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Sample records for jararaca serpentes viperidae

  1. Biochemical and biological characterization of the venoms of Bothriopsis bilineata and Bothriopsis taeniata (Serpentes: Viperidae).

    PubMed

    Porto, Bárbara N; Telli, Caliandra A; Dutra, Tatiana P; Alves, Letícia S; Bozza, Marcelo T; Fin, Cyntia A; Thiesen, Flavia V; Renner, Márcia F

    2007-08-01

    Snake venom is a complex mixture containing diverse protein components with different structures and functions that are used for prey immobilization and death. Snake venoms from the family Viperidae cause pronounced local and systemic effects, such as pain, edema, hemorrhage and necrosis. Here, we investigated the enzymatic and biological activities of venoms from two Amazonian snakes, Bothriopsis bilineata and Bothriopsis taeniata. Both venoms presented high enzymatic activities for proteases kallikrein, thrombin and plasmin, low levels of trypsin, cathepsin C and leucine aminopeptidase activities, while lacked acetylcholinesterase activity. B. taeniata and B. bilineata crude venoms caused inflammation inducing neutrophil recruitment into peritoneal cavity of mice 4h after injection. Neutrophil recruitment induced by B. taeniata venom was accompanied by hemorrhage. EDTA treatment profoundly impaired neutrophil recruitment, suggesting the involvement of a metalloproteinase on venoms-induced neutrophil recruitment. Pretreatment with dexamethasone and zileuton, a 5-lipoxygenase inhibitor, significantly reduced neutrophil migration, but indomethacin and montelukast, a cysteinyl leukotriene receptor antagonist, had no effect, suggesting the involvement of lipoxygenase-derived metabolites, probably LTB(4). Together, these results show that B. bilineata and B. taeniata venoms induce a marked inflammatory reaction, with leukocyte recruitment, and hemorrhage, which parallels to a high proteolytic activity found in these venoms. PMID:17537475

  2. The genus Atheris (Serpentes: Viperidae) in East Africa: phylogeny and the role of rifting and climate in shaping the current pattern of species diversity.

    PubMed

    Menegon, M; Loader, S P; Marsden, S J; Branch, W R; Davenport, T R B; Ursenbacher, S

    2014-10-01

    Past climatic and tectonic events are believed to have strongly influenced species diversity in the Eastern Afromontane Biodiversity Hotspot. We investigated the phylogenetic relationships and historical biogeography of the East African genus Atheris (Serpentes: Viperidae), and explored temporal and spatial relationships between Atheris species across Africa, and the impact of palaeoclimatic fluctuations and tectonic movements on cladogenesis of the genus. Using mitochondrial sequence data, the phylogeny of East African species of Atheris shows congruent temporal patterns that link diversification to major tectonic and aridification events within East Africa over the last 15million years (my). Our results are consistent with a scenario of a delayed direct west-east colonisation of the Eastern Arc Mountains of Atheris by the formation of the western rift. Based on the phylogenetic patterns, this terrestrial, forest-associated genus has dispersed into East Africa across a divided route, on both west-southeasterly and west-northeasterly directions (a C-shaped route). Cladogenesis in the Eastern Arc Mountains and Southern Highlands of Tanzania corresponds to late Miocene and Plio-Pleistocene climatic shifts. Taxonomically, our data confirmed the monophyly of Atheris as currently defined, and reveal four major East African clades, three of which occur in discrete mountain ranges. Possible cryptic taxa are identified in the Atheris rungweensis and A. ceratophora clades. PMID:24952316

  3. Annual cycle of plasma testosterone in male copperheads, Agkistrodon contortrix (Serpentes, Viperidae): relationship to timing of spermatogenesis, mating, and agonistic behavior.

    PubMed

    Schuett, G W; Harlow, H J; Rose, J D; Van Kirk, E A; Murdoch, W J

    1997-03-01

    Reproductive cycles of the majority of squamate reptiles remain undescribed. Few studies are available on seasonal patterns of circulating steroid hormones in snakes. The goal of this study was to document the annual cycle of plasma testosterone (T) in male copperheads Agkistrodon contortrix, a North American pitviper (Serpentes, Viperidae). Two experimental conditions were used in this laboratory study. One condition (repeat-test group) consisted of 10 adult males that were sampled once each month for 11 months. The other condition (single-test groups) consisted of 10 groups each with 5 males (N = 50), and each male was tested a single time. The single-test condition was used to evaluate whether or not repeated handling and sampling affected T levels. The study was conducted from February-December, 1992. A well-defined seasonal pattern of plasma T levels was detected; patterns were similar under both experimental conditions with the exception that the repeat-test group had slightly lower levels. Levels of T were lowest (baseline) in April-May, increased in early summer (June), and were highest in late summer (August). Thereafter, T levels declined up to the time of hibernation (early November) and changed little during hibernation (November-January). Upon emergence from hibernation in late winter (February), T levels increased sharply from February to March and then decreased from March to April. The results are discussed in the context of timing of spermatogenesis, mating, and male agonistic behavior. PMID:9073504

  4. The Evolutionary Implications of Hemipenial Morphology of Rattlesnake Crotalus durissus terrificus (Laurent, 1768) (Serpentes: Viperidae: Crotalinae)

    PubMed Central

    Porto, Marcovan; de Oliveira, Marco Antonio; Pissinatti, Lorenzo; Rodrigues, Renata Lopes; Rojas-Moscoso, Julio Alejandro; Cogo, José Carlos; Metze, Konradin; Antunes, Edson; Nahoum, César; Mónica, Fabíola Z.; De Nucci, Gilberto

    2013-01-01

    Most amniotes vertebrates have an intromittent organ to deliver semen. The reptile Sphenodon and most birds lost the ancestral penis and developed a cloaca-cloaca mating. Known as hemipenises, the copulatory organ of Squamata shows unique features between the amniotes intromittent organ. They are the only paired intromittent organs across amniotes and are fully inverted and encapsulated in the tail when not in use. The histology and ultrastructure of the hemipenes of Crotalus durissus rattlesnake is described as the evolutionary implications of the main features discussed. The organization of hemipenis of Crotalus durissus terrificus in two concentric corpora cavernosa is similar to other Squamata but differ markedly from the organization of the penis found in crocodilians, testudinata, birds and mammals. Based on the available data, the penis of the ancestral amniotes was made of connective tissue and the incorporation of smooth muscle in the framework of the sinusoids occurred independently in mammals and Crotalus durissus. The propulsor action of the muscle retractor penis basalis was confirmed and therefore the named should be changed to musculus hemipenis propulsor.The retractor penis magnus found in Squamata has no homology to the retractor penis of mammals, although both are responsible for the retraction of the copulatory organ. PMID:23840551

  5. Is the population of Crotalus durissus (Serpentes, Viperidae) expanding in Brazil?

    PubMