual taxonomic differences in the fixation rate of mutations in the small-subunit rRNA.

  11. Crinoids of the stalked family Hyocrinidae (Echinodermata) collected by the USNS Eltanin in the Southern Ocean.

    Science.gov (United States)

    Roux, Michel

    2015-07-27

    Rare species only known from one or a few specimens, mainly collected from abyssal and hadal zones in the Southern Ocean are represented in a collection of stalked crinoids attributed to the family Hyocrinidae (Crinoidea, Echinodermata). The species studied here include Belyaevicrinus latipinnulus Mironov & Sorokina, 1998, Feracrinus heinzelleri Bohn, 2012, Ptilocrinus brucei Vaney, 1908 and Thalassocrinus clausus Mironov & Sorokina, 1998. This collection, mainly collected during the 1960s USNS Eltanin cruises, is housed at the Smithsonian Institution National Museum of Natural History in Washington DC. A detailed study of this material using SEM observations of ossicle articular facets and pinnule architecture allows the emendation of species diagnoses, and a better description of intraspecific variation and of changes in characters through ontogeny. Geographical and depth range extension of species are reported. A gonad with submature ovocytes of 100-150 µm was exceptionally preserved at the base of a genital pinnule of P. brucei. This species likely has a lecithotrophic larval development.

  12. Primer registro de Heterocucumis godeffroyi(Semper, 1868 (Echinodermata: Holothuroidea en el mar peruano

    Directory of Open Access Journals (Sweden)

    Francisco Alonso Solís-Marín

    2013-06-01

    Full Text Available Se registra por primera vez para el Perú la especie de pepino de mar Heterocucumis godeffroyi(Semper, 1868 (Echinodermata: Holothuroidea. La especie fue recolectada a 19 m de profundidad en Pucusana, de-partamento de Lima. Este registro representa el límite más norteño de distribución de la especie reconocido hasta el momento. Material de referencia se encuentra depositado en la Colección de Zoología Acuática, del Laboratorio de Biología Marina, Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia, Lima, Perú.

  13. Ophiuroidea (Echinodermata: quatro novas ocorrências para o Brasil Ophiuroidea (Echinodermata: four new records for Brazil

    Directory of Open Access Journals (Sweden)

    Michela Borges

    2007-12-01

    Full Text Available Os ofiuróides aqui analisados são procedentes dos programas "Biodiversidade Bêntica Marinha no Estado de São Paulo" - BIOTA/FAPESP-Bentos Marinhos, "Avaliação do Potencial Sustentável dos Recursos Vivos da Zona Econômica Exclusiva" - REVIZEE/Score Sul-Bentos e "Utilização Racional dos Ecossistemas Costeiros da Região Tropical Brasileira: Estado de São Paulo" - INTEGRADO/Subprojeto Bentos. As amostras analisadas foram coletadas nas regiões da plataforma e talude continental do Sudeste e Sul brasileiros, em profundidades entre 10 e 800 m. São aqui descritas e ilustradas quatro espécies de Ophiuroidea, as quais representam novos registros de ocorrência para o Brasil, duas da família Ophiuridae, uma de Amphiuridae e uma de Ophiochitonidae. Este é também o primeiro registro desta última família para o Brasil. Somente Amphiodia trychna (Amphiuridae foi amostrada na região da plataforma interna (profundidade The ophiuroids were collected during the Programs "Biodiversidade Bêntica Marinha no Estado de São Paulo" - BIOTA/FAPESP-Marine Benthos, "Avaliação do Potencial Sustentável dos Recursos Vivos da Zona Econômica Exclusiva" - REVIZEE/Score South - Benthos and "Utilização Racional dos Ecossistemas Costeiros da Região Tropical Brasileira: Estado de São Paulo" - INTEGRADO/Subproject Benthos. Samples were obtained from the continental shelf and slope off southeast and south Brazil, between 10 and 800 m. Four species of the Ophiuroidea are described and they are new records for Brazil. Two species belong to the family Ophiuridae, and the others belong to Amphiuridae and Ophiochitonidae. The family Ophiochitonidae is recorded for the first time in Brazil. Amphiodia trychna (Amphiuridae was sampled in the inner continental shelf (depth < 50 m. The other three species were collected deeper (between 314 and 808 m.

  14. Primeiro registro de Goniasteridae (Echinodermata, Asteroidea) no cretáceo do Brasil: turoniano da Bacia Potiguar

    OpenAIRE

    Manso, Cynthia Lara de Castro

    2006-01-01

    Um pequeno braço de Goniasteridae (Echinodermata: Asteroidea) tentativamente atribuída ao gênero Crateraster Spencer, representa o primeiro registro Fóssil da família no Brasil. Ela foi coletada em sedimentos carbonáticos turonianos da Bacia Potiguar, Rio Grande do Norte. Essa estrela do mar, diferente da maioria dos Goniasteridae atuais encontrados em águas mais profundas ou mais frias, provavelmente viveu em um ambiente costeiro raso e de águas mornas._______________________________________...

  15. Tres nuevos registros de asteroideos (Echinodermata: Asteroidea de Perú

    Directory of Open Access Journals (Sweden)

    Yuri Hooker

    2012-02-01

    Full Text Available En el presente trabajo se registran 3 nuevos asteroideos (Echinodermata: Asteroidea de aguas someras (4 - >50 m para el Perú: Astropecten regalis Gray, 1840, Paulia horrida Gray 1840 y Meyenaster gelatinosus (Meyen, 1834. Astropecten regalis se conocía desde el Golfo de California hasta Panamá, en el presente trabajo, se amplía su distribución hasta Máncora, Perú. La distribución geográfica de Paulia horrida era conocida desde Baja California, hasta Isla Cocos, Costa Rica, en este estudio se amplía su distribución geográfica hasta Punta Sal, Perú. A Meyenaster gelatinosus se le conocía solo de Chile, en el presente trabajo se registra y confirma su presencia en el Perú, ampliando su distribución norte hasta San Juan de Marcona. Se proporciona información morfológica de las especies, características del hábitat y fotografías in situ y de los especímenes recién recolectados.

  16. Determination of toxic heavy metals in Echinodermata and Chordata species from South Korea.

    Science.gov (United States)

    Choi, Ji Yeon; Habte, Girum; Khan, Naeem; Nho, Eun Yeong; Hong, Joon Ho; Choi, Hoon; Park, Kyung Su; Kim, Kyong Su

    2014-01-01

    This study aimed at analysing concentrations of heavy metals including arsenic, lead, cadmium, aluminium and mercury in commonly consumed seafood species belonging to Echinodermata (Anthocidaris crassispina and Stichopus japonicus) and Chordata (Halocynthia roretzi and Styela plicata). The samples were digested by a microwave system and analysed for As, Cd and Pb by inductively coupled plasma mass spectrometer, for Al by inductively coupled plasma-optical emission spectrometer and Hg by Direct Mercury Analyser. The analytical method was validated by determining sensitivity, linearity, precision, spiking recoveries and analysis of the Standard Reference Material (SRM) NIST 1566-b, an Oyster Tissue. Results showed considerably higher accumulation of Al and As in analysed samples, compared to Pb and Cd, while Hg had the lowest contamination. On comparison, the obtained results with the recommended standards by the Food and Agriculture Organization, European Commission and Ministry of Food and Drug Safety of Korea, it was concluded that the analysed seafoods were safe and thus would not pose a threat to consumers.

  17. Antitropical distributions and species delimitation in a group of ophiocomid brittle stars (Echinodermata: Ophiuroidea: Ophiocomidae).

    Science.gov (United States)

    Naughton, K M; O'Hara, T D; Appleton, B; Cisternas, P A

    2014-09-01

    In this paper we examine the phylogeny and biogeography of the temperate genera of the Ophiocomidae (Echinodermata: Ophiuroidea) which have an interesting asymmetrical anti-tropical distribution, with two genera (Ophiocomina and Ophiopteris) previously considered to have a separate species in both the North and South hemispheres, and the third (Clarkcoma) diversifying in the southern Australian/New Zealand region. Our phylogeny, generated from one mitochondrial and two nuclear markers, revealed that Ophiopteris is sister to a mixed Ophiocomina/Clarkcoma clade. Ophiocomina was polyphyletic, with O. nigra and an undescribed species from the South Atlantic Ocean sister to a clade including Clarkcoma species and O. australis. The phylogeny also revealed a number of recently diverged lineages occurring within Clarkcoma, some of which are considered to be cryptic species due to the similarity in morphology combined with the apparent absence of interbreeding in a sympatric distribution, while the status of others is less certain. The phylogeny provides support for two transequatorial events in the group under study. A molecular clock analysis places both events in the middle to late Miocene. The analysis excludes a tectonic vicariance hypothesis for the antitropical distribution associated with the breakup of Pangaea and also excludes the hypothesis of more recent gene flow associated with Plio/Pleistocene glacial cycling. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. A NEW, EARLY CROWN-GROUP ASTEROID (ECHINODERMATA FROM THE NORIAN (TRIASSIC OF NORTHERN ITALY

    Directory of Open Access Journals (Sweden)

    DANIEL B. BLAKE

    2000-07-01

    Full Text Available Noriaster barberoi gen. et. sp. n. is based on a single specimen from the Calcare di Zorzino (Norian, Triassic of northern Italy. A member of the surviving Poraniidae (Valvatida; Echinodermata, N. barberoi is the oldest-known species assignable to a Jurassic and younger family and the first such species known from the Triassic. No Paleozoic species with close affinities with crown-group families has been recognized. Noriaster and the slightly older Triassic genus Trichasteropsis from the Muschelkalk of Germany together indicate that the diversification of crown-group asteroids was well underway at least by Middle and Late Triassic time. Phylogeny of crown-group asteroids is problematic because extant familial-level taxa are morphologically divergent, and they exhibit comparatively few uncontested characters that clearly indicate phylogenetic affinities and sequence. Familial assignment of Noriaster is supported by a new cladistic analysis. To the student of living asteroids, the appearance of a living Noriaster would be remarkable only because it would seem so commonplace. To the extent that form correlates with function, Noriaster suggests that modern asteroid life modes emerged quite promptly during the Mesozoic asteroid diversification. 

  19. Molecular phylogeny of the order Euryalida (Echinodermata: Ophiuroidea), based on mitochondrial and nuclear ribosomal genes.

    Science.gov (United States)

    Okanishi, Masanori; O'Hara, Timothy D; Fujita, Toshihiko

    2011-11-01

    The existing taxonomy of Euryalida, one of the two orders of the Ophiuroidea (Echinodermata), is uncertain and characterized by controversial delimitation of taxonomic ranks from genus to family-level. Their phylogeny was not studied in detail until now. We investigated a dataset of sequence from a mitochondrial gene (16S rRNA) and two nucleic genes (18S rRNA and 28S rRNA) for 49 euryalid ophiuroids and four outgroup species from the order Ophiurida. The monophyly of the order Euryalida was supported as was the monophyly of Asteronychidae, Gorgonocephalidae and an Asteroschematidae+Euryalidae clade. However, the group currently known as the Asteroschematidae was paraphyletic with respect to the Euryalidae. The Asteroschematidae+Euryalidae clade, which we recognise as an enlarged Euryalidae, contains three natural groups: the Asteroschematinae (Asteroschema and Ophiocreas), a new subfamily Astrocharinae (Astrocharis) and the Euryalinae with remaining genera. These subfamilies can be distinguished by internal ossicle morphology. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Reconstructing SALMFamide Neuropeptide Precursor Evolution in the Phylum Echinodermata: Ophiuroid and Crinoid Sequence Data Provide New Insights

    Science.gov (United States)

    Elphick, Maurice R.; Semmens, Dean C.; Blowes, Liisa M.; Levine, Judith; Lowe, Christopher J.; Arnone, Maria I.; Clark, Melody S.

    2015-01-01

    The SALMFamides are a family of neuropeptides that act as muscle relaxants in echinoderms. Analysis of genome/transcriptome sequence data from the sea urchin Strongylocentrotus purpuratus (Echinoidea), the sea cucumber Apostichopus japonicus (Holothuroidea), and the starfish Patiria miniata (Asteroidea) reveals that in each species there are two types of SALMFamide precursor: an L-type precursor comprising peptides with a C-terminal LxFamide-type motif and an F-type precursor solely or largely comprising peptides with a C-terminal FxFamide-type motif. Here, we have identified transcripts encoding SALMFamide precursors in the brittle star Ophionotus victoriae (Ophiuroidea) and the feather star Antedon mediterranea (Crinoidea). We have also identified SALMFamide precursors in other species belonging to each of the five echinoderm classes. As in S. purpuratus, A. japonicus, and P. miniata, in O. victoriae there is one L-type precursor and one F-type precursor. However, in A. mediterranea only a single SALMFamide precursor was found, comprising two peptides with a LxFamide-type motif, one with a FxFamide-type motif, five with a FxLamide-type motif, and four with a LxLamide-type motif. As crinoids are basal to the Echinozoa (Holothuroidea + Echinoidea) and Asterozoa (Asteroidea + Ophiuroidea) in echinoderm phylogeny, one model of SALMFamide precursor evolution would be that ancestrally there was a single SALMFamide gene encoding a variety of SALMFamides (as in crinoids), which duplicated in a common ancestor of the Echinozoa and Asterozoa and then specialized to encode L-type SALMFamides or F-type SALMFamides. Alternatively, a second SALMFamide precursor may remain to be discovered or may have been lost in crinoids. Further insights will be obtained if SALMFamide receptors are identified, which would provide a molecular basis for experimental analysis of the functional significance of the “cocktails” of SALMFamides that exist in echinoderms. PMID:25699014

  1. Reconstructing SALMFamide neuropeptide precursor evolution in the phylum Echinodermata: ophiuroid and crinoid sequence data provide new insights

    Directory of Open Access Journals (Sweden)

    Maurice R Elphick

    2015-02-01

    Full Text Available The SALMFamides are a family of neuropeptides that act as muscle relaxants in echinoderms. Analysis of genome/transcriptome sequence data from the sea urchin Strongylocentrotus purpuratus (Echinoidea, the sea cucumber Apostichopus japonicus (Holothuroidea and the starfish Patiria miniata (Asteroidea reveals that in each species there are two types of SALMFamide precursor: an L-type precursor comprising peptides with a C-terminal LxFamide-type motif and an F-type precursor solely or largely comprising peptides with a C-terminal FxFamide-type motif. Here we have identified transcripts encoding SALMFamide precursors in the brittle star Ophionotus victoriae (Ophiuroidea and the feather star Antedon mediterranea (Crinoidea. We have also identified SALMFamide precursors in other species belonging to each of the five echinoderm classes. As in S. purpuratus, A. japonicus and P. miniata, in O. victoriae there is one L-type precursor and one F-type precursor. However, in A. mediterranea only a single SALMFamide precursor was found, comprising two peptides with a LxFamide-type motif, one with a FxFamide-type motif, five with a FxLamide-type motif and four with a LxLamide-type motif. As crinoids are basal to the Echinozoa (Holothuroidea + Echinoidea and Asterozoa (Asteroidea + Ophiuroidea in echinoderm phylogeny, one model of SALMFamide precursor evolution would be that ancestrally there was a single SALMFamide gene encoding a variety of SALMFamides (as in crinoids, which duplicated in a common ancestor of the Echinozoa and Asterozoa and then specialised to encode L-type SALMFamides or F-type SALMFamides. Alternatively, a second SALMFamide precursor may remain to be discovered or may have been lost in crinoids. Further insights will be obtained if SALMFamide receptors are identified, which would provide a molecular basis for experimental analysis of the functional significance of the cocktails of SALMFamides that exist in echinoderms.

  2. Deep-sea echinoderm oxygen consumption rates and an interclass comparison of metabolic rates in Asteroidea, Crinoidea, Echinoidea, Holothuroidea and Ophiuroidea.

    Science.gov (United States)

    Hughes, Sarah Jane Murty; Ruhl, Henry A; Hawkins, Lawrence E; Hauton, Chris; Boorman, Ben; Billett, David S M

    2011-08-01

    Echinoderms are important components of deep-sea communities because of their abundance and the fact that their activities contribute to carbon cycling. Estimating the echinoderm contribution to food webs and carbon cycling is important to our understanding of the functioning of the deep-sea environment and how this may alter in the future as climatic changes take place. Metabolic rate data from deep-sea echinoderm species are, however, scarce. To obtain such data from abyssal echinoderms, a novel in situ respirometer system, the benthic incubation chamber system (BICS), was deployed by remotely operated vehicle (ROV) at depths ranging from 2200 to 3600 m. Oxygen consumption rates were obtained in situ from four species of abyssal echinoderm (Ophiuroidea and Holothuroidea). The design and operation of two versions of BICS are presented here, together with the in situ respirometry measurements. These results were then incorporated into a larger echinoderm metabolic rate data set, which included the metabolic rates of 84 echinoderm species from all five classes (Asteroidea, Crinoidea, Echinoidea, Holothuroidea and Ophiuroidea). The allometric scaling relationships between metabolic rate and body mass derived in this study for each echinoderm class were found to vary. Analysis of the data set indicated no change in echinoderm metabolic rate with depth (by class or phylum). The allometric scaling relationships presented here provide updated information for mass-dependent deep-sea echinoderm metabolic rate for use in ecosystem models, which will contribute to the study of both shallow water and deep-sea ecosystem functioning and biogeochemistry.

  3. Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.

    Science.gov (United States)

    Thabet, Rahma; Rouault, J-D; Ayadi, Habib; Leignel, Vincent

    2016-01-01

    The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. 13. Echinodermata

    NARCIS (Netherlands)

    Wanner, J.

    1931-01-01

    Eine Zusammenstellung der fossilen Echinodermen des ostindischen Archipels gibt heute selbstverständlich auch nicht annähernd ein getreues Bild von dem wirklichen Umfange der Echinodermenfaunen, welche in den uns zugänglichen Ablagerungen dieser ausgedehnten Inselwelt begraben sind. Dafür ist die

  5. Echinodermata: Euechinoidea

    African Journals Online (AJOL)

    A junior homonym was detected among fossil echinoid genera and the following replacement name is proposed: Ekerekeia nom. nov. for Farquharsonia Currie, 1927 (nec Collin, 1922). Accordingly, new combinations are herein proposed for the species currently included in this genus: Ekerekeia crenulata (Kier 1972) ...

  6. The phylogeny of extant starfish (Asteroidea: Echinodermata) including Xyloplax, based on comparative transcriptomics.

    Science.gov (United States)

    Linchangco, Gregorio V; Foltz, David W; Reid, Rob; Williams, John; Nodzak, Conor; Kerr, Alexander M; Miller, Allison K; Hunter, Rebecca; Wilson, Nerida G; Nielsen, William J; Mah, Christopher L; Rouse, Greg W; Wray, Gregory A; Janies, Daniel A

    2017-10-01

    Multi-locus phylogenetic studies of echinoderms based on Sanger and RNA-seq technologies and the fossil record have provided evidence for the Asterozoa-Echinozoa hypothesis. This hypothesis posits a sister relationship between asterozoan classes (Asteroidea and Ophiuroidea) and a similar relationship between echinozoan classes (Echinoidea and Holothuroidea). Despite this consensus around Asterozoa-Echinozoa, phylogenetic relationships within the class Asteroidea (sea stars or starfish) have been controversial for over a century. Open questions include relationships within asteroids and the status of the enigmatic taxon Xyloplax. Xyloplax is thought by some to represent a newly discovered sixth class of echinoderms - and by others to be an asteroid. To address these questions, we applied a novel workflow to a large RNA-seq dataset that encompassed a broad taxonomic and genomic sample. This study included 15 species sampled from all extant orders and 13 families, plus four ophiuroid species as an outgroup. To expand the taxonomic coverage, the study also incorporated five previously published transcriptomes and one previously published expressed sequence tags (EST) dataset. We developed and applied methods that used a range of alignment parameters with increasing permissiveness in terms of gap characters present within an alignment. This procedure facilitated the selection of phylogenomic data subsets from large amounts of transcriptome data. The results included 19 nested data subsets that ranged from 37 to 4,281loci. Tree searches on all data subsets reconstructed Xyloplax as a velatid asteroid rather than a new class. This result implies that asteroid morphology remains labile well beyond the establishment of the body plan of the group. In the phylogenetic tree with the highest average asteroid nodal support several monophyletic groups were recovered. In this tree, Forcipulatida and Velatida are monophyletic and form a clade that includes Brisingida as sister to

  7. Computational Fluid Dynamics Analysis of the Fossil Crinoid Encrinus liliiformis (Echinodermata: Crinoidea.

    Directory of Open Access Journals (Sweden)

    Janina F Dynowski

    Full Text Available Crinoids, members of the phylum Echinodermata, are passive suspension feeders and catch plankton without producing an active feeding current. Today, the stalked forms are known only from deep water habitats, where flow conditions are rather constant and feeding velocities relatively low. For feeding, they form a characteristic parabolic filtration fan with their arms recurved backwards into the current. The fossil record, in contrast, provides a large number of stalked crinoids that lived in shallow water settings, with more rapidly changing flow velocities and directions compared to the deep sea habitat of extant crinoids. In addition, some of the fossil representatives were possibly not as flexible as today's crinoids and for those forms alternative feeding positions were assumed. One of these fossil crinoids is Encrinus liliiformis, which lived during the middle Triassic Muschelkalk in Central Europe. The presented project investigates different feeding postures using Computational Fluid Dynamics to analyze flow patterns forming around the crown of E. liliiformis, including experimental validation by Particle Image Velocimetry. The study comprises the analysis of different flow directions, velocities, as well as crown orientations. Results show that inflow from lateral and oral leads to direct transport of plankton particles into the crown and onto the oral surface. With current coming from the "rear" (aboral side of the crinoid, the conical opening of the crown produces a backward oriented flow in its wake that transports particles into the crown. The results suggest that a conical feeding position may have been less dependent on stable flow conditions compared to the parabolic filtration fan. It is thus assumed that the conical feeding posture of E. liliiformis was suitable for feeding under dynamically changing flow conditions typical for the shallow marine setting of the Upper Muschelkalk.

  8. Computational Fluid Dynamics Analysis of the Fossil Crinoid Encrinus liliiformis (Echinodermata: Crinoidea).

    Science.gov (United States)

    Dynowski, Janina F; Nebelsick, James H; Klein, Adrian; Roth-Nebelsick, Anita

    2016-01-01

    Crinoids, members of the phylum Echinodermata, are passive suspension feeders and catch plankton without producing an active feeding current. Today, the stalked forms are known only from deep water habitats, where flow conditions are rather constant and feeding velocities relatively low. For feeding, they form a characteristic parabolic filtration fan with their arms recurved backwards into the current. The fossil record, in contrast, provides a large number of stalked crinoids that lived in shallow water settings, with more rapidly changing flow velocities and directions compared to the deep sea habitat of extant crinoids. In addition, some of the fossil representatives were possibly not as flexible as today's crinoids and for those forms alternative feeding positions were assumed. One of these fossil crinoids is Encrinus liliiformis, which lived during the middle Triassic Muschelkalk in Central Europe. The presented project investigates different feeding postures using Computational Fluid Dynamics to analyze flow patterns forming around the crown of E. liliiformis, including experimental validation by Particle Image Velocimetry. The study comprises the analysis of different flow directions, velocities, as well as crown orientations. Results show that inflow from lateral and oral leads to direct transport of plankton particles into the crown and onto the oral surface. With current coming from the "rear" (aboral) side of the crinoid, the conical opening of the crown produces a backward oriented flow in its wake that transports particles into the crown. The results suggest that a conical feeding position may have been less dependent on stable flow conditions compared to the parabolic filtration fan. It is thus assumed that the conical feeding posture of E. liliiformis was suitable for feeding under dynamically changing flow conditions typical for the shallow marine setting of the Upper Muschelkalk.

  9. Starfish (Asteroidea, Echinodermata) from the Faroe Islands; spatial distribution and abundance

    Science.gov (United States)

    Ringvold, H.; Andersen, T.

    2016-01-01

    "Marine benthic fauna of the Faroe Islands" (BIOFAR) is a large programme with a focus on collecting invertebrate fauna from the Faroes (62°N and 7°W). Cruises were undertaken from 1987 to 1990, and starfish (Asteroidea, Echinodermata) collected during this time were analysed. Asteroidea were sampled at ~50% of all BIOFAR stations. A Detritus sledge and a Triangular dredge proved to be the most efficient equipment, collecting over 60% of the specimens. In total 2473 specimens were collected from 20 to 1500 m depth, including 41 species from 17 families and 31 genera. Henricia pertusa (O. F. Müller, 1776) group, Pontaster tenuispinus (Düben & Koren, 1846), and Leptychaster arcticus (M. Sars, 1851) showed highest relative abundance. Maximum species diversity was found at 500-700 m depth, which coincides with the transition zone of water masses (North Icelandic Winter Water and Arctic Intermediate Water (NI/AI)) at approximately 400-600 m depth. 63% of the species were recorded at an average-weighted depth above 600 m. Two different ordination methods (detrended correspondence analysis (DCA) and nonmetric multidimensional scaling (NMDS)) gave highly consistent representations of the community structure gradients. The first ordination axis scores did not show significant relationships with any environmental variable. Biological covariates like the presence of Lophelia corals were not significantly related to ordination scores on any axis. The second ordination axis scores were significantly correlated with depth. Temperature and salinity were highly correlated (r=0.90), and both negatively correlated with depth (r=-0.69 and r=-0.57, respectively).

  10. Abyssal fauna of the UK-1 polymetallic nodule exploration claim, Clarion-Clipperton Zone, central Pacific Ocean: Echinodermata.

    Science.gov (United States)

    Glover, Adrian G; Wiklund, Helena; Rabone, Muriel; Amon, Diva J; Smith, Craig R; O'Hara, Tim; Mah, Christopher L; Dahlgren, Thomas G

    2016-01-01

    We present data from a DNA taxonomy register of the abyssal benthic Echinodermata collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise 'AB01' to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration claim 'UK-1' in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. Morphological and genetic data are presented for 17 species (4 Asteroidea, 4 Crinoidea, 2 Holothuroidea and 7 Ophiuroidea) identified by a combination of morphological and genetic data. No taxa matched previously published genetic sequences, but 8 taxa could be assigned to previously-described species based on morphology, although here we have used a precautionary approach in taxon assignments to avoid over-estimating species ranges. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections.

  11. Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Echinodermata.

    Science.gov (United States)

    Amon, Diva J; Ziegler, Amanda F; Kremenetskaia, Antonina; Mah, Christopher L; Mooi, Rich; O'Hara, Tim; Pawson, David L; Roux, Michel; Smith, Craig R

    2017-01-01

    There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite being the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. In order to predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to these research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle, the megafauna within the UKSRL exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal echinoderm megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 62 distinct morphospecies (13 Asteroidea, 5 Crinoidea, 9 Echinoidea, 29 Holothuroidea and 6 Ophiuroidea) identified mostly by imagery but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat.

  12. Megafauna of the UKSRL exploration contract area and eastern Clarion-Clipperton Zone in the Pacific Ocean: Echinodermata

    Science.gov (United States)

    Ziegler, Amanda F; Kremenetskaia, Antonina; Mah, Christopher L; Mooi, Rich; O'Hara, Tim; Pawson, David L; Roux, Michel; Smith, Craig R

    2017-01-01

    Abstract Background There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite being the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. In order to predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to these research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. New information Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle, the megafauna within the UKSRL exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal echinoderm megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 62 distinct morphospecies (13 Asteroidea, 5 Crinoidea, 9 Echinoidea, 29 Holothuroidea and 6 Ophiuroidea) identified mostly by imagery but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat. PMID:28765722

  13. Remarks on Echinodermata from the South Central Mediterranean Sea based upon collections made during the MARCOS cruise (10 to 20th April, 2007

    Directory of Open Access Journals (Sweden)

    C. MIFSUD

    2009-12-01

    Full Text Available The MARCOS cruise, which took place in the South Central Mediterranean Sea on board the RV ‘Urania’, resulted in the collection of 27 species of Echinodermata from shallow to bathyal depths, many from around Malta (the Fisheries Management Zone. The fauna is represented by common to rare taxa already reported from the Mediterranean with the exception of the amphi-Atlantic ophiuroid Ophiotreta valenciennesi rufescens (Koehler, 1896, recorded from the Mediterranean Basin for the first time. Odontaster mediterraneus (von Marenzeller, 1893 and Luidia sarsi Lutken, 1858 are also first records for the Maltese Islands.

  14. African Zoology - Vol 26, No 4 (1991)

    African Journals Online (AJOL)

    New southern geographical records of intertidal sea urchins (Echinodermata: Echinoidea), with notes on abundance · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. D.J. Marshall, A.N. Hodgson, R.A. Pretorius, 204-205 ...

  15. Biology of Incidental Catch Sea Star Stellaster childreni Gray, 1840 (Echinodermata: Asteroidea, from Malaysian Borneo Exclusive Economic Zone

    Directory of Open Access Journals (Sweden)

    Ruhana Hassan

    2017-01-01

    Full Text Available Sea star (class Asteroidea, phylum Echinodermata is one of the most successful marine organisms inhabiting a wide range of habitats. As one of the key stone species, sea stars are responsible for maintaining much of the local diversity of species within certain communities. Malaysian Exclusive Economic Zone (EEZ Resource Survey had been carried out from 16th Aug to 6th Nov 2015 and one of the invertebrate by-catch organisms is sea star Stellaster childreni Gray, 1840. This study documents morphological characters and diet of the sea star, besides providing brief descriptions of the habitats based on particle size analysis and vessel log data sheet. A total of 217 individuals had been examined throughout this study. Fragments of flora and fauna were found in the gut including Mollusca (gastropod, bivalves, and scaphopods, sponge seagrass, and seaweed as well as benthic Foraminifera. Stellaster childreni were found at depth of 45 m to 185 m in the South China Sea off Sarawak Malaysia, with various sea bottom substrata. Approximately 41% of S. childreni were found at a mixture of sandy and muddy substratum, followed by mixture of sandy and coral (19.3%, muddy substratum (17.5%, coral substratum (11.5%, and sandy areas (10.6%. The widely distributed sea star on different types of sea beds suggested healthy deep sea ecosystem; thus Malaysia should explore further potential fisheries resources in the EEZ off Sarawak coast.

  16. A new species of brooding Psolidae (Echinodermata: Holothuroidea) from deep-sea off Argentina, Southwestern Atlantic Ocean

    Science.gov (United States)

    Martinez, Mariano I.; Penchaszadeh, Pablo E.

    2017-12-01

    This paper describes a new species of Psolus (Holothuroidea, Echinodermata), P. lawrencei sp. nov., (19 specimens) found in the deep sea (308-1398 m) in the Southwestern Atlantic Ocean (SWAO) (around 38°S-54°W) with brooders (up to 3.15 mm) in the tentacles of females and a penis-like genital papilla on males. The presence of dorsal scales, the concave shape of the ossicles with a bridge, the distribution of podia on the dorsal side and the absence of large and conspicuous oral and anal valves are unique for this species. Furthermore, this is the first species of this genus found outside Antarctica that broods between its tentacles. The paper also reviews the reproductive, brooding development and morphological characteristics of P. lawrencei sp. nov. and compares them with those of several members of the family Psolidae. Finally, a possible connectivity between the deep-sea populations in the SWAO and in Antarctica is considered based on the appearance of a similar reproductive pattern in populations found in both areas, which suggests a past or present connection between these regions.

  17. Sympatric cryptic species in the crinoid genus Cenolia (Echinodermata: Crinoidea: Comasteridae) delineated by sequence and microsatellite markers.

    Science.gov (United States)

    Naughton, K M; O'Hara, T D; Appleton, B; Gardner, M G

    2014-09-01

    The marine species of the southern coast of Australia have not been well studied with regard to molecular connectivity. Cryptic species are expected to be prevalent on this coastline. Here, we investigate the crinoid genus Cenolia (Echinodermata: Crinoidea: Comasteridae) using molecular methods to elucidate cryptic species and phylogenetic relationships. The genus Cenolia dominates the southern Australian crinoid fauna in shallow waters. Few studies have examined crinoids for cryptic species at a molecular level and these have been predominantly based on mitochondrial data. We employ the nuclear markers 28S rRNA and ITS-2 in addition to the mitochondrial COI. Six divergent mitochondrial clades were identified. Gene flow between confirmed clades was subsequently examined by the use of six novel microsatellite markers, showing that sympatric taxa with low mtDNA divergences (1.7% K2P) were not interbreeding in the wild. The type specimens of Cenolia benhami and C. spanoschistum were examined, as well as all six divergent clades. Morphological characters dividing taxa were refined. Due to comb pinnule morphology, the New Zealand species benhami was determined to belong to the genus Oxycomanthus (nov. comb.). Three new species of Cenolia (including the Australian "benhami") require description. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Biology of Incidental Catch Sea StarStellaster childreniGray, 1840 (Echinodermata: Asteroidea), from Malaysian Borneo Exclusive Economic Zone.

    Science.gov (United States)

    Hassan, Ruhana; Lee, Suet Yee; Morni, Wan Zabidii Wan

    2017-01-01

    Sea star (class Asteroidea, phylum Echinodermata) is one of the most successful marine organisms inhabiting a wide range of habitats. As one of the key stone species, sea stars are responsible for maintaining much of the local diversity of species within certain communities. Malaysian Exclusive Economic Zone (EEZ) Resource Survey had been carried out from 16th Aug to 6th Nov 2015 and one of the invertebrate by-catch organisms is sea star Stellaster childreni Gray, 1840. This study documents morphological characters and diet of the sea star, besides providing brief descriptions of the habitats based on particle size analysis and vessel log data sheet. A total of 217 individuals had been examined throughout this study. Fragments of flora and fauna were found in the gut including Mollusca (gastropod, bivalves, and scaphopods), sponge seagrass, and seaweed as well as benthic Foraminifera. Stellaster childreni were found at depth of 45 m to 185 m in the South China Sea off Sarawak Malaysia, with various sea bottom substrata. Approximately 41% of S. childreni were found at a mixture of sandy and muddy substratum, followed by mixture of sandy and coral (19.3%), muddy substratum (17.5%), coral substratum (11.5%), and sandy areas (10.6%). The widely distributed sea star on different types of sea beds suggested healthy deep sea ecosystem; thus Malaysia should explore further potential fisheries resources in the EEZ off Sarawak coast.

  19. Abyssal fauna of the UK-1 polymetallic nodule exploration claim, Clarion-Clipperton Zone, central Pacific Ocean: Echinodermata

    Science.gov (United States)

    Glover, Adrian G; Wiklund, Helena; Rabone, Muriel; Amon, Diva J; Smith, Craig R; O'Hara, Tim; Mah, Christopher L

    2016-01-01

    Abstract We present data from a DNA taxonomy register of the abyssal benthic Echinodermata collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise ‘AB01’ to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration claim ‘UK-1’ in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. Morphological and genetic data are presented for 17 species (4 Asteroidea, 4 Crinoidea, 2 Holothuroidea and 7 Ophiuroidea) identified by a combination of morphological and genetic data. No taxa matched previously published genetic sequences, but 8 taxa could be assigned to previously-described species based on morphology, although here we have used a precautionary approach in taxon assignments to avoid over-estimating species ranges. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections. PMID:26929713

  20. Ophionereis reticulata (Echinodermata, Ophiuroidea Regeneração dos braços em duas populações de Ophionereis reticulata (Echinodermata, Ophiuroidea

    Directory of Open Access Journals (Sweden)

    Leonardo Q. Yokoyama

    2010-06-01

    Full Text Available This study compared the arm regeneration frequencies in two different populations of Ophionereis reticulata (Say, 1825 in São Sebastião, Southeast Brazil and observed arm regeneration between age classes (juvenile and adults and sexes (male and female. From the 1,170 individuals sampled, 1,089 (92.2% showed signs of arm regeneration. The relative frequencies of regenerating arms in the two areas were not different (Baleeiro Isthmus: 91.3% and Grande Beach: 99.5%. Both areas also presented similar values for the number of arms regenerating/individual and in the frequency of regenerating individuals. The major part of the regenerating scars was concentrated in the distal portion of the arm. Sub-lethal predation is most likely the cause to the high rates of arm regeneration in O. reticulata. There was no significant differences in the regeneration rates between females (3.57 ± 1.36 arms regenerating/individual and males (3.47 ± 1.42.Este estudo comparou as frequências de regeneração dos braços de duas populações de Ophionereis reticulata (Say, 1825, de São Sebastião, sudeste do Brasil. Além disso, foram observadas diferenças nas frequências de regeneração entre classes etárias (juvenis e adultos e entre machos e fêmeas. Dos 1.170 indivíduos coletados, 1.089 (92,2% mostraram sinais de regeneração nos braços. A frequência relativa de braços em regeneração entre as duas áreas não diferiu significativamente (Istmo do Baleeiro: 91,3% e Praia Grande: 99,5%. Ambas as áreas apresentaram valores semelhantes no número de braços regenerando/indivíduo e na frequência de indivíduos em regeneração. A maior parte das marcas de regeneração concentraram-se na porção distal dos braços, o que indica a influência de predação subletal como a causa principal da regeneração em O. reticulata. Além disso, não houve diferença significativa nos índices de regeneração entre fêmeas (3,57 ± 1,36 braços regenerando

  1. An ultrasensitive sandwich-type electrochemical immunosensor based on the signal amplification strategy of echinoidea-shaped Au@Ag-Cu2O nanoparticles for prostate specific antigen detection.

    Science.gov (United States)

    Yang, Yuying; Yan, Qin; Liu, Qing; Li, Yongpeng; Liu, Hui; Wang, Ping; Chen, Lei; Zhang, Daopeng; Li, Yueyun; Dong, Yunhui

    2018-01-15

    Highly sensitive determination of tumor markers plays an important role in early diagnosis of cancer. Herein, a novel and ultrasensitive sandwich-type electrochemical immunosensor was fabricated for quantitative detection of prostate specific antigen (PSA). In this process, gold nanoparticles functionalized nitrogen-doped graphene quantum dots (Au@N-GQDs) was synthesized through a simple and green hydrothermal procedure to enhance conductivity, specific electrode surface area and quantity of immobilized primary antibodies (Ab 1 ). Subsequently, the prepared echinoidea-shaped nanocomposites (Au@Ag-Cu 2 O) composed of Au@Ag core-shell nanoparticles and disordered cuprous oxide were prepared successfully to label the secondary antibodies (Ab 2 ), which convened the advantages of good biocompatibility and high specific surface area. Because of the synergetic effect present in Au, Ag and Cu 2 O, the novel nanocomposites exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide (H 2 O 2 ) for the amplified detection of PSA. Therefore, the as-proposed immunosensor for the detection of PSA possessed wide dynamic range from 0.01pg/mL to 100ng/mL with a low detection limit of 0.003pg/mL (S/N = 3). Furthermore, this sandwich-type immunosensor revealed high sensitivity, high selectivity and long-term stability, which had promising application in bioassay analysis. Copyright © 2017. Published by Elsevier B.V.

  2. Discoplana malagasensis sp. nov., a new turbellarian (Platyhelminthes: Polycladida: Leptoplanidae) symbiotic in an ophiuroid (Echinodermata), with a cladistic analysis of the Discoplana/Euplana species.

    Science.gov (United States)

    Doignon, Gilles; Artois, Tom; Deheyn, Dimitri

    2003-03-01

    A new species of polyclad flatworm from Papua New Guinea is described. It is found symbiotic in the ophiuroid Ophiothrix purpurea von Martens, 1867 (Echinodermata: Ophiuroidea). Apparently it belongs to the taxon Discoplana Bock, 1913 and can be distinguished from the six previously described Discoplana species by its very short ejaculatory duct and a penial papilla covered with a penial sheath, but without any true sclerotised structures such as a stylet or spines. The cladistic analysis of the Discoplana/ Euplana species, based on morphological features and including two outgroups, reveals that all species of Discoplana, except D. pacificola, form a monophyletic taxon, that is not a synonym of Euplana Girard, 1893. Therefore the name Discoplana is conserved and the new species will be described as Discoplana malagasensis sp. nov. A key for the Discoplana/Euplana group is provided. In this key the biogeographical distribution and possible synonyms are given.

  3. Molecular phylogeny based on increased number of species and genes revealed more robust family-level systematics of the order Euryalida (Echinodermata: Ophiuroidea).

    Science.gov (United States)

    Okanishi, Masanori; Fujita, Toshihiko

    2013-12-01

    Previous molecular analysis of the order Euryalida (Echinodermata: Ophiuroidea), has identified three monophyletic families, the Euryalidae, Asteronychidae and Gorgonocephalidae. However, family-level relationships have remained unresolved due to inadequate taxon sampling and insufficient molecular markers. Here, we present a family-level revision of the Euryalida based on sequences from mitochondrial genes (16S rRNA and COI) and a nuclear gene (18S rRNA) from 83 euryalid ophiuroids. The monophyly of the three families, Euryalidae, Asteronychidae and Gorgonocephalidae is confirmed. The Euryalidae and Asteronychidae+Gorgonocephalidae are assigned to superfamilies, the Euryalidea and the Gorgonocephalidea, respectively. Three subclades within the family Gorgonocephalidae are identified and assigned to three subfamilies; Astrotominae includes Astrocrius, Astrohamma and Astrotoma, Astrothamninae (subfamily nov.) includes Astrothamnus and Astrothrombus with Gorgonocephalinae including the remaining genera. Morphological characters are consistent with the newly recognised superfamilies and subfamilies. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Echinodermata: Holothuroidea: Dendrochirotida

    African Journals Online (AJOL)

    Zoology Department, University of Durban-Westville, Private Bag X54001. Durban. 4000 South Africa thandar@pixie.udw.ac.za. Received 13 ... remarkable similarity in the body wall deposits of genera currently classified in two separate subfamilies chal- lenges the use of the calcareous ring to separate subfamilies, since it ...

  5. Depth-related distribution and abundance of seastars (Echinodermata: Asteroidea) in the Porcupine Seabight and Porcupine Abyssal Plain, N.E. Atlantic

    Science.gov (United States)

    Howell, Kerry L.; Billett, David S. M.; Tyler, Paul A.

    2002-10-01

    The depth-related distribution of seastar (Echinodermata: Asteroidea) species between 150 and 4950 m in the Porcupine Seabight and Porcupine Abyssal Plain is described. 47 species of asteroid were identified from ˜14,000 individuals collected. The bathymetric range of each species is recorded. What are considered quantitative data, from an acoustically monitored epibenthic sledge and supplementary data from otter trawls, are used to display the relative abundance of individuals within their bathymetric range. Asteroid species are found to have very narrow centres of distribution in which they are abundant, despite much wider total adult depth ranges. Centres of distribution may be skewed. This might result from competition for resources or be related to the occurrence of favourable habitats at particular depths. The bathymetric distributions of the juveniles of some species extend outside the adult depth ranges. There is a distinct pattern of zonation with two major regions of faunal change and six distinct zones. An upper slope zone ranges from 150 to ˜700 m depth, an upper bathyal zone between 700 and 1100 m, a mid-bathyal zone from 1100 to1700 m and a lower bathyal zone between 1700 and 2500 m. Below 2500 m the lower continental slope and continental rise have a characteristic asteroid fauna. The abyssal zone starts at about 2800 m. Regions of major faunal change are identified at the boundaries of both upper and mid-bathyal zones and at the transition of bathyal to abyssal fauna. Diversity is greatest at ˜1800 m, decreasing with depth to ˜2600 m before increasing again to high levels at ˜4700 m.

  6. from Pyura stolollifera (Echinodermata, Ascidiacea)

    African Journals Online (AJOL)

    1994-05-05

    May 5, 1994 ... originating from the distal end of second segment. The tcrrninal segment modified into a sharp, curved and heavily sclerotized hook. Maxilla (Figure Ie) three segmented. Basal segment bulbous, second and third much reduced in diameter. The segments bear numbers of plumose selae of varying lengths;.

  7. A serendipidade na medicina e na anestesiologia

    OpenAIRE

    Vale, Nilton Bezerra do; Delfino, José; Vale, Lúcio Flávio Bezerra do

    2005-01-01

    JUSTIFICATIVA E OBJETIVOS: Neste trabalho foram examinados mais de uma centena dos mais felizes acoplamentos de uma mente brilhante com a sorte benfazeja (serendipidade), através da releitura das mais relevantes histórias sobre invenções e descobertas relacionadas à ciência (n = 46), à Medicina (n = 46) e à Anestesiologia (n = 16). CONTEÚDO: Conceito de serendipidade; exemplos célebres de serendipidade em Ciência e Tecnologia; serendipidade na pesquisa e prática médicas; serendipidade na Anes...

  8. NA60 Status Report

    CERN Document Server

    Usai, G

    2010-01-01

    This report shortly summarizes the main results obtained from the analysis of the NA60 data during 2010, perspectives for the analysis activity during 2011 and the requests to CERN following from them. In addition, renewed interest is expressed for a possible continuation of NA60, including future running at lower SPS energies.

  9. At NA2

    CERN Multimedia

    1977-01-01

    One of the NA2 calorimeter sections is moved in. The NA2 calorimeter was divided in two halves, to the left and the right of the beam, each half consisting of sheets of passive high Z material interleaved with blades of plastic scintillators. The photo shows on the right, the upstream 'electron' module with eleven lead plates for a total radiation length of 20.

  10. Polarization dependence of Na* + Na* associative ionization revisited

    NARCIS (Netherlands)

    Meijer, H.A.J.; Meulen, H.P. v.d.; Morgenstern, R.; Hertel, I.V.; Meyer, E.; Witte, R.

    1986-01-01

    The dependence of the associative ionization process Na 3 2P3/2 + Na 3 2P3/2 → Na2+ + e- on the polarization of the laser light used for Na excitation was independently investigated in Utrecht and Berlin. The purpose of this paper is to clarify discrepancies between two other earlier experimental

  11. Letramento na contemporaneidade

    OpenAIRE

    Kleiman, Angela B.

    2014-01-01

    Neste trabalho examino a relação entre letramento e contemporaneidade, tomando como base para a discussão o letramento no mundo escolar e sua relação com os letramentos de outras instituições do mundo contemporâneo, a fim de determinar as relações entre as finalidades contemporâneas da leitura e da escrita (em outras palavras, o que significa ser letrado na contemporaneidade) e as práticas mobilizadas e as atividades realizadas na escola para atingir essas finalidades. Através de diversos exe...

  12. Nietzsche na moda

    OpenAIRE

    José,João

    2016-01-01

    Resumo Ao resgatar o filósofo alemão do esquecimento, Stefan Zweig seria o principal responsável pela atual "voga Nietzsche". A edição brasileira de seu livro em 1931 e o artigo "L'actualité de Nietzsche", publicado anonimamente na França em 1933, atestariam o crescente interesse pelo autor de Zaratustra . A presença de Nietzsche na cena contemporânea, todavia, dever-se-ia não somente aos ensaios de outros estudiosos como Salomé (1893), Bertram (1918), Andler (1920) e Walz (1932), mas a um fe...

  13. Riso na epilepsia

    Directory of Open Access Journals (Sweden)

    Edymar Jardim

    1967-06-01

    Full Text Available São estudados três casos de síndrome convulsiva temporal, com manifestações concomitantes de riso na sua fase inicial. As características principais foram a imotivação e á incoercibilidade do riso. Esses sintomas desapareceram com o uso de anticonvulsivantes.

  14. Biotecnologia na agricultura

    Directory of Open Access Journals (Sweden)

    Helaine Carrer

    2010-01-01

    Full Text Available A expectativa de o crescimento populacional atingir 9 bilhões de habitantes em 2050 em adição às questões da sustentabilidade e do aquecimento global nos desafiam a aumentar a oferta de alimentos. Uma metodologia alternativa que contribua para a redução do impacto desse cenário envolve a biotecnologia, que, nas últimas décadas, trouxe marcantes oportunidades tecnológicas na agricultura, resultando em relevante desenvolvimento na obtenção de novas variedades de plantas, na melhoria da qualidade de diversos alimentos e atualmente também na bioenergia. As técnicas biotecnológicas envolvendo os marcadores moleculares, a genômica e a transformação genética estão transformando a agricultura e são discutidas neste artigo.The expected population growth to reach 9 billion by 2050 in addition to issues of sustainability and global warming challenges us to increase the supply of food. An alternative approach to help reducing the impact of this scenario involves biotechnology which in recent decades has brought remarkable technological opportunities in the agriculture that resulted in relevant development in obtaining new plant varieties, improved quality of different foods, and now also in bioenergy. The biotechnology techniques involving molecular markers, genomics and genetic transformation are transforming agriculture and will be discussed in this article.

  15. Hidroma subdural na fossa posterior

    Directory of Open Access Journals (Sweden)

    José Carlos Vasques

    1970-03-01

    Full Text Available Os autores relatam um caso de hidroma subdural na fossa craniana posterior conseqüente a traumatismo na região occipital. O paciente foi operado com pleno sucesso. A raridade da localização de hidroma na fossa posterior é salientada, sendo discutidos os possíveis mecanismos etio-patogênicos.

  16. A epilepsia na neurocisticercose

    Directory of Open Access Journals (Sweden)

    Luís Marques-Assis

    1972-12-01

    Full Text Available Foram estudados 131 casos de epilepsia com etiologia cisticercótica comprovada. A idade variou de 2 a 68 anos; 75 pacientes eram de sexo masculino e 56 de sexo feminino; 117 eram brancos, 10 pardos, três pretos e um amarelo. A idade de início da doença predominou na primeira década. O estudo foi feito em relação ao tipo de epilepsia, ao tempo decorrido após a primeira crise, à freqüência das crises e ao eletrencefalograma relativamente às epilepsias em geral. Investigação foi feita também em relação à cefaléia, aos achados neurológicos, liquóricos, radiológicos simples e contrastados e anátomo-patológicos. A análise dos resultados permitiu aos autores as seguintes conclusões: 1 No grupo de neurocisticercose o início da doença predominou na primeira e a partir da quarta década em relação às epilepsias em geral. 2 Dentre as manifestações clínicas predominaram as formas convulsivas da doença (61%, sendo as crises bravas-jacksonianas as menos freqüentes (4%; quando comparadas com as epilepsias em geral, verifica-se incidência menor das convulsões generalizadas na neurocisticercose. 3 Quanto ao tempo de doença, verifica-se predomínio das formas de duração mais curta (um ano ou menos na neurocisticercose. 4 A severidade da epilepsia, traduzida pela freqüência das crises, foi menor no grupo com neurocisticercose. 5 Excluídos os casos com anormalidades eletrencefalográficas contínuas, foram encontrados maiores índices percentuais de EEG normal na neurocisticercose que nas epilepsias em geral. 6 A cefaléia estava presente em 68% dos casos, assumindo caráter paroxístico na maior parte (78%; em 67% dos casos com cefaléia paroxística não havia concomitantemente sinais de hipertensão intracraniana; nos casos com cefaléia contínua, em apenas dois (13% esses sinais não estavam presentes. 7 Na maior parte dos casos (62% as manifestações epilépticas se apresentaram isoladamente, sem sinais neurol

  17. The CERES / NA45 experiment

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    Ceres is one of the second generation heavy ion experiments at CERN's SPS. It is dedicated to the study of electron-positron pairs in relativistic nuclear collisions. NA45 is one of the seven experiments (NA44, NA45, NA49, NA50, NA52, WA97/NA57 and WA98) involved in CERN's Heavy Ion programme which provided evidence for the existence of a new state of matter, the quark-gluon plasma. In this state, quarks, instead of being bound up into more complex particles such as protons and neutrons, are liberated and roam freely. Theory predicts that this state must have existed at about 10 microseconds after the Big Bang, before the formation of matter as we know it today.

  18. na Perua

    Directory of Open Access Journals (Sweden)

    Jorge Carvalho

    1989-01-01

    Full Text Available Antes de se caracterizar como tentativa de ensaio ou de análise a qualquer coisa, o presente artigo tem, antes de mais nada, a pretensão de se constituir uma provocação ao debate acerca da questão do esporte na escola. A provocação parte basicamente do relato da minha experiência pessoal como Secretário da Educação do Município de Aracaju, cargo que exerci no período de 1º de janeiro de 1986 a 27 de janeiro de 1987.

  19. Envolvimento pulmonar na polimiosite

    Directory of Open Access Journals (Sweden)

    Direndra Hasmucrai

    2010-07-01

    Full Text Available Resumo: Introdução: A polimiosite (PM e a dermatomiosite são classificadas como miopatias inflamatórias idiopáticas. O envolvimento pulmonar por PM é pouco frequente, estando descrito na literatura em cerca de 10% de casos.Os autores apresentam um caso de uma mulher de 75 anos, com queixas de febre, perda ponderal, artralgias, mialgias e diminuição simétrica e proximal da força muscular com impotência funcional dos membros superiores e inferiores, com início um mês antes do internamento. Apresentava infiltrados pulmonares na telerradiografia de tórax. Após estudo exaustivo estabeleceu-se o diagnóstico de envolvimento pulmonar na forma de pneumonia organizativa por PM. Efectuou-se corticoterapia e terapêutica com micofenolato com melhoria clínica, analítica e radiológica.Conclusão: Neste caso, foi a alteração na telerradiografia de tórax numa doente sem sintomatologia respiratória que levou ao estudo exaustivo até ao diagnóstico de PM, realçando mais uma vez a importância da telerradiografia no rastreio de patologias de outros foros.Rev Port Pneumol 2010; XVI (4: 671-677 Abstract: Introduction: Polymyositis and dermatomyositis are classified as idiopathic inflammatory myopathies. Interstitial lung disease is rare and is described in the literature in about 10% of cases.The authors describes a case of 75 year old woman presenting with one month evolution of fever, weight loss, arthralgia, myalgia and symmetric and proximal muscle weakness of upper and lower limbs. Nonspecific interstitial changes was found in chest X-ray. After exhaustive study, the diagnosis of pulmonary envolvement in the form of organizing pneumonia by polymyositis, was established. Glucocorticoids and mycophenolate were prescribed with good clinical, analytical and radiological outcome.Conclusion: In this case, it was the changes in the chest X-ray in a patient without respiratory sym ptomatology, that conducted to exhaustive study to polymyositis

  20. Envolvimento pulmonar na polimiosite

    Directory of Open Access Journals (Sweden)

    Direndra Hasmucrai

    2010-07-01

    Full Text Available Resumo: Introdução: A polimiosite (PM e a dermatomiosite são classificadas como miopatias inflamatórias idiopáticas. O envolvimento pulmonar por PM é pouco frequente, estando descrito na literatura em cerca de 10% de casos.Os autores apresentam um caso de uma mulher de 75 anos, com queixas de febre, perda ponderal, artralgias, mialgias e diminuição simétrica e proximal da força muscular com impotência funcional dos membros superiores e inferiores, com início um mês antes do internamento. Apresentava infiltrados pulmonares na telerradiografia de tórax. Após estudo exaustivo estabeleceu-se o diagnóstico de envolvimento pulmonar na forma de pneumonia organizativa por PM. Efectuou-se corticoterapia e terapêutica com micofenolato com melhoria clínica, analítica e radiológica. Conclusão: Neste caso, foi a alteração na telerradiografia de tórax numa doente sem sintomatologia respiratória que levou ao estudo exaustivo até ao diagnóstico de PM, realçando mais uma vez a importância da telerradiografia no rastreio de patologias de outros foros. Abstract: Introduction: Polymyositis and dermatomyositis are classified as idiopathic inflammatory myopathies. Interstitial lung disease is rare and is described in the literature in about 10% of cases.The authors describes a case of 75 year old woman presenting with one month evolution of fever, weight loss, arthralgia, myalgia and symmetric and proximal muscle weakness of upper and lower limbs. Nonspecific interstitial changes was found in chest X-ray. After exhaustive study, the diagnosis of pulmonary envolvement in the form of organizing pneumonia by polymyositis, was established. Glucocorticoids and mycophenolate were prescribed with good clinical, analytical and radiological outcome. Conclusion: In this case, it was the changes in the chest X-ray in a patient without respiratory symptomatology, that conducted to exhaustive study to polymyositis diagnosis, enhancing once again the

  1. Comprometimento pulmonar na leptospirose

    Directory of Open Access Journals (Sweden)

    Jorge Eduardo Manhães de Carvalho

    1992-03-01

    Full Text Available Em 23 pacientes com leptospirose apresentando comprometimento pulmonar, internados no Hospital Universitário Antônio Pedro da XJFF, Niterói, hemoptise e hemoptóicos foram observados em 21,7% e 30,4%, respectivajnente. Gasometria arterial revelou hipoxemia e hipocapnia na maioria dos casos. Radiografia de tórax em 15 pacientes mostrou comprometimento alveolar em 60%, comprometimento intersticial-reticular em 6%, padrão misto (alveolar e intersticial em20%e ausência de alterações radiológicas em 14%. A necrópsiade 13 pacientes mostrou edema, congestão e hemorragia nos pulmões em 100% dos casos. A hemorragia foi focal em 46% e difusa em 54% dos casos. Houve formação de membrana hialina em 30% e trombos de fibrina em 46% dos pulmões estudados, o que estabelece o diagnóstico da coagulação intravascular disseminada e a ocorrência da síndrome de angústia respiratória na leptospirose.

  2. ANALIZA POSLOVNE KULTURE NA JAPONSKEM

    OpenAIRE

    Ocvirk, Katja

    2012-01-01

    Poslovanje na mednarodnih trgih se z globalizacijo vedno bolj spreminja. V delu diplomskega seminarja sem opredelila kulturo in opisala njene pomembne sestavine ter značilnosti. Spoznala sem, da mora biti poslovnež, ki deluje na mednarodnem trgu, zelo dobro pripravljen in seznanjen s kulturnimi razlikami, da se izogne nepotrebnim napakam in spodrsljajem. Menim, da moramo pri poslovanju s poslovnimi partnerji, ki prihajajo iz drugih kultur, vedeti, kako deluje njihovo poslovno okolje. Na ...

  3. NA48 prototype calorimeter

    CERN Multimedia

    1990-01-01

    This is a calorimeter, a detector which measures the energy of particles. When in use, it is filled with liquid krypton at -152°C. Electrons and photons passing through interact with the krypton, creating a shower of charged particles which are collected on the copper ribbons. The ribbons are aligned to an accuracy of a tenth of a millimetre. The folding at each end allows them to be kept absolutely flat. Each shower of particles also creates a signal in scintillating material embedded in the support disks. These flashes of light are transmitted to electronics by the optical fibres along the side of the detector. They give the time at which the interaction occurred. The photo shows the calorimeter at NA48, a CERN experiment which is trying to understand the lack of anti-matter in the Universe today.

  4. Na Cauda do Cometa

    Science.gov (United States)

    Voelzke, M. R.

    2009-01-01

    Quando viam um cometa, os antigos gregos imaginavam uma estrela com uma vasta cabeleira. Não à toa, a palavra deriva do termo koma, que significa cabelo. Constituídos por fragmentos de gelo e gases, os cometas possuem um núcleo sólido, que pode ter vários quilômetros de diâmetro, e uma cauda que sempre aponta na direção contrária ao Sol, devido aos ventos solares. Graças à aparência de pontos luminosos em movimento (ao contrário de outros astros, que parecem estáticos), esses corpos celestes foram interpretados por diferentes povos com muito misticismo, inspirando mitos tanto de boas-novas como de maus presságios. Conheça algumas dessas histórias:

  5. A ENGENHARIA NA ESCOLA

    Directory of Open Access Journals (Sweden)

    Valéria Pelizzer Casara

    2015-04-01

    Full Text Available Este projeto teve por objetivo principal mostrar às jovens do ensino médio, como as áreas de exatas e de engenharia podem estar inseridas em situações rotineiras por elas vivenciadas e incentivá-las para ingressarem nessas áreas. O projeto foi executado na escola de ensino Médio Nelson Horostecki na cidade de Chapecó, Santa Catarina. Mostrou-se de forma simples que as áreas de exatas e de engenharia têm aplicações práticas nas nossas vidas. No desenvolvimento do projeto, realizaram-se oficinas na escola cujo tema principal abordado foi o processo de fabricação do chocolate, visto que o mesmo é um produto muito apreciado pelas adolescentes. Dentro dessa temática, foram trabalhadas as questões que envolvem conhecimentos das áreas de exatas e de engenharia, mais especificamente a Engenharia Ambiental. O projeto auxiliou na formação cidadã e também na escolha profissional das meninas. Muitas das alunas participantes nunca haviam tido contato direto com alunos graduandos de cursos na área das exatas. Mais ainda, este projeto oportunizou a aproximação da universidade com a comunidade externa. Palavras-chave: Extensão Universitária, Ciências Exatas e Engenharia, Chocolate, Oficinas.   Engineering in the school Abstract: The main objective of this project was to show high school female students how the exact sciences and engineering can be included in their routine situations encouraging them to entering in these areas. The project was carried out at the Nelson Horostecki High School in Chapecó, Santa Catarina State, Brazil. It was showed in a simple manner how exact sciences and engineering have practical applications in our lives. Workshops were conducted in the school during the execution of the project in which the main subject was the chocolate manufacturing process, since chocolate is a product greatly appreciated by the young female people. Within this matter, the activities were performed using the knowledge of

  6. Holothurian (Echinodermata) Diversity in the Glorieuses Archipelago

    African Journals Online (AJOL)

    Abstract—Due to their isolation, Eparses Islands provide a valuable opportunity to investigate biodiversity in the absence of anthropogenic influence. The Glorieuses. Archipelago forms part of the Eparses Islands, or the French scattered islands in the Mozambique Channel (Western Indian Ocean). Inventories of several ...

  7. Molecular phylogeny of extant Holothuroidea (Echinodermata).

    Science.gov (United States)

    Miller, Allison K; Kerr, Alexander M; Paulay, Gustav; Reich, Mike; Wilson, Nerida G; Carvajal, Jose I; Rouse, Greg W

    2017-06-01

    Sea cucumbers (Holothuroidea) are a morphologically diverse, ecologically important, and economically valued clade of echinoderms; however, the understanding of the overall systematics of the group remains controversial. Here, we present a phylogeny of extant Holothuroidea assessed with maximum parsimony, maximum likelihood, and Bayesian approaches using approximately 4.3kb of mt- (COI, 16S, 12S) and nDNA (H3, 18S, 28S) sequences from 82 holothuroid terminals representing 23 of the 27 widely-accepted family-ranked taxa. Currently five holothuroid taxa of ordinal rank are accepted. We find that three of the five orders are non-monophyletic, and we revise the taxonomy of the groups accordingly. Apodida is sister to the rest of Holothuroidea, here considered Actinopoda. Within Actinopoda, Elasipodida in part is sister to the remaining Actinopoda. This latter clade, comprising holothuroids with respiratory trees, is now called Pneumonophora. The traditional Aspidochirotida is paraphyletic, with representatives from three orders (Molpadida, Dendrochirotida, and Elasipodida in part) nested within. Therefore, we discontinue the use of Aspidochirotida and instead erect Holothuriida as the sister group to the remaining Pneumonophora, here termed Neoholothuriida. We found four well-supported major clades in Neoholothuriida: Dendrochirotida, Molpadida and two new clades, Synallactida and Persiculida. The mapping of traditionally-used morphological characters in holothuroid systematics onto the phylogeny revealed marked homoplasy in most characters demonstrating that further taxonomic revision of Holothuroidea is required. Two time-tree analyses, one based on calibrations for uncontroversial crown group dates for Eleutherozoa, Echinozoa and Holothuroidea and another using these calibrations plus four more from within Holothuroidea, showed major discrepancies, suggesting that fossils of Holothuroidea may need reassessment in terms of placing these forms with existing crown clades. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Asteroidea (Echinodermata) from the Guyana Shelf

    NARCIS (Netherlands)

    Walenkamp, J.H.C.

    1979-01-01

    CONTENTS Introduction.......... 3 Acknowledgements........ 4 List of the stations where Asteroidea were collected........ 4 Taxonomic report......... 7 Identification.......... 9 Survey of the species........ 11 Literature cited......... 88 Index............ 95 INTRODUCTION In a previous paper

  9. Evolutionary history of regeneration in crinoids (Echinodermata).

    Science.gov (United States)

    Gahn, Forest J; Baumiller, Tomasz K

    2010-10-01

    The fossil record indicates that crinoids have exhibited remarkable regenerative abilities since their origin in the Ordovician, abilities that they likely inherited from stem-group echinoderms. Regeneration in extant and fossil crinoids is recognized by abrupt differences in the size of abutting plates, aberrant branching patterns, and discontinuities in carbon isotopes. While recovery is common, not all lost body parts can be regenerated; filling plates and overgrowths are evidence of non-regenerative healing. Considering them as a whole, Paleozoic crinoids exhibit the same range of regenerative and non-regenerative healing as Recent crinoids. For example, Paleozoic and extant crinoids show evidence of crown regeneration and stalk regrowth, which can occur only if the entoneural nerve center (chambered organ) remains intact. One group of Paleozoic crinoids, the camerates, may be an exception in that they probably could not regenerate their complex calyx-plating arrangements, including arm facets, but their calyxes could be healed with reparative plates. With that exception, and despite evidence for increases in predation pressure, there is no compelling evidence that crinoids have changed though time in their ability to recover from wounds. Finally, although crinoid appendages may be lost as a consequence of severe abiotic stress and through ontogenetic development, spatiotemporal changes in the intensity and frequency of biotic interactions, especially direct attacks, are the most likely explanation for observed patterns of regeneration and autotomy in crinoids. © The Author 2010. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.

  10. [The echinoderms (Echinodermata) from El Salvador].

    Science.gov (United States)

    Enrique Barraza, José; Roberto Hasbún, Carlos

    2005-12-01

    A list of echinoderms from El Salvador (tropical eastern Pacific) is presented. The results were obtained from field surveys (between the years 2000 and 2004), the scarce literature sources, and Internet information. A total of 37 species and six genera are reported. The most abundant echinoderms in rocky shores were: Phataria unifascialis, Echinometra vanbrunti, Holothuria kefersteini, as well as Astropecten armatus in soft bottoms.

  11. Hodler à Iéna

    OpenAIRE

    2017-01-01

    A la mort de Hodler, on demanda que les planches qui recouvrait la fresque de Iéna, depuis la protestation contre le bombardement de Reims, soit enlevées. Les autorités de Iéna ont refusé énergiquement.

  12. Valores na escola

    Directory of Open Access Journals (Sweden)

    Menin Maria Suzana De Stefano

    2002-01-01

    Full Text Available Neste texto pretende-se discorrer sobre valores morais na escola e suas implicações para a formação de professores. Para tanto discutir-se-á, em primeiro lugar, e brevemente, o que são valores morais, ou éticos, e como a escola pode situar-se em relação a eles. Em seguida, serão relatadas algumas observações a respeito de valores de professores e práticas daí decorrentes. São comentados resultados de pesquisa que ilustram a transmissão de valores de forma doutrinal e a educação moral e cívica tal como realizada na ditadura militar, e, por outro lado, a posição relativista e/ou de laissez-faire que certas escolas podem adotar, metodologicamente, sobre a educação em valores. Finalmente, defender-se-á a idéia de que é necessária uma discussão sobre valores pelos diversos membros da escola e uma opção por uma metodologia para ensiná-los, seja os professores, em sua formação inicial e continuada, seja os alunos. A teoria de desenvolvimento moral de Jean Piaget será apresentada como uma referência possível para a educação em valores. Exemplos de situações escolares de conflito de valores entre direção, pais e alunos são discutidas para ilustrar como uma escola pode adotar um procedimento democrático de educação em valores, que se apresenta como um terceiro caminho possível de educação moral nas escolas, além das posições doutrinárias ou relativistas.

  13. A aposta na filosofia

    Directory of Open Access Journals (Sweden)

    Márcio Suzuki

    2011-12-01

    Full Text Available Para Hume, filosofar é uma atividade semelhante às demais ocupações humanas. A decisão que leva à atividade filosófica é menos resultado de uma argumentação teórica do que fruto de um cálculo prático, que é entendido como uma caça ou um jogo. O objetivo deste trabalho será o de mostrar que no jogo filosófico perde quem joga sério demais. A aposta na filosofia tem que passar pelo bom humor e pela diversão: uma resposta a Pascal?For Hume, philosophy is in itself neither more nor less important than other human activities. On the contrary, it can be explained from its resemblance with game and hunting. If one chooses to dedicate himself to philosophy, his decision is not the consequence of logical reasoning, but depends on practical evaluation, which has something to do with gambling. The following text tries to show that in philosophy, like in other games, the loser will be the one who plays too earnestly. The philosophical game requires good humour and some relaxation: Is this a good answer to Pascal's pari?

  14. A Arquitetura na Cidade

    Directory of Open Access Journals (Sweden)

    Euler Sandeville Junior

    2013-07-01

    Full Text Available Este artigo é uma reflexão sobre três casos em que a arquitetura define a configuração do espaço público, investigando seus significados e pressupostos. São levantadas questões que não comportam respostas definitivas, mas que induzem a alguns parâmetros para discutir a atuação do arquiteto no espaço público, nas áreas centrais de nossas cidades. Nosso título é, sem dúvida, devedor do célebre trabalho de Aldo Rossi, a Arquitetura da cidade (1966. Porém, nos ocupamos apenas da inserção da arquitetura na cidade e numa perspectiva teórica muito distinta, reconhecendo para o projeto do objeto arquitetônico uma dependência do espaço e do tempo e das relações sociais que assim se estabelecem. São analisados o Memorial da América Latina, a estação Barra Funda do Metrô e a Praça da Sé. São aqui entendidos como campos de projeto da paisagem e, como tal, problematizados.

  15. O SUBLIME NA MODERNIDADE

    Directory of Open Access Journals (Sweden)

    Martha de Almeida

    2009-03-01

    Full Text Available A obra Uma investigação filosófica sobre a origem de nossas idéias do sublime e dobelo, do sensualista inglês Edmund Burke (1757, data as origens do sublime na Modernidade. Nosublime ocorre é um prazer ligado à dor, um "horror delicioso" que sentimos quando acreditamosque estamos em perigo sem que isso esteja ocorrendo realmente. Em O mundo como Vontade erepresentação Schopenhauer assume as influências que sofreu de Kant no que diz respeito à suainterpretação sobre o belo e o sublime, porém difere dele quanto à natureza dessa impressão. ParaSchopenhauer a experiência estética pressupõe a dissolução da subjetividade num movimento decontemplação das idéias livre do querer imposto pela vontade individual. As idéias deSchopenhauer influenciaram a estética do Nietzsche de O nascimento da tragédia.

  16. SPOLNO NADLEGOVANJE NA DELOVNEM MESTU

    OpenAIRE

    Rubič, Gašper

    2016-01-01

    V diplomskem delu smo v uvodu predstavili problem spolnega nadlegovanja na delovnem mestu in predstavili podjetje TEKSTIL d.d. V nadaljevanju smo z anketo raziskali, ali problem spolnega nadlegovanja na delovnem mestu v obravnavanem podjetju obstaja in če, kako se nanj odziva okolje. V teoretičnem delu smo nadaljevali in predstavili definicijo spolnega nadlegovanja, ki je kakršna koli oblika nezaželenega verbalnega in neverbalnega ali fizičnega ravnanja spolne narave z učinkom ali nameno...

  17. Hemisferectomia na hemiplegia infantil

    Directory of Open Access Journals (Sweden)

    Rolando A. Tenuto

    1956-03-01

    Full Text Available Os autores relatam o caso de um paciente com 18 anos de idade, portador de paralisia cerebral instalada aos 4 anos de idade após moléstia febril prolongada (hemiplegia esquerda, crises convulsivas generalizadas, freqüentes e rebeldes à medicação, deficiência mental e alterações de conduta. O eletrencefalograma e o pneumencefalograma revelaram alterações graves do hemisfério direito; tendo o primeiro destes exames demonstrado a existência de perturbações propagadas ao outro hemisfério. Foi praticada a hemisferectomia direita. Durante o ato cirúrgico, por exigência técnica foram extirpados, além do hemisfério cerebral, os dois terços rostrais do núcleo caudado e o núcleo amigdalóide. No pós-operatório foi intercorrência de osteomielite e meningite, medicadas com antibióticos e seqüestrectomia. Apesar da complicação pós-operatória, instalou-se progressiva melhora em relação à conduta social; diminuiu também a espasticidade no membro inferior esquerdo e não mais se repetiram as crises convulsivas. Não foram observadas modificações quanto ao rendimento intelectual e quanto aos distúrbios sensitivos que existiam antes da intervenção cirúrgica. O exame neurocular mostrou hemianopsia homônima esquerda. Êstes resultados são concordantes com os assinalados na literatura sobre o assunto.

  18. Active transport of Na+ by reconstituted Na,K-ATPase

    International Nuclear Information System (INIS)

    Boldyrev, A.A.; Svinukhova, I.A.

    1987-01-01

    The ability of ATP, CTP, ITP, GTP, and UTP to support ouabain-sensitive accumulation of Na + by proteoliposomes with a reconstituted Na/K-pump was investigated. At a low [Na + ]/[K + ] ratio in the medium (20 mM/50 mM), a correlation is observed between the proton-accepting capacity of the nucleotide and its effectiveness as a substrate of active transport. To test the hypothesis of the importance of the presence of a negative charge in the 1-position of the purine (3-pyrimidine) base of the nucleotide for mutual transitions between the Na- and K-conformations of Na,K-ATPase they used two analogs of ATP: N 1 -hydroxy-ATP, possessing proton acceptor capacity, and N 1 -methoxy-ATP, in the molecule of which the negative charge is quenched by a methyl group. The first substrate supports active accumulation of Na + in proteoliposomes at the same rate as ATP, whereas the second substrate is relatively ineffective

  19. Risbjerg: Historisk stemmeskred med NA

    DEFF Research Database (Denmark)

    Thomsen, Søren Risbjerg

    2007-01-01

    ANALYSE: NA flytter 12,3 pct. af stemmerne i majs meningsmålinger - historisk mange vælgere på en måned, skriver professor Risbjerg. Udgivelsesdato: 3. juni 2007......ANALYSE: NA flytter 12,3 pct. af stemmerne i majs meningsmålinger - historisk mange vælgere på en måned, skriver professor Risbjerg. Udgivelsesdato: 3. juni 2007...

  20. Na via do Behemoth

    Directory of Open Access Journals (Sweden)

    Gérard Rabinovitch

    2008-06-01

    Full Text Available O momento nazista permanece um enigma impensado de que a cultura contemporânea continua cativa. O autor levanta a hipótese de que a persistência desse enigma e seus estragos duráveis se devem à insistência dos pensamentos político, sociológico e filosófico em construírem o nazismo à luz da metáfora hobbesiana do Leviatã. Propõe retomar a questão do nazismo sob a perspectiva do Behemoth, antônimo do Leviatã. Para tanto, sugere a necessidade de retornar a Freud e à psicanálise, balizas de um possível novo pensamento do político que escrutine a destrutividade nazista. Propõe ainda sondar as homologias entre nazismo, corjas e máfias, com base na figura da " heroicização da violência" que lhes seria comum. E avança um modelo " econômico" : a quimera, suscetível de capturar o caráter heterotópico e heterocrônico de sua construção criminosa.The paths of Behemoth. The Nazi moment remains as the thoughtless enigma of which contemporary culture is still captive. The author raises the hypothesis where the persistency of this enigma and its durable damages are due to the insistence of the political, social and philosophical thoughts in building the Nazism at the view of the Hobbesian metaphor of Leviathan. It is here proposed to resume the Nazism matter under Behemoth's perspective, antonym to Leviathan. For such, it is suggested a necessity to look back at Freud and the psychoanalysis, structured by a possible new political thought which scrutinizes the destructivity of the Nazism. It is also here proposed to gaze at the homologies between Nazism, mafias and gangs, with a base in the figure of " violence as a heroically act" that are their common ground. The author also advances an economical model: the chimera susceptible to capture the heterotopic and heterochronic character of its criminal construction.

  1. Estresse ocupacional na enfermagem atuante na unidade de terapia intensiva

    OpenAIRE

    Borges Teixeira, Larissa; Portela Veloso, Lorena Uchôa; Universidade Estadual do Piauí; Pereira Ribeiro, Ítalo Arão; Universidade Estadual do Piauí; Nunes de Oliveira, Tauane; Instituto de Ensino Superior Franciscano; Leal Cortez, Antônio Carlos; Universidade Estadual do Piauí

    2017-01-01

    Introdução: O estresse tem sido um dos problemas que mais tem acometido a equipe de enfermagem dentro da unidade de terapia intensiva (UTI), causando prejuízo funcional, bem como instabilidade na saúde desses profissionais. Objetivo: Descrever, através da revisão integrativa, o estresse no trabalho da enfermagem na UTI, bem como identificar fatores, sinais e sintomas associados ao estresse ocupacional. Método: Trata-se de uma pesquisa integrativa, utilizando como banco de dados a Biblioteca V...

  2. Corpo e sexualidade na gravidez

    Directory of Open Access Journals (Sweden)

    Natalúcia Matos Araújo

    2012-06-01

    Full Text Available Estudo etnográfico que teve como objetivo compreender como as gestantes vivenciam os processos fisiológicos do seu corpo durante a gestação e a sua repercussão na sexualidade. A pesquisa envolveu sete mulheres residentes em bairro popular de São Paulo. Na coleta de dados, utilizou-se observação participante e entrevista com questões norteadoras. Os dados foram apresentados na forma de narrativa e posteriormente organizados nas categorias: Percebendo as transformações corporais; Convivendo com as mudanças no corpo; Sentimentos e sensações na vida sexual durante a gestação e imaginando o corpo e a sexualidade após a gestação. As mulheres referiram-se às transformações do corpo como desconfortos e expressaram a preocupação de que fossem definitivas. Expressaram o desejo de que, após o parto, o corpo volte a ser como era e que volte a sentir desejo sexual. O reconhecimento destes fatos constitui-se numa ferramenta primordial na adequação das práticas profissionais.

  3. All new for NA62

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    This week sees the start of the first run of the new NA62 experiment. This will be a unique opportunity for the collaboration to test its new beam, new detectors and new data acquisition system before the physics run in 2014. Speaking to the Bulletin, the NA62 technical coordinator Ferdinand Hahn shares the many challenges that the various teams faced to be on time for beam. Ready, steady, start!   A Large Angle Veto detector (white) in place in the NA62 decay volume (blue). With components from almost all the detectors in place downstream of the decay point of the mother particles – the kaons – and of the KTAG detector that tags the kaons before they decay, NA62 is ready for its first technical run. This unique run will test all the equipment as well as the trigger and the data acquisition systems. “This year, we will have about five weeks of beam from the SPS before the long shutdown of all the CERN machines,” says Ferdinand Hahn, NA62 Technical Co-...

  4. Kostel na Lesné

    OpenAIRE

    Pospíšil, Vojtěch

    2017-01-01

    Tato teoretická diplomová práce se zabývá prostorovou akustikou a s tím úzce spojenou problematikou doby dozvuku. Součástí práce je zpracování návrhu akustických úprav kostela na základě ručního výpočtu, který byl dále upravován ve specializovaném softwaru Odeon Room Acoustics Program. Pro okolní zástavbu kostela byla vytvořena hluková studie v programu Hluk+, aby bylo posouzeno, jaký bude mít tato novostavba hlukový dopad z kostelních zvonů dopad na své okolí. Na základě specializace, bylo v...

  5. gigapanorama of NA 62 cavern

    CERN Multimedia

    Brice, Maximilien

    2015-01-01

    The image shows the new rare Kaon decay experiment at CERN, called NA62. The NA62 experiment is 270 metres long and includes a 120-metre-long vacuum tank, shown here, housing several of the particle detectors. (Note: the experiment axis is a straight line, the curving of the tank is an optical effect of the photo.) Kaons are particles that decay into lighter elementary particles. The kaon decay processes are mostly well known, except for some very rare decay modes. For example, NA62 is investigating a rare decay predicted by the Standard Model in which a kaon decays into one pion and two neutrinos. This process occurs only once every 10 billion decays. The understanding of such ultra-rare decays are of great importance because they test the Standard Model in energy ranges not accessible by direct measurements. They are therefore complementary to the measurements at the LHC. ultra high definition on demand (photolab@cern.ch).

  6. OGLAŠEVANJE NA FACEBOOKU

    OpenAIRE

    Renko, Katica

    2013-01-01

    V magistrskem delu smo se seznanili z oglaševanjem na Facebooku. S pregledom gradiva, ki nam je ponujeno, smo preverili pogoje, načine, oblike … oglaševanja, ki pa smo jih s pregledom situacije v praksi preverili in dopolnili. Ob zaključku dela lahko rečemo, da je oglaševanje preko FB enostavnejše, cenejše, dostopnejše, omogoča nam ažurnost in samo komunikacijo z naslovniki, ki so potencialni kupci naših ponudb. Množični mediji nam omogočajo mnogotero obliko oglaševanja. Izbrana oblika ponuja...

  7. MicroRaman, PXRD, EDS and microscopic investigation of magnesium calcite biomineral phases. The case of sea urchin biominerals

    Science.gov (United States)

    Borzęcka-Prokop, B.; Wesełucha-Birczyńska, A.; Koszowska, E.

    2007-02-01

    This study concerns Mg-calcite characterization (and in particular molecular structure and microstructural studies of mineral phases) of a sea urchin mineralised test and spines. Sea urchins are spiny sea animals (kingdom Animalia, phylum Echinodermata, class Echinoidea). Microscopic observations, SEM, EDS, PXRD and spectroscopic microRaman methods have been applied to characterize the biomineral parts of the sea urchin. The latter technique is very useful in research of biological systems and especially suitable for monitoring differences within biomineral phases exhibiting varieties of morphological forms. Crystalline magnesium calcium carbonate, Mg xCa 1- xCO 3 (magnesian calcite; space group R-3 cH; a = 4.9594(8) Å, c = 16.886(6) Å), has been identified as the predominant biomineral component.

  8. Opportunities and challenges for digital morphology

    Directory of Open Access Journals (Sweden)

    Prohaska Steffen

    2010-07-01

    Full Text Available Abstract Advances in digital data acquisition, analysis, and storage have revolutionized the work in many biological disciplines such as genomics, molecular phylogenetics, and structural biology, but have not yet found satisfactory acceptance in morphology. Improvements in non-invasive imaging and three-dimensional visualization techniques, however, permit high-throughput analyses also of whole biological specimens, including museum material. These developments pave the way towards a digital era in morphology. Using sea urchins (Echinodermata: Echinoidea, we provide examples illustrating the power of these techniques. However, remote visualization, the creation of a specialized database, and the implementation of standardized, world-wide accepted data deposition practices prior to publication are essential to cope with the foreseeable exponential increase in digital morphological data. Reviewers This article was reviewed by Marc D. Sutton (nominated by Stephan Beck, Gonzalo Giribet (nominated by Lutz Walter, and Lennart Olsson (nominated by Purificación López-García.

  9. Antarctic, Sub-Antarctic and cold temperate echinoid database

    Directory of Open Access Journals (Sweden)

    Benjamin Pierrat

    2012-06-01

    Full Text Available This database includes spatial data of Antarctic, Sub-Antarctic and cold temperate echinoid distribution (Echinodermata: Echinoidea collected during many oceanographic campaigns led in the Southern Hemisphere from 1872 to 2010. The dataset lists occurrence data of echinoid distribution south of 35°S latitude, together with information on taxonomy (from species to genus level, sampling sources (cruise ID, sampling dates, ship names and sampling sites (geographic coordinates and depth. Echinoid occurrence data were compiled from the Antarctic Echinoid Database (David et al., 2005a, which integrates records from oceanographic cruises led in the Southern Ocean until 2003. This database has been upgraded to take into account data from oceanographic cruises led after 2003. The dataset now reaches a total of 6160 occurrence data that have been checked for systematics reliability and consistency. It constitutes today the most complete database on Antarctic and Sub-Antarctic echinoids.

  10. NA60 frees the quarks

    CERN Multimedia

    2003-01-01

    Fitted with new state-of-the-art silicon detectors, NA60 is prepared to study the phase transition from confined hadronic matter to a deconfined (free) quark-gluon plasma, a state of matter which probably existed an instant after the Big Bang.

  11. Hodler et Iéna

    OpenAIRE

    2017-01-01

    Suites de la protestation contre le bombardement de la cathédrale de Reims. Le recteur de l'Université de Jena propose d'enlever le tableau monumental de Hodler "Départ des étudiants d'Iéna pour la guerre de libération contre Napoléon en 1813".

  12. NA62: Hidden Sector Physics

    CERN Document Server

    Cesarotti, Carissa Joyce

    2016-01-01

    Modern experimental physics is often probing for new physics by either finding deviations from predictions on extremely precise measurements, or by looking for a new signal that cannot be explained with existing models. The NA62 experiment at CERN does the former by measuring the ultra-rare decay $K^+ \\rightarrow \\pi^+ \

  13. The system NaVO3-Na2WO4-Na2W2O7

    International Nuclear Information System (INIS)

    Kazanbekov, V.R.; Gasanaliev, A.M.; Kazanbekov, R.G.

    1994-01-01

    Phase diagrams of sodium metavanadate-sodium ditungstate, sodium metavanadate-sodium tungstate systems and surface of primary crystallization of sodium metavabadate-sodium tungstate-sodium ditungstate system were studied. The system sodium metavanadate-sodium ditungstate is eutectic one. Compound NaVO 3 x2Na 2 WO 4 is formed in solid state in sodium metavanadate-sodium tungstate system. Liquidus surface of sodium metavanadate-sodium tungstate-sodium ditungstate is presented by three crystallization fields of initial components. Composition and melting point of ternary eutectics are determined

  14. Europlanet NA2 Science Networking

    Science.gov (United States)

    Harri, Ari-Matti; Szego, Karoly; Genzer, Maria; Schmidt, Walter; Krupp, Norbert; Lammer, Helmut; Kallio, Esa; Haukka, Harri

    2013-04-01

    Europlanet RI / NA2 Science Networking [1] focused on determining the major goals of current and future European planetary science, relating them to the Research Infrastructure that the Europlanet RI project [2] developed, and placing them in a more global context. NA2 also enhanced the ability of European planetary scientists to participate on the global scene with their own agenda-setting projects and ideas. The Networking Activity NA2 included five working groups, aimed at identifying key science issues and producing reference books on major science themes that will bridge the gap between the results of present and past missions and the scientific preparation of the future ones. Within the Europlanet RI project (2009-2012) the NA2 and NA2-WGs organized thematic workshops, an expert exchange program and training groups to improve the scientific impact of this Infrastructure. The principal tasks addressed by NA2 were: • Science activities in support to the optimal use of data from past and present space missions, involving the broad planetary science community beyond the "space club" • Science activities in support to the preparation of future planetary missions: Earth-based preparatory observations, laboratory studies, R&D on advanced instrumentation and exploration technologies for the future, theory and modeling etc. • Develop scientific activities, joint publications, dedicated meetings, tools and services, education activities, engaging the public and industries • Update science themes and addressing the two main scientific objectives • Prepare and support workshops of the International Space Science Institute (ISSI) in Bern and • Support Trans National Activities (TNAs), Joined Research Activities (JRAs) and the Integrated and Distributed Information Service (IDIS) of the Europlanet project These tasks were achieved by WG workshops organized by the NA2 working groups, by ISSI workshops and by an Expert Exchange Program. There were 17 official WG

  15. Na+-stimulated ATPase of alkaliphilic halotolerant cyanobacterium Aphanothece halophytica translocates Na+ into proteoliposomes via Na+ uniport mechanism

    Directory of Open Access Journals (Sweden)

    Soontharapirakkul Kanteera

    2010-08-01

    Full Text Available Abstract Background When cells are exposed to high salinity conditions, they develop a mechanism to extrude excess Na+ from cells to maintain the cytoplasmic Na+ concentration. Until now, the ATPase involved in Na+ transport in cyanobacteria has not been characterized. Here, the characterization of ATPase and its role in Na+ transport of alkaliphilic halotolerant Aphanothece halophytica were investigated to understand the survival mechanism of A. halophytica under high salinity conditions. Results The purified enzyme catalyzed the hydrolysis of ATP in the presence of Na+ but not K+, Li+ and Ca2+. The apparent Km values for Na+ and ATP were 2.0 and 1.2 mM, respectively. The enzyme is likely the F1F0-ATPase based on the usual subunit pattern and the protection against N,N'-dicyclohexylcarbodiimide inhibition of ATPase activity by Na+ in a pH-dependent manner. Proteoliposomes reconstituted with the purified enzyme could take up Na+ upon the addition of ATP. The apparent Km values for this uptake were 3.3 and 0.5 mM for Na+ and ATP, respectively. The mechanism of Na+ transport mediated by Na+-stimulated ATPase in A. halophytica was revealed. Using acridine orange as a probe, alkalization of the lumen of proteoliposomes reconstituted with Na+-stimulated ATPase was observed upon the addition of ATP with Na+ but not with K+, Li+ and Ca2+. The Na+- and ATP-dependent alkalization of the proteoliposome lumen was stimulated by carbonyl cyanide m - chlorophenylhydrazone (CCCP but was inhibited by a permeant anion nitrate. The proteoliposomes showed both ATPase activity and ATP-dependent Na+ uptake activity. The uptake of Na+ was enhanced by CCCP and nitrate. On the other hand, both CCCP and nitrate were shown to dissipate the preformed electric potential generated by Na+-stimulated ATPase of the proteoliposomes. Conclusion The data demonstrate that Na+-stimulated ATPase from A. halophytica, a likely member of F-type ATPase, functions as an electrogenic Na

  16. Photodesorption of Na atoms from rough Na surfaces

    DEFF Research Database (Denmark)

    Balzer, Frank; Gerlach, R.; Manson, J.R.

    1997-01-01

    We investigate the desorption of Na atoms from large Na clusters deposited on dielectric surfaces. High-resolution translational energy distributions of the desorbing atoms are determined by three independent methods, two-photon laser-induced fluorescence, as well as single-photon and resonance......-enhanced two-photon ionization techniques. Upon variation of surface temperature and for different substrates (mica vs lithium fluoride) clear non-Maxwellian time-of-flight distributions are observed with a cos θ angular dependence and most probable kinetic energies below that expected of atoms desorbing from...... atoms are scattered by surface vibrations. Recent experiments providing time constants for the decay of the optical excitations in the clusters support this model. The excellent agreement between experiment and theory indicates the importance of both absorption of the laser photons via direct excitation...

  17. Photodesorption of Na atoms from rough Na surfaces

    DEFF Research Database (Denmark)

    Balzer, Frank; Gerlach, R.; Manson, J.R.

    1997-01-01

    atoms are scattered by surface vibrations. Recent experiments providing time constants for the decay of the optical excitations in the clusters support this model. The excellent agreement between experiment and theory indicates the importance of both absorption of the laser photons via direct excitation......We investigate the desorption of Na atoms from large Na clusters deposited on dielectric surfaces. High-resolution translational energy distributions of the desorbing atoms are determined by three independent methods, two-photon laser-induced fluorescence, as well as single-photon and resonance......-enhanced two-photon ionization techniques. Upon variation of surface temperature and for different substrates (mica vs lithium fluoride) clear non-Maxwellian time-of-flight distributions are observed with a cos θ angular dependence and most probable kinetic energies below that expected of atoms desorbing from...

  18. Low coverage sequencing of three echinoderm genomes: the brittle star Ophionereis fasciata, the sea star Patiriella regularis, and the sea cucumber Australostichopus mollis.

    Science.gov (United States)

    Long, Kyle A; Nossa, Carlos W; Sewell, Mary A; Putnam, Nicholas H; Ryan, Joseph F

    2016-01-01

    There are five major extant groups of Echinodermata: Crinoidea (feather stars and sea lillies), Ophiuroidea (brittle stars and basket stars), Asteroidea (sea stars), Echinoidea (sea urchins, sea biscuits, and sand dollars), and Holothuroidea (sea cucumbers). These animals are known for their pentaradial symmetry as adults, unique water vascular system, mutable collagenous tissues, and endoskeletons of high magnesium calcite. To our knowledge, the only echinoderm species with a genome sequence available to date is Strongylocentrotus pupuratus (Echinoidea). The availability of additional echinoderm genome sequences is crucial for understanding the biology of these animals. Here we present assembled draft genomes of the brittle star Ophionereis fasciata, the sea star Patiriella regularis, and the sea cucumber Australostichopus mollis from Illumina sequence data with coverages of 12.5x, 22.5x, and 21.4x, respectively. These data provide a resource for mining gene superfamilies, identifying non-coding RNAs, confirming gene losses, and designing experimental constructs. They will be important comparative resources for future genomic studies in echinoderms.

  19. Obiteljska i bračna psihoterapija

    OpenAIRE

    Štalekar, Vlasta

    2010-01-01

    U radu je ukratko prikazana povijest obiteljske terapije na temelju koje se prati razvoj novih koncepata i terapijskih modela. Prikazana je podjela obiteljskih i bračnih terapija na brojne pravce, a navedene u ovom radu su sistemska, dinamska, strukturalna, strateška, transgeneracijska, iskustvena (prvenstveno je didaktičkog karaktera jer se u praksi ovi modeli uvelike preklapaju i nadopunjuju). Svaki terapijski model na jedinstven način tumači disfunkcije obiteljskog sustava t...

  20. Novel aspects of Na+,K+-ATPase

    OpenAIRE

    Aizman, Oleg

    2002-01-01

    Na,K-ATPase, an integral membrane protein expressed in each eukaryotic cell, serves as the major determinant of intracellular ion composition. In the current study we investigated novel aspects of Na,K-ATPase function and regulation. It is well established that Na,K-ATPase activity is regulated by reversible phosphorylation. New findings in this study are: 1) the level of intracellular Ca 2. concentration determines the functional effects of PKA and PKC-mediated Na,K-ATP...

  1. Carne suína

    OpenAIRE

    Ortigara, Claudino

    2000-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. A carne suína é a fonte de proteína animal mais consumida no mundo. No entanto, em muitos países e em especial no Brasil o consumo per capita é muito baixo. Como conseqüência disso, limita-se o crescimento do segmento produtivo e uma série de benefícios socioeconômicos que são gerados pela atividade suinocultura.Com esse trabalho, buscamos uma explicação para entender a resistência da população ao consum...

  2. Economia na consulta de Endodontia

    OpenAIRE

    Pinto, Diogo Filipe Cardoso

    2016-01-01

    Introdução: Em Portugal a realidade actual, clínica e financeira do exercício da Medicina Dentária é bem distinta da do final do séc. XX devido à pletora de Médicos Dentistas e à baixa de honorários por acto Médico registada nos últimos anos. Objectivos: Este trabalho teve como objectivo perceber um pouco sobre os detalhes a ter em consideração aquando da abertura de uma clínica centrada na realização de tratamentos na área da Endodontia, e como publicitá-la de forma legal e apelativa. Pre...

  3. A Umbanda Portuguesa na Internet

    Directory of Open Access Journals (Sweden)

    Ismael Pordeus Júnior

    2004-01-01

    Full Text Available A partir de considerações sobre o processo de transculturação da Umbanda de Omolocô vou a propósito do grupo religioso do Terreiro de Umbanda Ogum Megê em Lisboa - Portugal discutir a textualização da memória. Como outras religiões que visam hoje o universal a Umbanda utiliza novas tecnologias disponíveis na Internet. Esse novo meio de comunicação favorece o processo de transculturação religiosa. Utilizando uma abordagem antropológica procuro realizar um estudo dos sites da Umbanda portuguesa na Internet, propondo uma visão ampla da utilização de novas tecnologias utilizadas para difusão da religião. Opto pelo estudo de caso, pois penso que permite uma melhor abordagem desse campo tecnológico.

  4. Otto Richard Gottlieb na UFRRJ

    OpenAIRE

    Raimundo Braz Filho; Universidade Estadual do Norte Fluminense Darcy Ribeiro; Mário Geraldo de Carvalho; Universidade Federal Rural do Rio de Janeiro

    2011-01-01

    Informações importantes da trajetória científica e produtiva do Prof. Otto Richard Gottlieb e sobre seu legado são revelados por dois de seus ex-alunos. Revelam sua perseverança na criação de grupos comprometidos com pesquisas em produtos naturais no Brasil. Inicialmente na Universidade de Brasília (UnB) e, em consequência de pressões políticas da década de sessenta, seu grupo deslocou-se para outras instituições recebendo apoio da Universidade Federal de Minas Gerais (UFMG), do Centro de Pes...

  5. Makosa Yanayofanywa na Wanafunzi Wanaojifunza Kiswahili kama ...

    African Journals Online (AJOL)

    Makala haya, yanashughulika na makosa ambayo hufanywa na wanafunzi wanaojifunza Kiswahili kama lugha ya pili katika shule za sekondari nchini Uganda. Mtafiti ameyaainisha makosa mbalimbali na kuyaeleza kiusahihi. Makala yanaeleza namna ambavyo makosa hayo hutokea. Yaani, kama ni makosa ...

  6. NA50 quark-gluon plasma experiment

    CERN Multimedia

    1997-01-01

    View of the NA50 detector, which studies quark-gluon plasma. The picture shows one of the six hodoscopes, made of 48 scintillator counters, used in the muon trigger of the NA50 spectrometer. The picture shows one of the six hodoscopes, made of 48 scintillator counters, used in the muon trigger of the NA50 spectrometer

  7. Pseudo-ternary phase diagram in the Na2O-Na2O2-NaOH system

    International Nuclear Information System (INIS)

    Saito, Jun-ichi; Tendo, Masayuki; Aoto, Kazumi

    1997-10-01

    Generally, the phase diagrams are always used to understand the present state of compounds at certain temperature. In order to understand the corrosion behavior of structural material for FBR by main sodium compounds (Na 2 O, Na 2 O 2 and NaOH), it is very important to comprehend the phase diagrams of their compounds. However, only Na 2 O-NaOH pseudo-binary phase diagram had been investigated previously in this system. There is no study of other pseudo-binary or ternary phase diagrams in the Na 2 O-Na 2 O 2 -NaOH system. In this study, in order to clarify the present states of their compounds at certain temperatures, the pseudo-binary and ternary phase diagrams in the Na 2 O-Na 2 O 2 -NaOH system were prepared. A series of thermal analyses with binary and ternary component system has been carried out using the differential scanning calorimetry (DSC). The liquidus temperature and ternary eutectic temperatures were confirmed by these measurements. The beneficial indications for constructing phase diagrams were obtained from these experiments. On the basis of these results, the interaction parameters between compounds which were utilized for the Thermo-Calc calculation were optimized. Thermo-Calc is one of thermodynamic calculation software. Consequently the accurate pseudo-binary and ternary phase diagrams were indicated using the optimized parameters. (author)

  8. Homocisteína Homocysteine

    Directory of Open Access Journals (Sweden)

    Lindalva Batista Neves

    2004-10-01

    Full Text Available A homocisteína, formada a partir da metionina hepática, é metabolizada nas vias de desmetilação e de transulfuração, sendo que seus valores plasmáticos e urinários refletem a síntese celular. Sua determinação, realizada em jejum e após sobrecarga de metionina, caracteriza as diferenças dessas vias metabólicas, principalmente quando de natureza genética. A hiper-homocisteinemia tem sido associada a maior risco de eventos aterotrombóticos, e a literatura sugere associação causal, independente de outros fatores de risco para doença arterial. Diminuição da homocisteína plasmática para valores normais é seguida de redução significante na incidência de doença aterotrombótica. A relação entre homocisteína e o fígado vem adquirindo importância nos dias atuais, uma vez que alterações das lipoproteínas e da depuração de metionina são comuns em pacientes com doença hepática crônica (hepatocelular e canalicular. O tratamento da hiper-homocisteinemia fundamenta-se na suplementação alimentar e medicamentosa de ácido fólico e vitaminas B6 e B12.Homocysteine, formed from hepatic methionine, is metabolized through the pathways of demethylation and transsulfuration. Its plasmatic and urinary values reflect the cell synthesis. Its determination after fasting and increased infusion of methionine shows the differences of these two metabolic pathways, mainly when it is related to genetic diseases. Hyperhomocysteinemia has been associated with a higher risk of vascular thrombotic events. Several authors suggest a causal relationship between these events independently of other risk factors for vascular diseases. Decrease in plasmatic homocysteine to normal levels is followed by a significant reduction on the incidence of vascular thrombotic events. The correlation between the liver and homocysteine is becoming more important because of the recent findings that alterations of lipoproteins and methionine clearance are

  9. Myocardial Na,K-ATPase: Clinical aspects

    OpenAIRE

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs...

  10. Istraživanje uticaja nekih parametara na osetljivost eksplozivnih materija na toplotni impuls

    OpenAIRE

    Jeremić Radun

    2002-01-01

    Ispitivana je osetljivost nekoliko vrsta eksplozivnih materija na toplotni impuls merenjem vremena zadrške u zavisnosti od temperature. Na osnovu eksperimentalnih rezultata određene su vrednosti energije aktivacije i predeksponencijalni faktori u jednačini Semjonova. Istraživan je i uticaj mase ispitivanog uzorka, granulacije i veličine kristala eksploziva na osetljivost na toplotni impuls. Pokazano je da ovi parametri imaju značajan uticaj na osetljivost eksplozivnih materija, pa je neophodn...

  11. Silicene for Na-ion battery applications

    KAUST Repository

    Zhu, Jiajie

    2016-08-19

    Na-ion batteries are promising candidates to replace Li-ion batteries in large scale applications because of the advantages in natural abundance and cost of Na. Silicene has potential as the anode in Li-ion batteries but so far has not received attention with respect to Na-ion batteries. In this context, freestanding silicene, a graphene-silicene-graphene heterostructure, and a graphene-silicene superlattice are investigated for possible application in Na-ion batteries, using first-principles calculations. The calculated Na capacities of 954mAh/g for freestanding silicene and 730mAh/g for the graphenesilicene superlattice (10% biaxial tensile strain) are highly competitive and potentials of >0.3 V against the Na/Na potential exceed the corresponding value of graphite. In addition, the diffusion barriers are predicted to be <0.3 eV.

  12. Hali ya taaluma ya ukalimani Tanzania: jana, leo na kesho ...

    African Journals Online (AJOL)

    Umuhimu wa ukalimani katika mawasiliano umeongezeka kutokana na utandawazi. Utandawazi umerahisisha kukutanika na kuwasiliana kwa watu wazungumzao lugha tofauti kupitia wakalimani. Kutokana na ongezeko hilo la umuhimu wa ukalimani, kumekuwa na jitihada mbalimbali katika nchi mbalimbali kuhakikisha ...

  13. Docência na universidade: professores inovadores na USP

    Directory of Open Access Journals (Sweden)

    Chamlian Helena Coharik

    2003-01-01

    Full Text Available O artigo trata de pesquisa realizada com um grupo de professores inovadores da Universidade de São Paulo tendo como objetivo procurar subsídios para a formação do professor universitário. Esses docentes foram entrevistados, solicitando que detalhassem melhor suas experiências inovadoras; explicassem as razões pelas quais haviam introduzido modificações em sua forma de trabalho; explicitassem as relações entre sua atividade de docência e de pesquisa, expressassem o papel que atribuíam ao ensino na universidade, bem como a forma pela qual sua trajetória acadêmica havia se cumprido até então. A diversidade de experiências relatadas e, ao mesmo tempo, a convergência de visões a respeito de suas funções de ensino e de pesquisa na universidade permitem-nos afirmar que, mais do que uma formação pedagógica específica, a sensibilização para as dificuldades do ensino e a valorização institucional dessa atividade consistiriam em grande avanço para a formação do professor.

  14. Na alvorada de um sport

    OpenAIRE

    Sartori, Carina

    2013-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-graduação em História, Florianópolis, 2013 Em Florianópolis, a primeira Sociedade de Regatas organizada, meados do século XIX, contaria com a participação dos Coronéis da Marinha e da Escola de Menores e Marinheiros da Canhoneira. Na virada do século, a fundação do Clube 29 de Abril permitiria que as atividades relacionadas ao Remo fossem oferecidas a todos que se associ...

  15. A Umbanda Portuguesa na Internet

    OpenAIRE

    Ismael Pordeus Júnior

    2004-01-01

    A partir de considerações sobre o processo de transculturação da Umbanda de Omolocô vou a propósito do grupo religioso do Terreiro de Umbanda Ogum Megê em Lisboa - Portugal discutir a textualização da memória. Como outras religiões que visam hoje o universal a Umbanda utiliza novas tecnologias disponíveis na Internet. Esse novo meio de comunicação favorece o processo de transculturação religiosa. Utilizando uma abordagem antropológica procuro realizar um estudo dos sites da Umbanda portuguesa...

  16. Relationship between intracellular Na+ concentration and reduced Na+ affinity in Na+,K+-ATPase mutants causing neurological disease

    DEFF Research Database (Denmark)

    Toustrup-Jensen, Mads Schak; Einholm, Anja P.; Schack, Vivien

    2014-01-01

    The neurological disorders familial hemiplegic migraine type 2 (FHM2), alternating hemiplegia of childhood (AHC), and rapid-onset dystonia parkinsonism (RDP) are caused by mutations of Na+,K+-ATPase α2- and α3-isoforms, expressed in glial and neuronal cells, respectively. Although these disorders......, addressing the question to what extent they cause a change of the intracellular Na+ and K+ concentrations ([Na+]i and [K+]i) in COS cells. C-terminal extension mutants generally showed dramatically reduced Na+ affinity without disturbance of K+ binding, as did other RDP mutants. No phosphorylation from ATP...... was observed for the +28 mutation of α2, despite a high expression level. A significant rise of [Na+]i and reduction of [K+]i was detected in cells expressing mutants with reduced Na+ affinity, and did not require a concomitant reduction of the maximal catalytic turnover rate or expression level. Moreover, two...

  17. O ATLETISMO NA PERSPECTIVA EDUCACIONAL

    Directory of Open Access Journals (Sweden)

    Leandro Araujo de Sousa

    2017-06-01

    Full Text Available A educação física escolar deve proporcionar experiências aos alunos para o seu desenvolvimento integral. As aulas muitas vezes são reduzidas ao ensino de esportes tradicionais, o que limita o repertório de movimentos dos alunos. Dessa forma o presente estudo de revisão objetiva problematizar o atletismo no ambiente escolar e propor possibilidades pedagógicas para seu ensino. Nesta pesquisa propomos tratar o ensino do atletismo na escola, caracterizando-o pelo seu repertório de movimentos que são naturais ao ser humano, como correr, saltar e lançar, o que possibilita maior praticidade em sua aplicação pedagógica, porém essas possibilidades não são consideradas no ambiente educacional. Diante dos dados encontrados, sugerimos que esse esporte seja abordado de forma multidimensional no ambiente escolar contextualizando-o à visão de algumas correntes teóricas. Nessa perspectiva do esporte educacional, o atletismo pode, assim como deve ser trabalhado nas aulas de educação física como instrumento pedagógico de ensino e auxiliar na formação do aluno de forma global.

  18. Identidades Homossexuais na Territorialidade Tradicionalista

    Directory of Open Access Journals (Sweden)

    Edipo Djavan dos Reis Göergen

    2015-12-01

    Full Text Available Este artigo apresenta o debate teórico que sustenta a pesquisa de mestrado desenvolvida pelo autor. Tendo por base suas vivências em contextos de tradicionalismo gaúcho, o autor deste trabalho tem percebido a grande quantidade de homossexuais, ou indivíduos que se auto-denominam não-heterossexuais, integrando as atividades artísticas do Movimento Tradicionalista Gaúcho, ou a territorialidade tradicionalista. Interessado em investigar tal fenômeno, o autor tem desenvolvido o projeto de pesquisa “Os Espaços Paradoxais de Relações Homoeróticas na Territorialidade Tradicionalista”, sob orientação do prof. Dr. Benhur Pinós da Costa, no Programa de Pós-Graduação em Geografia (UFSM. Para que essa pesquisa seja realizada, levam-se em conta as relações de gênero e de sexualidade que estão envolvidas no tema. Dessa forma, por ainda se tratarem de temáticas tidas como insignificantes na sociedade em geral e marginalizadas no campo científico, para que o presente trabalho fosse empreendido, buscou-se amparo teórico nas geografias feministas e queer, segmentos contemporâneos da ciência geográfica.

  19. Micotoxinas e Micotoxicoses na Avicultura

    Directory of Open Access Journals (Sweden)

    Santurio JM

    2000-01-01

    Full Text Available Esta revisão tem como objetivo principal mostrar, baseado em dezenas de pesquisas realizadas, os efeitos tóxicos das micotoxinas aflatoxinas, tricotecenos, zealenona e fumonisinas sobre o desempenho das aves. O descobrimento das propriedades hepatotóxicas e hepatocarcinogênicas de algumas linhagens de Aspergillus flavus e A. parasiticus em perus, na Inglaterra, no início da década de 1960, seguida pela elucidação da estrutura de seus metabólitos tóxicos, as aflatoxinas, deu novo enfoque e prioridade para a pesquisa sobre micotoxinas. Análises de aflatoxinas realizadas no Laboratório de Análises Micotoxicológicas (LAMIC da Universidade Fedaral de Santa Maria, entre os anos de 1986 e janeiro de 2000, em 15.600 amostras de alimentos destinados principalmente ao consumo animal, demonstram que no milho analisado, 41,9% das amostras estavam contaminadas por aflatoxinas. Em surtos de aflatoxicose no campo, uma das características mais marcantes é a má absorção que se manifesta como partículas de ração mal digeridas na excreta das aves. Também observa-se, em frangos e poedeiras que recebem AFL, extrema palidez das mucosas e pernas. Dietas deficientes em riboflavina ou colecalciferol (vit. D tornaram frangos sensíveis, nos índices de desenvolvimento corporal, a concentrações muito baixas de AFL. O efeito aflatoxina nos frangos é maior na fase inicial de crescimento, ou seja, quando as aves ingeriram aflatoxina nos primeiros 21 dias de vida, e quanto maior o nível de stress do lote, menor a quantidade de AFL para afetar negativamente seu desempenho, seja na produção de carne ou de ovos. As principais micotoxinas do grupo dos tricotecenos são: toxina T-2; deoxynivalenol (DON; diacetoxyscirpenol (DAS, todas produzidas através de diversas espécies de fungos do gênero Fusarium. Além dos tricotecenos, o fusarium também pode produzir zearalenona e fumonisinas. Dessas fusarium-toxinas, somente toxina T-2 gera patologias s

  20. Fotografia na Imprensa: conflitos na câmara escura

    Directory of Open Access Journals (Sweden)

    José Lúcio da Silva Menezes

    2014-07-01

    Full Text Available Este artigo recupera o teor ideológico do discurso que a Revista Veja elaborou sobre a classe trabalhadora que emergiu no cenário brasileiro, no final da década de 1970. O destaque dado aos trabalhadores como temática central resgatada, deve-se aos movimentos grevistas por eles encetados, após anos de ocultamento de sua resistência sob a repressão da ditadura civil-militar (1964-1985. Com a rebeldia operária, as matérias a respeito deste grupo, na Revista,foram se tornando mais constantes e visíveis, pois já não era mais possível, para a Revista Veja, ignorar a existência da classe operária que, com a força insurgente das greves, ocupava as ruas do Brasil.

  1. Vpliv toplotnih mostov na porabo energije za ogrevanje na primeru osnovne šole

    OpenAIRE

    Megušar, Primož

    2015-01-01

    Na primeru Osnovne šole Dobrova sem preveril, kakšen vpliv imajo dejanski toplotni mostovi na porabo energije za ogrevanje. Iz načrtov stavbe sem evidentiral vse toplotne mostove, kateri vplivajo na porabo energije. Tem toplotnim mostovom sem nato v standardu SIST EN ISO 14683 poiskal ustrezne približke. Nato sem s programom TOST izvedel tri simulacije. V prvem primeru toplotnih mostov nisem upošteval. V drugem primeru sem toplotne mostove upošteval na poenostavljen način, v zadnjem primeru p...

  2. Na and K dependence of the Na/K pump in cystic fibrosis fibroblasts.

    OpenAIRE

    Reznik, V M; Schneider, J A; Mendoza, S A

    1981-01-01

    The Na and K dependence of the Na/K pump was measured in skin fibroblasts from patients with cystic fibrosis and age/sex-matched controls. Under basal conditions, there was no difference between control and cystic fibrosis cells in protein per cell, intracellular Na and K content, or Na/K pump activity (measured as ouabain-sensitive 86Rb uptake). There was no difference in the Na dependence of the Na/K pump between cystic fibrosis cells and control cells. In cells from patients with cystic fi...

  3. Modification of single Na+ channels by batrachotoxin.

    Science.gov (United States)

    Quandt, F N; Narahashi, T

    1982-11-01

    The modifications in the properties of voltage-gated Na+ channels caused by batrachotoxin were studied by using the patch clamp method for measuring single channel currents from excised membranes of N1E-115 neuroblastoma cells. The toxin-modified open state of the Na+ channel has a decreased conductance in comparison to that of normal Na+ channels. The lifetime of the modified open state is drastically prolonged, and channels now continue to open during a maintained depolarization so that the probability of a channel being open becomes constant. Modified and normal open states of Na+ channels coexist in batrachotoxin-exposed membrane patches. Unlike the normal condition, Na+ channels exposed to batrachotoxin open spontaneously at large negative potentials. These spontaneous openings apparently cause the toxin-induced increase in Na+ permeability which, in turn, causes membrane depolarization.

  4. Low-spin states of 23Na

    International Nuclear Information System (INIS)

    Bakkum, E.L.

    1987-01-01

    A study of 23 Na via the 22 Ne(p,γ) 23 Na and 23 Na(γ,γ) 23 Na reactions is presented. Only a limited number of resonances has been studied, selected on the basis of strong excitation of the lowest levels of which the spin was unknown. As a result the spins are now known of all levels of 23 Na with excitation energies up to 7 MeV, except for a few high-spin states which are too weakly excited in the decay of the known 22 Ne(p,γ) resonances. The mean lifetimes of the 23 Na levels at 4.43 and 7.89 MeV were found to be 350±70 and 220±17 attoseconds (1 attosecond = 10 -18 seconds) respectively. 97 refs.; 22 figs.; 12 tabs

  5. Modification of single Na+ channels by batrachotoxin.

    OpenAIRE

    Quandt, F N; Narahashi, T

    1982-01-01

    The modifications in the properties of voltage-gated Na+ channels caused by batrachotoxin were studied by using the patch clamp method for measuring single channel currents from excised membranes of N1E-115 neuroblastoma cells. The toxin-modified open state of the Na+ channel has a decreased conductance in comparison to that of normal Na+ channels. The lifetime of the modified open state is drastically prolonged, and channels now continue to open during a maintained depolarization so that the...

  6. PRIMERJAVA GEODETSKIH METOD NA ZAHTEVNEM GRADBENEM OBJEKTU

    OpenAIRE

    Reberčnik, Matic

    2017-01-01

    V projektni nalogi smo v uvodnih poglavjih predstavili različne načine izvajanja geodetskih meritev, ki jih v gradbeništvu uporabljamo pri analizi pomikov in deformacij gradbenih konstrukcij ter terena, na katerem so le-te postavljene. V nadaljevanju opisujemo terestične in GNSS (globalni navigacijski satelitski sistem) metode, ki smo jih uporabljali pri izvajanju meritev na izbranem premostitvenem objektu avtocestnega odseka v Sloveniji (zaradi varovanja podatkov ga imenujemo Objekt 1). Pod...

  7. Ionic dependence of active Na-K transport: clamping of cellular Na+ with monensin

    International Nuclear Information System (INIS)

    Haber, R.S.; Pressley, T.A.; Loeb, J.N.; Ismail-Beigi, F.

    1987-01-01

    The Na + ionophore monensin was used to study the Na + - and K + -dependence of ouabain-inhibitable 86 Rb + uptake in ARL 15 cells, a rat liver cell line. Graded concentrations of monensin rapidly induced incremental elevations of cellular Na + that were stable for up to 2 h. In experiments in which cellular Na + was thus clamped at various levels, the activation curve for ouabain-inhibitable 86 Rb + uptake as a function of intracellular Na + was found to be steepest near basal Na + levels (Hill coefficient /congruent/ 2.4), indicating that these cells can respond to relatively large changes in passive Na + entry by increasing the rate of Na-K pump function with only minimal increases in cellular Na + . Exposure of cells to monensin also permitted examination of the extracellular-K + dependence of ouabain inhibitable 86 Rb + uptake in presence of saturating intracellular Na + and yielded a Hill coefficient of ∼ 1.5. The rate of ATP hydrolysis calculated from measurements of the maximal rate of ouabain-inhibitable 86 Rb + uptake in intact cells was similar to the enzymatic V/sub max/ of the Na + -K + -ATPase in cell lysates, suggesting that the Na + -K + -ATPase activity in these broken-cell preparations closely reflects the functional transport capacity of the Na-K pump

  8. Fabrication of implanted $^{22}$Na targets

    CERN Multimedia

    2002-01-01

    A knowledge of the $^{22}$Na(p,$\\gamma$)$^{23}$ Mg reaction rate is of significant astrophysical interest. In order to complete previous studies of this reaction, radioactive $^{22}$Na targets of high purity are required. We ask for support to fabricate these targets via the implantation technique at ISOLDE GPS (off—line mode) using $^{22}$Na nuclides in an Al matrix produced in Nov. 1990 at the PSI (Zürich). The $^{22}$Na nuclides are released and ionized in a surface ionisation source, mass-analyzed at ISOLDE GPS, and implanted in a Ni-Ta backing and a C—foil in a special implantation setup.

  9. OGLAŠEVANJE NA FACEBOOKU V SLOVENIJI

    OpenAIRE

    Dobnik, Monja

    2013-01-01

    Danes so zahvaljujoč napredni mobilni tehnologiji družbena omrežja z nami na vsakem koraku. Facebook (FB) se po priljubljenosti uvršča v sam vrh družbenih omrežij in glede na to, da ga uporablja že več kot milijarda zemljanov, ponuja tudi odlične trg za oglaševanje. To so ugotovili tudi slovenski podjetniki. V diplomski nalogi je predstavljeno, kako na FB oglašujejo nekatera slovenska podjetja, s pomočjo spletnega vprašalnika pa je ugotovljeno tudi, kaj o oglasih na FB menijo njegovi uporabni...

  10. Na+ Recirculation and Isosmotic Transport

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Møbjerg, N

    2006-01-01

    of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability...... external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely...... measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation...

  11. O consumo na vida digital

    Directory of Open Access Journals (Sweden)

    Iuri Yudi Furukita Baptista

    2016-02-01

    Full Text Available O modelo de consumo não possui as mesmas características sempre: suas relações, motivações, formatos, espaços, interesses e atividades são construções sociais que se modificam atreladas ao cenário econômico, político e tecnológico. O presente trabalho repassa o surgimento da sociedade do consumidor para então conjecturar sobre as propriedades distintivas do consumo na vida digital. O que se defende ao final é que o consumidor já não se restringe ao papel de consumir.

  12. Na+/Ca2+ exchange and Na+/K+-ATPase in the heart

    Science.gov (United States)

    Shattock, Michael J; Ottolia, Michela; Bers, Donald M; Blaustein, Mordecai P; Boguslavskyi, Andrii; Bossuyt, Julie; Bridge, John H B; Chen-Izu, Ye; Clancy, Colleen E; Edwards, Andrew; Goldhaber, Joshua; Kaplan, Jack; Lingrel, Jerry B; Pavlovic, Davor; Philipson, Kenneth; Sipido, Karin R; Xie, Zi-Jian

    2015-01-01

    This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na+/Ca2+ exchange (NCX) and Na+/K+-ATPase (NKA). While the relevance of Ca2+ homeostasis in cardiac function has been extensively investigated, the role of Na+ regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na+ content have multiple effects on the heart by influencing intracellular Ca2+ and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na+ homeostasis. Among the proteins that accomplish this task are the Na+/Ca2+ exchanger (NCX) and the Na+/K+ pump (NKA). By transporting three Na+ ions into the cytoplasm in exchange for one Ca2+ moved out, NCX is one of the main Na+ influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na+ ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na+ and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na+ homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na+/Ca2+ exchanger (NCX1) and Na+/K+ pump and the controversies that still persist in the field. PMID:25772291

  13. Analiza utjecaja stabilizatora na određivanje elemenata vanjske orijentacije kamere na bespilotnoj letjelici

    OpenAIRE

    Gašparović, Mateo; Gajski, Dubravko

    2016-01-01

    U radu su prikazani i interpretirani rezultati analize utjecaja stabilizatora kamere na određivanje elemenata vanjske orijentacije na bespilotnim letjelicama. Riječ je o 3-osnom stabilizatoru baziranom na elektromotorima bez četkica. Prikazan je i objašnjen koncept rada stabilizatora kamera na bespilotnim letjelicama. Za potrebe rada stabilizator je unaprijeđen upotrebom drugog inercijalnog mjernog uređaja (IMU). Provedena su dva testiranja stabilizatora upotrebom jednog i dva inercijalna mje...

  14. Na+,K+-ATPase Na+ affinity in rat skeletal muscle fiber types

    DEFF Research Database (Denmark)

    Kristensen, Michael; Juel, Carsten

    2010-01-01

    Previous studies in expression systems have found different ion activation of the Na(+)/K(+)-ATPase isozymes, which suggest that different muscles have different ion affinities. The rate of ATP hydrolysis was used to quantify Na(+),K(+)-ATPase activity, and the Na(+) affinity of Na(+),K(+)-ATPase......Previous studies in expression systems have found different ion activation of the Na(+)/K(+)-ATPase isozymes, which suggest that different muscles have different ion affinities. The rate of ATP hydrolysis was used to quantify Na(+),K(+)-ATPase activity, and the Na(+) affinity of Na......(+),K(+)-ATPase was studied in total membranes from rat muscle and purified membranes from muscle with different fiber types. The Na(+) affinity was higher (K(m) lower) in oxidative muscle compared with glycolytic muscle and in purified membranes from oxidative muscle compared with glycolytic muscle. Na......(+),K(+)-ATPase isoform analysis implied that heterodimers containing the beta(1) isoform have a higher Na(+) affinity than heterodimers containing the beta(2) isoform. Immunoprecipitation experiments demonstrated that dimers with alpha(1) are responsible for approximately 36% of the total Na,K-ATPase activity. Selective...

  15. Exploration of NaVOPO4 as a cathode for a Na-ion battery.

    Science.gov (United States)

    Song, Jie; Xu, Maowen; Wang, Long; Goodenough, John B

    2013-06-11

    Monoclinic NaVOPO4 is explored as a cathode material for a sodium ion battery. It exhibits electrochemical activity operating at an average potential of 3.6 V (vs. Na(+)/Na) and delivers a reversible capacity of 90 mA h g(-1) at 1/15 C.

  16. Study of the Na-C-O and Na-H-O ternary systems in the sodium rich corner

    International Nuclear Information System (INIS)

    Maupre, J.-P.

    1978-02-01

    The purpose of this study is to provide a contribution to the understanding of the sodium - carbon - oxygen and sodium - hydrogen - oxygen ternary systems in the sodium rich corner. In order to do this the Na-NaH-Na 2 O-NaOH phase diagram was completed and the Na-Na 2 O-Na 2 CO 3 -C phase diagram was outlined. This work is made up of two parts. The first is devoted to a critical literature survey essential to establish correct phase diagrams. The second is an experimental study followed by a discussion collating our finding to the literary data. The basic experimental technique used is differential thermal analysis (DTA) but it has been completed by quenching, X-ray and chemical analysis methods. The proposed phase diagrams imply that Na-NaH-Na 2 O-NaOH and Na-Na 2 O-Na 2 CO 3 -C systems are reciprocal ternary systems. Temperatures of stable pairs reversal are respectively 410 and 690 0 C. The stable pairs are Na-NaOH and Na-Na 2 CO 3 at elevated temperature, Na 2 O-NaH and Na 2 O-C at low temperature [fr

  17. OGLAŠEVANJE NA DRUŽBENIH OMREŽJIH NA PRIMERU FACEBOOKA

    OpenAIRE

    Novak, Martina

    2012-01-01

    V diplomskem delu obravnavamo družbene medije kot novo priložnost za promocijo in oglaševanje podjetij. Spoznali smo družbena omrežja na splošno in nekaj teh, ki jih uporabljamo tudi v Sloveniji na kratko predstavili. Podrobneje smo se osredotočili na družbeno omrežje Facebook, predvsem na samo spletno stran, njen izgled in storitve, ki jih ponuja uporabnikom. V nalogi je podrobneje opisan Facebook kot orodje za uporabo oglaševanja. Spoznali smo brezplačne in plačljive načine promocije in ogl...

  18. Extracellular Na+ levels regulate formation and activity of the NaX/alpha1-Na+/K+-ATPase complex in neuronal cells.

    Directory of Open Access Journals (Sweden)

    Emmanuelle eBerret

    2014-12-01

    Full Text Available MnPO neurons play a critical role in hydromineral homeostasis regulation by acting as sensors of extracellular sodium concentration ([Na+]out. The mechanism underlying Na+-sensing involves Na+-flow through the NaX channel, directly regulated by the Na+/K+-ATPase α1-isoform which controls Na+-influx by modulating channel permeability. Together, these two partners form a complex involved in the regulation of intracellular sodium ([Na+]in. Here we aim to determine whether environmental changes in Na+ could actively modulate the NaX/Na+/K+-ATPase complex activity.We investigated the complex activity using patch-clamp recordings from rat MnPO neurons and Neuro2a cells. When the rats were fed with a high-salt-diet, or the [Na+] in the culture medium was increased, the activity of the complex was up-regulated. In contrast, drop in environmental [Na+] decreased the activity of the complex. Interestingly under hypernatremic condition, the colocalization rate and protein level of both partners were up-regulated. Under hyponatremic condition, only NaX protein expression was increased and the level of NaX/Na+/K+-ATPase remained unaltered. This unbalance between NaX and Na+/K+-ATPase pump proportion would induce a bigger portion of Na+/K+-ATPase-control-free NaX channel. Thus we suggest that hypernatremic environment increases NaX/Na+/K+-ATPase α1-isoform activity by increasing the number of both partners and their colocalization rate, whereas hyponatremic environment down-regulates complex activity via a decrease in the relative number of NaX channels controlled by the pump.

  19. K+ congeners that do not compromise Na+ activation of the Na+,K+-ATPase

    DEFF Research Database (Denmark)

    Mahmmoud, Yasser A; Kopec, Wojciech; Khandelia, Himanshu

    2015-01-01

    to no antagonism to cytoplasmic Na(+) activation. Na(+),K(+)-ATPase structures revealed a previously undescribed rotamer transition of the hydroxymethyl side chain of the absolutely conserved Thr(772) of the α-subunit. The side chain contributes its hydroxyl to Na(+) in site I in the E1 form and rotates......The Na(+),K(+)-ATPase is essential for ionic homeostasis in animal cells. The dephosphoenzyme contains Na(+) selective inward facing sites, whereas the phosphoenzyme contains K(+) selective outward facing sites. Under normal physiological conditions, K(+) inhibits cytoplasmic Na(+) activation...... to contribute its methyl group toward K(+) in the E2 form. Molecular dynamics simulations to the E1·AlF4 (-)·ADP·3Na(+) structure indicated that 1) bound organic cations differentially distorted the ion binding sites, 2) the hydroxymethyl of Thr(772) rotates to stabilize bound Form(+) through water molecules...

  20. Crystal structure of Na+, K(+)-ATPase in the Na(+)-bound state.

    Science.gov (United States)

    Nyblom, Maria; Poulsen, Hanne; Gourdon, Pontus; Reinhard, Linda; Andersson, Magnus; Lindahl, Erik; Fedosova, Natalya; Nissen, Poul

    2013-10-04

    The Na(+), K(+)-adenosine triphosphatase (ATPase) maintains the electrochemical gradients of Na(+) and K(+) across the plasma membrane--a prerequisite for electrical excitability and secondary transport. Hitherto, structural information has been limited to K(+)-bound or ouabain-blocked forms. We present the crystal structure of a Na(+)-bound Na(+), K(+)-ATPase as determined at 4.3 Å resolution. Compared with the K(+)-bound form, large conformational changes are observed in the α subunit whereas the β and γ subunit structures are maintained. The locations of the three Na(+) sites are indicated with the unique site III at the recently suggested IIIb, as further supported by electrophysiological studies on leak currents. Extracellular release of the third Na(+) from IIIb through IIIa, followed by exchange of Na(+) for K(+) at sites I and II, is suggested.

  1. LEITURA E LEITURA NA UNIVERSIDADE

    Directory of Open Access Journals (Sweden)

    Profª Drª Márcia A. G. Molina

    2015-12-01

    Full Text Available O texto apresenta uma discussão acerca da leitura, traçando, primeiramente, um percurso histórico dessa questão, iniciando-se no XIX aqui no Brasil.. Na sequência, aponta-se para a importância daquele que trabalha com a leitura ter paixão por ela, para que possa formar sujeitos também apaixonados pelo ato de ler. Continua mostrando os tipos de leitura, de acordo com FREIRE (1989, KOCK e ELIAS (2006 e apontando as atuais orientações para os procedimentos de leitura de um texto, baseados em KLEIMAN (2002. Conclui-se que, para formar o bom leitor, entendido como aquele que lê o não-dito e caminha para além da paráfrase reprodutiva, deve-se: ter paixão pela leitura, orientar os estudantes para essa prática, estabelecendo-se objetivos de leitura e reconhecer as estratégias que compreendem essa atividade.

  2. Necessidades da vida na morte

    Directory of Open Access Journals (Sweden)

    Denise Stefanoni Combinato

    2017-04-01

    Full Text Available Em função do envelhecimento populacional e aumento de doenças crônicas não transmissíveis, a Estratégia Saúde da Família (ESF tem se deparado com as necessidades das pessoas em processo de morte. A partir da análise do trabalho de profissionais da saúde que cuidaram de pessoas em processo de morte, o objetivo deste artigo é discutir as necessidades de saúde nesse processo, a fim de subsidiar o trabalho com essa população, especialmente na Atenção Primária à Saúde. Participaram da entrevista, após serem selecionados por dois questionários, onze profissionais (enfermeiros e médicos da ESF de Campinas/SP. A análise de dados foi pautada no referencial teórico-metodológico da Psicologia histórico-cultural. Como resultado, tem-se que as necessidades dos pacientes e familiares não são restritas ao momento de vida (proximidade da morte, mas referem-se, também, às condições de vulnerabilidade social.

  3. Terapia de linguagem na afasia

    Directory of Open Access Journals (Sweden)

    Mauro Spinelli

    1977-12-01

    Full Text Available A terapia da linguagem na afasia foi estudada em 15 pacientes, 8 do sexo masculino e 7 do sexo feminino; a idade variou de menos de 10 anos a mais de 50 anos; em 11 casos a afasia era sequela de acidente vascular cerebral e, em 4, de traumatismo crânio-encefálico. Quanto ao tipo de afasia, 5 pacientes apresentavam déficits predominantemente de expressão e 10 apresentavam déficits receptivos e expressivos em graus equiparáveis. Em 6 casos a terapia foi iniciada dentro dos 3 primeiros meses de instalação do quadro; nos restantes foi iniciada mais tardiamente. Dos 15 pacientes, 11 apresentaram evolução satisfatória, a qual não depndeu do grau de afasia, do tipo de afasia, da idade do paciente, do tipo de patologia e do intervalo entre a instalação do quadro afásico e o início da terapia. A terapia da linguagem no paciente afásico é efetiva, o prognóstico não pode ser feito a priori. Somente a evolução do caso com sua retestagem criteriosa poderá dar dados realmente úteis para se falar em evolução.

  4. Liquido cefalorraquiano na cisticercose encefalica

    Directory of Open Access Journals (Sweden)

    João Baptista dos Reis

    1979-06-01

    Full Text Available Foi feito um estudo do comportamento do líquido cefalorraquiano (LCR na cisticercose encefálica, com base em 656 observações retiradas de um material constituído por 120.000 exames de pacientes neurológicos e psiquiátricos, reunidas em 35 anos de trabalho. Com base nos casos comprovados por necrópsia ou cirurgia foram descritas as alterações do LCR. O estudo consecutivo de amostras de LCR obtidas em anos sucessivos, durante o decurso da doença, mostrou a persistência das alterações em numerosos casos, mesmo depois de 4 a 18 anos de observação. A reação de fixação de complemento para cisticerco permaneceu positiva durante todos estes anos. Foram também apreciadas as modificações do LCR em casos de cisticercose sub-cutânea e do globo ocular e em casos com cisticercos calcificados no encéfalo.

  5. Barroco: A tempestade na Biblioteca

    Directory of Open Access Journals (Sweden)

    Diego Cervelin

    2008-10-01

    Full Text Available http://dx.doi.org/10.5007/1984-784x.2008v8n12p167 Desde que Heinrich Wölfflin, nos últimos vinte anos do século XIX, se interessou por trazer à tona as formas arquitetônicas do século XVII conferindo-lhes caráter autônomo de estilo histórico determinável, não é nenhuma novidade que os estudos sobre o barroco pudessem polarizar – quase sempre em um tom colérico – os pesquisadores da arte e da cultura. Em terras do Brasil, não chega a ser de todo descabido recordar a severíssima crítica operada por Sérgio Buarque de Holanda em Raízes do Brasil. O livro, que pretende detectar a avalanche de equívocos que teria povoado o passado nacional com as vistas voltadas para a concretização de um projeto de emancipação e progresso na linha da história brasileira, apresenta em seu quarto capítulo uma impugnação explícita ao passado colonial.

  6. Barroco: A tempestade na Biblioteca

    Directory of Open Access Journals (Sweden)

    Diego Cervelin

    2008-12-01

    Full Text Available Desde que Heinrich Wölfflin, nos últimos vinte anos do século XIX, se interessou por trazer à tona as formas arquitetônicas do século XVII conferindo-lhes caráter autônomo de estilo histórico determinável, não é nenhuma novidade que os estudos sobre o barroco pudessem polarizar – quase sempre em um tom colérico – os pesquisadores da arte e da cultura. Em terras do Brasil, não chega a ser de todo descabido recordar a severíssima crítica operada por Sérgio Buarque de Holanda em Raízes do Brasil. O livro, que pretende detectar a avalanche de equívocos que teria povoado o passado nacional com as vistas voltadas para a concretização de um projeto de emancipação e progresso na linha da história brasileira, apresenta em seu quarto capítulo uma impugnação explícita ao passado colonial.

  7. Gasotransmitters: Novel regulators of epithelial Na+ transport?

    Directory of Open Access Journals (Sweden)

    Mike eAlthaus

    2012-04-01

    Full Text Available The vectorial transport of Na+ across epithelia is crucial for the maintenance of Na+ and water homeostasis in organs such as the kidneys, lung or intestine. Dysregulated Na+ transport processes are associated with various human diseases such as hypertension, the salt-wasting syndrome pseudohypoaldosteronism type 1, pulmonary edema, cystic fibrosis or intestinal disorders, which indicate that a precise regulation of epithelial Na+ transport is essential. Novel regulatory signaling molecules are gasotransmitters. There are currently three known gasotransmitters: nitric oxide (NO, carbon monoxide (CO and hydrogen sulfide (H2S. These molecules are endogenously produced in mammalian cells by specific enzymes and have been shown to regulate various physiological processes. There is a growing body of evidence, which indicates that gasotransmitters may also regulate Na+ transport across epithelia. This review will summarize the available data concerning NO, CO and H2S dependent regulation of epithelial Na+ transport processes and will discuss whether or not these mediators can be considered as true physiological regulators of epithelial Na+ transport biology.

  8. NMR studies on Na+ transport in Synechococcus PCC 6311

    Science.gov (United States)

    Nitschmann, W. H.; Packer, L.

    1992-01-01

    The freshwater cyanobacterium Synechococcus PCC 6311 is able to adapt to grow after sudden exposure to salt (NaCl) stress. We have investigated the mechanism of Na+ transport in these cells during adaptation to high salinity. Na+ influx under dark aerobic conditions occurred independently of delta pH or delta psi across the cytoplasmic membrane, ATPase activity, and respiratory electron transport. These findings are consistent with the existence of Na+/monovalent anion cotransport or simultaneous Na+/H+ +anion/OH- exchange. Na+ influx was dependent on Cl-, Br-, NO3-, or NO2-. No Na+ uptake occurred after addition of NaI, NaHCO3, or Na2SO4. Na+ extrusion was absolutely dependent on delta pH and on an ATPase activity and/or on respiratory electron transport. This indicates that Na+ extrusion via Na+/H+ exchange is driven by primary H+ pumps in the cytoplasmic membrane. Cells grown for 4 days in 0.5 m NaCl medium, "salt-grown cells," differ from control cells by a lower maximum velocity of Na+ influx and by lower steady-state ratios of [Na+]in/[Na+]out. These results indicate that cells grown in high-salt medium increase their capacity to extrude Na+. During salt adaptation Na+ extrusion driven by respiratory electron transport increased from about 15 to 50%.

  9. Na/K pump inactivation, subsarcolemmal Na measurements, and cytoplasmic ion turnover kinetics contradict restricted Na spaces in murine cardiac myocytes

    OpenAIRE

    Lu, Fang-Min; Hilgemann, Donald W.

    2017-01-01

    The Na/K pump exports cytoplasmic Na ions while importing K ions, and its activity is thought to be affected by restricted intracellular Na diffusion in cardiac myocytes. Lu and Hilgemann find instead that the pump can enter an inactivated state and that inactivation can be relieved by cytoplasmic Na.

  10. Fotokromne tiskarske barve na osnovi resorufina

    OpenAIRE

    Drnovšek, Petra

    2017-01-01

    Pametni materiali pod vplivom zunanjega dejavnika na predvidljiv in navadno uporaben način spremenijo svoje lastnosti. Takšni materiali so fotokatalitsko aktivne tiskarske barve, pri katerih se pod vplivom ultravijoličnega sevanja (v nadaljevanju UV) in/ali vidne svetlobe sproži fotokataliza, čemur sledi sprememba barve. Ena izmed možnih aplikacij fotokatalitsko aktivnih tiskarskih barv je ta, da uporabnika s spremembo barve opozarjajo na količino izpostavljenosti potencialno škodljivemu UV s...

  11. Pretpostavke za valorizaciju zapisa na elektronskim medijima

    OpenAIRE

    Eržišnik, Davorin

    1999-01-01

    U napisu se raspravlja o razlozima za valorizaciju zapisa na elektronskim medijima. Oni su ujedno i pretpostavke za tu valorizaciju, jer da bi ona uoće provodila, moraju postojati i razlozi. Istraživanje se bazira na usporedbi izmedju tih zapisa s jedne strane te klasičnih dokumenata i mikrofilmskih zapisa, s druge. Zaključuje se da u odnosu na tu drugu stranu, elektronski zapisi moraju imati i neke dodatne prednosti i kvalitete. U protivnom, ni ta valorizacija ne bi imala smisla.

  12. Naša eko hrana

    OpenAIRE

    Kelnerić, Tatjana

    2013-01-01

    Zdrav način življenja trajna je zadaća održivog razvoja i može se reći da ne postoji dobna granica za početak takvog načina života. U tom kontekstu neizbježno je da cilj svakog odgojno-obrazovnog rada, bilo da je riječ o projektu ili svakodnevici jedne odgojno-obrazovne skupine u dječjem vrtiću, mora biti usmjeren na čisto i zdravo okruženje, neposredan kontakt djeteta s prirodom, pravilnu prehranu i kretanje.

  13. VPLIV TEHNOLOŠKIH SPREMEMB NA GLOBALIZACIJO

    OpenAIRE

    Mohar, Nives

    2015-01-01

    Magistrsko delo z naslovom »Vpliv tehnoloških dejavnikov na globalizacijo« zajema dve večji področji ekonomske teorije – tehnologijo in globalizacijo. Namen magistrskega dela je analizirati odnose med tehnološkimi spremembami, gospodarsko rastjo in globaliziranostjo držav. Teoretični del smo razdelili na obravnavo tehnologije in globalizacije. Najprej smo predstavili pojme, ki se navezujejo na tehnologijo, nato smo prikazali mesto tehnologije skozi zgodovino ekonomske teorije in predstavi...

  14. Na+,K+ pumpen vedbliver at overraske

    DEFF Research Database (Denmark)

    Vilsen, Bente

    2008-01-01

    This article provides an overview of news about the Na+,K+ pump, an indispensable enzyme whose protein structure has been described in a recent article in Nature, 50 years after its discovery. In combination with mutational analysis, the structure reveals the binding pocket for the K+ ions...... and the regulation of Na+ transport by a strategically located C-terminus of the protein. Focus is also on the pathophysiology of two neurological disorders, familial hemiplegic migraine and rapid-onset dystonia-parkinsonism, recently shown to be caused by mutations in the Na+,K+-ATPase. Udgivelsesdato: may 19...

  15. Myocardial Na,K-ATPase: Clinical aspects

    Science.gov (United States)

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs used for the treatment of heart failure. Thus, potassium loss during diuretic therapy has been found to reduce myocardial Na,K-ATPase, whereas angiotensin-converting enzyme inhibitors may stimulate Na,K pump activity. Furthermore, hyperaldosteronism induced by heart failure has been found to decrease Na,K-ATPase activity. Accordingly, treatment with the aldosterone antagonist, spironolactone, may also influence Na,K-ATPase activity. The importance of Na,K pump modulation with heart disease, inhibition in digitalization and other effects of medication should be considered in the context of sodium, potassium and calcium regulation. It is recommended that digoxin be administered to heart failure patients who, after institution of mortality-reducing therapy, still have heart failure symptoms, and that the therapy be continued if symptoms are revealed or reduced. Digitalis glycosides are the only safe inotropic drugs for oral use that improve hemodynamics in heart failure. An important aspect of myocardial Na,K pump affection in heart disease is its influence on extracellular potassium (Ke) homeostasis. Two important aspects should be considered: potassium handling among myocytes, and effects of potassium entering the extracellular space of the heart via the bloodstream. It should be noted that both of these aspects of Ke homeostasis are affected by regulatory aspects, eg, regulation of the Na,K pump by physiological and pathophysiological conditions, as well as by medical

  16. Prepoznavanje spolnega nadlegovanja na delovnem mestu v zdravstvu

    OpenAIRE

    Lešnik, Tina

    2013-01-01

    Diplomsko delo predstavlja problem spolnega nadlegovanja na delovnem mestu na podlagi slovenske in tuje teorije ter se osredotoča na ugotavljanje pojava spolnega nadlegovanja na delovnem mestu v zdravstvu. Izhodišča: Dosedanje raziskave nasilja in spolnega nadlegovanja na delovnem mestu kažejo, da so zdravstveni delavci le temu izpostavljeni bolj kot delavci v drugih panogah. V okviru diplomskega dela smo raziskali prepoznavanje in pojavnost spolnega nadlegovanja na delovnem mestu med štu...

  17. Glutathionylation-Dependence of Na+-K+-Pump Currents Can Mimic Reduced Subsarcolemmal Na+ Diffusion

    Science.gov (United States)

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J.; Rasmussen, Helge H.

    2016-01-01

    The existence of a subsarcolemmal space with restricted diffusion for Na+ in cardiac myocytes has been inferred from a transient peak electrogenic Na+-K+ pump current beyond steady state on reexposure of myocytes to K+ after a period of exposure to K+-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na+ that accumulated in the diffusion-restricted space during pump inhibition in K+-free extracellular solution. However, there are no known physical barriers that account for such restricted Na+ diffusion, and we examined if changes of activity of the Na+-K+ pump itself cause the transient peak current. Reexposure to K+ reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na+ concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K+-free pipette solution could not be reconciled with restricted subsarcolemmal Na+ diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na+- and K+ concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na+-K+ pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na+-K+ pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K+-induced peak Na+-K+ pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K+-induced peak Na+-K+ pump current reflects the effect of conformation-dependent β1 pump subunit

  18. Altered Na+ transport after an intracellular alpha-subunit deletion reveals strict external sequential release of Na+ from the Na/K pump.

    Science.gov (United States)

    Yaragatupalli, Siddhartha; Olivera, J Fernando; Gatto, Craig; Artigas, Pablo

    2009-09-08

    The Na/K pump actively exports 3 Na(+) in exchange for 2 K(+) across the plasmalemma of animal cells. As in other P-type ATPases, pump function is more effective when the relative affinity for transported ions is altered as the ion binding sites alternate between opposite sides of the membrane. Deletion of the five C-terminal residues from the alpha-subunit diminishes internal Na(+) (Na(i)(+)) affinity approximately 25-fold [Morth et al. (2007) Nature 450:1043-1049]. Because external Na(+) (Na(o)(+)) binding is voltage-dependent, we studied the reactions involving this process by using two-electrode and inside-out patch voltage clamp in normal and truncated (DeltaKESYY) Xenopus-alpha1 pumps expressed in oocytes. We observed that DeltaKESYY (i) decreased both Na(o)(+) and Na(i)(+) apparent affinities in the absence of K(o)(+), and (ii) did not affect apparent Na(o)(+) affinity at high K(o)(+). These results support a model of strict sequential external release of Na(+) ions, where the Na(+)-exclusive site releases Na(+) before the sites shared with K(+) and the DeltaKESYY deletion only reduces Na(o)(+) affinity at the shared sites. Moreover, at nonsaturating K(o)(+), DeltaKESYY induced an inward flow of Na(+) through Na/K pumps at negative potentials. Guanidinium(+) can also permeate truncated pumps, whereas N-methyl-D-glucamine cannot. Because guanidinium(o)(+) can also traverse normal Na/K pumps in the absence of both Na(o)(+) and K(o)(+) and can also inhibit Na/K pump currents in a Na(+)-like voltage-dependent manner, we conclude that the normal pathway transited by the first externally released Na(+) is large enough to accommodate guanidinium(+).

  19. Painful Na-channelopathies: an expanding universe.

    Science.gov (United States)

    Waxman, Stephen G

    2013-07-01

    The universe of painful Na-channelopathies--human disorders caused by mutations in voltage-gated sodium channels--has recently expanded in three dimensions. We now know that mutations of sodium channels cause not only rare genetic 'model disorders' such as inherited erythromelalgia and channelopathy-associated insensitivity to pain but also common painful neuropathies. We have learned that mutations of NaV1.8, as well as mutations of NaV1.7, can cause painful Na-channelopathies. Moreover, recent studies combining atomic level structural models and pharmacogenomics suggest that the goal of genomically guided pain therapy may not be unrealistic. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Erythrocyte 22Na+ influx in hypertension

    International Nuclear Information System (INIS)

    Shalev, O.; Eaton, J.W.; Ben-Ishay, D.

    1984-01-01

    We assessed 22Na+ uptake by erythrocytes (RBC) from 38 individuals with essential hypertension and 37 healthy controls. All subjects were male, white, non-obese and with normal renal function, obviating sex, race, hormonal, ponderal and renal factors known to influence RBC Na+ handling. The mean +/- sem 22Na+ uptake of the patients was 284 +/- 16 mumole/liter RBC/hour while that of normal controls was 249 +/- 11 mumole/liter RBC/hour; although the difference reached borderline significance, individual values showed considerable overlap. Consequently, in our population, RBC 22Na+ uptake is not a reliable marker for essential hypertension. We believe that previous studies should be reassessed with regard to patients' characteristics and future studies employ rigorous criteria in selection of subjects

  1. Na+-H+ exchange and Na+-dependent transport systems in streptozotocin diabetic rat kidneys

    International Nuclear Information System (INIS)

    El-Seifi, S.; Freiberg, J.M.; Kinsella, F.J.; Cheng, L.; Sacktor, B.

    1987-01-01

    The streptozotocin-induced diabetic rat was used to test the hypothesis that Na + -H + exchange activity in the proximal tubule luminal membrane would be increased in association with renal hypertrophy, altered glomerular hemodynamics, enhanced filtered load and tubular reabsorption of 22 Na + , and stimulated 22 Na= pump activity in the basolateral membrane, previously reported characteristics of this experimental animal model. Amiloride-sensitive H + gradient-dependent Na + uptake and Na + gradient-dependent H + flux were increased in brush-border membrane vesicles from the streptozotocin-treated animals. Na + gradient-dependent uptakes of phosphate, D-glucose, L-proline, and myoinositol were decreased in the drug-induced diabetic animals. These membrane transport alterations were not found when the streptozotocin-diabetic animals were treated with insulin

  2. Perfil nutricional na artrite reumatoide

    Directory of Open Access Journals (Sweden)

    Rachel Simone Maccarini Zarpellon

    2014-01-01

    Full Text Available Objetivo: Estudar o perfil nutricional de pacientes com artrite reumatoide (AR. Métodos: Estudo transversal observacional de 102 pacientes com AR. Os pacientes foram estudados para dados clínicos, demográficos, sorológicos, atividade de doença e perfil nutricional. Neste último incluiu-se a medida do índice de massa corporal (IMC, relação quadril/cintura, pregas cutâneas bicipitais (PCB e sua adequação; prega cutânea tricipital (PCT e sua adequação e circunferência muscular do braço (CMB e sua adequação. Estudos de associação foram feitos usando os testes de Fisher e qui-quadrado para dados nominais e teste t não pareado e Mann Whitney para dados numéricos. Para cálculo de correlação usou-se o teste de Spearman. Resultado: Na amostra existiam 14/102 homens e 88/102 mulheres com idade média de 52,1 ± 11,5 anos e duração média de doença de 10,6 ± 7,4 anos. A relação cintura/quadril média era de 0,92 ± 0,07. De acordo com IMC, 30,3% tinham peso normal e 65,5% tinham peso acima do normal. De acordo com PCB, 74,5% eram normais e 25,5% tinham depleção; de acordo com a PCT, 83,3% eram normais e 16,7% tinham depleção. Associação de variáveis nutricionais com gênero, fator reumatoide, nódulos e atividade da doença não mostraram diferenças (p = NS exceto, por uma relação cintura/quadril menor em indivíduos com nódulos (p = 0,02 e uma correlação modesta da PCT com a duração de doença (p = 0,02; R = 0,22; 95% IC = 0,01-0,40. Conclusão: Existe uma alta prevalência de sobrepeso e obesidade em artrite reumatoide e uma pequena frequência de depleção muscular.

  3. Glutathionylation-Dependence of Na+-K+-Pump Currents Can Mimic Reduced Subsarcolemmal Na+ Diffusion

    OpenAIRE

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald?J.; Rasmussen, Helge?H.

    2016-01-01

    The existence of a subsarcolemmal space with restricted diffusion for Na+ in cardiac myocytes has been inferred from a transient peak electrogenic Na+-K+ pump current beyond steady state on reexposure of myocytes to K+ after a period of exposure to K+-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na+ that accumulated in the diffusion-restricted space during pump inhibition in K+-free extracellular solution. However, there are no know...

  4. Theoretical study of Na(4p2P)+Na(3s2S) and Cd(5p3P0)+Na(3s2S) collisions and their role in the energy transfer between Cd* and Na

    International Nuclear Information System (INIS)

    Magnier, S.; Pisa Univ.; Angeli, C.; Granucci, G.; Masnou-Seeuws, F.; Allegrini, M.; Pisa Univ.; Persico, M.

    1997-01-01

    We have computed the cross sections for the energy transfer process Cd(5p 3 P 0 ) + Na(3s 2 S) →Cd(5s 1 S) + Na(4p 2 P) and for the state changing collision Na(4p 2 P) + Na(3s 2 S)→Na(3d 2 D) + Na(3s 2 S), based on theoretical interaction potentials for the NaCd and Na 2 systems, respectively. Our calculations shed light on the interpretation of experiments with laser excited Na+Cd vapour mixtures. It turns out that Cd(5p 3 P 0 ), in rapid equilibrium with the doorway state Cd(5p 3 P 1 ), efficiently transfers energy to Na, populating the 4p 2 P state. The collisions with ground state Na cause a very fast conversion of the 4p 2 P to the 3d 2 D state, from which the strongest emission is observed. (orig.)

  5. Suppression of Na interstitials in Na-F codoped ZnO

    Science.gov (United States)

    Huo, Wenxing; Mei, Zengxia; Tang, Aihua; Liang, Huili; Du, Xiaolong

    2018-04-01

    Controlling the formation of interstitial Na (Nai) self-compensating defects has been a long-term physics problem for effective Na doping in ZnO. Herein, we present an experimental approach to the suppression of Nai defects in ZnO via Na and F codoping under an oxygen-rich condition during the molecular beam epitaxy growth process. It is found that the incorporation of such large numbers of Na and F dopants (˜1020 cm-3) does not cause an obvious influence on the lattice parameters. Hall-effect measurements demonstrate that F doping efficiently raises the Fermi level (EF) of ZnO films, which is expected to make the formation energy of Nai and NaZn increase and decrease, respectively. Most of the Na atoms occupy the substitutional Zn sites, and the formation of Nai is suppressed consequently. Secondary ion mass spectrometry measurements reveal that F and Na atoms are tightly bonded together due to their strong Coulomb interaction. The enhanced deep level emission (DLE) in ZnO:Na-F is ascribed to the considerable amount of isolated Zn vacancy (VZn) defects induced by the elevated EF and the formation of neutral (" separators="| FO + - Na Zn - ) 0 complexes. On the other hand, formation of (" separators="| FO + - VZn 2 - ) - complexes in ZnO:F exhausts most of the isolated Zn vacancies, leading to the disappearance of the DLE band.

  6. Absolute quantification of Na + bound fraction by double-quantum filtered 23Na NMR spectroscopy

    Science.gov (United States)

    Mouaddab, Mohamed; Foucat, Loïc; Donnat, Jean Pierre; Renou, Jean Pierre; Bonny, Jean Marie

    2007-11-01

    A method is described for the absolute quantification of double-quantum filtered spectra of spin-3/2 nuclei ( 23Na). The method was tested on a model system, a cationic exchange resin for which the number of Na + binding sites was quantitatively controlled. The theoretical and experimental approaches were validated on samples with different Na + concentrations. An excellent agreement between the results obtained by double-quantum and single-quantum acquisitions was found. This method paves the way for absolute quantification of both bound and free fractions of Na +, which are determining factors in the characterization of salted/brined/dried food products.

  7. Interaction between Na+/K+-pump and Na+/Ca2+-exchanger modulates intercellular communication.

    Science.gov (United States)

    Matchkov, Vladimir V; Gustafsson, Helena; Rahman, Awahan; Briggs Boedtkjer, Donna M; Gorintin, Sarah; Hansen, Anne Kirstine; Bouzinova, Elena V; Praetorius, Helle A; Aalkjaer, Christian; Nilsson, Holger

    2007-04-13

    Ouabain, a specific inhibitor of the Na(+)/K(+)-pump, has previously been shown to interfere with intercellular communication. Here we test the hypothesis that the communication between vascular smooth muscle cells is regulated through an interaction between the Na(+)/K(+)-pump and the Na(+)/Ca(2+)-exchanger leading to an increase in the intracellular calcium concentration ([Ca(2+)](i)) in discrete areas near the plasma membrane. [Ca(2+)](i) in smooth muscle cells was imaged in cultured rat aortic smooth muscle cell pairs (A7r5) and in rat mesenteric small artery segments simultaneously with force. In A7r5 coupling between cells was estimated by measuring membrane capacitance. Smooth muscle cells were uncoupled when the Na(+)/K(+)-pump was inhibited either by a low concentration of ouabain, which also caused a localized increase of [Ca(2+)](i) near the membrane, or by ATP depletion. Reduction of Na(+)/K(+)-pump activity by removal of extracellular potassium ([K(+)](o)) also uncoupled cells, but only after inhibition of K(ATP) channels. Inhibition of the Na(+)/Ca(2+)-exchange activity by SEA0400 or by a reduction of the equilibrium potential (making it more negative) also uncoupled the cells. Depletion of intracellular Na(+) and clamping of [Ca(2+)](i) at low concentrations prevented the uncoupling. The experiments suggest that the Na(+)/K(+)-pump may affect gap junction conductivity via localized changes in [Ca(2+)](i) through modulation of Na(+)/Ca(2+)-exchanger activity.

  8. HCO3(-)-coupled Na+ influx is a major determinant of Na+ turnover and Na+/K+ pump activity in rat hepatocytes

    International Nuclear Information System (INIS)

    Fitz, J.G.; Lidofsky, S.D.; Weisiger, R.A.; Xie, M.H.; Cochran, M.; Grotmol, T.; Scharschmidt, B.F.

    1991-01-01

    Recent studies in hepatocytes indicate that Na(+)-coupled HCO3- transport contributes importantly to regulation of intracellular pH and membrane HCO3- transport. However, the direction of net coupled Na+ and HCO3- movement and the effect of HCO3- on Na+ turnover and Na+/K+ pump activity are not known. In these studies, the effect of HCO3- on Na+ influx and turnover were measured in primary rat hepatocyte cultures with 22Na+, and [Na+]i was measured in single hepatocytes using the Na(+)-sensitive fluorochrome SBFI. Na+/K+ pump activity was measured in intact perfused rat liver and hepatocyte monolayers as Na(+)-dependent or ouabain-suppressible 86Rb uptake, and was measured in single hepatocytes as the effect of transient pump inhibition by removal of extracellular K+ on membrane potential difference (PD) and [Na+]i. In hepatocyte monolayers, HCO3- increased 22Na+ entry and turnover rates by 50-65%, without measurably altering 22Na+ pool size or cell volume, and HCO3- also increased Na+/K+ pump activity by 70%. In single cells, exposure to HCO3- produced an abrupt and sustained rise in [Na+]i from approximately 8 to 12 mM. Na+/K+ pump activity assessed in single cells by PD excursions during transient K+ removal increased congruent to 2.5-fold in the presence of HCO3-, and the rise in [Na+]i produced by inhibition of the Na+/K+ pump was similarly increased congruent to 2.5-fold in the presence of HCO3-. In intact perfused rat liver, HCO3- increased both Na+/K+ pump activity and O2 consumption. These findings indicate that, in hepatocytes, net coupled Na+ and HCO3- movement is inward and represents a major determinant of Na+ influx and Na+/K+ pump activity. About half of hepatic Na+/K+ pump activity appears dedicated to recycling Na+ entering in conjunction with HCO3- to maintain [Na+]i within the physiologic range

  9. Clues to NaCN formation

    Science.gov (United States)

    Quintana-Lacaci, G.; Cernicharo, J.; Velilla Prieto, L.; Agúndez, M.; Castro-Carrizo, A.; Fonfría, J. P.; Massalkhi, S.; Pardo, J. R.

    2017-11-01

    Context. ALMA is providing us essential information on where certain molecules form. Observing where these molecules emission arises from, the physical conditions of the gas, and how this relates with the presence of other species allows us to understand the formation of many species, and to significantly improve our knowledge of the chemistry that occurs in the space. Aims: We studied the molecular distribution of NaCN around IRC +10216, a molecule detected previously, but whose origin is not clear. High angular resolution maps allow us to model the abundance distribution of this molecule and check suggested formation paths. Methods: We modeled the emission of NaCN assuming local thermal equilibrium (LTE) conditions. These profiles were fitted to azimuthal averaged intensity profiles to obtain an abundance distribution of NaCN. Results: We found that the presence of NaCN seems compatible with the presence of CN, probably as a result of the photodissociation of HCN, in the inner layers of the ejecta of IRC +10216. However, similar as for CH3CN, current photochemical models fail to reproduce this CN reservoir. We also found that the abundance peak of NaCN appears at a radius of 3 × 1015 cm, approximately where the abundance of NaCl, suggested to be the parent species, starts to decay. However, the abundance ratio shows that the NaCl abundance is lower than that obtained for NaCN. We expect that the LTE assumption might result in NaCN abundances higher than the real ones. Updated photochemical models, collisional rates, and reaction rates are essential to determine the possible paths of the NaCN formation. Based on observations carried out with ALMA and the IRAM 30 m Telescope. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. IRAM is supported by INSU/CNRS (France

  10. Quasi–solid state rechargeable Na-CO2 batteries with reduced graphene oxide Na anodes

    Science.gov (United States)

    Hu, Xiaofei; Li, Zifan; Zhao, Yaran; Sun, Jianchao; Zhao, Qing; Wang, Jianbin; Tao, Zhanliang; Chen, Jun

    2017-01-01

    Na-CO2 batteries using earth-abundant Na and greenhouse gas CO2 are promising tools for mobile and stationary energy storage, but they still pose safety risks from leakage of liquid electrolyte and instability of the Na metal anode. These issues result in extremely harsh operating conditions of Na-CO2 batteries and increase the difficulty of scaling up this technology. We report the development of quasi–solid state Na-CO2 batteries with high safety using composite polymer electrolyte (CPE) and reduced graphene oxide (rGO) Na anodes. The CPE of PVDF-HFP [poly(vinylidene fluoride-co-hexafluoropropylene)]–4% SiO2/NaClO4–TEGDME (tetraethylene glycol dimethyl ether) has high ion conductivity (1.0 mS cm−1), robust toughness, a nonflammable matrix, and strong electrolyte-locking ability. In addition, the rGO-Na anode presents fast and nondendritic Na+ plating/stripping (5.7 to 16.5 mA cm−2). The improved kinetics and safety enable the constructed rGO-Na/CPE/CO2 batteries to successfully cycle in wide CO2 partial pressure window (5 to 100%, simulated car exhaust) and especially to run for 400 cycles at 500 mA g−1 with a fixed capacity of 1000 mA·hour g−1 in pure CO2. Furthermore, we scaled up the reversible capacity to 1.1 A·hour in pouch-type batteries (20 × 20 cm, 10 g, 232 Wh kg−1). This study makes quasi–solid state Na-CO2 batteries an attractive prospect. PMID:28164158

  11. Kupokelewa Zaidi Kwa Simu Ya Mkononi Kuliko Kompyuta Na ...

    African Journals Online (AJOL)

    Mtandao wa tovuti ni nyenzo ya msingi katika maendeleo ya uwanja wa mawasiliano unaounganisha watu na jamii mbalimbali katika ulimwengu wa leo unaotandawaa. Katika “ulimwengu wa kwanza na wa pili”, yaani mabara ya Amerika, Uropa na Asia, maendeleo na mapinduzi makubwa katika uwanja wa teknolojia ya ...

  12. Effects of different NaCl Concentrations on germination and ...

    African Journals Online (AJOL)

    Growth was steadily stimulated in both species at lower NaCl levels with best growth stimulation at 50 mM NaCl but was adversely affected by higher NaCl concentration levels (75, 100 and 150 mM). Both species ... Key words: Germination, early seedling growth, NaCl, salinity, Amaranthus hybridus, Celosia argentea.

  13. Ujanibishaji wa Office 2003 na Windows XP kwa Kiswahili Sanifu ...

    African Journals Online (AJOL)

    Mradi wa ujanibishaji wa Office 2003 na Windows XP kwa Kiswahili sanifu ulitekelezwa katika kipindi 2004-2005. Malengo ya mradi yalikuwa: (1) kuandaa istilahi za kompyuta kwa Kiingereza-Kiswahili, na (2) kutafsiri programu nne za kawaida za Office (Outlook, Excel, Word na PowerPoint) na Windows XP. Makala hii ina ...

  14. Mabadiliko Ya Kifonolojia Na Kimofolojia Wakati Wa Utohozi Wa ...

    African Journals Online (AJOL)

    Mwingiliano wa lugha ya Kiswahili na Kiarabu una historia ndefu kidogo. Inasemekana Waarabu walianza muwasala na 'Waswahili' tangu karne ya kwanza (BK) (Polome 1967:9). Kutokana na muwasala huo wa muda mrefu, lugha hizi mbili (Kiarabu na Kiswahili) zimeathiriana sana. Lakini kuna maoni kwamba Kiarabu ...

  15. Utata kuhusu Dhana na Chimbuko la Wahadimu katika Kisiwa cha ...

    African Journals Online (AJOL)

    Data za makala haya zimepatikana kupitia usaili na majadiliano ya majopo ya wazungumzaji wa Kimakunduchi na Unguja na kujadili kwa muhtasari chimbuko la Wahadimu. Kwa muda mrefu dhana ya Wahadimu imekuwa ikijadiliwa kwa mitazamo tofautitofauti kama inavyobainishwa na wataalamu mbalimbali wakiwemo ...

  16. O Passeio Público do Rio de Janeiro na Literatura, na Pintura e na Fotografia do Século XIX

    Directory of Open Access Journals (Sweden)

    Solange de Aragão

    2012-06-01

    Full Text Available Este artigo tem como objetivo geral e mais amplo chamar a atenção dos pesquisadores para a importância da literatura, da pintura e da fotografia como fontes documentais para a construção da História do Paisagismo no Brasil por meio de um estudo de caso muito particular: o Passeio Público do Rio de Janeiro no século XIX. São objetivos específicos apresentar e analisar o modo como esse espaço livre público aparece na literatura, na pintura e na fotografia desse período, considerando suas transformações paisagísticas.

  17. [Reproductive cycle of Lytechinus variegatus (Echinoidea: Toxopneustidae) in the south of Margarita Island, Venezuela].

    Science.gov (United States)

    Montealegre Quijano, Santiago; Gómez Gaspar, Alfredo

    2005-12-01

    The sea urchin Lytechinus variegatus is of some commercial importance on the Southern coast of Margarita Island (Venezuela), where artisan women fishers process and sell the roe. The reproduction cycle of this species had not been fully studied. We collected these sea urchins in two stations from November 1997 through October 1998. The samples were transported fresh to the laboratory to determine weight, diameter and height. The sexual stage was established with a macroscopic scale and the gonadosomatic index (GI). Maturity is achieved when the animals reaches a diameter of 22 mm, although 50% of the population reaches sexual development at diameters of 43 mm (males) and 45 mm (females) at Station 1, and 35 mm for both sexes at Station 2. Mature individuals, in a sexual proportion of 1:1 were collected every month. According to the monthly GI variation and frequency (%) of the development stages, on the southern beaches the main reproductive period begins in April and continues through October, and it is most intensive from May to July, when gonads reach the greatest growth.

  18. On the biosynthesis of 3β-sterols in some representatives of the echinoidea

    NARCIS (Netherlands)

    Voogt, P.A.

    1972-01-01

    1. The incorporation of sodium acetate-1-14C into some classes of lipids inParacentrotus lividus, Echinus acutus andPsammechinus miliaris is investigated. 2. It is demonstrated that these animals utilized the injected acetate for the biosynthesis of fatty acid and non-saponifiable lipids

  19. Hubungan Kepadatan Bulu Babi (Echinoidea dan Tutupan Terumbu Karang pada Kawasan Intertidal Pantai Sanur

    Directory of Open Access Journals (Sweden)

    Tiara Permata Sari

    2017-05-01

    Full Text Available Marine intertidal region is an area that is affected by the mainland. One of the ecosystems found in the intertidal area is the coral reef ecosystem. Urchin is one that lives on these ecosystems. Sanur Beach area has coral reefs and the intertidal zone is quite extensive. The many activities and cruise tourism in Sanur Beach will indirectly affect the life of coral reefs and associated animal in it in this case urchins. The purpose of this study was to determine the relationship density of sea urchins and coral reefs cover percentage in the intertidal area on Sanur Beach. Research done during low tide. Coral reef data collection method and the density of sea urchins using 5x5m quadratic transects were analyzed using Pear Person bivariate correlations. Urchin densities ranging between 0-2.04 ind/m2. The percentage cover coral reefs ranged from 0.1- 17.9%. High and low density of sea urchins and the percentage of coral reefs affected allegedly incompatibility place their lives and because of pressure from community activities in Sanur. The density of sea urchins and the percentage of coral cover has a significant relationship with a strong degree of correlation is 0.79. Positive direction on that relationship means that the higher percentage of coral reefs, the higher density of sea urchins. This assume in which they live almost the same that is in need of a hard substrate and urchins use of coral reefs as a shelter.

  20. SEBARAN BULU BABI (ECHINOIDEA DI KAWASAN PADANG LAMUN PANTAI MERTA SEGARA, SANUR-BALI

    Directory of Open Access Journals (Sweden)

    Timothy Herman Laning

    2015-12-01

    Full Text Available Tujuan penelitian adalah untuk melihat sebaran hewan bulu babi di kawasan padang lamun Pantai Merta Segara, Sanur. Penelitian ini telah dilakukan sebanyak tiga kali ulangan pada saat keadaan surut dari bulanOktober 2012 sampai Februari 2013 di Pantai Merta Segara, Sanur. Penelitian ini menggunakan 4 transek sejajar garis pantai dengan panjang 50 meter, dengan 15 kuadrat berukuran 10x2,5m pada masing-masing transek. Jarak antar transek adalah interval 20 meter. Hasil pengamatan diperoleh 9 spesies (5 famili, yaitu Diadema savignyi, Diadema setosum, Diadema palmeri, Echinothrix calamaris, Echinometra mathei, Echinocardium sp., Mespilia globulus, Tripneustues gratilla dan   Toxopneustes sp.Indeks keragaman yang sedang (H’= 2,43 menunjukanpola penyebaran yang merata (E = 0,76 dan tingkat dominansi yang rendah (D = 0,25. Aktifitas penambatan kapal dan aktivitas wisatawan diduga berdampak netatif terhadap keberadaan lamun yang secara tidak langsung mengancam keberadaan bulu babi. Selain itu, ditemukan adanya keterkaitan antara jumlah spesies bulu babi dengan tipe substrat pasir halus sebagai habitatnya.

  1. Spesies Bulu Babi (Echinoidea) Di Perairan Pulau Panjang Kabupaten Bangka Tengah Provinsi Bangka Belitung

    OpenAIRE

    Rofiza Yolanda, Siti Aisyah Lubis, Arief Anthonius Purnama

    2017-01-01

    This research was carried out in the Island Panjang Central Bangka Tengah province Bangka Belitung from May to July 2016. The aims of this research was to determine the species of sea urchin from Panjang island Central Bangka Tengah District, Bangka Belitung. The method of direct observation consisted of four research stations, namely the length of the island Panjang eastern, Island Panjang northern, Island Panjang westerng and Island Panjang to the south. The results of the research found ...

  2. A Newly Recorded Sea Urchin (Echinoidea: Spatangoida: Spatangidae from Geomundo Island, Korea

    Directory of Open Access Journals (Sweden)

    Sook Shin

    2013-10-01

    Full Text Available A sea urchin was collected from Geomundo Island of Jeollanam-do, Korea on July 3, 2009. This specimen was classified as Spatangus luetkeni A. Agassiz 1872 belonging to the family Spatangidae of order Spatangoida based on the morphological characteristics. This genus and species are newly recorded in Korea. It is distinct morphological characters that test is thick and strong, six to eight primary tubercles are in 1 and 4 interambulacra, sternum is equipped with little keel, and color in alcohol is dark violet. This species inhabits tropical waters and usually distributes over the West Pacific from southern Japan to New Zealand.

  3. A New Record of Sea Urchin (Echinoidea: Stomopneustoida: Glyptocidaridae from the Yellow Sea, Korea

    Directory of Open Access Journals (Sweden)

    Taekjun Lee

    2013-10-01

    Full Text Available Sea urchins were collected from waters adjacent to Daludo Island and Mohang harbor in the Yellow Sea, and were identified into Glyptocidaris crenularis A. Agassiz, 1864, of the family Stomopneustidae within the order Stomopneustoida, based on morphological characteristics. This species has two unique morphological characteristics: the ambulacral plate is composed of three primary plates and two demi-plates, and a valve of globiferous pedicellaria consists of with a well-developed long terminal hook and a unique stalk equipped with one to six long lateral processes covering membranes, resembling fins. It is newly recorded in Korea and is described with photographs. This brings the total number of sea urchins reported from the Yellow Sea, Korea, to seven.

  4. Some fossil Clypeastrids (Echinoidea) from Brimstone Hill (St. Kitts) and Sugar Loaf (St. Eustatius), Lesser Antilles

    NARCIS (Netherlands)

    Engel, H.

    1961-01-01

    In March 1958 Dr. J. H. WESTERMANN and Mr. H. KIEL collected some fossil Echinids on the islands of St. Kitts and St. Eustatius. The fossils of St. Kitts were found in a yellow limestone (sample nr. 42), situated on the west flank of Brimstone Hill, belonging to a series of peculiar-looking upturned

  5. Muziki wa Hip Hop na Haki Za Kijamii: Dhima, Changamoto na ...

    African Journals Online (AJOL)

    Ni dhahiri kuwa haki za kijamii zinaweza kuwasilishwa kwa jamii pana kupitia sanaa ya hip hop. Makala haya basi, yanabainisha dhima na mchango wa muziki wa hip hop katika masuala ya haki za kijamii, yanafafanua changamoto za muziki huu katika kuwasilisha haki za kijamii na kutoa mapendekezo kwa makundi ...

  6. Regeneration of plantlets under NaCl stress from NaN3 treated ...

    African Journals Online (AJOL)

    In this experiment, mutation induction in explants using NaN3 and subsequently, callus growth and plant regeneration under NaCl stressed conditions was assessed in some sugarcane (Saccharum officinarum L.) cultivars (Thatta-10, CPF-237 and SPHS-19). Immature bases of leaf tips were cultured on MS2n (MS salts, 3.0 ...

  7. Molecular dynamics investigation of Na+ in Na2Ni2TeO6

    International Nuclear Information System (INIS)

    Sau, Kartik; Kumar, P. Padma

    2014-01-01

    An inter-atomic potential for Na 2 Ni 2 TeO 6 in the Parrinello- Rahman-Vashishta (PRV) model is parameterized empirically. The potential reproduces variety of structural and transport properties of that material in good agreement with recent experimental results. The study provides fresh insights on the migration channels and mechanism of Na + in the system

  8. NaI(Tl) electron energy resolution

    CERN Document Server

    Mengesha, W

    2002-01-01

    NaI(Tl) electron energy resolution eta sub e was measured using the Modified Compton Coincidence Technique (MCCT). The MCCT allowed detection of nearly monoenergetic internal electrons resulting from the scattering of incident 662 keV gamma rays within a primary NaI(Tl) detector. Scattered gamma rays were detected using a secondary HPGe detector in a coincidence mode. Measurements were carried out for electron energies ranging from 16 to 438 keV, by varying the scattering angle. Measured HPGe coincidence spectra were deconvolved to determine the scattered energy spectra from the NaI(Tl) detector. Subsequently, the NaI(Tl) electron energy spectra were determined by subtracting the energy of scattered spectra from the incident source energy (662 keV). Using chi-squared minimization, iterative deconvolution of the internal electron energy spectra from the measured NaI(Tl) spectra was then used to determine eta sub e at the electron energy of interest. eta sub e values determined using this technique represent va...

  9. Na/K pump inactivation, subsarcolemmal Na measurements, and cytoplasmic ion turnover kinetics contradict restricted Na spaces in murine cardiac myocytes.

    Science.gov (United States)

    Lu, Fang-Min; Hilgemann, Donald W

    2017-07-03

    Decades ago, it was proposed that Na transport in cardiac myocytes is modulated by large changes in cytoplasmic Na concentration within restricted subsarcolemmal spaces. Here, we probe this hypothesis for Na/K pumps by generating constitutive transsarcolemmal Na flux with the Na channel opener veratridine in whole-cell patch-clamp recordings. Using 25 mM Na in the patch pipette, pump currents decay strongly during continuous activation by extracellular K (τ, ∼2 s). In contradiction to depletion hypotheses, the decay becomes stronger when pump currents are decreased by hyperpolarization. Na channel currents are nearly unchanged by pump activity in these conditions, and conversely, continuous Na currents up to 0.5 nA in magnitude have negligible effects on pump currents. These outcomes are even more pronounced using 50 mM Li as a cytoplasmic Na congener. Thus, the Na/K pump current decay reflects mostly an inactivation mechanism that immobilizes Na/K pump charge movements, not cytoplasmic Na depletion. When channel currents are increased beyond 1 nA, models with unrestricted subsarcolemmal diffusion accurately predict current decay (τ ∼15 s) and reversal potential shifts observed for Na, Li, and K currents through Na channels opened by veratridine, as well as for Na, K, Cs, Li, and Cl currents recorded in nystatin-permeabilized myocytes. Ion concentrations in the pipette tip (i.e., access conductance) track without appreciable delay the current changes caused by sarcolemmal ion flux. Importantly, cytoplasmic mixing volumes, calculated from current decay kinetics, increase and decrease as expected with osmolarity changes (τ >30 s). Na/K pump current run-down over 20 min reflects a failure of pumps to recover from inactivation. Simulations reveal that pump inactivation coupled with Na-activated recovery enhances the rapidity and effectivity of Na homeostasis in cardiac myocytes. In conclusion, an autoregulatory mechanism enhances cardiac Na/K pump activity when

  10. Anion-coupled Na efflux mediated by the human red blood cell Na/K pump

    International Nuclear Information System (INIS)

    Dissing, S.; Hoffman, J.F.

    1990-01-01

    The red cell Na/K pump is known to continue to extrude Na when both Na and K are removed from the external medium. Because this ouabain-sensitive flux occurs in the absence of an exchangeable cation, it is referred to as uncoupled Na efflux. This flux is also known to be inhibited by 5 mM Nao but to a lesser extent than that inhibitable by ouabain. Uncoupled Na efflux via the Na/K pump therefore can be divided into a Nao-sensitive and Nao-insensitive component. We used DIDS-treated, SO4-equilibrated human red blood cells suspended in HEPES-buffered (pHo 7.4) MgSO4 or (Tris)2SO4, in which we measured 22Na efflux, 35SO4 efflux, and changes in the membrane potential with the fluorescent dye, diS-C3 (5). A principal finding is that uncoupled Na efflux occurs electroneurally, in contrast to the pump's normal electrogenic operation when exchanging Nai for Ko. This electroneutral uncoupled efflux of Na was found to be balanced by an efflux of cellular anions. (We were unable to detect any ouabain-sensitive uptake of protons, measured in an unbuffered medium at pH 7.4 with a Radiometer pH-STAT.) The Nao-sensitive efflux of Nai was found to be 1.95 +/- 0.10 times the Nao-sensitive efflux of (SO4)i, indicating that the stoichiometry of this cotransport is two Na+ per SO4=, accounting for 60-80% of the electroneutral Na efflux. The remainder portion, that is, the ouabain-sensitive Nao-insensitive component, has been identified as PO4-coupled Na transport and is the subject of a separate paper. That uncoupled Na efflux occurs as a cotransport with anions is supported by the result, obtained with resealed ghosts, that when internal and external SO4 was substituted by the impermeant anion, tartrate i,o, the efflux of Na was inhibited 60-80%. This inhibition could be relieved by the inclusion, before DIDS treatment, of 5 mM Cli,o

  11. Metallic Na formation in NaCl crystals with irradiation of electron or vacuum ultraviolet photon

    Energy Technology Data Exchange (ETDEWEB)

    Owaki, Shigehiro [Osaka Prefecture Univ., Sakai, Osaka (Japan). Coll. of Integrated Arts and Sciences; Koyama, Shigeko; Takahashi, Masao; Kamada, Masao; Suzuki, Ryouichi

    1997-03-01

    Metallic Na was formed in NaCl single crystals with irradiation of a variety of radiation sources and analyzed the physical states with several methods. In the case of irradiation of 21 MeV electron pulses to the crystal blocks, the optical absorption and lifetime measurement of positron annihilation indicated appearance of Na clusters inside. Radiation effects of electron beam of 30 keV to the crystals in vacuum showed the appearance of not only metallic Na but atomic one during irradiation with Auger electron spectroscopy. Intense photon fluxes in vacuum ultraviolet region of synchrotron radiation were used as another source and an analyzing method of ultraviolet photoelectron spectroscopy. The results showed the metallic Na layered so thick that bulk plasmon can exist. (author)

  12. Hydrolysis of Rice Straw Pretreated by Na2SO3 Over Fe-resin/NaCl

    Directory of Open Access Journals (Sweden)

    YANG Hui

    2017-05-01

    Full Text Available To increase the conversion of rice straw(RS and the yield of products, we employed three methods, which were ultrasonic wave, steam explosion and Na2SO3 pretreatment to pretreat RS(the treated RS noted as CS-RS, ZQ-RS and Na2SO3-RS, respectively and found that Na2SO3 treatment was the best pretreatment method based on XRD, SEM, elemental analysis and content of cellulose, hemicellulose and lignin. The conversion of Na2SO3-RS and the yield of total reducing sugar(TRS and levulinic acid(LA were 97.3%, 29.6% and 13.5%, respectively by 10% Fe-resin in 3.3% NaCl solution under 200 ℃.

  13. Muscle K+, Na+, and Cl- disturbances and Na+-K+ pump inactivation: implications for fatigue

    DEFF Research Database (Denmark)

    McKenna, Michael J; Bangsbo, Jens; Renaud, Jean-Marc

    2008-01-01

    (+)-ATPase activity during exercise stabilizes Na(+) and K(+) concentration gradients and membrane excitability and thus protects against fatigue. However, during intense contraction some Na(+)-K(+) pumps are inactivated and together with further ionic disturbances, likely precipitate muscle fatigue.......Membrane excitability is a critical regulatory step in skeletal muscle contraction and is modulated by local ionic concentrations, conductances, ion transporter activities, temperature, and humoral factors. Intense fatiguing contractions induce cellular K(+) efflux and Na(+) and Cl(-) influx......, causing pronounced perturbations in extracellular (interstitial) and intracellular K(+) and Na(+) concentrations. Muscle interstitial K(+) concentration may increase 1- to 2-fold to 11-13 mM and intracellular K(+) concentration fall by 1.3- to 1.7-fold; interstitial Na(+) concentration may decline by 10 m...

  14. Osmotic and ionic effects of NaCl and Na2SO4 salinity on Phragmites australis

    DEFF Research Database (Denmark)

    Pagter, Majken; Bragato, Claudia; Malagoli, Mario

    2009-01-01

    and partly Cl ions from the leaves. Incomplete exclusion of Cl from the leaves may affect aboveground biomass production, which was significantly more reduced by NaCl than Na2SO4. Stomatal conductance was negatively influenced by decreasing water potentials caused by NaCl or Na2SO4, implying that a non...

  15. Structure-function relationships of Na+, K+, ATP, or Mg2+ binding and energy transduction in Na,K-ATPase

    DEFF Research Database (Denmark)

    Jorgensen, Peter L.; Pedersen, Per Amstrup

    2000-01-01

    Na,K-ATPase; Mutagenesis; Na+ binding; K+ binding; Tl+ binding; Mg2+ binding; ATP binding; Cation binding site; Energy transduction......Na,K-ATPase; Mutagenesis; Na+ binding; K+ binding; Tl+ binding; Mg2+ binding; ATP binding; Cation binding site; Energy transduction...

  16. Long-Range Effects of Na(+) Binding in Na,K-ATPase Reported by ATP.

    Science.gov (United States)

    Middleton, David A; Fedosova, Natalya U; Esmann, Mikael

    2015-12-01

    This paper addresses the question of long-range interactions between the intramembranous cation binding sites and the cytoplasmic nucleotide binding site of the ubiquitous ion-transporting Na,K-ATPase using (13)C cross-polarization magic-angle spinning (CP-MAS) solid-state nuclear magnetic resonance. High-affinity ATP binding is induced by the presence of Na(+) as well as of Na-like substances such as Tris(+), and these ions are equally efficient promoters of nucleotide binding. CP-MAS analysis of bound ATP with Na,K-ATPase purified from pig kidney membranes reveals subtle differences in the nucleotide interactions within the nucleotide site depending on whether Na(+) or Tris(+) is used to induce binding. Differences in chemical shifts for ATP atoms C1' and C5' observed in the presence of Na(+) or Tris(+) suggest alterations in the residues surrounding the bound nucleotide, hydrogen bonding, and/or conformation of the ribose ring. This is taken as evidence of a long-distance communication between the Na(+)-filled ion sites in the membrane interior and the nucleotide binding site in the cytoplasmic domain and reflects the first conformational change ultimately leading to phosphorylation of the enzyme. Stopped-flow fluorescence measurements with the nucleotide analogue eosin show that the dissociation rate constant for eosin is larger in Tris(+) than in Na(+), giving kinetic evidence of the difference in structural effects of Na(+) and Tris(+). According to the recent crystal structure of the E1·AlF4(-)·ADP·3Na(+) form, the coupling between the ion binding sites and the nucleotide side is mediated by, among others, the M5 helix.

  17. Eletrencefalograma na síndrome parkinsoniana

    Directory of Open Access Journals (Sweden)

    José Geraldo Camargo Lima

    1973-09-01

    Full Text Available Foram estudados os eletrencefalogramas de 50 pacientes parkinsonianos livres de qualquer antecedente convulsivo, sendo registrados traçados anormais em 40% dos casos. A incidência de traçados anormais foi maior na síndrome parkinsoniana bilateral do que na unilateral (52% e 25%, respectivamente. Entre as anormalidades assinaladas foram as paroxísticas as mais freqüentes (65% dos casos, caracterizando-se predominantemente por surtos de ondas teta. O registro de anormalidades paroxísticas do tipo irritativo encontrado em três casos é salientado. Alterações da atividade de base foram assinaladas em 35% dos pacientes. A idade dos pacientes não parece ter tido importante papel na gênese das anormalidades eletrencefalográficas.

  18. Knjige o kartografskim projekcijama na internetu

    Directory of Open Access Journals (Sweden)

    Nedjeljko Frančula

    2011-12-01

    Full Text Available U ovom prikazu skrećemo pozornost na neke knjige o kartografskim projekcijama koje su prvobitno objavljene u tisku, a potom digitalizirane i besplatno stavljene na mrežu. Neke od tih knjiga nude se na mreži kao Google e-knjige. Google godinama skuplja knjige kojima su istekla autorska prava i digitalizira ih. Fotografira se svaka stranica te zatim spaja u jednu veliku fotografiju iz koje se izvlači tekst softverom OCR. Google čuva originalnu digitalnu fotografiju u svom arhivu, a izvučeni tekst pretvara u formate HTML, PDF ili EPUB. Google danas nudi više od milijun besplatnih e-knjiga (http://www.google.com/books.

  19. Tecnologia simplificada na enfermagem materno infantil

    Directory of Open Access Journals (Sweden)

    Selma Campestrini

    1991-09-01

    Full Text Available A autora apresenta três modelos de tecnologia simplificada da enfermagem materno infantil: o equipamento didático SEIO COBAIA para treinar exercícios e massagens da mama e mamilo; a peça indumentária SUPRETRAUMA - sutiã preventivo de traumatismo mamilar - usado por gestantes; e, a técnica para reverter mamilo umbilicado durante o puerperio imediato. Além de corroborar na promoção do aleitamento materno e na prevenção de desmame precoce, demonstra a possibilidade da enfermagem relacionar o saber teórico-científico com o saber tecnico-prático, na saúde da mulher e da criança, com tecnologia adequada às necessidades, à compreensão e ao bem estar da população.

  20. Hidroginástica na terceira idade

    OpenAIRE

    Paula, Karla Campos de; Paula, Débora Campos de

    1998-01-01

    O processo de envelhecimento no indivíduo saudável está relacionado com inúmeras alterações psicológicas e físicas que interferem na área motora, concorrendo para a inatividade e contribuindo para o aparecimento e agravamento de determinadas doenças, além de influenciar negativamente a realização das atividades de vida diária. Portanto, a prática de atividade física é fundamental para o idoso, não só na prevenção de doenças como na reabilitação de suas habilidades motoras, promovendo um estil...

  1. Labirintos na cidade contemporânea

    Directory of Open Access Journals (Sweden)

    Edson Luiz André de Sousa

    Full Text Available Este artigo pretende tensionar pontos de conexão e diluição de fronteiras entre as categorias público/privado, conversando com a literatura de Baudelaire e W. Benjamin, Fredric Jamenson e Marc Augé. Através da imagem do labirinto, símbolo da cidade antiga que se quis extinguir na cidade moderna, busca-se refletir sobre alguns caminhos e caminhantes considerados excedentes na cidade contemporânea. O cenário propulsor dessa reflexão é a experiência do jornal Boca de Rua, elaborado por moradores de rua na cidade de Porto Alegre.

  2. Crystal structure of a Na+-bound Na+,K+-ATPase preceding the E1P state.

    Science.gov (United States)

    Kanai, Ryuta; Ogawa, Haruo; Vilsen, Bente; Cornelius, Flemming; Toyoshima, Chikashi

    2013-10-10

    Na(+),K(+)-ATPase pumps three Na(+) ions out of cells in exchange for two K(+) taken up from the extracellular medium per ATP molecule hydrolysed, thereby establishing Na(+) and K(+) gradients across the membrane in all animal cells. These ion gradients are used in many fundamental processes, notably excitation of nerve cells. Here we describe 2.8 Å-resolution crystal structures of this ATPase from pig kidney with bound Na(+), ADP and aluminium fluoride, a stable phosphate analogue, with and without oligomycin that promotes Na(+) occlusion. These crystal structures represent a transition state preceding the phosphorylated intermediate (E1P) in which three Na(+) ions are occluded. Details of the Na(+)-binding sites show how this ATPase functions as a Na(+)-specific pump, rejecting K(+) and Ca(2+), even though its affinity for Na(+) is low (millimolar dissociation constant). A mechanism for sequential, cooperative Na(+) binding can now be formulated in atomic detail.

  3. A perda de chance na responsabilidade civil

    OpenAIRE

    Silva, Rute Eunice Andrade Teixeira da

    2017-01-01

    Resumo: O presente trabalho tem como objecto de estudo a teoria da perda de chance. Tema ainda controverso tanto na doutrina como na jurisprudência, urge fazer-se uma análise do mesmo no âmbito do direito português. Para um melhor entendimento sobre a figura da perda de chance, é necessário ter presente alguns aspectos do instituto da responsabilidade civil. Será realizada uma análise geral dos pressupostos da responsabilidade civil, versando-nos principalmente sobre o dano e o ne...

  4. O trabalho na África subsariana

    OpenAIRE

    Carneiro, Emmanuel Moreira

    2008-01-01

    A natureza do trabalho e do mercado de emprego na África subsariana está intrinsecamente ligado ao tipo de produção material dominante, à natureza das relações de produção estabelecidas, bem como ao inerente sistema de formação e distribuição do rendimento. É ainda profundamente condicionada pela evolução do processo de estruturação mundial do capitalismo, o qual se traduz, na fase actual, pelo que se convencionou designar mundialização e globalização.

  5. A TEOLOGIA LATINO-AMERICANA NA ENCRUZILHADA

    Directory of Open Access Journals (Sweden)

    Victor Codina

    1999-01-01

    Full Text Available As mudanças ocorridas no mundo, no fim dos anos 80, não podem deixar de afetar a Teologia latino-americana e, muito concretamente, a Teologia da Libertação (TdL, teologia que nasceu na América Latina na década de 701. A TdL encontra-se hoje numa encruzilhada: retroceder e dar marcha a ré? Continuar repetindo o que até agora foi dito, como se nada tivesse acontecido?

  6. A Imagem como Ruína

    Directory of Open Access Journals (Sweden)

    Míriam Volpe

    2001-12-01

    Full Text Available O dialogismo ente o filme Citizen Kane, de Orson Welles, e o poema “Kubla Khan”, de S.T. Coleridgé, é analisado, sendo evidenciados não só o tema em comum – o mito do Paraíso perdido – como também a similariedade na organização do disurso na justaposição das images, como fragmentos da memória a serem preservados.

  7. Sexualidade na velhice e qualidade de vida

    OpenAIRE

    Viana, Helena Brandão; Madruga, Vera Aparecida

    2010-01-01

    O objetivo deste trabalho, realizado por meio de uma revisão de literatura, foi abordar uma revisão literária sobre a influência da sexualidade na qualidade de vida deidosos, temática pouco discutida nas diferentes áreas de pesquisas sobre envelhecimento. Diante da escassez de bibliografia na cultura brasileira, apresentou-se uma revisão de literatura sobre envelhecimento junto à temática da sexualidade, trazendo uma trajetória histórica sobre estudos de sexualidade ao longo do tempo, discuti...

  8. E-GRADIVA NA PRIMERU OBRAVNAVE GLAGOLA

    OpenAIRE

    Kajtna, Tjaša

    2013-01-01

    Sodobne tehnologije so korenito spremenile današnji način življenja. Tako je tudi z izobraževanjem. Vedno več učiteljev ob klasičnih metodah poučevanja uporablja tudi nove pristope, ki so povezani s sodobnimi tehnologijami. V diplomskem delu je opredeljeno e-izobraževanje, predstavljene so nove tehnologije, ki se pojavljajo v povezavi z le-tem. V nadaljevanju sledi teoretična obravnava e-gradiv, ki ob podpori informacijsko komunikacijskih tehnologij predstavljajo temelj e-izobraževanja. ...

  9. ANALIZA IZGUB NA OSLABLJENEM PRENAPETOSTNEM ODVODNIKU

    OpenAIRE

    Ajdnik, Miran

    2011-01-01

    Diplomska naloga obravnava problematiko izgub električne energije na oslabljenem prenapetostnem odvodniku na transformatorski postaji Kot-Makej (0,95/0,4 kV) in neozemljenem izvoru. Omenjena transformatorska postaja se napaja iz razdelilne transformatorske postaje Ravne (RTP RAVNE) preko 20 kV daljnovoda Mežica in transformatorske postaje Kot (20/0,95/0,4 kV). Rešitev je predstavljena s programskim orodjem MATLAB/Simulink iz knjižnice PowerSystem, s katerim je izvedena simulacija pri oslablje...

  10. Vpliv tripsinizacije na celice Caco-2.

    OpenAIRE

    Cuculić, Nika

    2018-01-01

    Caco-2 celična linija se uporablja v številnih predkliničnih raziskavah. Ena izmed najbolj izraženih lastnosti celične linije Caco-2 je njihova zmožnost spontane diferenciacije. Zaradi različnega rokovanja s celično linijo Caco-2 med laboratoriji, v kar spada tudi uporaba različnih koncentracij tripsina ter čas izpostavljenosti celic tripsinu, se rezultati raziskav med laboratoriji lahko zelo razlikujejo in niso primerljivi. Preverili smo vpliv različnih koncentracij tripsina na celično viabi...

  11. Izbor i prilagodba nadogradnje na implantatima

    OpenAIRE

    Belamarić, Sara

    2017-01-01

    Implantatne nadogradnje su spojni elementi između tijela implantata, kirurški postavljenog u kost, koji predstavlja zamjenu za prirodni korijen zuba i protetske suprastrukture kojom se nadoknađuje oblik, boja i funkcija zuba koji nedostaje. One predstavljaju središte funkcijskih i estetskih aspekata implantološke terapije. Imaju direktan utjecaj na dugoročnu prognozu i uspjeh ovog terapijskog postupka. Danas na tržištu postoji čitav niz dostupnih implantatnih nadogradnji. Najčešći materijali ...

  12. Recent results and prospects from NA62

    Directory of Open Access Journals (Sweden)

    Bizzeti Andrea

    2016-01-01

    K+ → π+ vv̄ is a theoretically very clean decay where indirect effects of new physics may be detectable. The NA62 apparatus has been significantly upgraded between 2008 and 2014 in order to measure the branching ratio of this decay with 10% precision. The NA62 experiment took data with the new setup in pilot runs in 2014 and 2015, reaching the design beam intensity. Results of first data quality studies in view of the 2016-2017 physics runs are presented.

  13. MEDGENERACIJSKI PRENOS ZNANJA NA DELOVNEM MESTU

    OpenAIRE

    Movern, Tina

    2015-01-01

    Prenos znanja med ljudmi igra ključno vlogo pri razvoju ter napredku človeštva. Nekaterih najbolj kompleksnih znanj kot so jeziki in kulturne norme, so lahko naučena oziroma priučena od drugih ljudi, ti pa so jih pridobili od prejšnjih generacij. Kot glavno gonilno silo razvoja neke organizacije bi prav lahko vzeli količino, kvaliteto in možnost upravljanja prenosa znanj v sami organizaciji, kar je tudi glavni predmet naše raziskave. Diplomska naloga je razdeljena na teoretični in empiri...

  14. Osteossarcoma parosteal: aspectos na radiologia convencional

    OpenAIRE

    Nanci Neto,Francisco; Marchiori,Edson; Vianna,Alberto Domingues; Aymoré,Ierecê Lins; Almeida,Ana Luiza Brito de; Irion,Klaus L.; Collares,Felipe Birchal

    2007-01-01

    OBJETIVO: Avaliar os achados clínicos mais importantes do osteossarcoma parosteal e descrever os seus aspectos mais comuns na radiologia convencional. MATERIAIS E MÉTODOS: Estudo retrospectivo com 26 pacientes com osteossarcoma parosteal, provenientes do arquivo do Clube do Osso, Rio de Janeiro, RJ, e análise dos principais achados clínicos e aspectos radiológicos. RESULTADOS: A doença predominou em pacientes do sexo feminino e teve idade média de acometimento na terceira década de vida. Os a...

  15. O problema do conhecimento verdadeiro na epidemiologia

    Directory of Open Access Journals (Sweden)

    Ayres José Ricardo de Carvalho Mesquita

    1992-01-01

    Full Text Available São examinadas as bases filosóficas da validação do conhecimento científico, com o intuito de estabelecer uma visão crítica a respeito da adoção das proposições de Popper na epidemiologia. Ressalta-se o caráter conservador que resulta das limitações técnicas implicadas na sua adoção, não obstante o evidente aumento da racionalidade e da criatividade heurística que propicia.

  16. Na+/K+-ATPase: Activity and inhibition

    Science.gov (United States)

    Čolović, M.; Krstić, D.; Krinulović, K.; Momić, T.; Savić, J.; Vujačić, A.; Vasić, V.

    2009-09-01

    The aim of the study was to give an overview of the mechanism of inhibition of Na+/K+-ATPase activity induced by some specific and non specific inhibitors. For this purpose, the effects of some ouabain like compounds (digoxin, gitoxin), noble metals complexes ([PtCl2DMSO2], [AuCl4]-, [PdCl4]2-, [PdCl(dien)]+, [PdCl(Me4dien)]+), transition metal ions (Cu2+, Zn2+, Fe2+, Co2+), and heavy metal ions (Hg2+, Pb2+, Cd2+) on the activity of Na+/K+-ATPase from rat synaptic plasma membranes (SPM), porcine cerebral cortex and human erythrocytes were discussed.

  17. Na, K-ATPase as signaling transducer

    OpenAIRE

    Li, Juan

    2007-01-01

    It is now generally agreed that Na,K-ATPase (NKA), in addition to its role in the maintenance of Na+ and K+ gradients across the cell membrane, is a signal transducer. Our group has identified a novel signaling pathway where NKA interact with IP3R to form a signaling microdomain. Ouabain, a specific ligand of NKA, activates this pathway, triggers slow Ca2+ oscillations and activates NF-κB. In current study, the molecular mechanisms and some important downstream effects of NK...

  18. Europlanet-2020 NA1 Exchange Program

    Science.gov (United States)

    Genzer, M.; Szego, K.; Haukka, H.; Harri, A.-M.

    2017-09-01

    The task of Exchange Program of NA1 is to support the activities of EPN2020 with experts and scientific exchange whenever it is needed. Short visits (up to 1 week) with the goal of improving infrastructure facilities and services offered to the scientific community are supported from this task. Since the start of the EPN2020 in September 2015 we have received and approved 14 applications for exchange program travel. More general and specifically targeted calls are planned for the future. The calls are announced on Europlanet-2020 NA1 web site.

  19. Abordagem neurologica na sindrome do X fragil

    OpenAIRE

    Marilisa Mantovani Guerreiro

    1993-01-01

    Resumo: Com o propósito de realizar a abordagem neurológica na Síndrome do X Frágil (SXF), estudaram-se 11 pacientes com este diagnóstico citogenético. A idade variou de 8 a 19 anos. Nove pacientes eram do sexo masculino e dois do feminino. Todos os indivíduos apresentaram pavilhões auriculares grandes e faces alongadas. Observou-se fronte proeminente em 63% dos casos e macrorquidia em 33% dentre aqueles do sexo masculino. Atraso na aquisição da fala, fala repetitiva, perseverativa, impulsiva...

  20. MANAGEMENT DOGODKOV NA PRIMERU NIKE KONVENCIJE

    OpenAIRE

    Kapić, Sara

    2010-01-01

    V diplomski nalogi je predstavljen potek ustvarjanja in izvedbe dogodka, ki zajema številne aktivnosti, in sicer na primeru Nike konvencije. Namen diplomske naloge je namreč podati kritično oceno izvajanja aktivnosti, z namenom ugotoviti, katere aktivnosti bi se v okviru upravljanja z dogodkom lahko izpeljale boljše in podati predloge za uspešnejšo zasnovo in organizacijo naslednje Nike konvencije. Na podlagi posnetka je ugotovljeno, da je pri organizaciji, vodenju, izvedbi in nadzoru prihaja...

  1. Alterações cognitivas na esquizofrenia

    OpenAIRE

    THEIL, Ruth Bonow

    2003-01-01

    Este estudo é uma revisão da literatura sobre o comprometimento cognitivo na esquizofrenia. Objetivou-se a análise da natureza e do padrão desse comprometimento, o estabelecimento de associações entre as variáveis clínicas e o desempenho neuropsicológico, e a determinação das correlações entre os déficits cognitivos na esquizofrenia e seus substratos neurais subjacentes. Foram inicialmente revistos os conceitos de esquizofrenia e sua evolução histórica, aspectos clínicos, cl...

  2. IDENTIDADE E CORPO NA MARCHA DAS VADIAS

    OpenAIRE

    Ribeiro Quintanilha de Souza, Aline

    2015-01-01

    O objetivo deste trabalho é analisar os temas de identidade de gênero e corporalidade na Marcha das Vadias. Esta é um movimento social que tem recebido visibilidade e experimentado um grande crescimento em adeptos e importância para as questões de gênero no Brasil. Este trabalho busca entender como práticas corporais são construídas para um objetivo político específico. Pretendo relacionar as principais reivindicações políticas desenvolvidas na manifestação com a construção da identidade "vad...

  3. Glutathionylation-Dependence of Na(+)-K(+)-Pump Currents Can Mimic Reduced Subsarcolemmal Na(+) Diffusion.

    Science.gov (United States)

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J; Rasmussen, Helge H

    2016-03-08

    The existence of a subsarcolemmal space with restricted diffusion for Na(+) in cardiac myocytes has been inferred from a transient peak electrogenic Na(+)-K(+) pump current beyond steady state on reexposure of myocytes to K(+) after a period of exposure to K(+)-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na(+) that accumulated in the diffusion-restricted space during pump inhibition in K(+)-free extracellular solution. However, there are no known physical barriers that account for such restricted Na(+) diffusion, and we examined if changes of activity of the Na(+)-K(+) pump itself cause the transient peak current. Reexposure to K(+) reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na(+) concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K(+)-free pipette solution could not be reconciled with restricted subsarcolemmal Na(+) diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na(+)- and K(+) concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na(+)-K(+) pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na(+)-K(+) pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K(+)-induced peak Na(+)-K(+) pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K(+)-induced peak Na(+)-K(+) pump current reflects the effect

  4. In vivo PTH provokes apical NHE3 and NaPi2 redistribution and Na-K-ATPase inhibition

    DEFF Research Database (Denmark)

    Zhang, Y; Norian, J M; Magyar, C E

    1999-01-01

    The aim of this study was to test the hypothesis that in vivo administration of parathyroid hormone (PTH) provokes diuresis/natriuresis through redistribution of proximal tubule apical sodium cotransporters (NHE3 and NaPi2) to internal stores and inhibition of basolateral Na-K-ATPase activity....../diuresis and NHE3 and NaPi2 internalization, and that Na-K-ATPase inhibition is not secondary to depressed apical Na+ transport....

  5. The holothurian (Echinodermata) diversity of the Glorieuses Islands ...

    African Journals Online (AJOL)

    Temporal comparisons at local and regional scales using the same methodology show that the diversity in Glorieuses is high and suggests that the biodiversity is increasing as we go from South to North in the Mozambique channel, as observed also for other taxa associated with coral reefs (fish and hard corals).

  6. Peptidoglycan recognition proteins with amidase activity in early deuterostomes (Echinodermata).

    Science.gov (United States)

    Coteur, Geoffroy; Mellroth, Peter; De Lefortery, Coline; Gillan, David; Dubois, Philippe; Communi, David; Steiner, Håkan

    2007-01-01

    Despite the ecological and evolutionary importance of echinoderms, very little is known about the immune mechanisms in this group especially regarding humoral immunity. In this paper, we screened for proteins putatively involved in immunity in the common European seastar Asterias rubens using a mass spectrometry-based proteomic approach. Two proteins showed striking sequence similarities with peptidoglycan recognition proteins (PGRPs). The two seastar proteins were identified as a single protein, termed PGRP-S1a, occurring in two forms in the coelomic plasma, one of 20kDa and another of 22kDa. We also cloned and sequenced a second member of the PGRP family, termed PGRP-S2a. It has a calculated molecular mass of 21.3kDa and is expressed in circulating phagocytes. Both the S1a-cDNA from coelomic epithelium RNA and the S2a-cDNA from phagocytes code for the amino acid residues necessary for peptidoglycan degradation. PGRP-S1a did not affect the phagocytic activity of seastar immune cells towards Micrococcus luteus but inhibited their production of reactive oxygen species (ROS). A recombinant, His-tagged, PGRP-S2a degrades peptidoglycan and increases the phagocytosis of M. luteus cells by seastar phagocytes.

  7. Innate immune response in the sea urchin Echinometra lucunter (Echinodermata).

    Science.gov (United States)

    de Faria, Marcos Tucunduva; da Silva, José Roberto Machado Cunha

    2008-05-01

    Echinometra lucunter, (Pindá) is a sea urchin encountered in the Brazilian coast and exposed to high and low temperatures related to low and high tides. Despite their great distribution and importance, few studies have been done on the biological function of their coelomocytes. Thus, Echinometra lucunter perivisceral coelomocytes were characterized under optical and transmission electron microscopy. Phagocytic amoebocytes in the perivisceral coelom were labelled by injecting ferritin, and ferritin labelled phagocytic amoebocytes were found in the peristomial connective tissue after injecting India ink into the tissue, indicating the amoebocytes ability to respond to an inflammatory stimulus. Results showed that the phagocytic amoebocytes were the main inflammatory cells found in the innate immune response of E. lucunter. While other works have recorded these phenomena in sea urchins found in moderate and constant temperature, this study reports on these same phenomena in a tropical sea urchin under great variation of temperature, thus providing new data to inflammatory studies in invertebrate pathology.

  8. Phylogeography of Holothuria (Halodeima inornata Semper, 1868 (Echinodermata: Holothuroidea

    Directory of Open Access Journals (Sweden)

    Elba Prieto-Rios

    2014-10-01

    Full Text Available Genetic structure of the populations of H. inornata was evaluated and the barriers for genetic flux and historic processes were investigated. Samples were collected trying to cover the distribution range of the species, from Mexico to northern Perú. Based on COI sequences, 118 haplotypes from 220 specimens were detected; the differences between such haplotypes were due to 97 variable sites (21.41% of the 453 bp sequenced. A high haplotype diversity (h=0.979 and a moderate nucleotidic diversity were observed. The values of Fst, the exact test of population differentiation, and the molecular variance analysis (AMOVA were used in order to analyze the genetic differentiation. These analyses suggest the existence of two populations: northern, off the coasts of Sinaloa, Jalisco, Michoacán, Guerrero, and Oaxaca, and southern, off the coasts of Chiapas, El Salvador, Panamá and Perú. Historic events and oceanographic patterns may be the main factors determining dispersion and structure of Hi populations. It seems probable that the original population have extended first in the south and then northern. Besides, the split between these two populations may be due to several tectonic and oceanographic events constituting a barrier for H. inornata settling.

  9. NEW TRIASSIC ASTEROIDEA (ECHINODERMATA SPECIMENS AND THEIR EVOLUTIONARY SIGNIFICANCE

    Directory of Open Access Journals (Sweden)

    DANIEL B. BLAKE

    2017-04-01

    Full Text Available The Paleozoic-Mesozoic transition saw the disappearance of asteroid stem groups and the ascent of the crown group, but late Paleozoic and Triassic asteroids are rare and transition events are poorly documented. Three new Middle and Late Triassic specimens augment existing data; included are a specimen of Trichasteropsis weissmanni from Germany, a specimen of Trichasteropsis? sp. indet. from Italy, and a possible member of the extant Poraniidae from Slovenia. Presence of a small ossicle at the interbrachial midline and adjacent to the marginal series of the new T. weissmanni specimen is consistent with similar expressions not only of other trichasteropsids but also occurrence of two interbrachial ossicles in Paleozoic, stem-group asterozoans; presence is in turn consistent with a hypothesis of derivation of the axillary/odontophore coupling from two ossicles rather than direct derivation of the crown-group odontophore from a single stem-group axillary. Morphology of Trichasteropsis? sp. indet., including, for example, the evenly-tapering arms are reminiscent of those of diverse crown-group asteroids whereas the enlarged distal arms of T. weissmanni are unique, the morphology of T? sp. indet. thereby potentially indicative of a plesiomorphic, stemward positioning within the Trichasteropsiidae. The range of the Poraniidae is tentatively extended to the Carnian. Similarities shared by the Poraniidae and the Trichasteropsiidae suggest stemward positioning within crown-group diversification; however, known Triassic fossils do not appear closely related to extant taxa identified in recent molecular studies as basal within the crown-group. A temperate climate is suggested as preferred by the Triassic asteroids rather than a tropical, warmer one.

  10. Biological results of the Snellius expedition : XXIX. Echinodermata, Asteroidea

    NARCIS (Netherlands)

    Jangoux, M.

    1978-01-01

    Twenty-eight species of starfish were collected during the Snellius Expedition (19291930). The collection contains seven rare or uncommon species, i.e., Astropecten novaeguineae, A. sumbawanus, Celerina heffernani, Fromia eusticha, Disasterina abnormalis, Nepanthia briareus and Echinaster

  11. [Echinoderms (Echinodermata) from the Gulf of California, Mexico].

    Science.gov (United States)

    Solís-Marín, Francisco A; Laguarda-Figueras, Alfredo; Durán-González, Alicia; Ahearn, Cynthia Gust; Torres Vega, Juan

    2005-12-01

    A systematic list of the echinoderms of the Gulf of California, based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnologia, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. A total of 193 echinoderm species is recorded, distributed in 108 genera, 51 families and 19 orders. 12 new records for the Gulf of California are presented: Asteroidea (four), Ophiuroidea (three) and Holothuroidea (five).

  12. Aspidochirotida (Echinodermata: Holothuroidea) from the northeast coast of Brazil.

    Science.gov (United States)

    Prata, Jéssica; Manso, Cynthia L C; Christoffersen, Martin L

    2014-11-28

    This is a taxonomic work on the aspidochirotid sea cucumbers from shallow waters in Northeast Brazil. We studied 165 specimens, classified into 2 families, 3 genera, 7 subgenera and 9 species. Descriptions, illustrations and literature data are included for each species, in addition to ecological notes and information on their distribution in the northeast coast of Brazil. A taxonomic key is provided for the identification of the species.

  13. Revision of some ophiuroid records (Echinodermata: Ophiuroidea) from Argentina.

    Science.gov (United States)

    Brogger, Martin I; O'Hara, Timothy D

    2015-06-12

    The taxonomy of some ophiuroids reported from off Argentina, western Antarctica and the SW Atlantic Ocean is reviewed. The species Amphilepis sanmatiensis, known only from the small holotype, is a synonym of Amphioplus lucyae. This synonymy removes the only reported endemic ophiuroid from Argentina. The species name "Ophiacantha ingrata Koehler, 1923" used for specimens from South Georgia is invalid; the specimens are likely to belong to one of two cryptic species within the O. vivipara complex. Specimens of Amphiura joubini reported from Argentina are re-identified as Amphiura princeps, and specimens of Ophiactis amator from the Antarctic Peninsula are re-identified as Ophiactis asperula.

  14. Asterinid seastars from the Mozambique Channel (Echinodermata: Asteroidea: Asterinidae).

    Science.gov (United States)

    O'Loughlin, P Mark; Mackenzie, Melanie

    2013-02-08

    A new fissiparous asterinid seastar Aquilonastra chantalae sp. nov. is described from Europa Island, one of the Scattered Islands (Les îles Éparses) in the Mozambique Channel. It is compared with the fissiparous asterinid Aquilonastra conandae O'Loughlin & Rowe from the Mascarene Islands. A table of distinguishing diagnostic characters is provided. The asterinid Aquilonastra richmondi O'Loughlin & Rowe is reported for Europa Island.

  15. Melatonin production in the sea star Echinaster brasiliensis (Echinodermata).

    Science.gov (United States)

    Peres, Rafael; Amaral, Fernanda Gaspardo; Marques, Antonio Carlos; Neto, José Cipolla

    2014-04-01

    The primary hormone of the vertebrate pineal gland, melatonin, has been identified broadly throughout the tree of life, in animals, plants, and fungi, supporting a deep evolutionary origin for this signaling molecule. However, some key groups have not been studied. Echinoderms, deuterostome animals, are one of these groups. Herein we study the presence of melatonin and enzymes of its pathway in the sea star Echinaster brasiliensis. We demonstrate that E. brasiliensis produces endogenous melatonin, in the gonads, under a circadian pattern with a nocturnal peak of production. We also show that the enzymes arylalkylamine N-acetyltransferase (AANAT) and tryptophan hydroxylase (TPH) are present and are probably regulating the melatonin production.

  16. Ophiuroidea (Echinodermata) from coral reefs in the Mexican Pacific

    Science.gov (United States)

    Granja–Fernández, Rebeca; Herrero-Pérezrul, María D.; López-Pérez, Ramón A.; Hernández, Luis; Rodríguez-Zaragoza, Fabián A.; Jones, Robert Wallace; Pineda-López, Rubén

    2014-01-01

    Abstract There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix) spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened. PMID:24843284

  17. Status and applications of echinoid (phylum echinodermata) toxicity test methods

    Energy Technology Data Exchange (ETDEWEB)

    Bay, S.; Burgess, R.; Nacci, D.

    1993-01-01

    The use of echinoderms for toxicity testing has focused primarily on sea urchins and sand dollars (Strongylocentrotus purpuratus, Arbacia punctulata, Lytechinus pictus, and Dendraster excentricus, for example). The status and relative sensitivity of various test methods are described. The most frequently used test methods consist of short-term exposures of sea urchin sperm or embryos; these tests can be easily conducted at all times of the year by using species with complementary spawning cycles or laboratory conditioned populations of a single species. Data from reference toxicant and effluent toxicity tests are summarized. Information on the precision and sensitivity of echinoid test methods are limited and preclude rigorous comparisons with other test methods. The available data indicate that the sensitivity and precision of these methods are comparable to short-term chronic methods for other marine invertebrates and fish. Recent application of the sperm test in toxicity identification evaluations (TIEs) and studies of effluent toxicity decay and sediment toxicity illustrate the versatility of this rapid (10 to 60 min exposure) test method. Embryo tests typically use a 48 to 96 h exposure period and measure the occurrence of embryo malformations. Most recent applications of the embryo test have been for the assessment of sediment elutriate toxicity. Adult echinoderms are not frequently used to assess effluent or receiving water toxicity. Recent studies have had success in using the adult life stage of urchins and sand dollars to assess the effects of contaminated sediment on growth, behavior, and bioaccumulation.

  18. Ophiuroidea (Echinodermata from coral reefs in the Mexican Pacific

    Directory of Open Access Journals (Sweden)

    Rebeca Granja Fernández

    2014-05-01

    Full Text Available There are numerous and important coral reefs in the Mexican Pacific, but scarce studies of brittle stars conducted in these ecosystems. In this regard, this work provides the first annotated checklist of brittle stars associated with coral communities and reefs in the Mexican Pacific and an illustrated key to identify the species. We also provide taxonomic descriptions, spatial and bathymetric distributions and some important remarks of the species. We report a total of 14 species of brittle stars belonging to nine genera and seven families. Ophiocnida hispida in Jalisco, Ophiophragmus papillatus in Guerrero, and Ophiothrix (Ophiothrix spiculata and Ophiactis simplex in Colima are new distribution records. The record of O. papillatus is remarkable because the species has not been reported since its description in 1940. The brittle stars collected in this study, represent 22.2% of the total species previously reported from the Mexican Pacific. Presently, anthropogenic activities on the coral reefs of the Mexican Pacific have increased, thus the biodiversity of brittle stars in these ecosystems may be threatened.

  19. Species diversity in the cryptic abyssal holothurian Psychropotes longicauda (Echinodermata)

    Science.gov (United States)

    Gubili, Chrysoula; Ross, Elizabeth; Billett, David S. M.; Yool, Andrew; Tsairidis, Charalampos; Ruhl, Henry A.; Rogacheva, Antonina; Masson, Doug; Tyler, Paul A.; Hauton, Chris

    2017-03-01

    Despite the plethora of studies on swallow-water invertebrates, almost nothing is known about the evolution and population structure of deep-sea species at the global scale. The aim of this study was to assess phylogeographic patterns of a common and cosmopolitan, predominantly abyssal sea cucumber, Psychropotes longicauda, based on samples from the Atlantic, Southern, Indian and Pacific oceans. Sequences of the mitochondrial COI and 16S genes were analysed for 128 specimens of P. longicauda. In addition, temporal genetic variation was investigated at one site, the Porcupine Abyssal Plain, NE Atlantic Ocean over a period of 34 years. Two distinct lineages within the global distribution were identified. The sister clades probably could be classified as separate species based on the observed genetic divergence (>5.0%) and phylogenetic reconstruction with indications of a Southern Hemisphere origin. Moreover, significant population differentiation was detected between the North Atlantic and localities in both the Pacific and Indian oceans. No bathymetric structuring was detected among lineages. Temporal genetic shifts were detected in a time series of samples from 1977 to 2011. Our data confirm the previously suspected cryptic species diversity throughout the wide distributional range previously attributed to the single species P. longicauda. The presence of sympatric species in the North Pacific and Indian Oceans has been underestimated by previous morphological analyses. The differentiation at the population level detected in the main lineages among the four oceans could suggest restricted gene flow despite wide-scale dispersal potential of the species.

  20. A revision of the genus Atelecrinus PH Carpenter (Echinodermata: Crinoidea).

    Science.gov (United States)

    Messing, Charles G

    2013-01-01

    The unusual bathyal comatulid crinoid genus Atelecrinus is widespread in the Atlantic and tropical Pacific Oceans and currently includes three recognized species. A re-assessment based on examination of new and existing specimens requires establishment of two new genera and five new species, and returns three junior synonyms to species-level status. Paratelecrinus is erected to accommodate Atelecrinus wyvilli PH Carpenter, A. conifer AH Clark, A. cubensis PH Carpenter, P. orthotriremis, new species, P. amenouzume new species, P. laticonulus new species and P. telo new species. Adelatelecrinus is erected to accommodate Atelecrinus sulcatus AH Clark and Adelatelecrinus vallatus new species. Atelecrinus retains A. balanoides PH Carpenter and A. helgae AH Clark, which restricts the genus to the Atlantic. In both Paratelecrinus and Adelatelecrinus, the basals articulate with the centrodorsal via ligament bundles anchored in deep ringlike interradial pits that project into the centrodorsal cavity, whereas in Atelecrinus the centrodorsal rim has shallow interradial concavities and attaches to the basals via a tight junction with no obvious ligament bundles. The spoon-shaped aboral fossa in the basals of Paratelecrinus appears to be unique among articulate crinoids and differs from the smooth fossa found in both Atelecrinus and Adelatelecrinus. New material extends the range of the family to the Indian Ocean. A few species are now known from enough specimens to identify some ontogenetic and distributional variations. Proximal ray morphology varies substantially with size in P. cubensis and P. orthotriremis. A. balanoides generally occurs in deeper water in the Lesser Antilles than in the Bahamas and Strait of Florida, while P. orthotriremis occurs in shallower water in the Lesser Antilles and deeper in the Bahamas.

  1. Systematics and zoogeography of Asteroidea (Echinodermata) from Inhaca Island, Mozambique

    NARCIS (Netherlands)

    Walenkamp, J.H.C.

    1990-01-01

    Sixteen out of the seventeen species of shallow-water starfishes reported with certainty from Inhaca Island and Maputo Bay were collected by the author. The seventeenth, Archaster angulatus, was recorded from there by Jangoux (1973). An identification key to these species, both in English and in

  2. The oldest synallactid sea cucumber (Echinodermata: Holothuroidea: Aspidochirotida)

    OpenAIRE

    Reich, Mike

    2010-01-01

    Aspidochirote holothurian ossicles were discovered in Upper Ordovician-aged Öjlemyr cherts from Gotland, Sweden. The well-preserved material allows definitive assignment to the family Synallactidae, a deep-sea sea cucumber group that is distributed worldwide today. The new taxon Tribrachiodemas ordovicicus gen. et sp. nov. is described, representing the oldest member of the Aspidochirotida. The further fossil record of Synallactidae and evolutionary implications are also discussed. peerRev...

  3. Origin of the holothurians (Echinodermata derived by constructional morphology

    Directory of Open Access Journals (Sweden)

    R. Haude

    2002-01-01

    Full Text Available According to a recent hypothesis, the holothurians originated by a process of extreme paedomorphism as "giant larvae", with "de novo" developed radial systems. However, the present approach, which follows the principles of constructional morphology, supports former views that the holothurian predecessor must have been echinoid-like. After constitution of a (reliable early predecessor construction as a model with machine analogies, subsequent steps of structural transformation are explained by functional improvement and economy. Following results are discussed: (i Holothurians have to be derived from a postlarval precursor; (ii "Apodida" (as molecular-genetically derived first holothurians must originally have been pedate; (iii ophiocistioids would not be cladistic “holothurians” but a precursor construction of the taxon echinoids plus holothurians; (iv the Lovenian structure of the calcareous ring of Nudicorona (Middle Devonian, possible radial series in Palaeocucumaria (Lower Devonian, and distribution of the podia in two new holothurian body fossils from the Lower and Middle Devonian (preliminary description as Prokrustia tabulifera n. gen., n. sp. and Podolepithuria walliseri n. gen., n. sp. obviously corroborate homology of holothurian and other echinoderm radial systems; (v different extent of podial and body wall skeletonization suggests the existence of respiratory trees by no later than the Middle Devonian. Nach einer neueren Erklärung, die sich auf eine Theorie zur Homologisierung von larvalen und adulten Strukturen von Echinodermen stützt, sollen die Holothurien über extreme Paedomorphose, d.h. über „Riesen-Larven” mit neugebildeten postoralen Radial-Systemen entstanden sein. Dagegen läßt sich anhand eines konstruktions-morphologischen Verfahrens zeigen, daß Holothurien auf einen Echiniden-artigen Vorläufer zurückzuführen sind. So wird zunächst eine (wahrscheinliche frühe Vorläufer-Konstruktion der Echinozoen nach Maschinen-Analogien konstituiert. Die daran anschließenden strukturellen Transformationen werden nach funktionellen und energetischen Kriterien begründet. Sie führen zwanglos zu Konstruktionen, die nicht nur rezenten Formen entsprechen, sondern offensichtlich auch durch bekannte und neue paläozoische Fossilien bestätigt werden. Im Einzelnen werden folgende Ergebnisse zur Diskussion gestellt: (i Holothurien sind von einer post-larvalen Vorläufer-Konstruktion abzuleiten; (ii die füßchenlosen „Apodida” (als molekulargenetisch früheste Holothurien müssen zunächst vollständige Radien mit Podia besessen haben; (iii bei den (nur paläozoischen Ophiocistioiden handelt es sich nicht kladistisch um „Holothurien”, sondern sie repräsentieren eine Vorläufer-Konstruktion des Taxon Echiniden plus Holothurien; (iv die Loven'sche Struktur des Schlundrings von Nudicorona (Mittel-Devon, die möglicherweise radialen Strukturen bei Palaeocucumaria (Unter-Devon und die Verteilung der Podia in zwei neuen, vollständig erhaltenen Holothurien aus dem Unter- und Mittel-Devon (vorläufige Beschreibung als Prokrustia tabulifera n. gen., n. sp. und Podolepithuria walliseri n. gen., n. sp. stützen die konstruktions-morphologische Begründung der Homologie der Radial-Systeme bei Holothurien und den übrigen Echinodermen; (v das deutlich unterschiedliche Ausmaß der Skelettierung von Podia bei den neuen Holothurien-Funden scheint anzudeuten, daß die analen Respirations-Strukturen der Holothurien spätestens ab dem Mittel-Devon vorhanden sind. doi:10.1002/mmng.20020050110

  4. Seasonal changes in biochemical composition of Holothuria leucospilota (Echinodermata)

    Digital Repository Service at National Institute of Oceanography (India)

    Jayasree, V.; Parulekar, A.H.; Wahidullah, S.; Kamat, S.Y.

    Biochemical composition of body wall and gonads of Holothuria leucospilota was analysed for protein, carbohydrate, lipid, ash, dry weight and calorific values and was discussed in relation to its spawning activities. Lipids constituted the major...

  5. Water transport by the renal Na(+)-dicarboxylate cotransporter

    DEFF Research Database (Denmark)

    Meinild, A K; Loo, D D; Pajor, A M

    2000-01-01

    This study investigated the ability of the renal Na(+)-dicarboxylate cotransporter, NaDC-1, to transport water. Rabbit NaDC-1 was expressed in Xenopus laevis oocytes, cotransporter activity was measured as the inward current generated by substrate (citrate or succinate), and water transport...... was monitored by the changes in oocyte volume. In the absence of substrates, oocytes expressing NaDC-1 showed an increase in osmotic water permeability, which was directly correlated with the expression level of NaDC-1. When NaDC-1 was transporting substrates, there was a concomitant increase in oocyte volume....... This solute-coupled influx of water took place in the absence of, and even against, osmotic gradients. There was a strict stoichiometric relationship between Na(+), substrate, and water transport of 3 Na(+), 1 dicarboxylate, and 176 water molecules/transport cycle. These results indicate that the renal Na...

  6. Intracellular Na(+) and metabolic modulation of Na/K pump and excitability in the rat suprachiasmatic nucleus neurons.

    Science.gov (United States)

    Wang, Yi-Chi; Yang, Jyh-Jeen; Huang, Rong-Chi

    2012-10-01

    Na/K pump activity and metabolic rate are both higher during the day in the suprachiasmatic nucleus (SCN) that houses the circadian clock. Here we investigated the role of intracellular Na(+) and energy metabolism in regulating Na/K pump activity and neuronal excitability. Removal of extracellular K(+) to block the Na/K pump excited SCN neurons to fire at higher rates and return to normal K(+) to reactivate the pump produced rebound hyperpolarization to inhibit firing. In the presence of tetrodotoxin to block the action potentials, both zero K(+)-induced depolarization and rebound hyperpolarization were blocked by the cardiac glycoside strophanthidin. Ratiometric Na(+) imaging with a Na(+)-sensitive fluorescent dye indicated saturating accumulation of intracellular Na(+) in response to pump blockade with zero K(+). The Na(+) ionophore monensin also induced Na(+) loading and hyperpolarized the membrane potential, with the hyperpolarizing effect of monensin abolished in zero Na(+) or by pump blockade. Conversely, Na(+) depletion with Na(+)-free pipette solution depolarized membrane potential but retained residual Na/K pump activity. Cyanide inhibition of oxidative phosphorylation blocked the Na/K pump to depolarize resting potential and increase spontaneous firing in most cells, and to raise intracellular Na(+) levels in all cells. Nonetheless, the Na/K pump was incompletely blocked by cyanide but completely blocked by iodoacetate to inhibit glycolysis, indicating the involvement of both oxidative phosphorylation and glycolysis in fueling the Na/K pump. Together, the results indicate the importance of intracellular Na(+) and energy metabolism in regulating Na/K pump activity as well as neuronal excitability in the SCN neurons.

  7. Presoja notranjih kontrol pri obračunu davka na dodano vrednost na primeru "Podjetja x"

    OpenAIRE

    Majcen, Borut

    2016-01-01

    Poslovanje podjetja si je ob odsotnosti notranjih kontrol nemogoče predstavljati. Podjetja so podvržena raznim tveganjem, še posebej v današnjih razmerah globalnega poslovanja, ko se podjetja soočajo z vedno novimi izzivi, kar prinaša tudi nova tveganja. Najučinkovitejši ukrep za obvladovanje tveganj predstavlja vzpostavitev sistema notranjih kontrol. Obvladovanje tveganj pa ne poteka samo na ravni podjetja kot celote, ampak je prisotno na vseh področjih delovanja podjetja, torej tudi na p...

  8. (1) Na-Allah et al

    African Journals Online (AJOL)

    Adeyinka Odunsi

    Na-Allah, Y., Zamnao, A. *Garba, S. and Abdullahi, A. U.. Department of Animal Science, Faculty of Agriculture,. Usmanu Danfodiyo University, P. M. B. 2346, Sokoto-Nigeria. *Corresponding author: email; sanigarba2003@yahoo.com Phone no. +234(0)8067090255. Abstract. This study evaluated the pre-‐weaning growth ...

  9. Habitus professoral na sala de aula virtual

    Directory of Open Access Journals (Sweden)

    Alexandre Marinho Pimenta

    2014-09-01

    Full Text Available Entendendo que a indiferença na ação pedagógica contribui para a reprodução das desigualdades no sistema de ensino, o presente artigo busca captar, a partir de entrevistas semiestruturadas, traços do habitus de professores supervisores de disciplinas do curso de Licenciatura em Pedagogia na modalidade a distância na Universidade de Brasília - UnB no âmbito do Sistema Universidade Aberta do Brasil - UAB. As orientações metodológicas de Bourdieu (2007 foram um dos elementos orientadores na análise das entrevistas, considerando ainda o uso heurístico do conceito de habitus. Conclui-se que o habitus professoral envolve esforços voluntários em busca de uma ação pedagógica diferenciada. No entanto, ele é ambíguo e condescendente frente aos limites do modelo de EaD no âmbito da UAB. Ao fim, os dados analisados permitem fornecer elementos para reorientação político-pedagógica que vise a um novo modelo de EaD nacional.

  10. Le Hodler d'Iéna

    OpenAIRE

    2017-01-01

    Suites de la protestation contre le bombardement de la cathédrale de Reims. Nouvelle proposition de M. Gunsburger pour le rachat du tableau de Hodler "Départ des étudiants d'Iéna pour la guerre de libération contre Napoléon en 1813".

  11. Study of deconfinement in NA50

    Indian Academy of Sciences (India)

    Corrado Cicalo

    from the forward hadronic energy measured in the very forward hadronic calorimeter. 2. Experimental setup and data selection. The NA50 apparatus [6] mainly consists of a muon spectrometer, a segmented active target and three independent centrality detectors: an electromagnetic calorimeter which measures the neutral ...

  12. Pijn tijdens of na de wortelkanaalbehandeling

    NARCIS (Netherlands)

    Wesselink, P.R.

    2012-01-01

    Een wortelkanaalbehandeling kan pijn veroorzaken tijdens en/of na de behandeling. Tijdens de behandeling moet dan onderscheid worden gemaakt tussen pijn bij een pulpitis en pijn bij een necrotische pulpa. In beide gevallen kan die pijn effectief worden bestreden, afhankelijk van de toestand waarin

  13. Leitura na escola: um barco à deriva?

    Directory of Open Access Journals (Sweden)

    Teixeira, Marlene

    2008-01-01

    Full Text Available Este artigo busca, na teoria da enunciação de É. Benveniste, elementos para repensar o trabalho com a leitura na escola. Considera que, na discussão das noções gêmeas de forma e sentido, o autor formula uma concepção de significado que, de um lado, pode deter a interpretação à deriva, implicada na visão de leitura centrada no leitor, e, de outro lado, possibilita que se transcenda a idéia de que é pela decifração mdo código que se dá o processo de construção do significado. Conclui que, no processo de leitura, é sempre de um trabalho com a língua que se trata, trabalho que se renova a cada ato de aproximação do aluno com o texto, porque a língua é submetida ao ato de enunciação

  14. NA49: lead-lead collision

    CERN Multimedia

    1996-01-01

    This is an image of an actual lead ion collision taken from tracking detectors on the NA49 experiment, part of the heavy ion project at CERN. These collisions produce a very complicated array of hadrons as the heavy ions break up. It is hoped that one of these collisions will eventually create a new state of matter known as quark-gluon plasma.

  15. Nucleotide binding to Na+/K+-ATPase

    Czech Academy of Sciences Publication Activity Database

    Kubala, Martin; Lánský, Zdeněk; Ettrich, R.; Plášek, J.; Teisinger, Jan; Amler, Evžen

    2005-01-01

    Roč. 272, č. S1 (2005), s. 191-191 E-ISSN 1742-4658. [FEBS Congress /30./ and IUBMB Conference /9./. 02.07.2005-07.07.2005, Budapest] Keywords : Na+/K+- ATPase * ATP binding * TNP-ATP Subject RIV: BO - Biophysics

  16. Therapy of hyperthyroidism with Na131I

    International Nuclear Information System (INIS)

    Kakehi, Hirotake; Furukawa, Takashi; Fukakusa, Shunichi; Futonaka, Hiroshi; Takahashi, Yuji

    1984-01-01

    Forty one patients of hyperthyroidism were treated with Na 131 I. Men and women are in the ratio 1:3.1. The ages of patients are between twenties and sixties and the forties are the highest in number. The observation period of clinical courses is between 1 and 8 years. The number of patients observed over 5 years are 51% of them and over 2 years are 83%. The treatment frequency is as follows: On 37 cases each one was treated once with Na 131 I. 2 cases twice, 1 case at 4 times in 3 years and 1 case at 5 times in 6 years. The treatment doses are between 4,000-6,000 rad (40-60 Gray). In the cases treated with the irradiation dose of 6,000 rad, we often saw hypothyroidism. In cases aiming 4,000-5,000 rad, there is a tendency of leaving hyperthyroidism unrecovered. In conclusion, the patients should be treated giving 4,000-5,000 rad or with Na 131 I doses of 3-6mCi. If the effects of the treatment are insufficient, the patients should be further treated with anti-thyroid drug or treated again with Na 131 I. As the result, there are at present 25 cases (61.0%) in normal status of the thyroid gland, 12 cases (29.2%) in hyperthyroidism and 4 cases (9.8%) in hypothyroidism totaling 41 cases in all. (author)

  17. NA48: Wiring up for Change

    CERN Multimedia

    2001-01-01

    The NA48 Collaboration is rebuilding its drift chambers ready for the experiment to start up again this coming July. An intricate task involving the soldering of over 24,000 wires! The future of the NA48 experiment is coming right down to the wire, that is, the wires which the Collaboration is installing in the clean room of Hall 887 on the Prévessin site. Six days a week, technicians are working in shifts to rebuild the experiment's drift chambers. The original chambers were damaged when a section of a vacuum tube imploded at the end of 1999. A year ago, CERN gave the green light for this essential part of the spectrometer to be rebuilt, so the NA48 experiment, which studies CP violation (see box), still has a bright future ahead of it. Three years of data-taking ahead The NA48 experiment aims to penetrate the secrets of CP (Charge Parity) violation. Charge and parity are two parameters which distinguish a particle from an antiparticle. In other words, an electron possesses a negative electric ...

  18. Study of deconfinement in NA50

    Indian Academy of Sciences (India)

    Corrado Cicalo

    The anomalous J/ψ pattern suppression observed in NA50 experiment is a clear evidence of the transition to a deconfined state of matter. Acknowledgements. This work was partially supported by Fundaç˜ao para a Ciência e a Tecnologia, by INTAS grant 96-0231 and by the Russian Foundation for Fundamental Research, ...

  19. New articulated asteroids (Echinodermata, Asteroidea and ophiuroids (Echinodermata, Ophiuroidea from the Late Jurassic (Volgian / Tithonian of central Spitsbergen

    Directory of Open Access Journals (Sweden)

    Julie Rousseau

    2018-03-01

    Full Text Available The Late Jurassic–Early Cretaceous Slottsmøya Member of the Agardhfjellet Formation in central Spitsbergen has yielded two new species of asteroids and two species of ophiuroids, one of which is described as new. Polarasterias janusensis Rousseau & Gale gen. et sp. nov. is a forcipulatid neoasteroid with elongated arms, small disc and very broad ambulacral grooves with narrow adambulacrals. Savignaster septemtrionalis Rousseau & Gale sp. nov. is a pterasterid with well-developed interradial chevrons. The Spitsbergen specimens are the first described articulated material of Savignaster and reveal the overall arrangement of the ambulacral groove ossicles. Ophiogaleus sp. is an ophiacanthid with relatively long jaws and lateral arm plates, with a coarsely reticulate outer surface. Here again, we report the first articulated skeletons of this genus, providing unprecedented insights into the disc morphology. Ophioculina hoybergia Rousseau & Thuy gen. et sp. nov. is an ophiopyrgid with a well-developed arm comb and tentacle pores reduced to within-plate perforations starting at median arm segments. These new finds are important additions to the asterozoan fossil record with regard to their good degree of articulation and the high latitudinal position of the localities. They significantly add to the set of exhaustively known fossil asterozoan taxa which play a key role in the phylogenetic analysis and reconstruction of evolutionary history.

  20. Zasvojenost z igrami na srečo : magistrsko delo

    OpenAIRE

    Rozman, Patricia

    2014-01-01

    Namen magistrske naloge je predstaviti eno izmed najbolj skritih oblik zasvojenosti, to je zasvojenost z igrami na srečo. Zanimalo me je, kako ta oblika zasvojenosti vpliva na posameznika, tako telesno kot duševno. Ali posameznikova zasvojenost vpliva na ljudi okoli njega, na njegovo družino, prijatelje, znance in službo, ter kako se zasvojenec s tem sooča. Predvsem me je zanimalo, ali zasvojenost z igrami na srečo vodi v kriminalna dejanja in kakšna so ta dejanja ter kako je to ureje...

  1. VPLIV BARVE EMBALAŽE NA ZAZNAVANJE OKUSA GOSTEGA SOKA

    OpenAIRE

    Prevolšek, Daša

    2016-01-01

    Z barvami se srečujemo na vsakem koraku. Mogoče se njihovega vpliva ne zavedamo povsem, vendar nam lahko že pogled na določeno barvo dvigne ali pokvari razpoloženje. Barve imajo zelo velik vpliv na človeka in v nas prebujajo različna čustva. Nekatere barve so pozitivne in nas osrečujejo, druge pa na nas delujejo negativno. Ravno zaradi tega je tudi za oblikovalce embalaže zelo pomembno, da vnaprej predvidijo, kako se bodo potencialni porabniki njihovega izdelka odzivali na njihovo embalažo. P...

  2. IZOBRAŽEVANJE NA DOMU - ŠTUDIJA PRIMERA

    OpenAIRE

    Križan, Urška

    2014-01-01

    V teoretičnem delu se skozi literaturo seznanjamo z zakoni, ki na območju Republike Slovenije urejajo izobraževanje na domu, pa tudi s smernicami, ki veljajo na področju organiziranosti takega pouka. Po enem tednu, ki smo ga preživeli na domačiji skupaj s tremi šoloobveznimi otroki, ki se šolajo na domu, ugotavljamo, da je izvajanje izobraževanja na domu zmeraj v skladu z zakoni in pogosto v skladu s smernicami.

  3. Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton.

    Science.gov (United States)

    Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A Egrinya; Li, Weijiang

    2012-03-01

    A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100 mM) or non-uniform NaCl concentrations (0/200 and 50/150 mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na(+) concentrations in leaves. The [Na(+)] in the '0' side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the '0' side phloem was girdled, suggesting that the increased [Na(+)] in the '0' side roots was possibly due to transportation of foliar Na(+) to roots through phloem. Plants under non-uniform salinity extruded more Na(+) from the root than those under uniform salinity. Root Na(+) efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na(+) efflux and H(+) influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na(+) extrusion was probably due to active Na(+)/H(+) antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na(+) concentration, transport of excessive foliar Na(+) to the low salinity side, and enhanced Na(+) efflux from the low salinity root.

  4. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    Science.gov (United States)

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-07-01

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO 2 and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 °C for 2-6 h by changing the SiO 2/Al 2O 3, H 2O/Na 2O and Na 2O/SiO 2 molar ratios of precursors in the two-step process. The surface area and NH 4+-cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m 2/g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m 2/g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of ˜3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously.

  5. Batrachotoxin-activated Na+ channels in planar lipid bilayers. Competition of tetrodotoxin block by Na+.

    Science.gov (United States)

    Moczydlowski, E; Garber, S S; Miller, C

    1984-11-01

    Single Na+ channels from rat skeletal muscle plasma membrane vesicles were inserted into planar lipid bilayers formed from neutral phospholipids and were observed in the presence of batrachotoxin. The batrachotoxin-modified channel activates in the voltage range -120 to -80 mV and remains open almost all the time at voltages positive to -60 mV. Low levels of tetrodotoxin (TTX) induce slow fluctuations of channel current, which represent the binding and dissociation of single TTX molecules to single channels. The rates of association and dissociation of TTX are both voltage dependent, and the association rate is competitively inhibited by Na+. This inhibition is observed only when Na+ is increased on the TTX binding side of the channel. The results suggest that the TTX receptor site is located at the channel's outer mouth, and that the Na+ competition site is not located deeply within the channel's conduction pathway.

  6. High-temperature phases of NaNbO3 and NaTaO3.

    Science.gov (United States)

    Darlington; Knight

    1999-02-01

    The high-temperature phases of the perovskites sodium niobate, NaNbO(3), and sodium tantalate, NaTaO(3), have been re-examined using the high-resolution powder diffractometer HRPD at the ISIS neutron spallation source; the two materials show the same sequence of phases with tilted octahedra. Diffraction patterns were measured every 5 K allowing structural changes with temperature within a single phase to be determined for the first time. Previous structure determinations within one phase had been performed at a single temperature only. The octahedra are tilted about pseudocubic directions and are also deformed; the magnitude of the deformation is shown to be proportional to the square of the angle of tilt as expected from a phenomenological theory applied to such transitions. The structures of NaNbO(3) between 753 and 793 K and of NaTaO(3) below 758 K are not as reported in the literature.

  7. Transmural gradients in Na/K pump activity and [Na+]I in canine ventricle.

    Science.gov (United States)

    Gao, J; Wang, W; Cohen, I S; Mathias, R T

    2005-09-01

    There are well-documented differences in ion channel activity and action potential shape between epicardial (EPI), midmyocardial (MID), and endocardial (ENDO) ventricular myocytes. The purpose of this study was to determine if differences exist in Na/K pump activity. The whole cell patch-clamp was used to measure Na/K pump current (I(P)) and inward background Na(+)-current (I(inb)) in cells isolated from canine left ventricle. All currents were normalized to membrane capacitance. I(P) was measured as the current blocked by a saturating concentration of dihydro-ouabain. [Na(+)](i) was measured using SBFI-AM. I(P)(ENDO) (0.34 +/- 0.04 pA/pF, n = 17) was smaller than I(P)(EPI) (0.68 +/- 0.09 pA/pF, n = 38); the ratio was 0.50 with I(P)(MID) being intermediate (0.53 +/- 0.13 pA/pF, n = 19). The dependence of I(P) on [Na(+)](i) or voltage was essentially identical in EPI and ENDO (half-maximal activation at 9-10 mM [Na(+)](i) or approximately -90 mV). Increasing [K(+)](o) from 5.4 to 15 mM caused both I(P)(ENDO) and I(P)(EPI) to increase, but the ratio remained approximately 0.5. I(inb) in EPI and ENDO were nearly identical ( approximately 0.6 pA/pF). Physiological [Na(+)](i) was lower in EPI (7 +/- 2 mM, n = 31) than ENDO (12 +/- 3 mM, n = 29), with MID being intermediate (9 +/- 3 mM, n = 22). When cells were paced at 2 Hz, [Na(+)](i) increased but the differences persisted (ENDO 14 +/- 3 mM, n = 10; EPI 9 +/- 2 mM, n = 10; and MID intermediate, 11 +/- 2 mM, n = 9). Based on these results, the larger I(P) in EPI appears to reflect a higher maximum turnover rate, which implies either a larger number of active pumps or a higher turnover rate per pump protein. The transmural gradient in [Na(+)](i) means physiological I(P) is approximately uniform across the ventricular wall, whereas transporters that utilize the transmembrane electrochemical gradient for Na(+), such as Na/Ca exchange, have a larger driving force in EPI than ENDO.

  8. Isotope separation of 22Na and 24Na with using light induced drift effect

    International Nuclear Information System (INIS)

    Hradecny, C.; Tethal, T.; Ermolaev, I.M.; Zemlyanoj, S.G.; Zuzaan, P.

    1993-01-01

    The LIDIS (Light Drift Isotope Separation) separator without a gas flow is discussed. It is shown, that atomization degree of the separated isotopes limited real separation coefficient. The better buffer gas purification allowed to increase the experimental separation factor of 22 Na and 24 Na isotopes up to 25. The new experimental set up allow to increase the separation efficiency up to 50%. 12 refs.; 5 figs

  9. Intracellular Na+ regulation of Na+ pump sites in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Allen, J.C.; Navran, S.S.; Seidel, C.L.; Dennison, D.K.; Amann, J.M.; Jemelka, S.K.

    1989-01-01

    Enzymatically dispersed cells from canine saphenous vein and femoral artery were grown in fetal calf serum and studied at day 0 (freshly dispersed) through confluence in primary culture. Intracellular Na levels (Nai), but not intracellular K (Ki), were increased after 24 h in culture and then decreased to a steady state by 4 days. Na+ pump site number [( 3 H] ouabain binding) increased through day 3 and remained elevated. Nai was still elevated at 2 days when the Na+ pump site number began to increase. Total pump turnover (maximum ouabain-inhibited 86 Rb uptake) reflected the increase in Na+ pump site number. These key events precede the observed increases in both protein production and cellular proliferation. If the same cells are maintained in defined medium, without fetal calf serum, Nai, Ki, and the number of [ 3 H]ouabain binding sites do not change with time. These data are consistent with the suggestion that the initial mitogenic response of vascular smooth muscle cells to fetal calf serum involves an increased Na+ influx, and a Nai accumulation, caused by low Na+ pump density. The synthesis of new pump sites effects a decrease in the accumulated Nai, which may be related to cell proliferation

  10. Na+-NQR (Na+-translocating NADH:ubiquinone oxidoreductase) as a novel target for antibiotics.

    Science.gov (United States)

    Dibrov, Pavel; Dibrov, Elena; Pierce, Grant N

    2017-09-01

    The recent breakthrough in structural studies on Na+-translocating NADH:ubiquinone oxidoreductase (Na+-NQR) from the human pathogen Vibrio cholerae creates a perspective for the systematic design of inhibitors for this unique enzyme, which is the major Na+ pump in aerobic pathogens. Widespread distribution of Na+-NQR among pathogenic species, its key role in energy metabolism, its relation to virulence in different species as well as its absence in eukaryotic cells makes this enzyme especially attractive as a target for prospective antibiotics. In this review, the major biochemical, physiological and, especially, the pharmacological aspects of Na+-NQR are discussed to assess its 'target potential' for drug development. A comparison to other primary bacterial Na+ pumps supports the contention that NQR is a first rate prospective target for a new generation of antimicrobials. A new, narrowly targeted furanone inhibitor of NQR designed in our group is presented as a molecular platform for the development of anti-NQR remedies. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Active transport of Na/sup +/ by reconstituted Na,K-ATPase

    Energy Technology Data Exchange (ETDEWEB)

    Boldyrev, A.A.; Svinukhova, I.A.

    1987-02-20

    The ability of ATP, CTP, ITP, GTP, and UTP to support ouabain-sensitive accumulation of Na/sup +/ by proteoliposomes with a reconstituted Na/K-pump was investigated. At a low (Na/sup +/)/(K/sup +/) ratio in the medium (20 mM/50 mM), a correlation is observed between the proton-accepting capacity of the nucleotide and its effectiveness as a substrate of active transport. To test the hypothesis of the importance of the presence of a negative charge in the 1-position of the purine (3-pyrimidine) base of the nucleotide for mutual transitions between the Na- and K-conformations of Na,K-ATPase they used two analogs of ATP: N/sub 1/-hydroxy-ATP, possessing proton acceptor capacity, and N/sub 1/-methoxy-ATP, in the molecule of which the negative charge is quenched by a methyl group. The first substrate supports active accumulation of Na/sup +/ in proteoliposomes at the same rate as ATP, whereas the second substrate is relatively ineffective.

  12. Hidroginástica na terceira idade

    Directory of Open Access Journals (Sweden)

    Karla Campos de Paula

    1998-02-01

    Full Text Available O processo de envelhecimento no indivíduo saudável está relacionado com inúmeras alterações psicológicas e físicas que interferem na área motora, concorrendo para a inatividade e contribuindo para o aparecimento e agravamento de determinadas doenças, além de influenciar negativamente a realização das atividades de vida diária. Portanto, a prática de atividade física é fundamental para o idoso, não só na prevenção de doenças como na reabilitação de suas habilidades motoras, promovendo um estilo de vida saudável que é fator preponderante para a melhoria da qualidade de vida. Contudo, algumas precauções devem ser adotadas na prescrição da atividade direcionada para o idoso, a fim de que esta seja segura e prazerosa. Dentre os exercícios mais adequados aos idosos estão a caminhada, o ciclismo, a natação e a hidroginástica. Devido a sua grande procura, a hidroginástica vem aumentando o número de adeptos na terceira idade. Ela propicia ao idoso o aumento de sua capacidade aeróbia, força muscular, flexibilidade articular e o treinamento de habilidades específicas como equilíbrio e coordenação motora. Soma-se ainda o fato de esta atividade oferecer ambiente de relaxamento e incentivo ao contato social, atuando no combate ao estresse, depressão, na melhoria da autopercepção corporal e da auto-estima. Devemos, então, estar atentos às particularidades da hidroginástica, a fim de aproveitar todas as vantagens que esta oferece para o programa de exercícios direcionado para a terceira idade.

  13. Agmag Igbo dka Ngwar n'kwalite Ezi Nchekwa na Nkwsiike haobodo

    African Journals Online (AJOL)

    Ka Najira nwerechara onwe ya n'af 1960, olileanya tt mamala ya b na ihe ga-adz mma. Mana ka oge na-aga, a chptara na ihe na-akawanye nj. Usoro chch d iche iche daptara. Nd am na nd nkt achala mana nd gara n'ihu na-akawanye nj. O bu ihe doro anya na chch ha b nke nchgbu na fnfju akpa. N'agbanyegh na ...

  14. Transport of Na48 Drift Chambers to Dubna

    CERN Multimedia

    GOLOVATYUK, V

    2010-01-01

    On 22 July, in the occasion of the departure of the Na48 Drift Chambers from CERN, Mikhail Itkis (acting Director of the JIINR) and Rolf Heuer (CERN Director General) visited the NA62 experimental area.

  15. A dataset comprising 141 magnetic resonance imaging scans of 98 extant sea urchin species.

    Science.gov (United States)

    Ziegler, Alexander; Faber, Cornelius; Mueller, Susanne; Nagelmann, Nina; Schröder, Leif

    2014-01-01

    Apart from its application in human diagnostics, magnetic resonance imaging (MRI) can also be used to study the internal anatomy of zoological specimens. As a non-invasive imaging technique, MRI has several advantages, such as rapid data acquisition, output of true three-dimensional imagery, and provision of digital data right from the onset of a study. Of particular importance for comparative zoological studies is the capacity of MRI to conduct high-throughput analyses of multiple specimens. In this study, MRI was applied to systematically document the internal anatomy of 98 representative species of sea urchins (Echinodermata: Echinoidea). The dataset includes raw and derived image data from 141 MRI scans. Most of the whole sea urchin specimens analyzed were obtained from museum collections. The attained scan resolutions permit differentiation of various internal organs, including the digestive tract, reproductive system, coelomic compartments, and lantern musculature. All data deposited in the GigaDB repository can be accessed using open source software. Potential uses of the dataset include interactive exploration of sea urchin anatomy, morphometric and volumetric analyses of internal organs observed in their natural context, as well as correlation of hard and soft tissue structures. The dataset covers a broad taxonomical and morphological spectrum of the Echinoidea, focusing on 'regular' sea urchin taxa. The deposited files significantly expand the amount of morphological data on echinoids that are electronically available. The approach chosen here can be extended to various other vertebrate and invertebrate taxa. We argue that publicly available digital anatomical and morphological data gathered during experiments involving non-invasive imaging techniques constitute one of the prerequisites for future large-scale genotype-phenotype correlations.

  16. Angiotensin II-induced hypertension increases plasma membrane Na pump activity by enhancing Na entry in rat thick ascending limbs.

    Science.gov (United States)

    Gonzalez-Vicente, Agustin; Garvin, Jeffrey L

    2013-11-01

    Thick ascending limbs (TAL) reabsorb 30% of the filtered NaCl load. Na enters the cells via apical Na-K-2Cl cotransporters and Na/H exchangers and exits via basolateral Na pumps. Chronic angiotensin II (ANG II) infusion increases net TAL Na transport and Na apical entry; however, little is known about its effects on the basolateral Na pump. We hypothesized that in rat TALs Na pump activity is enhanced by ANG II-infusion, a model of ANG II-induced hypertension. Rats were infused with 200 ng·kg(-1)·min(-1) ANG II or vehicle for 7 days, and TAL suspensions were obtained. We studied plasma membrane Na pump activity by measuring changes in 1) intracellular Na (Nai) induced by ouabain; and 2) ouabain-sensitive oxygen consumption (QO2). We found that the ouabain-sensitive rise in Nai in TALs from ANG II-infused rats was 12.8 ± 0.4 arbitrary fluorescent units (AFU)·mg(-1)·min(-1) compared with only 9.9 ± 1.1 AFU·mg(-1)·min(-1) in controls (P Na pump expression, the number of Na pumps in the plasma membrane, or the affinity for Na. When furosemide (1.1 mg·kg(-1)·day(-1)) was coinfused with ANG II, no increase in plasma membrane Na pump activity was observed. We concluded that in ANG II-induced hypertension Na pump activity is increased in the plasma membrane of TALs and that this increase is caused by the chronically enhanced Na entry occurring in this model.

  17. Rescue of Na+ affinity in aspartate 928 mutants of Na+,K+-ATPase by secondary mutation of glutamate 314.

    Science.gov (United States)

    Holm, Rikke; Einholm, Anja P; Andersen, Jens P; Vilsen, Bente

    2015-04-10

    The Na(+),K(+)-ATPase binds Na(+) at three transport sites denoted I, II, and III, of which site III is Na(+)-specific and suggested to be the first occupied in the cooperative binding process activating phosphorylation from ATP. Here we demonstrate that the asparagine substitution of the aspartate associated with site III found in patients with rapid-onset dystonia parkinsonism or alternating hemiplegia of childhood causes a dramatic reduction of Na(+) affinity in the α1-, α2-, and α3-isoforms of Na(+),K(+)-ATPase, whereas other substitutions of this aspartate are much less disruptive. This is likely due to interference by the amide function of the asparagine side chain with Na(+)-coordinating residues in site III. Remarkably, the Na(+) affinity of site III aspartate to asparagine and alanine mutants is rescued by second-site mutation of a glutamate in the extracellular part of the fourth transmembrane helix, distant to site III. This gain-of-function mutation works without recovery of the lost cooperativity and selectivity of Na(+) binding and does not affect the E1-E2 conformational equilibrium or the maximum phosphorylation rate. Hence, the rescue of Na(+) affinity is likely intrinsic to the Na(+) binding pocket, and the underlying mechanism could be a tightening of Na(+) binding at Na(+) site II, possibly via movement of transmembrane helix four. The second-site mutation also improves Na(+),K(+) pump function in intact cells. Rescue of Na(+) affinity and Na(+) and K(+) transport by second-site mutation is unique in the history of Na(+),K(+)-ATPase and points to new possibilities for treatment of neurological patients carrying Na(+),K(+)-ATPase mutations. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Characterization of Na+-linked and Na+-independent Cl-/HCO3- exchange systems in Chinese hamster lung fibroblasts

    International Nuclear Information System (INIS)

    Cassel, D.; Scharf, O.; Rotman, M.; Cragoe, E.J. Jr.; Katz, M.

    1988-01-01

    The PS120 variant of Chinese hamster lung fibroblasts which lacks Na + /H + exchange activity was used to investigate bicarbonate transport systems and their role in intracellular pH (pH/sub i/) regulation. When pH/sub i/ was decreased by acid load, bicarbonate caused pH/sub i/ increase and stimulated 36 Cl - efflux from the cells, both in a Na + -dependent manner. These results together with previous findings that bicarbonate stimulates 22 Na + uptake in PS120 cells demonstrate the presence of a Na + -linked Cl - /HCO 3 - exchange system. In cells with normal initial pH/sub i/, bicarbonate caused Na + -independent pH/sub i/ increase in Cl - -free solutions and stimulated Na + -independent 36 Cl - efflux, indicating that a Na + -independent Cl - /HCO 3 - exchanger is also present in the cell. Na + -linked and Na + -independent Cl - /HCO 3- exchange is apparently mediated by two distinct systems, since a [(tetrahydrofluorene-7-yl)oxy]acetic acid derivative selectively inhibits the Na + -independent exchanger. An additional distinctive features is a 10-fold lower affinity for chloride of the Na + -linked exchanger. The Na + -linked and Na + -independent Cl - /HCO 3 - exchange systems are likely to protect the cell from acid and alkaline load, respectively

  19. The two C-terminal tyrosines stabilize occluded Na/K pump conformations containing Na or K ions.

    Science.gov (United States)

    Vedovato, Natascia; Gadsby, David C

    2010-07-01

    Interactions of the three transported Na ions with the Na/K pump remain incompletely understood. Na/K pump crystal structures show that the extended C terminus of the Na,K-adenosine triphosphatase (ATPase) alpha subunit directly contacts transmembrane helices. Deletion of the last five residues (KETYY in almost all Na/K pumps) markedly lowered the apparent affinity for Na activation of pump phosphorylation from ATP, a reflection of cytoplasmic Na affinity for forming the occluded E1P(Na3) conformation. ATPase assays further suggested that C-terminal truncations also interfere with low affinity Na interactions, which are attributable to extracellular effects. Because extracellular Na ions traverse part of the membrane's electric field to reach their binding sites in the Na/K pump, their movements generate currents that can be monitored with high resolution. We report here electrical measurements to examine how Na/K pump interactions with extracellular Na ions are influenced by C-terminal truncations. We deleted the last two (YY) or five (KESYY) residues in Xenopus laevis alpha1 Na/K pumps made ouabain resistant by either of two kinds of point mutations and measured their currents as 10-mM ouabain-sensitive currents in Xenopus oocytes after silencing endogenous Xenopus Na/K pumps with 1 microM ouabain. We found the low affinity inhibitory influence of extracellular Na on outward Na/K pump current at negative voltages to be impaired in all of the C-terminally truncated pumps. Correspondingly, voltage jump-induced transient charge movements that reflect pump interactions with extracellular Na ions were strongly shifted to more negative potentials; this signals a several-fold reduction of the apparent affinity for extracellular Na in the truncated pumps. Parallel lowering of Na affinity on both sides of the membrane argues that the C-terminal contacts provide important stabilization of the occluded E1P(Na3) conformation, regardless of the route of Na ion entry into the

  20. The rapid-onset dystonia parkinsonism mutation D923N of the Na+, K+-ATPase alpha3 isoform disrupts Na+ interaction at the third Na+ site.

    Science.gov (United States)

    Einholm, Anja Pernille; Toustrup-Jensen, Mads S; Holm, Rikke; Andersen, Jens Peter; Vilsen, Bente

    2010-08-20

    Rapid-onset dystonia parkinsonism (RDP), a rare neurological disorder, is caused by mutation of the neuron-specific alpha3-isoform of Na(+), K(+)-ATPase. Here, we present the functional consequences of RDP mutation D923N. Relative to the wild type, the mutant exhibits a remarkable approximately 200-fold reduction of Na(+) affinity for activation of phosphorylation from ATP, reflecting a defective interaction of the E(1) form with intracellular Na(+). This is the largest effect on Na(+) affinity reported so far for any Na(+), K(+)-ATPase mutant. D923N also affects the interaction with extracellular Na(+) normally driving the E(1)P to E(2)P conformational transition backward. However, no impairment of K(+) binding was observed for D923N, leading to the conclusion that Asp(923) is specifically associated with the third Na(+) site that is selective toward Na(+). The crystal structure of the Na(+), K(+)-ATPase in E(2) form shows that Asp(923) is located in the cytoplasmic half of transmembrane helix M8 inside a putative transport channel, which is lined by residues from the transmembrane helices M5, M7, M8, and M10 and capped by the C terminus, recently found involved in recognition of the third Na(+) ion. Structural modeling of the E(1) form of Na(+), K(+)-ATPase based on the Ca(2+)-ATPase crystal structure is consistent with the hypothesis that Asp(923) contributes to a site binding the third Na(+) ion. These results in conjunction with our previous findings with other RDP mutants suggest that a selective defect in the handling of Na(+) may be a general feature of the RDP disorder.

  1. Urgências reprodutivas na cadela

    OpenAIRE

    Costa, Teresa Isabel Rodrigues da

    2010-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária As urgências reprodutivas ocorrem com frequência na prática clínica, estando o seu desfecho favorável associado a um diagnóstico e intervenção céleres. Na cadela, consideram-se urgências reprodutivas a distócia, a piómetra, o prolapso uterino, a torção uterina, a tetania puerperal, a metrite e a mastite. Esta dissertação tem por base a análise dos dados referentes à casuística de urgências reprodutivas em cadelas veri...

  2. Jogos teatrais na escola pública

    Directory of Open Access Journals (Sweden)

    Ricardo Ottoni Vaz Japiassu

    1998-07-01

    Full Text Available O artigo apresenta os resultados parciais de pesquisa etnográfica que acompanha aspectos do desenvolvimento cultural de pré-adolescentes com a linguagem teatral em classe multisseriada, através do ensino regular de Teatro, em escola de ensino fundamental da rede pública estadual de São Paulo-SP. Os dados obtidos permitem afirmar que a linguagem cênica contribui na conscientização das novas possibilidades de significação da palavra na prática discursiva.The article shows partial results of ethnographic research in which kids are observed in their cultural development process with theater classes in public school education in São Paulo/Brazil. The data colected indicates that the use of theater games in school education helps students to be aware of a word’s new meaning possibilities in human comunication.

  3. HUME E O EMPIRISMO NA MORAL

    Directory of Open Access Journals (Sweden)

    Adriano Naves de Brito

    2007-12-01

    Full Text Available O que pretendo defender neste texto é que uma posição empirista na moral é compatível com uma pretensão de validade intersubjetiva de juízos morais. Essa pretensão deve, nesse caso, estar calcada na naturalização dos fundamentos da moralidade, mas tem de conviver com limites acerca da justificação de enunciados de valor. Para defender esse ponto, sirvo-me da filosofia moral de Hume, como ele a expôs no seu texto Uma investigação sobre os princípios da moral. No que diz respeito à filosofia de Hume, o objetivo deste texto é explicitar o caráter empírico seja de seu método de investigação da moral, seja do princípio que para ela ele encontra.

  4. News from the NA61/SHINE experiment

    Science.gov (United States)

    Šuša, Tatjana

    2018-02-01

    The main goals of the NA61/SHINE experiment at the CERN SPS are the search for the critical point of strongly interacting matter and the study of the properties of the onset of deconfinement. These aims are pursued by performing a two-dimensional scan of the phase diagram of strongly interacting matter by varying the momentum and size of the colliding nuclei. This contribution summarises the latest results from the NA61/SHINE experiment, in particular, new results on spectra and yields of ϕ meson in p+p interactions at 40, 80 and 158 GeV/c and K+ and K- production in central Be+Be collisions at mid-rapidity. In addition, results on system size dependence of particle yield ratios and fluctuations are presented.

  5. NA62 experiment at CERN SPS

    Directory of Open Access Journals (Sweden)

    Kozhuharov Venelin

    2014-01-01

    Full Text Available The NA62 experiment at SPS is a continuation of the long standing CERN kaon physics program. The high statistics and the unprecedent precision allow to probe the Standard Model and test the description of the strong interactions at low energy. The final results on the the lepton universality test by measuring the ratio RK = Γ(K+ → e+ν/Γ(K+ → µ+ν and the study of the K± → π±γγ decay are presented. The major goal of the NA62 experiment is to perform a measurement of the Br(K+ → π+νν̄ with a precision of 10% in two years of data taking. The detector setup together with the analysis technique is described.

  6. Luz e tempo na melancolia I

    Directory of Open Access Journals (Sweden)

    Cláudio Soares Braga Furtado

    2009-12-01

    Full Text Available A comparação entre as artes possibilita figurar o tempo como elemento comum entre a gravura renascentista de Dürer, a escultura romana de Laocoonte e o conto de Guimarães Rosa. A partir da leitura dessas artes distantes em forma, meios, época e lugar, descobrem-se mistérios aludidos em sutis sinais, que, se ainda não despertos na consciência criativa, estimulam interpretações. O papel da luz como unificadora das entidades tempo/espaço restabelece o princípio clássico da ut pictura poesis na leitura moderna.

  7. Kaizen: Uma Metodologia Inovadora na Siderurgia

    Directory of Open Access Journals (Sweden)

    Hericson Estanislau Prata

    2017-04-01

    Full Text Available A racionalização do processo produtivo industrial, por meio da redução dos desperdícios e da modernização do processo produtivo, com a adoção do Sistema Toyota de Produção (Produção Enxuta, tem sido adotada por uma parte importante das indústrias no mundo. O objetivo deste artigo é descrever essa metodologia empregada pelo grupo de melhoria de fase intensiva adotado na Vallourec Tubos do Brasil S.A. Como resultado, verificou-se que o processo utilizado para a implantação de mudanças em curto prazo foi a semana intensiva, também conhecida como evento Kaizen na indústria automotiva.

  8. O Personal Trainer na Perspectiva do Marketing

    Directory of Open Access Journals (Sweden)

    Cibele Biehl Bossle

    2011-03-01

    Full Text Available Esse estudo apresenta mapeamento das referências dedicadas à formação do personal trainer em bases de dados eletrônicas. Essa garimpagem revelou baixa produção científica sobre o assunto e mostrou que na literatura sobre personal trainer predominam livros com linguagem corrente no mundo dos negócios. Esses achados nos levaram a indagar sobre a força do discurso físico-empresarial, especialmente o marketing, na constituição desta ocupação profissional. Jeremy Rifkin, Zygmunt Bauman, Paula Sibilia e Denise Sant'Anna permitiram visualizar que o marketing dirigido ao personal trainer tem como tarefa reinventar, ressignificar e "repaginar" esta modalidade de serviço em nome da sobrevivência no disputado mercado da vida ativa.

  9. New NA22 results on correlations

    International Nuclear Information System (INIS)

    De Wolf, E.A.

    1993-01-01

    Recent NA22 results from π + p and K + p inelastic interactions at √s = 22 GeV on invariant-mass and Q 2 -dependence of two- and three-particle factorial cumulants are discussed in relation to earlier intermittency studies. The absence of Bose-Einstein type correlations among identical particles, and too large resonance production rates, are responsible for the strong disagreements of models with intermittency data. 6 figs., 17 refs

  10. NA35: sulphur-gold collision

    CERN Multimedia

    1991-01-01

    In this image the real particles produced by the collision of a 6400 GeV sulphur ion with a gold target can be seen as they pass through a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. The NA35 experiment, which was in operation in the 1980s, was part of CERN's ongoing heavy ion project.

  11. Die Calvinistiese Sondagbeskouing met spesiale verwysing na ...

    African Journals Online (AJOL)

    omver te werp. Aan die ander kant het die orde en vrede in die kerk dit wel ook nodig gemaak om 'n dag vir gebruik van die diens van die Here af te sonder. Calvyn se insigte in verband met die oorgang van die Sabbat na die Sondag, is die insigte wat as die eg reformatoriese behoue gebly het. Haitjema (1961:249) sê in.

  12. Sources of Na for the Io atmosphere

    Science.gov (United States)

    Burnett, D. S.; Ellis, Susan B.; Rice, A.; Epstein, S.

    1993-01-01

    The physics and geology of Io have been extensively studied, but there has been little discussion of the chemistry. Relatively little is known about Io chemistry, but there are constraints. Further, it will be a long time before improvements will result from direct observation, given the severe difficulties with the Galileo mission. Via laboratory simulation experiments, plausible thermochemical and photochemical processes which determine the nature and amounts of surface constituents of Io are explored. The well-known density of Io shows that the planet overall is rocky. Because the orbit of Io is well within the magnetosphere of Jupiter and because Io only has a thin, transient SO2 atmosphere, the surface is continually sputtered with magnetospheric ions. Complex processes ionize and accelerate the Io surface atoms to keV and MeV energies. Remarkably, only S, O, and Na ions were found by Voyager. Sputtering also produces an atomic cloud of Na and S (O not observable) with a trace of K. Both gaseous and solid SO2 are known from spectroscopic studies. A trace of H2S and possibly CO2 are present. Geologic features are interpreted in terms of elemental S, but there is no direct evidence for this constituent. We thus have a rocky planet which does not have rocks on the surface. Our general goal is to understand the cycling of Na, S, and O through the crust and atmosphere on present-day Io and to understand how Io evolved to this state. A specific objective was to determine the phases on the surface which are the source of the Na in the atmosphere of Io.

  13. The NA48 liquid krypton calorimeter

    CERN Document Server

    Gorini, B

    1997-01-01

    The NA48 collaboration goal is to measure the CP violation parameter Re(ɛl/ɛ) at the level of 2 × 10−4. The neutral Kaon decays will be reconstructed by an electromagnetic liquid Krypton calorimeter with fine granularity and a volume almost totally sensible, to obtain excellent position and energy resolution, as well as time resolution. A description of the detector, results from tests of a prototype and the status of the final calorimeter are reported.

  14. Prototype calorimeters for the NA3 experiment

    CERN Multimedia

    1975-01-01

    The NA3 Experiment was set-up on the North Area of the SPS by the CERN/ Ecole Polytechnique/College de France/ Orsay/Saclay Collaboration, to study high transverse momentum leptons and hadrons from hadron collisions. The calorimeters measured the energy of hadrons (prototype on the right) and leptons (prototype on the left). They used a new type of plastic scintillator (plexipop). (see CERN Courier of November 1975) energy (prototype on the right)

  15. Maendeleo ya Fasihi ya Kiswahili ya Watoto nchini Tanzania na ...

    African Journals Online (AJOL)

    Fasihi ya Kiswahili ya watoto kama taaluma haina muda mrefu katika historia ya fasihi ya Kiswahili. Ikilinganishwa na fasihi ya watu wazima ambayo ilianza muda mrefu, na pia tafiti nyingi kufanyika katika mataifa mengi, fasihi ya watoto inaonekana kuwa imetelekezwa kwa muda mrefu kutokana na kutokupewa umuhimu ...

  16. Dhima za Mbinu Linganishi katika Kuhusisha Lugha na Lahaja ...

    African Journals Online (AJOL)

    Lengo la makala hii ni kujadili dhima za Mbinu Linganishi katika kuhusisha lugha na lahaja. Data za makala hii zilikusanywa kwa kutumia mbinu mbalimbali ambazo ni usaili, ushuhudiaji, hojaji na majadiliano katika majopo. Utafiti ulifanyika Tanzania Bara hususan Mkoani Mtwara na Tanzania Visiwani katika maeneo ya ...

  17. Glial Na(+) -dependent ion transporters in pathophysiological conditions.

    Science.gov (United States)

    Boscia, Francesca; Begum, Gulnaz; Pignataro, Giuseppe; Sirabella, Rossana; Cuomo, Ornella; Casamassa, Antonella; Sun, Dandan; Annunziato, Lucio

    2016-10-01

    Sodium dynamics are essential for regulating functional processes in glial cells. Indeed, glial Na(+) signaling influences and regulates important glial activities, and plays a role in neuron-glia interaction under physiological conditions or in response to injury of the central nervous system (CNS). Emerging studies indicate that Na(+) pumps and Na(+) -dependent ion transporters in astrocytes, microglia, and oligodendrocytes regulate Na(+) homeostasis and play a fundamental role in modulating glial activities in neurological diseases. In this review, we first briefly introduced the emerging roles of each glial cell type in the pathophysiology of cerebral ischemia, Alzheimer's disease, epilepsy, Parkinson's disease, Amyotrophic Lateral Sclerosis, and myelin diseases. Then, we discussed the current knowledge on the main roles played by the different glial Na(+) -dependent ion transporters, including Na(+) /K(+) ATPase, Na(+) /Ca(2+) exchangers, Na(+) /H(+) exchangers, Na(+) -K(+) -Cl(-) cotransporters, and Na(+) - HCO3- cotransporter in the pathophysiology of the diverse CNS diseases. We highlighted their contributions in cell survival, synaptic pathology, gliotransmission, pH homeostasis, and their role in glial activation, migration, gliosis, inflammation, and tissue repair processes. Therefore, this review summarizes the foundation work for targeting Na(+) -dependent ion transporters in glia as a novel strategy to control important glial activities associated with Na(+) dynamics in different neurological disorders. GLIA 2016;64:1677-1697. © 2016 Wiley Periodicals, Inc.

  18. Muundo wa Mashairi katika Diwani ya Mnyampala (1965) na Nafasi ...

    African Journals Online (AJOL)

    Makala hii pia inadadisi namna mbinu za kimuundo zilivyofanikisha usawiri na ubainishaji wa falsafa ya mtunzi kuhusu ushairi wa Kiswahili na nafasi ya ushairi katika jamii. Makala imeanza kwa kugusia usuli wa historia ya ushairi wa Kiswahili, historia fupi ya maisha ya Mathias Mnyampala na nadharia yake kuhusu ...

  19. Ujitokezaji wa Viambishi Njeo na Athari zake Kifonolojia katika ...

    African Journals Online (AJOL)

    Chanzo cha data za utafiti huu ni vitabu mbalimbali vinavyohusu lugha ya Shimalila, navyo vimeandikwa na watu mbalimbali wa jamii ya Shimalila ambao malengo yao ni kutafsiri Biblia kutoka katika lugha ya Kiswahili kwenda katika lugha ya Shimalila. Pia, data nyingine zimetokana na hojaji pamoja na usaili wa moja ...

  20. BAKITA NA LUGHA YA KUFUNDISHIA | BAKITA | Kioo cha Lugha

    African Journals Online (AJOL)

    BAKITA NA LUGHA YA KUFUNDISHIA. Baraza la Kiswahili la Taifa BAKITA. Abstract. Makala haya yanatoa maelezo mafupi ya matukio muhimu kuhusu suala la kutumia Kiswahili kama lugha ya kufundishia sekondari na vyuo katika kipindi baina ya mwaka 1967 mpaka 2000. Makala yanaeleza dhima na shughuli za ...

  1. Hadhi ya Kiswahili na watumiaji wake katika utandawazi ...

    African Journals Online (AJOL)

    Katika Taifa la Tanzania, mathalani, Kiswahili kimewakusanya na kuwajumuisha pamoja watu wa makabila zaidi ya 150 – kikitumika kama lugha ya mawasiliano inayoeleweka na watu wote. Hii si ajabu, ikizingatiwa kuwa, kwa silika yake, Kiswahili ni lugha unganishi, yaani yenye hulka ya kuunganisha, na siyo ya ...

  2. Hydrophilic C terminus of Salicornia europaea vacuolar Na/H ...

    Indian Academy of Sciences (India)

    Plant vacuolar Na+/H+ antiporters play important roles in cellular ion homeostasis,vacuolar pH regulation and sequestration of Na+ ions into the vacuole. Previous research showed that hydrophilic C-terminal region of Arabidopsis AtNHX1 negatively regulates the Na+/H+ transporting activity. In this study, we truncated the ...

  3. Fanfiction: uma escrita criativa na web

    Directory of Open Access Journals (Sweden)

    Daniele Alves Alencar

    Full Text Available RESUMO Estudo das fanfictions como uma prática de incentivo à leitura e produção de textos ficcionais na web. Por meio de pesquisa exploratória, bibliográfica e qualitativa foi desenvolvido o assunto para a área daCiência da Informação. Utiliza o site “Nyah! Fanfiction” como fonte de informação sobre as fanfictions e para aplicação de questionáriocomo auxílio na investigação do comportamento dos fanfiqueiros do site. O artigo mostra o que são as fanfictions, descreve a forma diferenciada que o ficwriterl ê o texto original para a produção da história, e apresenta o site “Nyah! Fanfiction” não apenas como depositário de fanfictions, mas também informa como essa prática pode se tornar mais que um passatempo, por explorar a imaginação, estimular a criação de textos, e assim intensificar a prática de leitura e escrita entre os jovens. O assunto estudado ainda é considerado novo na área de Biblioteconomia, portanto se faz necessário o desenvolvimento de mais pesquisas abordando o tema fanfiction.

  4. Cultura Política na Antiguidade

    Directory of Open Access Journals (Sweden)

    José Petrúcio Farias Júnior

    2009-06-01

    Full Text Available

    Pretendemos discutir nesse artigo algumas implicações do termo cultura política na Antiguidade, especificamente, na sociedade romana imperial. Dessa forma, acreditamos que as considerações que apresentaremos a seguir contribuam para reflexão da utilização desse termo, produto das investigações contemporâneas, sobre os estudos das sociedades antigas. Para a historiadora Profa. Dra. Margarida Maria de Carvalho, tais reflexões representam ainda uma lacuna na historiografia concernente a essa temática. Isso posto, discorreremos, inicialmente, sobre o conceito de cultura e seus desdobramentos para, em seguida, refletirmos sobre o viés interpretativo que fundamenta estudos históricos que se desenvolvem sob o beneplácito da linha de pesquisa intitulada História e Cultura Política.

  5. NaI(Tl) response functions

    International Nuclear Information System (INIS)

    Vega C, H. R.; Ortiz R, J. M.; Benites R, J. L.; De Leon M, H. A.

    2015-09-01

    The response functions of a NaI(Tl) detector have been estimated using Monte Carlo methods. Response functions were calculated for monoenergetic photon sources (0.05 to 3 MeV). Responses were calculated for point-like sources and for sources distributed in Portland cement cylinders. The responses were used to calculate the efficiency functions in term of photon energy. Commonly, sources used for calibration are point-like, and eventually sources to be measured have different features. In order to use the calibrated sources corrections due to solid angle, self-absorption and scattering, must be carried out. However, some of these corrections are not easy to perform. In this work, the calculated responses were used to estimate the detector efficiency of point-like sources, and sources distributed in Portland type cement. Samples of Portland paste were prepared and were exposed to photoneutrons produced by a 15 MV linac. Some of the elements in the cement were activated producing γ-emitting radionuclides that were measured with a NaI(Tl) gamma-ray spectrometer, that was calibrated with point-like sources. In order to determine the specific activity in the induced radioisotopes calculated efficiencies were used to make corrections due to the differences between the solid angle, photon absorption and photon scattering in the point-like calibration sources and the sources distributed in cement. During the interaction between photoneutrons and the cement samples three radioisotopes were induced: 56 Mn, 24 Na, and 28 Al. (Author)

  6. A CPL NA SOCIEDADE DO CONHECIMENTO

    Directory of Open Access Journals (Sweden)

    Patrisia Ciancio

    2009-07-01

    online tem sido pensada pela Comunidade dos Países de Língua Portuguesa (CPLP, que registra preocupação com sua entrada na sociedade do conhecimento nas atas das reuniões de chefes de Estado, e seus desdobramentos, ocorridas a cada dois anos. No entanto, faltam projetos concretos a esta proposta. O enquadramento teórico da pesquisa que se apresenta está no terreno flutuante da Lusofonia, que em sua descontinuidade territorial e fragmentação se projeta em alternativas “tecnoculturais”. As missões colonizadoras pontilharam um trajeto invisível. Esfera que, de algum modo, persiste e pode ser restaurada na criação de comunidades virtuais com uso de novas tecnologias para refazer este percurso, agora em concepção inversa, que privilegia o mosaico cultural dos povos. Um círculo virtual que pede por ser também virtuoso. O objetivo é delimitar bases para uma proposta prática de criação de novos canais de interação. Para alcançar tais constatações, a metodologia empregada foi uma análise documental que verifica os debates ao redor da comunicação ao longo de dez anos (1996 a 2006 na CPLP.

  7. NA64 Search for Dark Photons

    CERN Document Server

    Shiakas, Christos

    2017-01-01

    The NA64 experiment, known as P348 before official approval, was proposed to the CERN SPSC on January 2014 with main goal the search for the following decay modes A′ → invisible A′ → e−e+ (1) In March 2016 P348 was granted approval by the CERN Research Board and received the title NA64. Since having been promoted, the experiment has been conducting the searches the searches for the processes mentioned above at the CERN SPS. NA64 is a fixed target experiment which utilizes the active beam dump. The detection of rare processes is based on the missing energy techniques. Such techniques are used for particles whose interaction with the detector is very small, so that they escape the detection and carry away some energy. A significant missing energy in the experiment means that such particles are produced. The method of the search for the A′ → invisible decay is as follows. If the A′ exists it could be produced via the kinetic mixing with bremsstrahlung photons in the reaction of high-energy elec...

  8. Imunossupressores na Dermatologia Immunosuppressive agents in Dermatology

    Directory of Open Access Journals (Sweden)

    Aline Lopes Bressan

    2010-02-01

    Full Text Available Os imunossupressores são drogas que agem na divisão celular e têm propriedades anti-inflamatórias. Sendo assim, são essencialmente prescritos na prevenção de rejeição de transplantes e no tratamento das doenças autoimunes e inflamatórias crônicas, que, na Dermatologia, têm a psoríase como maior representante. Nesta sessão serão descritas as principais drogas imunossupressoras, com orientações para seu manejo adequado.Immunosupressants are drugs that act in cell division and have anti-inflammatory effects. Therefore, they are essentially prescribed in the prevention of transplant rejection and in the treatment of autoimmune disorders and chronic inflammatory diseases, whose main example in Dermatology is psoriasis. In this work the most important immunosuppressive drugs and orientation to properly administer them are going to be described.

  9. Resonances production from the NA60 experiment

    Directory of Open Access Journals (Sweden)

    De Falco A.

    2012-11-01

    Full Text Available The NA60 experiment at the CERN SPS has studied light vector meson production in In-In collisions at 158A GeV. The ϕ meson was detected via both the K+K− and the μ+μ− decay channels. The yields and inverse slope parameters of the mT spectra observed in the two channels are compatible within errors, different from the large discrepancies seen in Pb-Pb collisions between the hadronic (NA49 and dimuon (NA50 decay channels. In the invariant mass region 0.2 1 GeV, the excess is found to be prompt, with remarkable differences with respect to the Drell-Yan process. The Teff slope parameter, extracted from the transverse mass spectra, shows a rise with mass up to the ρ, followed by a sudden decline for higher masses. The former is consistent with radial flow of a hadronic source, while the latter suggests a dominantly partonic emission source.

  10. Envolvimento do sistema nervoso central na cisticercose

    Directory of Open Access Journals (Sweden)

    Aristides Cheto de Queiroz

    1979-03-01

    Full Text Available No estudo do envolvimento do SNC na cisticercose, verificou-se uma freqüência de 0,3%, sempre como achado incidental no estudo de rotina de autópsias; apenas um caso mostrou boa correlação com a presença de manifestações neurológicas. Esta freqüência que é baixa em relação ao que é observado em outras regiões do Brasil, mostra que a neurocisticercose não representa um grande problema na região. As reações do hospedeiro ao embrião do cisticerco foram sempre do tipo inflamatório crônico e fibrosante. Neste estudo ficou demonstrada a importância do método de impregnação pela prata (Grocott na identificação do esqueleto do cisticerco no interior de lesões fibrosantes e/ou calcificadas.

  11. Growth mechanism of NaClO 3 and NaBrO 3 crystals from aqueous ...

    Indian Academy of Sciences (India)

    A study of growth rates of NaClO3 and NaBrO3 has been carried out using a small growth cell by in situ observation. Normal growth rates of {100} faces of NaClO3 and {111} faces of NaBrO3 along ⟨ 110 ⟩ direction are measured under relatively high supersaturation ranging from 3–8%. In the initial stages of growth, {100}, ...

  12. Growth mechanism of NaClO3 and NaBrO3 crystals from aqueous ...

    Indian Academy of Sciences (India)

    A study of growth rates of NaClO3 and NaBrO3 has been carried out using a small growth cell by in situ observation. Normal growth rates of {100} faces of NaClO3 and {111} faces of NaBrO3 along ⟨ 110 ⟩ direction are measured under relatively high supersaturation ranging from 3–8%. In the initial stages of growth, {100}, ...

  13. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps.

    Science.gov (United States)

    Vedovato, Natascia; Gadsby, David C

    2014-04-01

    A single Na(+)/K(+)-ATPase pumps three Na(+) outwards and two K(+) inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na(+) than K(+) generates outward current across the cell membrane. Less well understood is the ability of Na(+)/K(+) pumps to generate an inward current of protons. Originally noted in pumps deprived of external K(+) and Na(+) ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K(+) and Na(+) concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na(+) release from phosphorylated Na(+)/K(+) pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na(+)/K(+) pumps that enables proton import is not required for completion of the 3 Na(+)/2 K(+) transport cycle. However, the back-step occurs readily during Na(+)/K(+) transport when external K(+) ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na(+)-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na(+) and K(+) ions that passes through binding site II. The inferred occurrence of Na(+)/K(+) exchange and H(+) import during the same conformational cycle of a single molecule identifies the Na(+)/K(+) pump as a hybrid transporter. Whether Na(+)/K(+) pump-mediated proton inflow may have any physiological or

  14. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps

    Science.gov (United States)

    Vedovato, Natascia

    2014-01-01

    A single Na+/K+-ATPase pumps three Na+ outwards and two K+ inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na+ than K+ generates outward current across the cell membrane. Less well understood is the ability of Na+/K+ pumps to generate an inward current of protons. Originally noted in pumps deprived of external K+ and Na+ ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K+ and Na+ concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na+ release from phosphorylated Na+/K+ pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na+/K+ pumps that enables proton import is not required for completion of the 3 Na+/2 K+ transport cycle. However, the back-step occurs readily during Na+/K+ transport when external K+ ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na+-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na+ and K+ ions that passes through binding site II. The inferred occurrence of Na+/K+ exchange and H+ import during the same conformational cycle of a single molecule identifies the Na+/K+ pump as a hybrid transporter. Whether Na+/K+ pump–mediated proton inflow may have any physiological or pathophysiological significance remains to be clarified. PMID

  15. VISIBILIDADE GAY NA ESCOLA: ESTUDANTES QUEER

    Directory of Open Access Journals (Sweden)

    Aline Ferraz da Silva

    2008-03-01

    Full Text Available Nesse artigo apresento as considerações e análises presentes na pesquisa em processo, que realizo numa escola pública. Sua constituição deve seu primeiro movimento às manifestações de desconforto e homofobia com relação a um grupo específico de três estudantes gays na comunidade escolar na qual atuo como professora. Percebo que a presença desse grupo desacomoda o cotidiano escolar e desenvolvo minha argumentação com base no potencial desestabilizador desses sujeitos, na intenção de pensar o impensável no currículo escolar. Esse trabalho parte da visibilidade de uma identidade sexual que foge à norma heterossexual e desafia a tendência normalizadora e homogeneizadora da educação. A maneira como esse grupo gay se posiciona e constrói seus corpos cruza as fronteiras do masculino/feminino, desnaturalizando as identidades sexuais e de gênero que se baseiam em características biológicas e se apresentando como diferença que escapa às classificações binárias. Na construção da pesquisa utilizo como referência o pensamento de Michel Foucault, especialmente com relação à construção histórica e discursiva de conceitos como sexualidade, identidade, diferença e normalidade que têm servido para criação e manutenção de padrões de conduta. Ao levar a problematização desses conceitos para o contexto escolar, considero produtiva a teorização queer para pensar a possibilidade de uma educação não heteronormativa, produtora de diferenças, que desconstrua identidades ao invés de tentar cristalizá-las.

  16. Response of saliva Na/K ratio to changing Na supply of lactating cows under tropical conditions

    NARCIS (Netherlands)

    Thiangtum, Wandee; Schonewille, J Thomas; Verstegen, Martin Wa; Arsawakulsudhi, Supot; Rukkwamsuk, Theera; Hendriks, Wouter H

    BACKGROUND: Factorial determination of the sodium (Na) requirement of heat-stressed lactating cows is hindered by accurate estimates of the Na losses through sweat. Direct studies, therefore, may be needed requiring information on the time course of healthy animals to become Na depleted and the

  17. Response of saliva Na/K ratio to changing Na supply of lactating cows under tropical conditions

    NARCIS (Netherlands)

    Thiangtum, Wandee; Schonewille, Thomas J.; Verstegen, Martin W.A.; Arsawakulsudhi, Supot; Rukkwamsuk, Theera; Hendriks, Wouter H.

    2017-01-01

    BACKGROUND: Factorial determination of the sodium (Na) requirement of heat-stressed lactating cows is hindered by accurate estimates of the Na losses through sweat. Direct studies, therefore, may be needed requiring information on the time course of healthy animals to become Na depleted and the

  18. Polarization and collision velocity dependence of associative ionization in cold Na (3p)-Na(3p) collisions

    NARCIS (Netherlands)

    Meijer, H.A.J.

    1990-01-01

    We studied the polarization dependence of the associative ionization (AI) process Na(3p) + Na(3p) → Na2+ at collision velocities between 100 and 700 m/s (5 and 200 K), using linearly and circularly polarized light for the excitation. We found that the polarization dependence varies strongly in the

  19. Irreversible block of cardiac mutant Na+ channels by batrachotoxin.

    Science.gov (United States)

    Wang, Sho-Ya; Tikhonov, Denis B; Mitchell, Jane; Zhorov, Boris S; Wang, Ging Kuo

    2007-01-01

    Batrachotoxin (BTX) not only keeps the voltage-gated Na(+) channel open persistently but also reduces its single-channel conductance. Although a BTX receptor has been delimited within the inner cavity of Na(+) channels, how Na(+) ions flow through the BTX-bound permeation pathway remains unclear. In this report we tested a hypothesis that Na(+) ions traverse a narrow gap between bound BTX and residue N927 at D2S6 of cardiac hNa(v)1.5 Na(+) channels. We found that BTX at 5 microM indeed elicited a strong block of hNa(v)1.5-N927K currents (approximately 70%) after 1000 repetitive pulses (+50 mV/20 ms at 2 Hz) without any effects on Na(+) channel gating. Once occurred, this unique use-dependent block of hNa(v)1.5-N927K Na(+) channels recovered little at holding potential (-140 mV), demonstrating that BTX block is irreversible under our experimental conditions. Such an irreversible effect likewise developed in fast inactivation-deficient hNa(v)1.5-N927K Na(+) channels albeit with a faster on-rate; approximately 90% of peak Na(+) currents were abolished by BTX after 200 repetitive pulses (+50 mV/20 ms). This use-dependent block of fast inactivation-deficient hNa(v)1.5-N927K Na(+) channels by BTX was duration dependent. The longer the pulse duration the larger the block developed. Among N927K/W/R/H/D/S/Q/G/E substitutions in fast inactivation-deficient hNa(v)1.5 Na(+) channels, only N927K/R Na(+) currents were highly sensitive to BTX block. We conclude that (a) BTX binds within the inner cavity and partly occludes the permeation pathway and (b) residue hNa(v)1.5-N927 is critical for ion permeation between bound BTX and D2S6, probably because the side-chain of N927 helps coordinate permeating Na(+) ions.

  20. MOBILNO POSLOVANJE NA PRIMERU UPORABE MICROSOFT DYNAMICS CRM

    OpenAIRE

    Duh, Tamara

    2016-01-01

    Hitro razvijajoči se svet nas spodbuja k hitremu reagiranju na novosti, ki se pojavljajo na trgu. Prav zaradi tega je danes zelo pomembno upravljati z mobilnimi napravami, da se lahko hitro in brez težav soočimo z morebitnimi težavami oz. zagatami. Prav iz tega razloga je mobilno poslovanje ena izmed inovativnih rešitev, ki ljudem omogoča seznanjenost z informacijami na vsakem koraku in omogoča hiter odziv na spremembe. Prav ta rešitev omogoča podjetjem, da so konkurenčna in hkrati lahko hitr...

  1. Na+ channel function, regulation, structure, trafficking and sequestration

    Science.gov (United States)

    Chen-Izu, Ye; Shaw, Robin M; Pitt, Geoffrey S; Yarov-Yarovoy, Vladimir; Sack, Jon T; Abriel, Hugues; Aldrich, Richard W; Belardinelli, Luiz; Cannell, Mark B; Catterall, William A; Chazin, Walter J; Chiamvimonvat, Nipavan; Deschenes, Isabelle; Grandi, Eleonora; Hund, Thomas J; Izu, Leighton T; Maier, Lars S; Maltsev, Victor A; Marionneau, Celine; Mohler, Peter J; Rajamani, Sridharan; Rasmusson, Randall L; Sobie, Eric A; Clancy, Colleen E; Bers, Donald M

    2015-01-01

    This paper is the second of a series of three reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on Na+ channel function and regulation, Na+ channel structure and function, and Na+ channel trafficking, sequestration and complexing. PMID:25772290

  2. Usando a antimatéria na medicina moderna

    OpenAIRE

    Machado,A.C.B.; Pleitez,V.; Tijero,M.C.

    2006-01-01

    Neste artigo, fazemos uma breve exposição de como um dos conceitos fundamentais da física moderna, a existência de antimatéria, tem aplicação na medicina, na chamada tomografia por emissão de pósitrons (PET na sigla em inglês). Ela consiste na produção de imagens tomográficas digitais do organismo que são obtidas pela detecção da radiação produzida na aniquilação do pósitron com o elétron.

  3. Novel regulation of cardiac Na pump via phospholemman.

    Science.gov (United States)

    Pavlovic, Davor; Fuller, William; Shattock, Michael J

    2013-08-01

    As the only quantitatively significant Na efflux pathway from cardiac cells, the Na/K ATPase (Na pump) is the primary regulator of intracellular Na. The transmembrane Na gradient it establishes is essential for normal electrical excitability, numerous coupled-transport processes and, as the driving force for Na/Ca exchange, thus setting cardiac Ca load and contractility. As Na influx varies with electrical excitation, heart rate and pathology, the dynamic regulation of Na efflux is essential. It is now widely recognized that phospholemman, a 72 amino acid accessory protein which forms part of the Na pump complex, is the key nexus linking cellular signaling to pump regulation. Phospholemman is the target of a variety of post-translational modifications (including phosphorylation, palmitoylation and glutathionation) and these can dynamically alter the activity of the Na pump. This review summarizes our current understanding of the multiple regulatory mechanisms that converge on phospholemman and govern NA pump activity in the heart. The corrected Fig. 4 is reproduced below. The publisher would like to apologize for any inconvenience caused. [corrected]. Copyright © 2013. Published by Elsevier Ltd.

  4. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    International Nuclear Information System (INIS)

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-01-01

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO 2 and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 deg. C for 2-6 h by changing the SiO 2 /Al 2 O 3 , H 2 O/Na 2 O and Na 2 O/SiO 2 molar ratios of precursors in the two-step process. The surface area and NH 4 + -cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m 2 /g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m 2 /g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of ∼3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously. - Graphical Abstract: Novel Na-X zeolite/porous carbon composite.

  5. Synthesis of zeolites Na-A and Na-X from tablet compressed and calcinated coal fly ash

    Science.gov (United States)

    Hu, Tao; Gao, Wenyan; Liu, Xin; Zhang, Yifu; Meng, Changgong

    2017-10-01

    Zeolites Na-A and Na-X are important synthetic zeolites widely used for separation and adsorption in industry. It is of great significance to develop energy-efficient routines that can synthesize zeolites Na-A and Na-X from low-cost raw materials. Coal fly ash (CFA) is the major residue from the combustion of coal and biomass containing more than 85% SiO2 and Al2O3, which can readily replace the conventionally used sodium silicate and aluminate for zeolite synthesis. We used Na2CO3 to replace the expensive NaOH used for the calcination of CFA and showed that tablet compression can enhance the contact with Na2CO3 for the activation of CFA through calcination for the synthesis of zeolites Na-A and Na-X under mild conditions. We optimized the control variables for zeolite synthesis and showed that phase-pure zeolite Na-A can be synthesized with CFA at reactant molar ratio, hydrothermal reaction temperature and reaction time of 1.3Na2O: 0.6Al2O3: 1SiO2: 38H2O at 80°C for 6 h, respectively, while phase-pure zeolite Na-X can be synthesized at 2.2Na2O: 0.2Al2O3: 1SiO2: 88H2O at 100°C for 8 h, respectively. The composition, morphology, specific surface area, vibration spectrum and thermogravimetry of synthesized Na-A and Na-X were further characterized.

  6. Identidade, nação e território na escrita dos intelectuais Mapuches

    Directory of Open Access Journals (Sweden)

    Claudia Zapata Silva

    2007-12-01

    Full Text Available Este artigo tem por objetivo dar conta de um novo sujeito indígena, surgido na segunda metade do século XX: o intelectual indígena contemporâneo, formado em instituições de educação superior e que constrói discursos e representações a partir de uma disciplina do conhecimento (História, Sociologia, Literatura, Antropologia, entre outras. Abordarse- á o caso particular dos intelectuais mapuches na década de noventa, a partir de uma perspectiva de análise que os considera como autores e como atores de contornos próprios no interior do que, na atualidade, se conhece como Movimento Mapuche.

  7. Erythrocyte Na+/K+ ATPase activity measured with sup 23 Na NMR

    Energy Technology Data Exchange (ETDEWEB)

    Ouwerkerk, R.; van Echteld, C.J.; Staal, G.E.; Rijksen, G. (University Hospital, Utrecht (Netherland))

    1989-11-01

    A {sup 23}Na NMR assay for measurement of erythrocyte Na+/K+ ATPase activity is presented. Using the nonpermeant shift reagent dysprosium tripolyphosphate the signals of intra- and extracellular sodium are separated, enabling measurement of sodium fluxes nondestructively, without the need to physically separate the cells from their environment. By increasing membrane permeability with nystatin we have shown that the assay allows the detection of differences in membrane permeability. With low doses of nystatin the ouabain-sensitive sodium flux increased more than twofold. With high doses of nystatin the Na+/K+ pump could not prevent an almost total equilibration of intra- and extracellular sodium. All sodium that entered the cells remained NMR visible, proving that sodium influx can be measured quantitatively. {sup 31}P NMR spectra taken before and after the assay revealed a slight acidification of the cells and no significant change in ATP concentration. No evidence of Dy3+ entering the cell was observed.

  8. Benefícios da cafeína na terapêutica

    OpenAIRE

    Ribeiro, Célia Pereira

    2013-01-01

    Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz A cafeína é uma substância amplamente consumida, principalmente pelas suas propriedades estimulantes. Mas é também utilizada a nível terapêutico, e são cada vez mais os estudos que procuram aprofundar e conhecer novas aplicações terapêuticas da cafeína. Existe uma extensa literatura acerca do citrato de cafeína para o tratamento da apneia de recém-nascidos prematuros, e os estudos indicam q...

  9. Na+-K+ pump in chronic renal failure

    International Nuclear Information System (INIS)

    Deepak, K.; Kahn, T.

    1987-01-01

    This review summarizes the evidence for the defect in Na + -K + pump in chronic renal failure, considers the role of various factors in causing this defect, and discusses the clinical implications thereof. Intracellular Na is elevated in erythrocytes, leukocytes, and muscle cells from some patients with chronic renal failure (CRF). Recent evidence suggest that this elevation of cell Na may be, in large part, a consequence of decreased number of Na + -K + pump units per cell. Maintenance dialysis over a period of weeks ameliorates the defect in intracellular Na + , and this improvement is contemporaneous with an increase in the number of Na + -K + pump sites per cell. In erythrocytes with normal cell Na + , acute hemodialysis increases the rate of 22 Na + and 42 K + transport. Many factors such as the presence of retained toxic metabolite or circulating inhibitor in the uremic plasma, or biochemical changes produced by acute hemodialysis, may explain this finding. In cells with high cell Na + , the pump-mediated 42 K + transport is normalized at the expense of a raised cell Na + . The decreased muscle membrane potential in uremic subjects has been attributed to a decreased activity of Na + -K + pump. The authors discuss the role of hormonal abnormalities and circulating inhibitors, which may cause an acute inhibition of the pump and of other factors such as K + depletion, which may cause more chronic alterations. The implications of alteration of Na + and K + pump transport and raised cell Na + on other non-pump-mediated transport pathways are discussed. Raised cell Na + may be a marker for the adequacy of maintenance dialysis in patients with end-stage renal failure

  10. Study of π0 Dalitz decays in the NA62 and NA48/2 experiments

    Science.gov (United States)

    Maurice, E.; Ambrosino, F.; Antonelli, A.; Anzivino, G.; Arcidiacono, R.; Baldini, W.; Balev, S.; Bifani, S.; Biino, C.; Bizzeti, A.; Bloch-Devaux, B.; Bolotov, V.; Bucci, F.; Ceccucci, A.; Cenci, P.; Cerri, C.; Collazuol, G.; Costantini, F.; Cotta Ramusino, A.; Coward, D.; D'Agostini, G.; Dalpiaz, P.; Danielsson, H.; Dellacasa, G.; Di Filippo, D.; DiLella, L.; Doble, N.; Duk, V.; Engelfried, J.; Eppard, K.; Falaleev, V.; Fantechi, R.; Fiorini, M.; Frabetti, P. L.; Fucci, A.; Gallorini, S.; Gatignon, L.; Gersabeck, E.; Gianoli, A.; Giudici, S.; Goudzovski, E.; Goy Lopez, S.; Gushchin, E.; Hallgren, B.; Hita-Hochgesand, M.; Iacopini, E.; Imbergamo, E.; Kekelidze, V.; Kleinknecht, K.; Kozhuharov, V.; Kurshetsov, V.; Lamanna, G.; Lazzeroni, C.; Lenti, M.; Leonardi, E.; Litov, L.; Madigozhin, D.; Maier, A.; Mannelli, I.; Marchetto, F.; Massarotti, P.; Misheva, M.; Molokanova, N.; Moulson, M.; Movchan, S.; Napolitano, M.; Norton, A.; Numao, T.; Obraztsov, V.; Palladino, V.; Pepe, M.; Peters, A.; Petrucci, F.; Peyaud, B.; Piandani, R.; Piccini, M.; Pierazzini, G.; Popov, I.; Potrebenikov, Yu.; Raggi, M.; Renk, B.; Retière, F.; Riedler, P.; Romano, A.; Rubin, P.; Ruggiero, G.; Salamon, A.; Saracino, G.; Savrié, M.; Semenov, V.; Sergi, A.; Serra, M.; Shkarovskiy, S.; Sozzi, M.; Spadaro, T.; Valente, P.; Veltri, M.; Venditti, S.; Wahl, H.; Wanke, R.; Winhart, A.; Winston, R.; Yushchenko, O.; Zinchenko, A.; NA62 Collaboration; NA48/2 Collaboration

    2017-01-01

    The NA62 experiment at CERN collected a large sample of charged kaon decays with a highly efficient trigger for decays into electrons in 2007. The kaon beam represents a source of tagged neutral pion decays in vacuum. A measurement of the electromagnetic transition form factor slope of the neutral pion in the time-like region from ∼1 million fully reconstructed π0 Dalitz decay is presented. The limits on dark photon production in π0 decays from the earlier kaon experiment at CERN, NA48/2, are also reported.

  11. Fitoterápicos na odontologia: estudo etnobotânico na cidade de Manaus

    Directory of Open Access Journals (Sweden)

    S. S. Evangelista

    2013-01-01

    Full Text Available O reconhecimento oficial da fitoterapia na odontologia no Brasil veio acompanhado de diversas lacunas na pesquisa científica e na utilização de plantas medicinais, especificamente para espécies vegetais com aplicação nas doenças da cavidade oral. O estado do Amazonas, especificamente a cidade de Manaus, não possui um diagnóstico da aplicabilidade de plantas medicinais nos serviços de atenção Odontológica. Esse estudo propôs realizar um estudo do tipo quali-quantitativo, descritivo e exploratório visando o levantamento da comercialização de plantas medicinais e o estudo etnobotânico para identificação das principais plantas medicinais indicadas e utilizadas nas patologias orais nos atendimentos odontológicos ambulatoriais na cidade de Manaus. Foram entrevistados 197 usuários do serviço odontológico, 150 Cirurgiões-Dentistas, e 47 comerciantes credenciados na prefeitura Municipal de Manaus. A amostragem foi realizada por acessibilidade ou conveniência para os Cirurgiões-Dentistas, enquanto os usuários foram selecionados através de amostragem aleatória simples, e os comerciantes de plantas medicinais foram entrevistados em sua totalidade. Os resultados demonstraram a existência de comercialização de plantas medicinais para patologias orais, destacando-se as seguintes espécies: Pedra ume cãa (Aulomyrcia sphareocarpa, Crajiru (Arrabidae chica, além da planta, sem identificação botânica, conhecida popularmente como Sara tudo. Entre os Cirurgiões-Dentistas e entre os pacientes, apenas 8% e 7,61%, respectivamente, utilizaram plantas medicinais para alterações patológicas orais. Os autores concluíram que as plantas medicinais comercializadas na cidade de Manaus são utilizadas de maneira empírica e que, apesar da Política Nacional de Práticas Integrativas e Complementares (PNPIC, novas políticas públicas de saúde devem inserir plantas medicinais e fitoterápicos de uso oral na rede pública de saúde na

  12. OGLAŠEVANJE NA SOCIALNEM OMREŽJU FACEBOOK, NA PRIMERU SPLETICNA.SI

    OpenAIRE

    Reisman, Nina

    2011-01-01

    Internet je od svojega razvoja dolgo časa obstajal kot prostor za enostransko komunikacijo. Isto se je dogajalo na televiziji, radiu in časopisih, kjer je javnost sprejemala informacije, ki jih je nekdo pripravil. Tradicionalni mediji so hitro doumeli, da takšna vrsta komunikacije ni naravna in ne predstavlja najboljšega ohranjanja gledalcev in poslušalcev. Začela se je uporabljati dvosmerna komunikacija. Trenutno v svetu najbolje poznan primer dvosmerne komunikacije je socialno omrežje F...

  13. Načrtovanje izkoriščanja hidroenergije na primeru reke Mure

    OpenAIRE

    Madjar, Klaudija

    2016-01-01

    Reka Mura lahko kot neizkoriščen hidro potencial pripomore k zvišanju deleža energije iz obnovljivih virov. V diplomski nalogi je opisano izkoriščanje energije vode za pridobivanje električne energije, predstavljene pa so tudi obstoječe hidroelektrarne v Sloveniji. Nadalje so opisane hidrološke značilnosti reke Mure in ekosistemi ob njej. Načrtovane hidroelektrarne na reki Muri predstavljajo precejšen poseg v določeno območje, zato ga je pred realizacijo potrebno dobro proučiti. Izgradnja hid...

  14. Transtorno afetivo bipolar na infância e na adolescência

    OpenAIRE

    Fu-I,Lee

    2004-01-01

    Os conhecimentos sobre transtorno afetivo bipolar com início na infância e na adolescência têm avançado muito nos últimos 15 anos. Atualmente, os esforços estão dirigidos para investigar o quadro clínico, para o desenvolvimento de instrumentos que auxiliam diagnóstico precoce e investigações de melhores formas de tratamentos de crianças e adolescentes portadores do transtorno. O presente texto tem objetivo de apresentar as principais características clínicas do transtorno em crianças e adoles...

  15. NaI(Tl) response functions

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Ortiz R, J. M. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico); Benites R, J. L. [Centro Estatal de Cancerologia de Nayarit, Calz. de la Cruz 118 Sur, Tepic, Nayarit (Mexico); De Leon M, H. A., E-mail: fermineutron@yahoo.com.mx [Instituto Tecnologico de Aguascalientes, Av. Adolfo Lopez Mateos 1801 Ote., 20155 Aguascalientes, Ags. (Mexico)

    2015-09-15

    The response functions of a NaI(Tl) detector have been estimated using Monte Carlo methods. Response functions were calculated for monoenergetic photon sources (0.05 to 3 MeV). Responses were calculated for point-like sources and for sources distributed in Portland cement cylinders. The responses were used to calculate the efficiency functions in term of photon energy. Commonly, sources used for calibration are point-like, and eventually sources to be measured have different features. In order to use the calibrated sources corrections due to solid angle, self-absorption and scattering, must be carried out. However, some of these corrections are not easy to perform. In this work, the calculated responses were used to estimate the detector efficiency of point-like sources, and sources distributed in Portland type cement. Samples of Portland paste were prepared and were exposed to photoneutrons produced by a 15 MV linac. Some of the elements in the cement were activated producing γ-emitting radionuclides that were measured with a NaI(Tl) gamma-ray spectrometer, that was calibrated with point-like sources. In order to determine the specific activity in the induced radioisotopes calculated efficiencies were used to make corrections due to the differences between the solid angle, photon absorption and photon scattering in the point-like calibration sources and the sources distributed in cement. During the interaction between photoneutrons and the cement samples three radioisotopes were induced: {sup 56}Mn, {sup 24}Na, and {sup 28}Al. (Author)

  16. Linguagens na TV Languages on tv

    Directory of Open Access Journals (Sweden)

    Glaucia Guimarães

    2008-06-01

    Full Text Available Este artigo aborda questões relativas às estratégias discursivas utilizadas na produção dos textos televisivos. Com base na Análise Crítica de Discurso (ACD, nos termos em que é formulada por Norman Fairclough, o trabalho analisa os modos pelos quais as linguagens (incluindo materiais semióticos diversos são articuladas na/pela TV, sistematiza as relações entre a articulação de linguagens e a produção de efeitos de sentido, bem como os modos de sua inscrição nas tendências discursivas contemporâneas, a saber: democratização, tecnologização e comodificação. A partir das relações entre as práticas de linguagem e as tendências destacadas, o artigo tece considerações sobre as condições de produção de leituras críticas dos textos multimidiáticos, nas suas múltiplas dimensões: dos contextos e mecanismos da produção textual à pluralidade constitutiva de sua recepção.This paper deals with issues related to discursive strategies in the production of TV texts. Based on Critical Discourse Analysis (CDA, as formulated by Norman Fairclough, it analyzes the ways languages (including several semiotic materials are articulated in order to produce a range of wanted meaning effects, as well as the ways they are inscribed in the contemporary discursive trends discussed by the author, namely: democratization, technologization and commodification. Departing from the analysis of language practices and the discursive trends underlined, the paper aims at clarifying the multiple dimensions of multimedia conditions of production, focusing on both the context and the mechanisms and the diverse reception (reading possibilities.

  17. Na(+),K (+)-ATPase as a docking station: protein-protein complexes of the Na(+),K (+)-ATPase.

    Science.gov (United States)

    Reinhard, Linda; Tidow, Henning; Clausen, Michael J; Nissen, Poul

    2013-01-01

    The Na(+),K(+)-ATPase, or sodium pump, is well known for its role in ion transport across the plasma membrane of animal cells. It carries out the transport of Na(+) ions out of the cell and of K(+) ions into the cell and thus maintains electrolyte and fluid balance. In addition to the fundamental ion-pumping function of the Na(+),K(+)-ATPase, recent work has suggested additional roles for Na(+),K(+)-ATPase in signal transduction and biomembrane structure. Several signaling pathways have been found to involve Na(+),K(+)-ATPase, which serves as a docking station for a fast-growing number of protein interaction partners. In this review, we focus on Na(+),K(+)-ATPase as a signal transducer, but also briefly discuss other Na(+),K(+)-ATPase protein-protein interactions, providing a comprehensive overview of the diverse signaling functions ascribed to this well-known enzyme.

  18. Importance of Residues Outside the Cation Binding Pocket for Na+ and K+ Binding to the Na+/K+-ATPase

    DEFF Research Database (Denmark)

    Christiansen, Line; Toustrup-Jensen, Mads Schak; Einholm, Anja P.

    Mutagenesis studies have identified several oxygen-containing residues in the transmembrane region which are important for the coordination of Na+ and/or K+. These were later confirmed by the high-resolution crystal structures of the Na+/K+-ATPase with bound Na+ or K+. However, more information...... is needed to reveal the translocation pathway through the Na+/K+-ATPase. Mutagenesis studies have shown that several other transmembrane residues located outside the cation binding pocket, including Phe785 and Phe788, affect the ion binding properties of the Na+/K+-ATPase (1,2). It is well...... not significantly affect the Na+ binding properties of the Na+/K+-ATPase. 1. Vilsen, B. (1999) Biochemistry 38, 11389 2. Rodacker, V. et al (2006) JBC 281, 18539 3. Laursen M et al. (2013) PNAS 110, 10958...

  19. Effect of growth in lithium on ouabain binding, Na-K-ATPase and Na and K transport in hela cells.

    Science.gov (United States)

    Boardman, L J; Hume, S P; Lamb, J F; Polson, J

    1975-01-01

    1. HeLa cells were grown for 24 hr in growth medium in which part of the Na was replaced with Li. Ion contents, cell volumes and numbers, Na-K-ATPase and specific ouabain binding were measured. In some experiments the Na efflux and net Na transport was also measured. 2. Growth in Li caused a rise in the specific ouabain binding and membrane Na-K-ATPase of these cells. The Li concentrations in the cells necessary to produce this effect ranged up to 50 mM. 3. It is suggested that Li, like Na, acts on the genetic material of the cells to cause the production of more Na pumps within the membrane. PMID:124350

  20. The NA48 liquid krypton prototype calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Barr, G.D.; Buchholz, P.; Carosi, R.; Coward, D.; Cundy, D.; Doble, N.; Gatignon, L.; Gonidec, A.; Hallgren, B.; Kesseler, G.; Lacourt, A.; Laverriere, G.; Linser, G.; Mast, M.; Schilly, P.; Schinzel, D.; Seidl, W.; Taureg, H.; Wahl, H.; Wicht, P. (CERN, Geneva (Switzerland)); Bertanza, L.; Bigi, A.; Calafiura, P.; Casali, R.; Cerri, C.; Fantechi, R.; Gennaro, G.; Gorini, B.; Mannelli, I.; Marzulli, V.; Pierazzini, G.; Schiuma, D.; Sergiampietri, F. (INFN, Pisa (Italy) Scuola Normale, Pisa (Italy) Univ. Pisa (Italy)); Bederede, D.; Debeer, M.; Debu, P.; Peyaud, B. (CE-Saclay-DAPNIA, 91 - Gif-sur-Yvette (France)); Kreutz, A. (Univ. Gesamthochschule Siegen (Germany)); Griesmayer, E.; Markytan, M.; Neuhofer, G.; Pernicka, M.; Taurok, A.; Viehhauser, G.; Wulz, C.E. (Oesterreichische Akademie der Wissenschaften, Inst. fuer Hochenergiephysik, Vienna (Austria)); Cagliari-Cambridge-CERN-Dubna-Edingburgh-Ferrara-Mainz-Perugia-Pisa-Saclay-Siegen-Torino-Vienna Collaboration

    1992-12-01

    The NA48 experiment for a precision measurement of the CP violation parameter element of'/element of in K[sup 0][yields]2[pi] decays will require a fast electromagnetic calorimeter with excellent energy and time resolution. A quasi homogeneous calorimeter using liquid krypton and a fast readout with 40 MHz FADCs is proposed. A prototype with 400 kg of liquid krypton was built and tested in an electron beam. Results for the energy, space and time resolution of this prototype are given. (orig.).

  1. Holistična obravnava motenj hranjenja

    OpenAIRE

    Arzenšek, Pia

    2017-01-01

    Izhodišča: Stres, nepravičnost, nespoštljivost, mediji, kot socialni, ter biološko-genetski, družinski in psihološki dejavniki tveganja v kombinacijah vplivajo na razvoj različnih motenj, bolezni, tudi motenj hranjenja (MH). Najpogostejše med njimi so anorexia nervosa, bulimija nervosa in kompulzivno prenajedanje, kot duševne motnje po mednarodni klasifikaciji. V novejšem času se pojavljajo nove oblike MH (ortoreksija, bigoreksija…). O MH govorimo kadar hrana postane osrednja tema posamezniko...

  2. O estresse na atividade gerencial do enfermeiro

    OpenAIRE

    Lautert Liana; Chaves Enaura H. B.; Moura Gisela M. S. S. de

    1999-01-01

    O trabalho do enfermeiro, principalmente no âmbito hospitalar, está, conforme diversos estudos, entre os que mais geram estresse em seus profissionais. Dessa forma, o objetivo desta investigação foi identificar as fontes geradoras de estresse na atividade gerencial do enfermeiro que trabalha no hospital e as principais alterações que o estresse pode acarretar sobre a saúde desse profissional. Trata-se de uma pesquisa quantitativa com uma amostra de 207 enfermeiros, realizada em 1996 em um hos...

  3. Results on leptonic probes from NA50

    CERN Document Server

    Alessandro, B; Arnaldi, R; Atayan, M; Baglin, C; Baldit, A; Bedjidian, Marc; Beolè, S; Boldea, V; Bordalo, P; Borenstein, S R; Borges, G; Bussière, A; Capelli, L; Castanier, C; Castor, J I; Chaurand, B; Cheynis, B; Chiavassa, E; Cicalò, C; Claudino, T; Comets, M P; Constantinescu, S; Cortese, P; Cruz, J; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Espagnon, B; Fargeix, J; Force, P; Gallio, M; Gavrilov, Yu K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grigorian, S; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Hakobyan, R S; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Macciotta, P; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Prino, F; Puddu, G; Quintans, C; Ramello, L; Ramos, S; Rato-Mendes, P; Riccati, L; Romana, A; Santos, H; Saturnini, P; Scalas, E; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, F; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, Ermanno; Villatte, L; Willis, N; Wu, T

    2003-01-01

    The NA50 Collaboration has performed a new measurement of the J/ psi yield in Pb-Pb collisions at 158 GeV/nucleon in improved experimental conditions. Our preliminary analysis of the year 2000 data sample, while confirming the onset of anomalous suppression and the non saturation of the J/ psi /Drell-Yan cross-section ratio, shows that peripheral Pb-Pb interactions follow the normal nuclear absorption pattern, which has in turn been established more precisely thanks to high statistics p-A data. (11 refs).

  4. Processo de pintura na Preh Portugal

    OpenAIRE

    Pontes, José Luís Pereira

    2016-01-01

    Neste estágio trabalhei no departamento de Engenharia de Processo e Automatização. Os Engenheiros que trabalham nesse departamento têm diversas funções. Desde ser responsáveis por uma linha de montagem; responsável por todas as alterações de engenharia; responsável pela parte eletrónica; responsável pela parte de pintura; entre outras. Também auxiliei na criação e atualização de Standards dentro da organização. Inicialmente, estes Standards ou estavam em formato Excel com basta...

  5. Cerenkov counter for the experiment NA3

    CERN Multimedia

    1978-01-01

    The program of the NA3 experiment included the study of hadronic interactions with a large transverse momentum pT, thus the inclusion in the set-up of three gas threshold Cerenkov counters of large acceptance. The photo shows the downstream part of the second Cerenkov (located at the output of the magnet). The yellow membrane is a temporary protection for the optics (shown in photo 7810540X) to be taken away when fixing this part to the gas tank (entering the magnet and not shown). The photomultipliers all around are heavily shielded.

  6. Sexualidade, Espiritualidade e Conjugalidades na Wicca Brasileira

    OpenAIRE

    Cordovil, Daniela

    2017-01-01

    Resumo Este artigo propõe uma análise do papel da sexualidade nas práticas da Wicca, religião neopagã surgida na Inglaterra entre 1940 e 1950. Atualmente, a Wicca é um movimento mundial multifacetado, que segue inúmeras vertentes. Esta pesquisa investiga concepções e práticas ligadas à sexualidade presentes entre grupos que praticam a Wicca publicamente em diversas capitais do Brasil. Esses grupos estão organizados em tradições (grupos religiosos com viés iniciático) que comandam associações ...

  7. Qualidade de vida na epilepsia infantil

    OpenAIRE

    SOUZA ELISABETE ABIB PEDROSO DE

    1999-01-01

    A epilepsia é desordem crônica que ocorre principalmente na infância e adolescência. Tradicionalmente, o tratamento da epilepsia enfatiza aspectos neurológicos mais do que fatores psicológicos. A aten��ão voltada simplesmente para o controle das crises no contexto clínico pode não ser suficiente para entender a grande amplitude de problemas que afetam a qualidade de vida das crianças com epilepsia. Muitas das dificuldades psicossociais dos adultos com epilepsia desenvolvem-se a partir de comp...

  8. DEPRESSÃO E ENVELHECIMENTO NA CONTEMPORANEIDADE

    Directory of Open Access Journals (Sweden)

    Delia Catullo Goldfarb

    2010-02-01

    Full Text Available RESUMO: O presente texto reproduz os trabalhos apresentados em mesa redonda sobre depressão e envelhecimento na contemporaneidade no III Congresso Ibero-americano de Psicogerontologia, realizado em novembro de 2010 em São Paulo. Estes trabalhos são resultado de reflexões precedentes em um grupo de estudos e de discussão de casos clínicos composto por psicanalistas. A depressão é uma figura psicopatológica de presença maciça nos dias de hoje. Na velhice o acúmulo de perdas e a aproximação da morte podem produzir um estado de tristeza, fundo depressivo que caracteriza um momento de recolhimento em que ocorrem os processos de luto. Em alguns sujeitos o que se verifica é a instalação de um episódio depressivo que indica a paralisação destes processos elaborativos e a progressão de um esvaziamento do sentido para a vida, restando, neste contexto, apenas a espera pela morte. Neste trabalho serão discutidos aspectos que concernem a vivência destas duas modalidades de enfrentamento da entrada na velhice, levando-se em conta as maneiras como a cultura pode favorecer a ocorrência destes percursos distintos do envelhecer, e como ela os aloja atualmente em um movimento de desconsideração da subjetividade: desanimo da velhice ou problema neuroquímico? Serão apresentadas hipóteses para a produção da depressão como psicopatologia no envelhecimento e reflexões sobre observações clínicas que derivam destes quadros clínicos, tais como: a crise da percepção da entrada na velhice, o corpo hipocondríaco, a paralisia do tempo, a vivência do desamparo. Palavras-chave: depressão, envelhecimento, cultura, corpo, tempo

  9. O mito da autoestima na aprendizagem escolar

    OpenAIRE

    Franco, Adriana de Fátima

    2009-01-01

    Este artigo analisa, nos marcos da perspectiva sócio-histórica, a construção social da autoestima e suas relações com o fracasso escolar. Fundamentada nos pressupostos de Vigotski, nega a possibilidade da valoração que o sujeito faz de si estar atrelada a atributos naturalmente humanos e presentes desde o nascimento. A compreensão do ser humano é feita a partir de uma análise de homem enquanto ser concreto, social, histórico e cultural que constrói sua humanidade na interação com outros homen...

  10. O dano pessoal na sociedade de risco

    OpenAIRE

    Hofmeister, Maria Alice Costa

    2000-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas. Estudo do dano pessoal e sua indenização, sob a ótica do dano corporal. Equaciona-se a matéria a partir do homem na pós-modernidade. Conclui-se que urge repensar as normas à luz de uma interpretação constitucional para atender à função mais importante da responsabilidade hoje reconhecida: indenizar a vítima. A indenização deverá ser reorientada para priorizar as necessidades da vítima em concreto. ...

  11. O TRADICIONALISMO NA LINGUAGEM JURÍDICA

    OpenAIRE

    Eliane Simões Pereira Bulhões

    2009-01-01

    Este artigo tem como objetivo analisar alguns aspectos do discurso atual do Direito brasileiro. Apoiando-se em pressupostos teóricos do lingüista russo Mikhail Bakhtin (1895-1975), segundo os quais a linguagem é instância ideológica por excelência, presentes na obra Marxismo e filosofia da linguagem, procuramos avaliar a linguagem jurídica como expressão do componente ideológico. Para tanto utilizamos um modelo de petição jurídica colhido em um guia para advogados, o qual nos serve como corpu...

  12. O TRADICIONALISMO NA LINGUAGEM JURÍDICA

    Directory of Open Access Journals (Sweden)

    Eliane Simões Pereira Bulhões

    2009-02-01

    Full Text Available Este artigo tem como objetivo analisar alguns aspectos do discurso atual do Direito brasileiro. Apoiando-se em pressupostos teóricos do lingüista russo Mikhail Bakhtin (1895-1975, segundo os quais a linguagem é instância ideológica por excelência, presentes na obra Marxismo e filosofia da linguagem, procuramos avaliar a linguagem jurídica como expressão do componente ideológico. Para tanto utilizamos um modelo de petição jurídica colhido em um guia para advogados, o qual nos serve como corpus representativo da linguagem forense.

  13. [Effects of NaCl stress on the seedling growth and K(+)- and Na(+) -allocation of four leguminous tree species].

    Science.gov (United States)

    Mo, Hai-Bo; Yin, Yun-Long; Lu, Zhi-Guo; Wei, Xiu-Jun; Xu, Jian-Hua

    2011-05-01

    Taking the pot-cultured seedlings of four leguminous tree species (Albizia julibrissin, Robinia pseudoacacia, Sophora japonica, and Gleditsia sinensis) as test materials, this paper studied their growth indices, critical salt concentration (C50), and K+ and Na+ allocation under different levels of NaCl stress, aimed to understand the difference of test tree species in salt tolerance. NaCl stress inhibited the seedling growth of the tree species. Under NaCl stress, the dry matter accumulation decreased, while the root/shoot ratio increased, especially for A. julibrissin and G. sinensis. Quadratic regression analysis showed that the C50 of A. julibrissin, R. pseudoacacia, S. japonica, and G. sinensis was 3.0 per thousand, 5.0 per thousand, 4.5 per thousand, and 3.9 per thousand, respectively, i.e., the salt tolerance of the four tree species was in the order of R. pseudoacacia > S. japonica > G. sinensis > A. julibrissin. In the root, stem, and leaf of the four tree species seedlings, the Na+ content increased with the increase of NaCl stress, while the K+ content (except in the root of A. julibrissin) decreased after an initial increase, resulting in a larger difference in the K+/Na+ ratio in the organs. Under the same NaCl stress, the allocation of Na+ in different organs of the four tree species seedlings decreased in the order of root>stem>leaf, while that of K+ differed with tree species and NaCl stress, and leaf was the main storage organ for K+. The K+/Na+ ratio in different organs decreased in the sequence of leaf>stem>root. R. pseudoacacia under NaCl stress accumulated more K+ and less Na+ in stem and leaf, and had higher K+/Na+ ratio in all organs and higher dry mass, being assessed to be more salt-tolerant. In contrast, A. julibrissin under high NaCl stress accumulated more Na+ in stem and leaf, and had a lower K+/Na+ ratio in all organs and lower dry mass, being evaluated to be lesser salt-tolerant. The K+ accumulation in seedling stem and leaf and the Na

  14. Relationship between intracellular Na+ concentration and reduced Na+ affinity in Na+,K+-ATPase mutants causing neurological disease

    DEFF Research Database (Denmark)

    Toustrup-Jensen, Mads Schak; Einholm, Anja P.; Schack, Vivien

    was observed for the +28 mutation of α2 despite a high expression level. A significant rise of [Na+]i and reduction of [K+]i was detected in cells expressing mutants with reduced Na+ affinity and did not require a concomitant reduction of the maximal catalytic turnover rate or expression level. Moreover, two...

  15. Adsorbed or intercalated: Na on graphene/Ir(111)

    Science.gov (United States)

    Pervan, Petar; Lazić, Predrag

    2017-09-01

    Interaction of sodium with graphene (Gr) on Ir(111) was studied with the aim to resolve the issue of Na adsorption/intercalation kinetics. The system Na/Gr/Ir(111) was studied by means of angle-resolved photoemission spectroscopy, low-energy electron diffraction, and ab initio density functional theory (DFT) calculation. It has been found that at room temperature (RT) and low concentrations Na is dominantly adsorbed on graphene. At higher concentrations, an intercalation process sets in so that it is possible to observe the coexistence of these two states. Eventually, all Na atoms are found in the intercalated state as determined by exposure to oxygen. While adsorption of Na on graphene already intercalated by Na [Na/Gr/Na/Ir(111) system] at RT was not possible, we could observe Li adsorption through the increase of Dirac point binding energy. Li coadsorption strongly affects the binding energy of the iridium surface state as well. This finding was supported by DFT calculations of adsorption energy of Na and Li on bare and fully Na intercalated graphene.

  16. Advancement of technology towards developing Na-ion batteries

    Science.gov (United States)

    Jamesh, Mohammed Ibrahim; Prakash, A. S.

    2018-02-01

    The Na-ion-batteries are considered much attention for the next-generation power-sources due to the high abundance of Na resources that lower the cost and become the alternative for the state of the art Li-ion batteries in future. In this review, the recently reported potential cathode and anode candidates for Na-ion-batteries are identified in-light-of-their high-performance for the development of Na-ion-full-cells. Further, the recent-progress on the Na-ion full-cells including the strategies used to improve the high cycling-performance (stable even up-to 50000 cycles), operating voltage (even ≥ 3.7 V), capacity (>350 mAhg-1 even at 1000 mAg-1 (based-on-mass-of-the-anode)), and energy density (even up-to 400 Whkg-1) are reviewed. In addition, Na-ion-batteries with the electrodes containing reduced graphene oxide, and the recent developments on symmetric Na-ion-batteries are discussed. Further, this paper identifies the promising Na-ion-batteries including the strategies used to assemble full-cell using hard-carbon-anodes, Na3V2(PO4)3 cathodes, and other-electrode-materials. Then, comparison between aqueous and non-aqueous Na-ion-batteries in terms of voltage and energy density has been given. Later, various types of electrolytes used for Na-ion-batteries including aqueous, non-aqueous, ionic-liquids and solid-state electrolytes are discussed. Finally, commercial and technological-developments on Na-ion-batteries are provided. The scientific and engineering knowledge gained on Na-ion-batteries afford conceivable development for practical application in near future.

  17. Apical Na+ permeability of frog skin during serosal Cl- replacement.

    Science.gov (United States)

    Leibowich, S; DeLong, J; Civan, M M

    1988-05-01

    Gluconate substitution for serosal Cl- reduces the transepithelial short-circuit current (Isc) and depolarizes short-circuited frog skins. These effects could result either from inhibition of basolateral K+ conductance, or from two actions to inhibit both apical Na+ permeability (PapNa) and basolateral pump activity. We have addressed this question by studying whole-and split-thickness frog skins. Intracellular Na+ concentration (CcNa) and PapNa have been monitored by measuring the current-voltage relationship for apical Na+ entry. This analysis was conducted by applying trains of voltage pulses, with pulse durations of 16 to 32 msec. Estimates of PapNa and CcNa were not detectably dependent on pulse duration over the range 16 to 80 msec. Serosal Cl- replacement uniformly depolarized short-circuited tissues. The depolarization was associated with inhibition of Isc across each split skin, but only occasionally across the whole-thickness preparations. This difference may reflect the better ionic exchange between the bulk medium and the extracellular fluid in contact with the basolateral membranes, following removal of the underlying dermis in the split-skin preparations. PapNa was either unchanged or increased, and CcNa either unchanged or reduced after the anionic replacement. These data are incompatible with the concept that serosal Cl- replacement inhibits PapNa and Na,K-pump activity. Gluconate substitution likely reduces cell volume, triggering inhibition of the basolateral K+ channels, consistent with the data and conclusions of S.A. Lewis, A.G. Butt, M.J. Bowler, J.P. Leader and A.D.C. Macknight (J. Membrane Biol. 83:119-137, 1985) for toad bladder. The resulting depolarization reduces the electrical force favoring apical Na+ entry. The volume-conductance coupling serves to conserve volume by reducing K+ solute loss. Its molecular basis remains to be identified.

  18. Estudo comparativo entre ropivacaína a 0,5% e bupivacaína a 0,5% ambas hiperbáricas, na raquianestesia

    OpenAIRE

    Carvalho, Afonso Cláudio dos Reis e; Machado, Jean Abreu; Nociti, José Roberto

    2002-01-01

    JUSTIFICATIVA E OBJETIVOS - Estudos clínicos e experimentais já demonstraram a eficácia e a segurança da ropivacaína aplicada a estruturas nervosas por via subaracnóidea. Por outro lado, a potência da ropivacaína em raquianestesia é aproximadamente igual à metade da potência de bupivacaína, considerando-se soluções hiperbáricas. O objetivo deste estudo foi comparar as características do bloqueio subaracnóideo com ropivacaína ou bupivacaína hiperbáricas, em doses equipotentes. MÉTODO - Vinte p...

  19. Saturation effects in Na lidar temperature measurements

    International Nuclear Information System (INIS)

    von der Gathen, P.

    1991-01-01

    Na atoms residing in the 80-110 km altitude region can be used to probe the Doppler-broadened hyperfine structure (hfs) of their D 2 resonance by ground-bases lidar and hence to deduce atmospheric temperatures. In principle, two different methods may be employed: (1) wavelength scanning of the hfs with a narrow-band laser and signal detection with a broad-band receiver, and (2) use of a broad-band laser and wavelength scanning of the hfs with a narrow-band receiver. These two methods are affected in different ways by laser-induced saturation in the Na layer, the effect on the measurements of sodium densities and of atmospheric temperatures being quite different. Density measurements are affected by the absolute level of saturation. Temperature measurements, however, are affected by the difference in saturation at the scanned wavelengths. If, additionally, observed signal levels are taken into account, method 1 is more efficient than method 2 for both types of measurements at nighttime, whereas a modified method 2 surpasses method 1 for temperature measurements at daytime

  20. ESTUDO DO EMPODERAMENTO NA PERSPECTIVA DAS MULHERES

    Directory of Open Access Journals (Sweden)

    Karoline Brasil de Oliveira

    2015-12-01

    Full Text Available Este trabalho objetivou conhecer como as mulheres que ocupam cargos de liderança, utilizam o empoderamento no exercício profissional em uma instituição de ensino e tecnologia em Criciúma, Santa Catarina, Brasil. Na revisão da literatura foram contextualizados a mulher e sua inserção no mercado de trabalho, em busca de uma concepção de empoderamento e as dimensões do empoderamento da mulher no mercado de trabalho. A metodologia utilizada teve caráter descritivo e qualitativo. O instrumento de coleta de dados consistiu num roteiro com 16 questões que abordaram o bem-estar e sucesso profissional, o reconhecimento familiar, o processo de ascensão profissional e a participação das mulheres nos processos decisórios organizacionais. A pesquisa foi realizada com 10 mulheres que ocupavam cargos de chefia em diferentes setores da instituição em análise. Os resultados obtidos na pesquisa revelaram que as entrevistadas já demonstram expressões de empoderamento em seus cotidianos e a mulher se apresenta mais confiante e preparada para participar das tomadas de decisões em níveis hierárquicos maiores, além de interferir no próprio meio.

  1. Desafios na gestão escolar

    Directory of Open Access Journals (Sweden)

    Flávia Obino Corrêa Werle

    2015-09-01

    Full Text Available Este estudo discute a avaliação em larga escala da educação básica, os processos de regulação e debate processos de gestão realizados no interior da escola pública. Seu objetivo é compreender como a equipe diretiva de duas escolas da rede pública estadual de Porto Alegre, Brasil, se apropria dos resultados do Indíce de Desenvolvimento da Educação Básica (IDEB e como lida com eles na gestão escolar. A metodologia utilizada é de cunho qualitativo com coleta de dados através de um questionário estruturado. Apresenta os resultados do IDEB das duas escolas no período de 2009 e 2011. Na prática escolar a apropriação ocorre em três dimensões (pedagógica, administrativa e participativa e promove diálogos em diferentes níveis: com a hierarquia do sistema educacional, com a comunidade externa à escola e, internamente, com os professores e demais membros da comunidade escolar.

  2. Criptococose pulmonar: aspectos na tomografia computadorizada

    Directory of Open Access Journals (Sweden)

    Silva Ana Carina Gamboa da

    2003-01-01

    Full Text Available A criptococose pulmonar é uma doença causada pelo Criptococcus neoformans, um fungo unimórfico que possui distribuição mundial, existindo na mesma forma tanto no seu habitat natural quanto em animais e humanos. A doença possui apresentações clínica e patológica variáveis e pode manifestar-se tanto em pacientes com a imunidade normal como em imunocomprometidos, que representam a maioria dos casos. Neste trabalho são analisados os aspectos encontrados nas tomografias computadorizadas do tórax de 14 pacientes com criptococose pulmonar confirmada. Os achados mais freqüentes na tomografia do tórax foram as massas e os nódulos pulmonares. Outros aspectos observados foram as áreas de escavação, as consolidações, o espessamento do interstício peribroncovascular e o reticulado difuso. Massa pulmonar foi o achado isolado mais comum (64,2%, seguido dos nódulos isolados ou múltiplos (35,7%. Doença pulmonar difusa foi vista em apenas 14,2% dos casos. Os lobos superiores foram os mais comprometidos, sendo a doença mais comum nas regiões anteriores. A tomografia do tórax permitiu avaliar com precisão o grau de comprometimento do parênquima pulmonar.

  3. Vinhos, Turismo e Pluriatividade na Agricultura

    Directory of Open Access Journals (Sweden)

    Hernanda Tonini

    2013-06-01

    Full Text Available A gastronomia, além de ter importante relação com a economia, é uma forma expressiva da cultura dos indivíduos, desde o tipo de alimentos cultivados até a maneira de seu preparo e consumo. O presente artigo propõe-se a analisar a relação entre o enoturismo – centralizado na existência do vinho enquanto elemento gastronômico – e o fenômeno da pluriatividade na agricultura familiar, vista nos últimos anos como alternativa positiva para sua reprodução econômica e social. O fluxo turístico em regiões vitivinícolas gera novas oportunidades de trabalho e faz com que agricultores e suas famílias dividam a mão de obra agrícola, até então direcionada ao cultivo da uva e outros alimentos para subsistência, com atividades não agrícolas – como o artesanato, o acolhimento de visitantes em pousadas, a atuação em restaurantes, entre outras – como chance de subsistência. Este panorama transforma as realidades do mundo rural, alterando a relação do agricultor com a produção de alimentos e a forma como o mesmo os utiliza, além de reestruturar o ambiente sociocultural no seu entorno.  

  4. Brasileiros na fronteira com o Paraguai

    Directory of Open Access Journals (Sweden)

    Marcia Anita Sprandel

    2006-08-01

    Full Text Available O ARTIGO apresenta uma cartografia da situação social dos brasileiros e seus descendentes que vivem no Paraguai. Os distintos mapas (artigos, dissertações, teses e relatórios, com suas múltiplas perspectivas, permitem que se relativizem as narrativas midiáticas e a concepção da região como "lugar difícil". Ao discorrer sobre trabalhos de diversos autores, de distintas áreas acadêmicas, o artigo aponta para a mportância de cada um deles na construção de uma análise que traduza a pluralidade de pontos de vista coexistentes na região e que são, muitas vezes, inconciliáveis.THE ARTICLE presents a cartography of the social situation of the Brazilians and its descendants who live in Paraguay. The distinct maps (articles, these and reports deconstruct the media’s narratives and the conception of the region as a "difficult place". Works of diverse authors, of distinct academic areas, demonstrate the importance of each one of them in the construction of an analysis that translates the plurality of points of view.

  5. A biotecnologia na agropecuária

    Directory of Open Access Journals (Sweden)

    João Lúcio de Azevedo

    1986-11-01

    Full Text Available This review reports the use of biotechnology in agriculture and animal husbandry. The main techniques and the most important products both in experimental stage or in commercial use are reported. The work intends to give a global vision to the theme, chronologically and spacely, showing the main lines of research and what has been obtained in this area. The techniques and products that are related to genetics and breeding are emphasized. Revisão Bibliográfica do emprego da biotecnologia na agropecuária, mostrando um levantamento das técnicas mais promissoras e de seus principais produtos, tanto em fase experimental como em uso comercial. Pretende-se dar uma visão global do assunto, cronológica e espacialmente, não se prendendo à detalhes, mostrando, em Unhas gerais, o que foi feito e o que se faz, atualmente, em biotecnologia. As técnicas e produtos que influenciam a área de genética e melhoramento genético na agropecuária, são enfatizadas.

  6. The NA62 GigaTracker

    Science.gov (United States)

    Aglieri Rinella, G.; Alvarez Feito, D.; Arcidiacono, R.; Biino, C.; Bonacini, S.; Ceccucci, A.; Chiozzi, S.; Gil, E. Cortina; Ramusino, A. Cotta; Degrange, J.; Fiorini, M.; Gamberini, E.; Gianoli, A.; Kaplon, J.; Kluge, A.; Mapelli, A.; Marchetto, F.; Minucci, E.; Morel, M.; Noël, J.; Noy, M.; Perktold, L.; Perrin-Terrin, M.; Petagna, P.; Petrucci, F.; Poltorak, K.; Romagnoli, G.; Ruggiero, G.; Velghe, B.; Wahl, H.

    2017-02-01

    The GigaTracker is a hybrid silicon pixel detector built for the NA62 experiment aiming at measuring the branching fraction of the ultra-rare kaon decay K+ →π+ ν ν bar at the CERN SPS. The detector has to track particles in a beam with a flux reaching 1.3 MHz/mm2 and provide single-hit timing with 200 ps RMS resolution for a total material budget of less than 0.5% X0 per station. The tracker comprises three 60.8 mm×27 mm stations installed in vacuum (∼10-6 mbar) and cooled with liquid C6F14 circulating through micro-channels etched inside a few hundred micron thick silicon plates. Each station is composed of a 200 μm thick silicon sensor read out by 2×5 custom 100 μm thick ASICs, called TDCPix. Each chip contains 40×45 asynchronous pixels, 300 μm×300 μm each and is instrumented with 100 ps bin time-to-digital converters. In order to cope with the high rate, the TDCPix is equipped with four 3.2 Gb/s serialisers sending out the data. We will describe the detector and the results from the 2014 and 2015 NA62 runs.

  7. The NA62 GigaTracker

    CERN Document Server

    Perrin-Terrin, Mathieu

    2015-01-01

    The GigaTracker is an hybrid silicon pixel detector built for the NA62 experiment aiming at measuring the branching fraction of the ultra-rare kaon decay K + ! p + n ̄ n at the CERN SPS. The detector has to track particles in a beam with a flux reaching 1.3 MHz/mm 2 and provide single-hit timing with 200ps RMS resolution for a total material budget of less than 1.5 X 0 . The tracker comprises three 60.8mm 27mm stations installed in vacuum ( 10$^{-6}$ mbar) and cooled with liquid C 6 F 14 circulating through micro-channels etched inside few hundred of microns thick silicon plates. Each station is composed of a 200 m m thick silicon sensor readout by 2 x 5 cus- tom 100 m m thick ASIC, called TDCPix. Each chip contains 40 x 45 asynchronous pixels, each 300 m m x 300 m m and is instrumented with 100ps bin time-to-digital converters. In order to cope with the high rate, the TDCPix is equipped with four 3.2Gb/s serialisers sending out the data. We will describe the detector and the results from the 2014 NA62 ru...

  8. Mercosul educativo na carreira de Enfermagem

    Directory of Open Access Journals (Sweden)

    Roseli Schmoeller

    2012-10-01

    Full Text Available O Mercosul, instituído com vistas à integração econômica, política, social e cultural entre os países membros, atualmente destaca-se pelas estratégias integrativas de âmbito educacional. Este artigo aborda os movimentos acerca da formação acadêmica dos cursos de Enfermagem e o trajeto histórico de integração educacional, apresentando o Sistema de Acreditação dos Cursos Universitários do Mercosul, o ARCU-SUL, além dos setores responsáveis por esse processo e as perspectivas para a Enfermagem nos países do Mercosul. Entendemos que para o desenvolvimento de profissionais críticos, reflexivos e com compromisso político-social, é fundamental investir na formação e na qualidade dos centros de ensino em Enfermagem.

  9. NA-CORDEX: Overview and Sample Results

    Science.gov (United States)

    Bukovsky, Melissa; Mearns, Linda; Arritt, Raymond; Castro, Christopher; Chang, Hsin-I.; Christensen, Jens; Christensen, Ole; Frigon, Anne; Gutowski, William; Kjellström, Erik; Laprise, René; McGinnis, Seth; Nikulin, Grigory; Scinocca, John; Sushama, Laxmi; Winger, Katje

    2017-04-01

    The North American CORDEX program (NA-CORDEX) has produced a good number of projections of climate according to the first phase of the CORDEX program. These simulations are based on a wide range of regional and global climate models, and some matrices of combinations have resulted. The RCMs involved include: WRF, CanRCM4, CRCM5, RegCM4, RCA4, and HirHam5. Driving GCMs include: EC-EARTH, CanESM2, HadGEM2-ES, GFDL-ESM2M, MPI-ESM-LR. These GCMs nicely span the equilibrium climate sensitivity of the GCMs making up the CMIP5 suite of models. Simulations have been performed both at .44 and .22 spatial resolutions and often for both RCP8.5 and 4.5. We will present an update of the status of NA-CORDEX, an overview of the simulations, and some of the results for North America, focusing on the quality of the baseline climate simulations and the projections of precipitation and temperature.

  10. NA-CORDEX: Overview and New Results

    Science.gov (United States)

    Mearns, L.; Arritt, R. W.; Bukovsky, M. S.; Castro, C. L.; Chang, H. I.; Christensen, J. H.; Christensen, O. B.; Gutowski, W. J., Jr.; Kjellstrom, E.; Laprise, R.; McGinnis, S. A.; Nikulin, G.; Scinocca, J. F.; Sushama, L.; Frigon, A.; Winger, K.

    2017-12-01

    The North American CORDEX program (NA-CORDEX) has produced a good number of projections of climate according to the first phase of the CORDEX program. These simulations are based on a wide range of regional and global climate models, and some matrices of combinations have resulted. The RCMs involved include: WRF, CanRCM4, CRCM5, RegCM4, RCA4, and HirHam5. Driving GCMs include: EC-EARTH, CanESM2, HadGEM2-ES, GFDL-ESM2M, MPI-ESM-LR, and MPI-ESM-MR. These GCMs nicely span the equilibrium climate sensitivity of the GCMs making up the CMIP5 suite of models. Simulations have been performed both at .44 and .22 spatial resolutions and often for both RCP8.5 and 4.5. The time period for all simulations is 1950-2100. We will present an update of the results of NA-CORDEX, an overview of the simulations, and some detailed results for North America, focusing on the quality of the baseline climate simulations and the projections of precipitation and temperature. We will particularly focus on a 2 by 3 experiment with 2 RCMs driven by 3 GCMs. We also introduce a new metric for comparison of regional model results driven by GCMs of different climate sensitivities, which is regional model climate sensitivity.

  11. Autonomia e vulnerabilidade na vida dos adolescentes

    Directory of Open Access Journals (Sweden)

    Renata R. de Oliveira

    2007-05-01

    Full Text Available Este trabalho foi realizado com a finalidade de estabelecer relações entre os princípios éticos da autonomia e vulnerabilidade e a vida de adolescentes, pessoas reconhecidamente passíveis de síndromes depressivas, uso abusivo de drogas ilícitas, alcoolismo e tabagismo. Famílias desestruturadas, pais ausentes, companhia de amigos que levam a diferentes vícios, facilidade de acesso a fontes desencontradas de informações e uma sociedade indiferente afetam o desenvolvimento normal dos jovens. Considera-se, ainda, o grande desafio apresentado a profissionais de saúde em agir na busca de reduzir a vulnerabilidade dos adolescentes e permitir que os mesmo usem de autonomia com responsabilidade na tomada de decisões em suas vidas pessoais. O cuidado com os mesmos deve ser mais integral e ativo e a sociedade ainda não reconheceu adequadamente a importância de cuidar do desenvolvimento saudável desse imenso contingente humano.

  12. ESCOLA NA OU DA PRISÃO?

    Directory of Open Access Journals (Sweden)

    Elionaldo Fernandes Julião

    Full Text Available RESUMO: Embora algumas experiências estaduais de educação para jovens e adultos em situação de restrição e privação de liberdade remontem há algumas décadas, somente a partir de 2005 é que se iniciam no Brasil encaminhamentos para implementação de uma política propriamente nacional, quando os Ministérios da Educação e da Justiça iniciaram uma proposta de articulação para implementação de Programa Nacional de Educação para o Sistema Penitenciário, formulando as suas diretrizes. Fundamentado em uma concepção crítica sobre o papel do sistema penitenciário na sociedade contemporânea, analisando as suas perspectivas políticas e pedagógicas, principalmente articulando os conceitos de garantias de direitos, políticas públicas, incompletude institucional e socialização, este artigo se propõe a investir na discussão sobre o papel da educação no sistema penitenciário, mais precisamente sobre a escola localizada no espaço carcerário.

  13. Direito do poeta na literatura de cordel

    Directory of Open Access Journals (Sweden)

    Sale Mário Gaudêncio

    Full Text Available Este artigo apresenta uma análise situacional dos direitos autorais na literatura de cordel, especialmente no que se refere à proteção moral e patrimonial que é dada aos poetas populares. Justifica-se o estudo em função de não haver profundas nem atuais discussões teóricas sobre a preservação moral e patrimonial em torno das obras de cordel. Utiliza-se como metodologia a pesquisa bibliográfica relacionada a um corpusque analisa os folhetos impressos por poetas da literatura de cordel. O estudo mostra como resultados o estabelecimento de um modelo alternativo de prazos para os direitos autorais na poesia popular, além da necessidade de ruptura técnica, política e cultural. Conclui informando sobre a importância de se construir um banco de dados nacional para que se tenha conhecimento pleno do quê e como se está produzindo a literatura de cordel, além de saber quem verdadeiramente está sendo beneficiado com tais produções.

  14. Mechanochemical transformations in Li(Na)AlH4-Li(Na)NH2 systems

    International Nuclear Information System (INIS)

    Dolotko, Oleksandr; Zhang Haiqiao; Ugurlu, Ozan; Wiench, Jerzy W.; Pruski, Marek; Scott Chumbley, L.; Pecharsky, Vitalij

    2007-01-01

    Mechanochemical transformations of tetrahydroaluminates and amides of lithium and sodium have been investigated using gas volumetric analysis, X-ray powder diffraction, solid-state nuclear magnetic resonance (NMR) and transmission electron microscopy. In a transformation of LiAlH 4 and LiNH 2 taken in an 1:1 molar ratio, the amount of released hydrogen (6.6 wt.% after 30 min ball milling) was higher than in any known one pot mechanochemical process involving a hydrogen-containing solid. A total of 4.3 wt.% of hydrogen is released by the NaAlH 4 -NaNH 2 system after 60 min ball milling; and 5.2 wt.% H 2 is released when LiAlH 4 and NaNH 2 or NaAlH 4 and LiNH 2 are ball milled for 90 min and 120 min, respectively. All transformations proceed at room temperature. The mechanism of the overall transformation MAlH 4 (s) + MNH 2 (s) → 2MH(s) + AlN(s) + 2H 2 (g) was identified based on detailed spectroscopic analysis of the intermediate (M 3 AlH 6 ) and final products of the ball milling process

  15. Aspectos valorizados por porfissionais de enfermagem na higiene pessoal e na higiene corporal do paciente

    Directory of Open Access Journals (Sweden)

    Elóide André Oliveira

    2003-10-01

    Full Text Available Survey descritivo, com o qual se objetivou identificar que aspectos da higiene corporal são valorizados pelos componentes da equipe de enfermagem, na higiene corporal pessoal e na higiene corporal do paciente. A pesquisa foi desenvolvida em oito instituições públicas de saúde e a amostra foi composta por 126 profissionais de enfermagem, correspondendo a 12,8% do total de 986 componentes das equipes de enfermagem destas instituições. Na higiene corporal pessoal, chamou a atenção o fato de que os cuidados com as unhas e com os cabelos tenham suplantado, no número de citações dos profissionais de enfermagem, aspectos básicos como o cuidado com as mãos. Na higiene corporal do paciente, o banho foi o aspecto considerado mais importante pelas três categorias profissionais; a higiene oral, pelas(os enfermeiras(os e auxiliares de enfermagem; e as unhas, pelas(os enfermeiras(os e técnicas(os de enfermagem.

  16. A coprecipitation technique to prepare NaNbO3 and NaTaO3

    Indian Academy of Sciences (India)

    Unknown

    (V) oxide, tantalum(V) oxide, sodium hydroxide, ethyl alcohol, am- monium carbonate and standard ammonia solution were used and all the starting materials were of AR grade. (Loba chemie). A stoichiometric amount of NaOH was dissolved ...

  17. A capoeira na escola e na Educação Física

    Directory of Open Access Journals (Sweden)

    Vinicius Thiago Melo

    2012-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-8042.2011v23n37p190 Este é um ensaio de revisão bibliográfica que aborda a temática da capoeira na Escola e na Educação Física. A análise de alguns documentos oficiais demonstra que a capoeira estabelece relações concretas com a questão da educação das relações étnico-raciais e com a disciplina Educação Física. No entanto, verifica-se que nem sempre esta modalidade é reconhecida pelas suas possibilidades de participação no processo educativo, mas sim, em uma perspectiva secundária de compensação das tensões da sala de aula e auxílio no controle do comportamento e disciplina dos alunos. Assim, procurou-se refletir e fazer alguns apontamentos sobre o modo pelo qual esta prática cultural tem sido tratada na escola e na Educação Física.

  18. High-temperature phases of NaNbO3 and NaTaO3

    International Nuclear Information System (INIS)

    Darlington, C.N.W.

    1999-01-01

    The high-temperature phases of the perovskites sodium niobate, NaNbO 3 , and sodium tantalate, NaTaO 3 , have been re-examined using the high-resolution powder diffractometer HRPD at the ISIS neutron spallation source; the two materials show the same sequence of phases with tilted octahedra. Diffraction patterns were measured every 5 K allowing structural changes with temperature within a single phase to be determined for the first time. Previous structure determinations within one phase had been performed at a single temperature only. The octahedra are tilted about pseudocubic left angle 100 right angle directions and are also deformed; the magnitude of the deformation is shown to be proportional to the square of the angle of tilt as expected from a phenomenological theory applied to such transitions. The structures of NaNbO 3 between 753 and 793 K and of NaTaO 3 below 758 K are not as reported in the literature. (orig.)

  19. Na-K-Interdiffusion in Alkali Feldspars

    Science.gov (United States)

    Schaeffer, A.-K.; Petrishcheva, E.; Rhede, D.; Abart, R.

    2012-04-01

    Exchange experiments between crystallographically oriented plates of gem-quality alkali feldspar (XOr 0.85) with NaCl/KCl melts have been conducted at 850° and 920° C. The melt composition was varied systematically between XKCl 0.6 and 1 to induce a shift of the feldspar composition towards more Na-rich as well as K-rich compositions (XOr 0.74 to 1). We applied 40-times molar excess of cations in the melt to ensure constant concentration boundary conditions for cation exchange. Depending on the direction of the composition shift diffusion profiles with different geometries develop. After a shift towards more K-rich compositions the diffusion profile shows two plateaus representing the unexchanged core and the exchanged rim in equilibrium with the melt, respectively. The exchange front between the two plateaus has an inflection point and propagates through the crystal with t1/2. Its width depends on the composition difference between the exchanged and unexchanged domains of the grain as well as crystallographic direction. The profiles that develop during a shift towards more Na-rich compositions lack an inflection point. If XOr is shifted by more than 10 mole-% crack systems begin to develop due to composition strain associated with the substitution of K+ by the smaller Na+ion. While the propagation rate of the fronts is roughly equal in all crystallographic directions, the profiles measured in the direction normal to (001) are always narrower than those normal to (010). This indicates a marked anisotropy in interdiffusion which appears fastest in the direction perpendicular to (001), i.e. c*. The observed geometry of the diffusion fronts can be explained by a composition dependence of the interdiffusion coefficient. This dependence was first described by Christoffersen et al. (1983) but these authors used a different experimental setup and only had reliable data for intermediate compositions. From our data we could extract the interdiffusion coefficient for high

  20. Efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl

    Directory of Open Access Journals (Sweden)

    Maíra do PRADO

    Full Text Available Resumo Introdução O tratamento de plasma é uma tecnologia eficaz que pode manter as propriedades internas dos materiais inalteradas após o tratamento, modificando apenas a superfície. Objetivo Avaliar o efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl 6%. Material e método Foram utilizados 60 incisivos bovinos. A coroa foi removida, a raiz foi dividida e as faces planificadas, totalizando 120 segmentos referentes ao terço cervical. As amostras foram divididas em dois grupos: controle (imersa em NaOCl 6%, lavada com água destilada, seca, imersa em EDTA 17%, lavada e seca e plasma de oxigênio (após tratamento descrito no grupo controle, plasma de oxigênio foi aplicado por 30 s. As amostras foram avaliadas qualitativamente em relação à topografia por microscopia eletrônica de varredura, utilizando-se microfotografias com ampliação de 1.000×. O goniômetro Ramé-hart foi utilizado para a mensuração do ângulo de contato entre as superfícies e as seguintes soluções foram utilizadas: água, etilenoglicol e di-iodometano. Em seguida, a energia de superfície, representada pelas componentes polar e dispersiva, foi calculada. Avaliou-se também o escoamento dos cimentos Pulp Canal Sealer EWT (PCS e Real Sal SE (RS na superfície dentinária. Os dados foram analisados estatisticamente utilizando os testes Kruskal-Wallis e Mann-Whitney U (p<0,05. Resultado O tratamento com plasma levou à formação de uma camada semelhante à smear layer na superfície dentinária. Este tratamento levou a um aumento da energia de superfície e da componente polar, favorecendo a hidrofilicidade da superfície. Entretanto, desfavoreceu o escoamento do cimento PCS e não influenciou no escoamento do cimento RS. Conclusão O plasma de oxigênio ocasionou mudanças topográficas na superfície dentinária, favorecendo a hidrofilicidade desta. Contudo, não favoreceu o escoamento dos cimentos endodônticos na dentina.

  1. Diffusion of Na+ AND Sr2+ tracers in compacted, saturated Na-bentonite: a predictive model

    International Nuclear Information System (INIS)

    Bourg, I.C.; Sposito, G.; Bourg, A.C.M.

    2005-01-01

    Full text of publication follows: A key characteristic of the porosity of compacted bentonite is that it is composed not only of macro- and meso-pores, but also of nanometer-thin interlayer pores. The interlayer pore water is in intimate contact with the negatively charged clay, and has a high cation concentration. Anions are strongly excluded from this region. The fluids present in interlayer pores and in the larger pores of compacted, saturated bentonite or montmorillonite have been described as distinct aqueous phases. This distinction has allowed successful explanations of, e.g., chemo-mechanical coupling in clays. However, it is not used in current models of the diffusion of tracers in compacted, saturated bentonite. We have developed a model of the diffusion of tracers in compacted, saturated Na-bentonite in which the interlayers and larger pores are described as parallel diffusion paths [1]. This model has allowed us to successfully describe the mean principal value of the apparent diffusivity tensor of water tracers in several one-dimensionally compacted, saturated Na-bentonites, in a broad range of partial montmorillonite dry density, using the direction-averaged tortuosity (τ = 1.9 ± 0.6) as a single fitted parameter [2]. We report on the application of the same model to the diffusion of Na + and Sr 2+ tracers in compacted, saturated Na-bentonite. Our model successfully predicts the ratio of the apparent diffusivities of cationic and water tracers, with no fitted parameters, as a function of both partial montmorillonite dry density and ionic strength. Furthermore, we show that a relation between the activation energy of diffusion of Na+ tracers and the partial montmorillonite dry density of Na-bentonite can be derived from our model, and can be fit to experimental data. [1] Diffusion of Water and Inorganic Ions in Compacted Saturated Bentonite, I.C. Bourg (2004), Ph.D. thesis, University of California, Berkeley; [2] Diffusion of Water Tracers in

  2. Stimulation of Na+/K+ ATPase activity and Na+ coupled glucose transport by β-catenin

    International Nuclear Information System (INIS)

    Sopjani, Mentor; Alesutan, Ioana; Wilmes, Jan; Dermaku-Sopjani, Miribane; Lam, Rebecca S.; Koutsouki, Evgenia; Jakupi, Muharrem; Foeller, Michael; Lang, Florian

    2010-01-01

    Research highlights: → The oncogenic transcription factor β-catenin stimulates the Na + /K + -ATPase. → β-Catenin stimulates SGLT1 dependent Na + , glucose cotransport. → The effects are independent of transcription. → β-Catenin sensitive transport may contribute to properties of proliferating cells. -- Abstract: β-Catenin is a multifunctional protein stimulating as oncogenic transcription factor several genes important for cell proliferation. β-Catenin-regulated genes include the serum- and glucocorticoid-inducible kinase SGK1, which is known to stimulate a variety of transport systems. The present study explored the possibility that β-catenin influences membrane transport. To this end, β-catenin was expressed in Xenopus oocytes with or without SGLT1 and electrogenic transport determined by dual electrode voltage clamp. As a result, expression of β-catenin significantly enhanced the ouabain-sensitive current of the endogeneous Na + /K + -ATPase. Inhibition of vesicle trafficking by brefeldin A revealed that the stimulatory effect of β-catenin on the endogenous Na + /K + -ATPase was not due to enhanced stability of the pump protein in the cell membrane. Expression of β-catenin further enhanced glucose-induced current (Ig) in SGLT1-expressing oocytes. In the absence of SGLT1 Ig was negligible irrespective of β-catenin expression. The stimulating effect of β-catenin on both Na + /K + ATPase and SGLT1 activity was observed even in the presence of actinomycin D, an inhibitor of transcription. The experiments disclose a completely novel function of β-catenin, i.e. the regulation of transport.

  3. Recent results and prospects for NA62 experiment

    Science.gov (United States)

    Martellotti, Silvia; Aglieri Rinella, G.; Aliberti, R.; Ambrosino, F.; Ammendola, R.; Angelucci, B.; Antonelli, A.; Anzivino, G.; Arcidiacono, R.; Azhinenko, I.; Balev, S.; Barbanera, M.; Bendotti, J.; Biagioni, A.; Bician, L.; Biino, C.; Bizzeti, A.; Blazek, T.; Blik, A.; Bloch-Devaux, B.; Bolotov, V.; Bonaiuto, V.; Boretto, M.; Bragadireanu, M.; Britton, D.; Britvich, G.; Brunetti, M. B.; Bryman, D.; Bucci, F.; Butin, F.; Capitolo, E.; Capoccia, C.; Capussela, T.; Cassese, A.; Catinaccio, A.; Cecchetti, A.; Ceccucci, A.; Cenci, P.; Cerny, V.; Cerri, C.; Checcucci, B.; Chikilev, O.; Chiozzi, S.; Ciaranfi, R.; Collazuol, G.; Conovaloff, A.; Cooke, P.; Cooper, P.; Corradi, G.; Cortina Gil, E.; Costantini, F.; Cotorobai, F.; Cotta Ramusino, A.; Coward, D.; D'Agostini, G.; Dainton, J.; Dalpiaz, P.; Danielsson, H.; Degrange, J.; De Simone, N.; Di Filippo, D.; Di Lella, L.; Di Lorenzo, S.; Dixon, N.; Doble, N.; Dobrich, B.; Duk, V.; Elsha, V.; Engelfried, J.; Enik, T.; Estrada, N.; Falaleev, V.; Fantechi, R.; Fascianelli, V.; Federici, L.; Fedotov, S.; Fiorini, M.; Fry, J.; Fu, J.; Fucci, A.; Fulton, L.; Gallorini, S.; Galeotti, S.; Gamberini, E.; Gatignon, L.; Georgiev, G.; Gianoli, A.; Giorgi, M.; Giudici, S.; Glonti, L.; Goncalves Martins, A.; Gonnella, F.; Goudzovski, E.; Guida, R.; Gushchin, E.; Hahn, F.; Hallgren, B.; Heath, H.; Herman, F.; Husek, T.; Hutanu, O.; Hutchcroft, D.; Iacobuzio, L.; Iacopini, E.; Imbergamo, E.; Jamet, O.; Jarron, P.; Jones, E.; Kampf, K.; Kaplon, J.; Kekelidze, V.; Kholodenko, S.; Khoriauli, G.; Khotyantsev, A.; Khudyakov, A.; Kiryushin, Yu.; Kleimenova, A.; Kleinknecht, K.; Kluge, A.; Koval, M.; Kozhuharov, V.; Krivda, M.; Kucerova, Z.; Kudenko, Y.; Kunze, J.; Lamanna, G.; Latino, G.; Lazzeroni, C.; Lehmann-Miotto, G.; Lenci, R.; Lenti, M.; Leonardi, E.; Lichard, P.; Lietava, R.; Litov, L.; Lollini, R.; Lomidze, D.; Lonardo, A.; Lupi, M.; Lurkin, N.; McCormick, K.; Madigozhin, D.; Maire, G.; Mandeiro, C.; Mannelli, I.; Mannocchi, G.; Mapelli, A.; Marchetto, F.; Marchevski, R.; Martellotti, S.; Massarotti, P.; Massri, K.; Matak, P.; Maurice, E.; Mefodev, A.; Menichetti, E.; Minucci, E.; Mirra, M.; Misheva, M.; Molokanova, N.; Morant, J.; Morel, M.; Moulson, M.; Movchan, S.; Munday, D.; Napolitano, M.; Neri, I.; Newson, F.; Norton, A.; Noy, M.; Nuessle, G.; Numao, T.; Obraztsov, V.; Ostankov, A.; Padolski, S.; Page, R.; Palladino, V.; Paoluzzi, G.; Parkinson, C.; Pedreschi, E.; Pepe, M.; Perez Gomez, F.; Perrin-Terrin, M.; Peruzzo, L.; Petrov, P.; Petrucci, F.; Piandani, R.; Piccini, M.; Pietreanu, D.; Pinzino, J.; Polenkevich, I.; Pontisso, L.; Potrebenikov, Yu.; Protopopescu, D.; Raffaelli, F.; Raggi, M.; Riedler, P.; Romano, A.; Rubin, P.; Ruggiero, G.; Russo, V.; Ryjov, V.; Salamon, A.; Salina, G.; Samsonov, V.; Santoni, C.; Saracino, G.; Sargeni, F.; Semenov, V.; Sergi, A.; Serra, M.; Shaikhiev, A.; Shkarovskiy, S.; Skillicorn, I.; Soldi, D.; Sotnikov, A.; Sougonyaev, V.; Sozzi, M.; Spadaro, T.; Spinella, F.; Staley, R.; Sturgess, A.; Sutcliffe, P.; Szilasi, N.; Tagnani, D.; Trilov, S.; Valdata-Nappi, M.; Valente, P.; Vasile, M.; Vassilieva, T.; Velghe, B.; Veltri, M.; Venditti, S.; Vicini, P.; Volpe, R.; Vormstein, M.; Wahl, H.; Wanke, R.; Wertelaers, P.; Winhart, A.; Winston, R.; Wrona, B.; Yushchenko, O.; Zamkovsky, M.; Zinchenko, A.; NA62 Collaboration

    2017-04-01

    The K+ →π+ ν ν ‾ decay is theoretically one of the cleanest meson decays and so a good place to look for indirect effects of new physics complementary to LHC searches. The NA62 experiment at CERN is designed to measure the branching ratio of this decay with 10% precision. NA62 was commissioned in October 2014, took data in pilot runs in 2014 and 2015. The NA62 experimental setup is illustrated and data quality is reported.

  4. RAZVOJ APLIKACIJE PRETOČNEGA VIDEA NA MOBILNEM TELEFONU

    OpenAIRE

    Horvat, Jernej

    2012-01-01

    Diplomsko delo obravnava prenos video signala iz mobilnega telefona na TV. Prenos poteka preko Wi-Fi omrežja. Na mobilnem telefonu je nameščena ustrezna Android aplikacija, ki omogoča direkten prenos video signala in nalaganje na TV sprejemnik. Pomemben dejavnik, ki prispeva, da je ta proces mogoč, je sistem IMS (IP multimedijski podsistem), ki predstavlja omrežja naslednje generacije.

  5. Transcriptional regulators of Na, K-ATPase subunits

    OpenAIRE

    Zhiqin eLi; Sigrid A Langhans

    2015-01-01

    The Na,K-ATPase classically serves as an ion pump creating an electrochemical gradient across the plasma membrane that is essential for transepithelial transport, nutrient uptake and membrane potential. In addition, Na,K-ATPase also functions as a receptor, a signal transducer and a cell adhesion molecule. With such diverse roles, it is understandable that the Na,K-ATPase subunits, the catalytic alpha-subunit, the beta-subunit and the FXYD proteins, are controlled extensively during developme...

  6. Sociologia na complexidade Sociology in complexity

    Directory of Open Access Journals (Sweden)

    Gilson Lima

    2006-06-01

    Full Text Available O artigo se propõe a fazer uma introdução didática e informativa e, ao mesmo tempo, aprofundada sobre as conseqüências da emergência do paradigma da complexidade para a Sociologia. No desenrolar da narrativa, faz comparações, o que permite ao leitor não familiarizado com a temática da ciência identificar as diferenças macroparadigmáticas pré-modernas, da modernidade simples e da emergência do paradigma da complexidade. Define e exemplifica, sempre que possível, os termos, afirmações e princípios significativos para uma melhor compreensão do tema. Faz, também, inúmeras indicações, no interior da narrativa, de autores e obras, para que aqueles que desejarem continuar, possam mergulhar mais intensamente nos caminhos da sociologia da complexidade. O artigo inicia com uma introdução que define, a partir de Thomas Kuhn, o conceito de paradigma. A seguir, desenvolve de modo comparado, os princípios mais importantes do paradigma da complexidade. E, por fim, chama a atenção para alguns desafios da Sociologia na complexidade, alertando para os riscos da paralisação da complexidade na difícil tarefa de religarmos os saberes diante da hiperespecialização presente na crise do paradigma da modernidade simples.The article is a simultaneously didactic and informative deep introduction on the emergence of the paradigm of complexity for sociology. Along the narrative, we make comparisons, which allows the reader who is not familiar with the themes of science to identify the macro-paradigmatic pre-modern differences from simple modernity and the emergence of the paradigm of complexity. Whenever it is possible, we define and exemplify the terms, assertions, and principles that are significant for an understanding of the theme. We have also made numerous indications of authors and works within the narrative, thus those willing might take a deeper dive in the pathways of sociology of complexity. The article starts with an

  7. RAHNER NA BERLINDA PÓS-CONCILIAR

    Directory of Open Access Journals (Sweden)

    Luciano Campos Lavall

    2004-01-01

    Full Text Available O artigo analisa algumas críticas negativas feitas ao pensamento teológico de Karl Rahner, após sua morte, que tentam desqualificar a sua importância para a ortodoxia católica e o seu distanciamento dos fundamentos do Concílio Vaticano II. Na discussão, enfocada sobretudo no ponto de vista da eclesiologia rahneriana, retoma importante entrevista do mesmo, no ano de sua morte, na qual aparece a sua preocupação com as chances futuras da Igreja, sobretudo na Europa Ocidental, a partir da qual abordam-se as relações entre Cristianismo e Igreja. As estratégias para a organização pastoral do mundo católico são a tônica desta reflexão. Para justificar suas posturas, o artigo termina com uma avaliação global de todo o conjunto teológico de Karl Rahner, redescobrindo nele os pilares mais fundamentais que justificam sua ortodoxia a serviço da fé cristã e católica, mas também a serviço da tomada de consciência de uma fé vivenciada e comprometida por parte da humanidade marcadamente secularizada. ABSTRACT: The article analyses negative criticisms against Rahner’s theological views after his death with the intention of discrediting him and his role in Catholic orthodoxy by distancing him from the fundamentals of Vatican Council II. In the discussion, primarily focused on Rahner’s ecclesiology, the article retakes a significant interview made the same year of Rahner’s death. In this interview his concern for the Church’s future chances, especially regarding Eastern Europe, embarking on relations between Christianity and Church. The strategies for world-wide organization of Catholic ministry predominate this reflection. Justifying its postures, the article concludes with a global evaluation of Rahner’s theology, rediscovering the fundamental pillars which justify his orthodoxy at the service of the Christian and Catholic faith, but also at the service of a conscientious living of a committed faith on behalf of a notably

  8. Characterization of ZnAl cast alloys with Na addition

    Energy Technology Data Exchange (ETDEWEB)

    Gancarz, Tomasz, E-mail: t.gancarz@imim.pl [Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Krakow (Poland); Cempura, Grzegorz [AGH University of Science and Technology, International Centre of Electron Microscopy for Materials Science, Faculty of Metals Engineering and Industrial Computer Science, Krakow (Poland); Skuza, Wojciech [Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Krakow (Poland)

    2016-01-15

    This study was aimed at evaluating the microstructural change and thermal, electrical and mechanical properties with the addition of Na to eutectic ZnAl alloys. Solders based on eutectic ZnAl containing 0.2 to 3.0 (wt.%) of Na were developed for high temperature solder. Differential scanning calorimetry (DSC) measurements were performed to determine the melting temperatures of the alloys. Thermal linear expansion and electrical resistivity measurements were performed over − 50 °C to 300 °C and 30 °C to 300 °C temperature ranges, respectively. The microstructure of the specimens was analyzed using scanning (SEM) and transmission electron microscopy (TEM) techniques. Chemical microanalysis was performed by energy-dispersive X-ray spectroscopy (EDS) on SEM and TEM. The precipitates of NaZn{sub 13} were confirmed by X-ray diffraction (XRD) measurements and selected area electron diffraction (SAED) techniques. The addition of Na to eutectic ZnAl alloy increased the electrical resistivity and reduced the coefficient of thermal expansion; however, the melting point did not change. The mechanical properties, strain and microhardness increased with Na content in alloys. - Highlights: • High temperature soldering materials of ZnAl with Na were designed and characterized. • Precipitates of NaZn{sub 13}were observed and confirmed using TEM and XRD. • Addition of Na to eutectic ZnAl cussed increased mechanical properties. • NaZn{sub 13} caused increased electrical resistivity and microhardness, and reduced the CTE.

  9. Dejavniki psihološkega nasilja na delovnem mestu

    OpenAIRE

    Ilc, Teja

    2011-01-01

    Raziskave na področju delovnih razmer kažejo, da je danes pereč problem ravno psihološko nasilje na delovnem mestu. Posebna oblika psihološkega nasilja na delovnem mestu je mobing, s katerim se v praksi srečujemo vsak dan, vendar se ga pogosto ne zavedamo. Namen magistrske naloge je pojasniti pojem in pomen mobinga v delovnih organizacijah, poiskati možne vzroke in posledice, ki vplivajo na ta pojav, ter predlagati rešitve. Poznavanje mehanizmov, ki povzročajo mobing, njegovih vzrokov in...

  10. VLOGA ETIKE PRI PREPREČEVANJU NADLEGOVANJA NA DELOVNEM MESTU

    OpenAIRE

    Sambolec, Katja

    2013-01-01

    V diplomskem seminarju smo obravnavali temo z naslovom Vpliv etike pri preprečevanju nadlegovanja na delovnem mestu. Tema o nadlegovanju na delovnem mestu, je aktualna že desetletja in glede na gospodarsko krizo, ki ji še ni videti konca, je aktualna še danes. Zaradi prenasičenosti trga s ponudniki iste branže, se posledično v posameznih podjetjih izvajajo pritiski na zaposlene, ki v različnih situacijah vodijo do nadlegovanja. Pri pisanju diplomskega seminarja smo se najprej osredotoči...

  11. Influenza virus neuraminidase (NA): a target for antivirals and vaccines.

    Science.gov (United States)

    Jagadesh, Anitha; Salam, Abdul Ajees Abdul; Mudgal, Piya Paul; Arunkumar, Govindakarnavar

    2016-08-01

    Influenza, the most common infectious disease, poses a great threat to human health because of its highly contagious nature and fast transmissibility, often leading to high morbidity and mortality. Effective vaccination strategies may aid in the prevention and control of recurring epidemics and pandemics associated with this infectious disease. However, antigenic shifts and drifts are major concerns with influenza virus, requiring effective global monitoring and updating of vaccines. Current vaccines are standardized primarily based on the amount of hemagglutinin, a major surface antigen, which chiefly constitutes these preparations along with the varying amounts of neuraminidase (NA). Anti-influenza drugs targeting the active site of NA have been in use for more than a decade now. However, NA has not been approved as an effective antigenic component of the influenza vaccine because of standardization issues. Although some studies have suggested that NA antibodies are able to reduce the severity of the disease and induce a long-term and cross-protective immunity, a few major scientific issues need to be addressed prior to launching NA-based vaccines. Interestingly, an increasing number of studies have shown NA to be a promising target for future influenza vaccines. This review is an attempt to consolidate studies that reflect the strength of NA as a suitable vaccine target. The studies discussed in this article highlight NA as a potential influenza vaccine candidate and support taking the process of developing NA vaccines to the next stage.

  12. O grotesco na imagem publicitária

    OpenAIRE

    Silva, Maria João Barros

    2013-01-01

    O significado da palavra grotesco teve um começo puramente artístico numa descoberta, de imagens de figuras humanas deformadas e alteradas. No entanto, este foi evoluindo e adotando novos significados mais amplos e concretos na atualidade. É possível encontrar vários exemplos do grotesco em várias plataformas, como no cinema, na televisão e na literatura. Neste sentido, para se poder proceder ao estudo desta temática é fundamental a conquista do conhecimento sobre o estatuto do grotesco na pu...

  13. DISKRIMINACIJA PRI ZAPOSLOVANJU IN DELU NA PODLAGI SPOLNE USMERJENOSTI

    OpenAIRE

    Markovič, Polona

    2012-01-01

    Ustavno zagotovljena pravica do enakosti, brez kakršnegakoli razlikovanja na podlagi osebnih okoliščin, predstavlja eno izmed temeljnih človekovih pravic. Za zagotavljanje enakega obravnavanja posameznikov in različnih skupin oseb na vseh področjih družbenega življenja je neizogibno potrebna natančna zakonska opredelitev varstva pred diskriminacijo. Prepoved diskriminacije je pravno regulirana v določilih mnogih dokumentov, sprejetih na mednarodni in nacionalni ravni. Diskriminacijo lahko naj...

  14. Cafeína e desempenho em atividade de endurance?

    OpenAIRE

    Souza Junior, Tácito Pessoa de; Capitani, Caroline Dario; Loturco Filho, Irineu; Viveiros, Luis; Aoki, Marcelo Saldanha

    2012-01-01

    A cafeína é frequentemente consumida por atletas, por causa dos seus possíveis efeitos ergogênicos. É preconizado que a cafeína maximize a performance por agir, independentemente, ou concomitamente, através de 3 mecanismos: 1) aumento da mobilização do cálcio intracelular, 2) aumento na oxidação de ácidos graxos livres e 3) antagonista do receptor de adenosina no sistema nervoso central. Estudos iniciais sugeriram que o efeito ergogênico da cafeína estava relacionado ao aumento da oxidaçã...

  15. Transcriptional regulators of Na, K-ATPase subunits

    Directory of Open Access Journals (Sweden)

    Zhiqin eLi

    2015-10-01

    Full Text Available The Na,K-ATPase classically serves as an ion pump creating an electrochemical gradient across the plasma membrane that is essential for transepithelial transport, nutrient uptake and membrane potential. In addition, Na,K-ATPase also functions as a receptor, a signal transducer and a cell adhesion molecule. With such diverse roles, it is understandable that the Na,K-ATPase subunits, the catalytic alpha-subunit, the beta-subunit and the FXYD proteins, are controlled extensively during development and to accommodate physiological needs. The spatial and temporal expression of Na,K-ATPase is partially regulated at the transcriptional level. Numerous transcription factors, hormones, growth factors, lipids and extracellular stimuli modulate the transcription of the Na,K-ATPase subunits. Moreover, epigenetic mechanisms also contribute to the regulation of Na,K-ATPase expression. With the ever growing knowledge about diseases associated with the malfunction of Na,K-ATPase, this review aims at summarizing the best-characterized transcription regulators that modulate Na,K-ATPase subunit levels. As abnormal expression of Na,K-ATPase subunits have been observed in many carcinoma, we will also discuss transcription factors that are associated with epithelial-to-mesenchymal transition, a crucial step in the progression of many tumors to malignant disease.

  16. Cathode Dependence of Liquid-Alloy Na-K Anodes.

    Science.gov (United States)

    Xue, Leigang; Gao, Hongcai; Li, Yutao; Goodenough, John B

    2018-03-07

    Alkali ions can be plated dendrite-free into a liquid alkali-metal anode. Commercialized Na-S battery technology operates above 300 °C. A low-cost Na-K alloy is liquid at 25 °C from 9.2 to 58.2 wt% of sodium; sodium and/or potassium can be plated dendrite-free in the liquid range at room temperature. The co-existence of two alkali metals in an anode raises a question: whether the liquid Na-K alloy acts as a Na or a K anode. Here we show the alkali-metal that is stripped from the liquid Na-K anode is dependent on the preference of the cathode host. It acts as the anode of a sodium rechargeable cell if the cathode host structure selectively accepts only Na + ions; as the anode of a potassium rechargeable cell if the cathode accepts K + ions in preference to Na + ions. This dual-anode behavior means the liquid Na-K alkali-alloy can be applied as a dendrite-free anode in Na-metal batteries as well as K-metal batteries.

  17. Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jingke; Shields, Emily; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O.; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K.; Ianni, Aldo; Lamere, Edward; Lippincott, W. Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-07-01

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3 to 52 keVnr, covering the whole DAMA/LIBRA energy region for dark matter-Na scattering interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  18. Na/K Pump and Beyond: Na/K-ATPase as a Modulator of Apoptosis and Autophagy.

    Science.gov (United States)

    Felippe Gonçalves-de-Albuquerque, Cassiano; Ribeiro Silva, Adriana; Ignácio da Silva, Camila; Caire Castro-Faria-Neto, Hugo; Burth, Patrícia

    2017-04-21

    Lung cancer is a leading cause of global cancer deaths. Na/K-ATPase has been studied as a target for cancer treatment. Cardiotonic steroids (CS) trigger intracellular signalling upon binding to Na/K-ATPase. Normal lung and tumour cells frequently express different pump isoforms. Thus, Na/K-ATPase is a powerful target for lung cancer treatment. Drugs targeting Na/K-ATPase may induce apoptosis and autophagy in transformed cells. We argue that Na/K-ATPase has a role as a potential target in chemotherapy in lung cancer treatment. We discuss the effects of Na/K-ATPase ligands and molecular pathways inducing deleterious effects on lung cancer cells, especially those leading to apoptosis and autophagy.

  19. Na/K Pump and Beyond: Na/K-ATPase as a Modulator of Apoptosis and Autophagy

    Directory of Open Access Journals (Sweden)

    Cassiano Felippe Gonçalves-de-Albuquerque

    2017-04-01

    Full Text Available Lung cancer is a leading cause of global cancer deaths. Na/K-ATPase has been studied as a target for cancer treatment. Cardiotonic steroids (CS trigger intracellular signalling upon binding to Na/K-ATPase. Normal lung and tumour cells frequently express different pump isoforms. Thus, Na/K-ATPase is a powerful target for lung cancer treatment. Drugs targeting Na/K-ATPase may induce apoptosis and autophagy in transformed cells. We argue that Na/K-ATPase has a role as a potential target in chemotherapy in lung cancer treatment. We discuss the effects of Na/K-ATPase ligands and molecular pathways inducing deleterious effects on lung cancer cells, especially those leading to apoptosis and autophagy.

  20. The NA49 large acceptance hadron detector

    CERN Document Server

    Afanasiev, S V; Appelshäuser, H; Bächler, J; Barna, D; Barnby, L S; Bartke, Jerzy; Barton, R A; Betev, L; Bialkowska, H; Bieser, F; Billmeier, A; Blyth, C O; Böck, R K; Bormann, C; Bracinik, J; Brady, F P; Brockmann, R; Brun, R; Buncic, P; Caines, H L; Cebra, D; Cooper, G E; Cramer, J G; Csató, P; Cyprian, M; Dunn, J; Eckardt, V; Eckhardt, F; Empl, T; Eschke, J; Ferguson, M I; Fessler, H; Fischer, H G; Flierl, D; Fodor, Z; Frankenfeld, Ulrich; Foka, P Y; Freund, P; Friese, V; Ftácnik, J; Fuchs, M; Gabler, F; Gál, J; Ganz, R E; Gazdzicki, M; Gladysz-Dziadus, E; Grebieszkow, J; Günther, J; Harris, J W; Hegyi, S; Henkel, T; Hill, L A; Hlinka, V; Huang, I; Hümmler, H; Igo, G; Irmscher, D; Ivanov, M; Janik, R; Jacobs, P; Jones, P G; Kadija, K; Kolesnikov, V I; Kowalski, M; Lasiuk, B; Lévai, Peter; Liebicher, K; Lynen, U; Malakhov, A I; Margetis, S; Markert, C; Marks, C; Mayes, B W; Melkumov, G L; Mock, A; Molnár, J; Nelson, J M; Oldenburg, M; Odyniec, Grazyna Janina; Pálla, G; Panagiotou, A D; Pestov, Yu N; Petridis, A; Pikna, M; Pimpl, W; Pinsky, L; Piper, A; Porter, R J; Poskanzer, A M; Poziombka, S; Prindle, D J; Pühlhofer, F; Rauch, W; Reid, J G; Renfordt, R E; Retyk, W; Ritter, H G; Röhrich, D; Roland, C; Roland, G; Rudolph, H; Rybicki, A; Sammer, T; Sandoval, A; Sann, H; Schäfer, E; Schmidt, R; Schmischke, D; Schmitz, N; Schönfelder, S; Semenov, A Yu; Seyboth, J; Seyboth, P; Seyerlein, J; Siklér, F; Sitár, B; Skrzypczak, E; Squier, G T A; Stelzer, H; Stock, Reinhard; Strmen, P; Ströbele, H; Struck, C; Susa, T; Szarka, I; Szentpétery, I; Szymanski, P; Sziklai, J; Toy, M; Trainor, T A; Trentalange, S; Ullrich, T S; Vassiliou, Maria; Veres, G I; Vesztergombi, G; Vranic, D; Wang, F; Weerasundara, D D; Wenig, S; Whitten, C; Wieman, H H; Wienold, T; Wood, L; Yates, T A; Zimányi, J; Zhu, X Z; Zybert, R

    1999-01-01

    The NA49 detector is a wide acceptance spectrometer for the study of hadron production in p+p, p+A, and A+A collisions at the CERN SPS. The main components are 4 large volume TPCs for tracking and particle identification via $dE/dx$. TOF scintillator arrays complement particle identification. Calorimeters for transverse energy determination and triggering, a detector for centrality selection in p+A collisions, and beam definition detectors complete the set-up. A description of all detector components is given with emphasis on new technical realizations. Performance and operational experience are discussed in particular with respect to the high track density environment of central Pb+Pb collisions.

  1. Sexo e sexualidade na terceira idade

    OpenAIRE

    Nery, Valeria Alves da Silva; UESB; Valença, Tatiane Dias Casimiro; UESB

    2014-01-01

    Muitos idosos ainda encaram o envelhecer como sinônimo de decadência e isolamento, doenças e peso social, sendo que a sociedade impõe aos idosos, tabus, privando-lhe de re-pensar a sexualidade, o corpo, o prazer, a prática do sexo, levando-os a enfrentar várias dificuldades de adaptação a esse estágio da vida. O objetivo geral deste estudo foi Analisar as percepções sobre sexo e sexualidade na terceira idade. Quanto aos objetivos específicos, busca-se: averiguar se os idosos continuam tendo v...

  2. Bullying: ato esburacado na angústia

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Soares Ornellas

    2012-04-01

    Full Text Available A noção de afeto está no campo do (desprazer, resultante de uma experiência afetiva de satisfação ou insatisfação, e que se manifesta nas necessidades do sujeito. Pode-se dizer que o afeto envolve a ambivalência de sentimentos, do mais agradável ao mais insuportável, e desempenha um papel estruturante para que o sujeito reencontre sua estrutura psíquica, exercendo uma ação mediadora e decisiva sobre a constituição do sujeito do desejo, orientando o seu projeto de vida, sua profissão, sua opção sexual, etc. Essa ambivalência de afetos deve ser exercitada na educação familiar e escolar, na fala e na escuta que o afeto (desprazeroso tem relevância e parece ser silenciado. O desprazer pode ser escandido pelos sintomas medo, depressão, irritabilidade, ansiedade, humilhação. Assim posto o bullying é também conhecido como a síndrome da humilhação. O objetivo da humilhação é a tentativa de destruição do sujeito; a perda da identificação revela um fantasma, na medida em que própria vítima se sente culpada por sofrer ou por estar sofrendo um ato esburacado porque uma das peças não é encontrada e, em lugar do encaixe, o que se mostra é um buraco, o que provoca a angústia entre quem perde e aquele que ganha. ABSTRACT: The notion of affect is thus in the field of (dis pleasure, resulting from an affective experience of satisfaction or dissatisfaction, and that manifests itself on the needs of the subject. You could say that the affection involves the ambivalence of feelings, the more enjoyable the more unbearable, and plays a structural role for the subject to rediscover his psychic structure, exerting a mediator and decisive action on the constitution of the subject of desire, directing the its design life, your profession, your sexual orientation, etc.. This ambivalence of feelings should be exercised in family education and school, talking and listening that affect (dis pleasure is relevant and appears to be

  3. Redes sociais na internet: Sociabilidades emergentes

    OpenAIRE

    Amaral, Inês

    2016-01-01

    Na actual era da cultura digital é imperativo identificar e compreender os tipos de sociabilidade que emergem das novas práticas e relações que ocorrem no ciberespaço, para que seja possível teorizar sobre realidades sociais que são desenhadas em torno da apropriação do conteúdo e materializadas em plataformas que se assumem como o termómetro de uma sociedade sem determinismo geográfico. A sociabilização em contexto digital reporta-se ao princípio de que um mundo de informação (conteúdos, ...

  4. O retorno do religioso na contemporaneidade

    Directory of Open Access Journals (Sweden)

    Tiago Ribeiro Nunes

    2008-12-01

    Full Text Available O presente trabalho pretende analisar os novos modos de relação, entre a civilização e o sagrado, que emergem no contexto da contemporaneidade. Partindo principalmente das formulações freudianas e lacanianas sobre o tema, nosso objetivo primordial ao longo deste artigo é estabelecer parâmetros para compreender a ocorrência do "retorno ao sagrado no exato momento em que a humanidade enfrenta crises cada vez mais profundas e permanentes. Tal empreendimento nos permitirá verificar até que ponto o fortalecimento dos movimentos religiosos pode ser considerado como uma das conseqüências da queda dos referenciais que se realiza na contemporaneidade.

  5. Topicos na classe dos grafos clique

    OpenAIRE

    Luis Arturo Perez Lozada

    1996-01-01

    Resumo: Uma dique de um grafo G é um conjunto de vértices que induz um subgrafo completo maximal de G. O grafo dique K(G) de um grafo G é o grafo interseção das diques de G. Indutivamente define-se o i-ésimo grafo dique iterado de G como Ki(G) = K(Ki-l(G)). Apresenta-se de maneira organizada uma compilação de pesquisas realizadas nos últimos anos a respeito de diversos tópicos na dasse dos grafos dique, entre eles: o estudo das propriedades dos grafos dique de conhecidas dasses de grafos; a c...

  6. A TATUAGEM: NO CORPO E NA ESCRITA

    OpenAIRE

    Coito, Roselene de Fátima

    2007-01-01

    Entendendo a narrativa como uma negociação de sentidos, faremos uma reflexão sobre identidade a partir de marcas. A identidade na construção discursiva, no conto A hora e a vez de Augusto Matraga, de Guimarães Rosa, vale-se de dois olhares nesta reflexão: da marca tatuada no corpo de Matraga e de Matraga como marca circular da narrativa, pois Matraga é a marca da brasa que queima com ferro o corpo e também a página em branco tatuada pela escrita, o que faz do corpo, a escrita e da escrita, o ...

  7. Solubility of NaNd(CO3)2.6H2O(c) in concentrated Na2CO3 and NaHCO3 solutions

    International Nuclear Information System (INIS)

    Rao, L.; Rai, D.; Felmy, A.R.; Fulton, R.W.; Novak, C.F.

    1996-01-01

    NaNd(CO 3 ) 2 x 6 H 2 O(c) was identified to be the final equilibrium solid phase in suspensions containing concentrated sodium carbonate (0.1 to 2.0 M) and sodium bicarbonate (0.1 to 1.0 M), with either NaNd(CO 3 ) 2 x 6 H 2 O(c) or Nd 2 (CO 3 ) 3 x xH 2 O(s) as initial solids. A thermodynamic model, based on Pitzer's specific into-interaction approach, was developed to interpret the solubility of NaNd(CO 3 ) 2 x 6 H 2 O(c) as functions of sodium carbonate and sodium bicarbonate concentrations. In this model, the solubility data of NaNd(CO 3 ) 2 x 6 H 2 O(c) were explained by assuming the formation of NdCO 3 + , Nd(CO 3 ) 2 - and Nd(CO 3 ) 3 3- species and invoking the specific ion interactions between Na + and Nd(CO 3 ) 3 3- . Ion interaction parameters for Na + -Nd(CO 3 ) 3 3- were developed to fit the solubility data. Based on the model calculations, Nd(CO 3 ) 3 3- was the predominant aqueous neodymium species in 0.1 to 2 M sodium carbonate and 0.1 to 1 M sodium bicarbonate solutions. The logarithm of the NaNd(CO 3 ) 2 x 6 H 2 O solubility product (NaNd(CO 3 ) 2 x 6 H 2 O(c)=Na + +Nd 3+ +2 CO 3 2- +6 H 2 O) was calculated to be -21.39. This model also provided satisfactory interpretation of the solubility data of the analogous Am(III) system in less concentrated carbonate and bicarbonate solutions. (orig.)

  8. Porta-enxertos utilizados na citricultura

    Directory of Open Access Journals (Sweden)

    Schäfer Gilmar

    2001-01-01

    Full Text Available A muda cítrica é o insumo mais importante na formação de um pomar. As características mais importantes da muda cítrica são a origem do enxerto e do porta-enxerto, a qualidade do sistema radicular e a sua sanidade. Os porta-enxertos são capazes de influenciar várias características horticulturais e sanitárias nas árvores e nos frutos cítricos, como: sólidos solúveis totais, tamanho da copa e do fruto, resistência a moléstias e ao frio, distribuição da raízes, etc. O principal porta-enxerto utilizado no Brasil (cerca de 80% é o limoeiro ?Cravo? (Citrus limonia Osbeck cv. Cravo. No Rio Grande do Sul, mais especificamente, destaca-se o Poncirus trifoliata (L. Raf em mais de 90% dos pomares. Isso torna a citricultura vulnerável ao surgimento de moléstias que afetem estes porta-enxertos, como ocorreu na década de 40 em todo o Brasil com a 'Tristeza' dos citros em plantas enxertadas sobre laranjeira azeda, e, mais recentemente, com o 'declínio'. Assim, o conhecimento das características dos diversos porta-enxertos e de algumas particularidades do uso destes é de grande importância para a diversificação e escolha do porta-enxerto a ser utilizado pelo citricultor.

  9. Videogames e o aprender na complexidade

    Directory of Open Access Journals (Sweden)

    Paula Cristina Turcatto

    2016-06-01

    Full Text Available Ao conceber-se esta pesquisa, levou-se em consideração que cada ser humano aprende do seu modo pessoal e único, portanto, a proposta é pensar os videogames na sua relação com o Paradigma da Complexidade. Esta pesquisa teve como objetivo proporcionar um ambiente de encontro com diversos jogos de videogame, buscando instaurar a experimentação do novo, a abertura para o conhecer, ao habitar espaços inventivos, que valorizam a plasticidade e flexibilidade. Trata-se de uma pesquisa qualitativa, pois se propôs a trabalhar com os aspectos subjetivos como uma dimensão inseparável do conhecer. Foram 8 sujeitos de pesquisa – adolescentes – com os quais foram realizados 15 encontros, nos quais os mesmos estiveram em contato com diversos jogos de videogame. Foram utilizados diários de bordo para o registro das vivências, ancorados na metodologia cartográfica para tratamento dos registros. Os videogames propiciaram espaços para a emergência de diferentes formas de vivenciar a narrativa. Apesar de os jogos serem pré-moldados, os percursos produzidos, assim como as produções simbólicas frente ao contexto do jogo foram individuais. Jogar videogame relacionou-se ao posicionamento criador, de escrever as circunstâncias sob as quais as ações do jogo refletiram nas experiências vivenciadas pelo jogador.

  10. Insulin regulation of (Na+, K+)-ATPase

    International Nuclear Information System (INIS)

    Lytton, J.

    1985-01-01

    This thesis describes an investigation into the mechanism of insulin stimulation of (Na + ,K + )=ATPase in rat adipocytes. Two molecular forms of the catalytic subunit of the enzyme were identified and denoted α and α(+), due to their similarity to those isozymes previously described from rat brain. Insulin specifically stimulated the α(+) form of the enzyme. The two forms of the enzyme had quite different affinities for intracellular sodium ion; insulin affected only the lower affinity of α(+), shifting it toward a higher value. However, the sodium affinity of (Na + ,K + )-ATPase activity in isolated membranes was equally high for both forms of the enzyme. This suggests that the difference in sodium affinity between the two forms observed in the cell is not inherent within the structure of the sodium pump, but must depend upon a selective interaction with another molecule which has been lost upon membrane isolation. Immunoprecipitation of both the catalytic subunits either from extracts of whole cells which had been labelled with [ 32 P] orthophosphate, or from membranes which had been labelled with γ-[ 32 P]ATP demonstrated that less than 1 in 100 molecules had a covalently bound phosphate insulin had no influence on this value. The amino terminal sequences of the first 4 amino acids of the catalytic subunits of both α (isolated from rat kidney) and α(+) (from rat brainstem axolemma) were determined. The result shows two highly homologous but clearly different molecules. It can thus be concluded that the insulin sensitive version of the enzyme is not derived from the common α form by a post-translational modification

  11. LUZ, MELATONINA E ESTRESSE OXIDATIVO NA PISCICULTURA

    Directory of Open Access Journals (Sweden)

    Claudio Alberto Gellis de Mattos Dias

    2013-12-01

    Full Text Available Em peixes, como nos mamíferos, partes do sistema nervoso estão envolvidas em mecanismos para regulação dos sistemas corporais em sintonia com o meio. O fotoperíodo é traduzido em informações fisiológicas a partir da secreção de melatonina.Parece não haver barreiras morfofisiológicas para esta indolamina, isto é, a melatonina perfunde-se rapidamente em cada célula do organismo e em alguns casos interage com receptores e membrana situados na superfície celular, e parece estar ligada à ingestão de alimentos, crescimento e atividade locomotora de peixes. São moléculas importantes metabolizando espécies reativas de oxigênio a produtos inativos e, portanto, reduzindo o dano oxidativo.Este trabalho tem por objetivo fazer um breve levantamento em artigos recentes sobre luminosidade, melatonina e o estresse oxidativo em peixes, e correlaciona-los com piscicultura. Concluímos que a luminosidade parece estar ligada a produção de melatonina, e esta molécula antioxidante, que favorece a redução do estresse oxidativo, parecem melhorar o desempenho na produção de peixes em criadouros. Palavras-chave: Melatonina, estresse oxidativo, piscicultura. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v3n3p169-176

  12. Vogais na amazônia paraense

    Directory of Open Access Journals (Sweden)

    Regina Cruz

    2012-01-01

    Full Text Available Este artigo trata essencialmente de uma apresentação das ações do projeto institucional Norte Vogais vinculado ao Diretório Nacional PROBRAVO. O artigo fornece uma ideia precisa de como a equipe da UFPA vinculada ao PROBRAVO está conduzindo suas investigações sobre a variedade do português falada no Pará. O projeto Norte Vogais conta com amostras de fala de trezentos e dezoito informantes nativos do Pará no seu banco de dados. As descrições sociolinguísticas empreendidas pela equipe da UFPA priorizaram a investigação de três aspectos fonéticos em particular: a a variação das vogais médias pretônicas; b a variação das vogais médias postônicas mediais e; c a nasalidade alofônica. Os resultados obtidos reforçam a hipótese de Silva Neto (1957 de que o Pará compreenderia uma ilha dialetal na classificação de Antenor Nascente entre os dialetos do Norte do Brasil. Com o objetivo de refinar as descrições sociolingüísticas, duas novas ações se impuseram: a o mapeamento da situação sociolinguística das áreas de contato interdialetal no Pará e; b a análise acústica do sistema vocálico do português falado na Amazônia Paraense.

  13. VOGAIS NA AMAZÔNIA PARAENSE

    Directory of Open Access Journals (Sweden)

    Regina Fernandes Cruz

    2012-12-01

    Full Text Available Este artigo trata essencialmente de uma apresentação das ações do projeto institucional Norte Vogais vinculado ao Diretório Nacional PROBRAVO. O artigo fornece uma ideia precisa de como a equipe da UFPA vinculada ao PROBRAVO está conduzindo suas investigações sobre a variedade do português falada no Pará. O projeto Norte Vogais conta com amostras de fala de trezentos e dezoito informantes nativos do Pará no seu banco de dados. As descrições sociolinguísticas empreendidas pela equipe da UFPA priorizaram a investigação de três aspectos fonéticos em particular: a a variação das vogais médias pretônicas; b a variação das vogais médias postônicas mediais e; c a nasalidade alofônica. Os resultados obtidos reforçam a hipótese de Silva Neto (1957 de que o Pará compreenderia uma ilha dialetal na classificação de Antenor Nascente entre os dialetos do Norte do Brasil. Com o objetivo de refinar as descrições sociolingüísticas, duas novas ações se impuseram: a o mapeamento da situação sociolinguística das áreas de contato interdialetal no Pará e; b a análise acústica do sistema vocálico do português falado na Amazônia Paraense.

  14. Mercury's Na Exosphere from MESSENGER Data

    Science.gov (United States)

    Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. El; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

    2012-01-01

    MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UWS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft :0 infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The portion of the hot/cold source appears to be highly variable.

  15. RNA adducts with Na 2SeO 4 and Na 2SeO 3 - Stability and structural features

    Science.gov (United States)

    Nafisi, Shohreh; Manouchehri, Firouzeh; Montazeri, Maryam

    2011-12-01

    Selenium compounds are widely available in dietary supplements and have been extensively studied for their antioxidant and anticancer properties. Low blood Se levels were found to be associated with an increased incidence and mortality from various types of cancers. Although many in vivo and clinical trials have been conducted using these compounds, their biochemical and chemical mechanisms of efficacy are the focus of much current research. This study was designed to examine the interaction of Na 2SeO 4 and Na 2SeO 3 with RNA in aqueous solution at physiological conditions, using a constant RNA concentration (6.25 mM) and various sodium selenate and sodium selenite/polynucleotide (phosphate) ratios of 1/80, 1/40, 1/20, 1/10, 1/5, 1/2 and 1/1. Fourier transform infrared, UV-Visible spectroscopic methods were used to determine the drug binding modes, the binding constants, and the stability of Na 2SeO 4 and Na 2SeO 3-RNA complexes in aqueous solution. Spectroscopic evidence showed that Na 2SeO 4 and Na 2SeO 3 bind to the major and minor grooves of RNA ( via G, A and U bases) with some degree of the Se-phosphate (PO 2) interaction for both compounds with overall binding constants of K(Na 2SeO 4-RNA) = 8.34 × 10 3 and K(Na 2SeO 3-RNA) = 4.57 × 10 3 M -1. The order of selenium salts-biopolymer stability was Na 2SeO 4-RNA > Na 2SeO 3-RNA. RNA aggregations occurred at higher selenium concentrations. No biopolymer conformational changes were observed upon Na 2SeO 4 and Na 2SeO 3 interactions, while RNA remains in the A-family structure.

  16. Growth mechanism of NaClO3 and NaBrO3 crystals from aqueous ...

    Indian Academy of Sciences (India)

    Unknown

    tamura (1978) developed a sophisticated apparatus for in situ observation and studied the growth of NaClO3 crys- tals. Tsukamoto and Sunagawa (1990) made a systematic study of the growth of KCl in the presence of Pb ions. Though we have reported studies on growth of NaClO3 and NaBrO3 crystals, they were largely ...

  17. Anisotropy and polarization in charge changing collisions of C4+ with Na(3s) and laser aligned Na(3p)

    NARCIS (Netherlands)

    Hoekstra, R; Morgenstern, R; Olson, RE

    1996-01-01

    Absolute cross sections for C3+(6-->5) emission at 465.7 nm after collisions of C4+ ions with ground state Na(3s) and laser excited aligned Na(Sp) atoms are measured over the collision energy range of 3-7 keV amu(-1). For Na(3s) polarizations are observed by measuring the linear polarization of the

  18. Crystal structure of polyphosphates NaCd(PO3)3 and NaMn(PO3)3

    International Nuclear Information System (INIS)

    Murashova, E.V.; Chudinova, N.N.

    1997-01-01

    Crystal structure of NaCd(PO 3 ) 3 (1) and NaMn(PO 3 ) 3 (2) isostructural polyphosphates was determined for twin samples. Rhombic lattice parameters of (1): a = 14.678, b = 14.669, c = 14.705 A, sp. gr. P2 1 2 1 2 1 , Z = 16. The structure of compounds is of frame type. Polyphosphate chain with repetition period of 24 PO 4 tetrahedrons contacts with NaO 6 and M 2 O 6 octahedrons by means of common oxygen vertices. Similarities and differences in structure of mentioned polyphosphates and earlier analyzed NaMg(PO 3 ) 3 polyphosphate are noted [ru

  19. 43. Calmodulin regulating calcium sensitivity of Na channels

    Directory of Open Access Journals (Sweden)

    R. Vegiraju

    2016-07-01

    Full Text Available By extrapolating information from existing research and observing previous assumptions regarding the structure of the Na Channel, this experiment was conducted under the hypothesis that the Na Channel is in part regulated by the calmodulin protein, as a result proving calcium sensitivity of the Na Channel. Furthermore, we assume that there is a one to one stoichiometry between the Na Channel and the Calmodulin. There has been extensive research into the functionality and structure of sodium ion channels (Na channels, as several diseases are associated with the lack of regulation of sodium ions, that is caused by the disfunction of these Na channels. However, one highly controversial matter in the field is the importance of the protein calmodulin (CaM and calcium in Na channel function. Calmodulin is a protein that is well known for its role as a calcium binding messenger protein, and that association is believed to play an indirect role in regulating the Na channel through the Na channel’s supposed calcium sensitivity. While there are proponents for both sides, there has been relatively little research that provides strong evidence for either case. In this experiment, the effect of calmodulin on NaV 1.5 is tested by preparing a set of cardiac cells (of the human specie with the NaV 1.5 C-Termini and CaM protein, which were then to be placed in solutions with varying concentrations of calcium. We took special care to test multiple concentrations of calcium, as previous studies have tested very low concentrations, with Manu Ben-Johny’s team from the John Hopkins laboratory in particular testing up to a meager 50 micromolar, despite producing a well-respected paper (By comparison, the average Na channel can naturally sustain a concentration of almost 1-2 millimolar and on some occasions, reaching even higher concentrations. After using light scattering and observing the signals given off by the calcium interacting with these Nav1.5/Ca

  20. Estratégias na Terapêutica Transfusional na Malária e Drepanocitose

    OpenAIRE

    Barra, A

    2017-01-01

    Um mesmo mundo, diferentes realidades Apesar dos casos de malária, no mundo, terem diminuído de aproximadamente 40 milhões entre 2000 e 2015, neste último ano o número estimado de mortes por malária ainda rondou os 438.000, sendo 88% destas na região africana.(1) Em 2011 os casos de morte por malária aconteceram maioritariamente em crianças com menos de 5 anos de idade na África subsaariana.(2) As grávidas, são um grupo, com um risco aumentado de morbilidade e mortalidade, que se es...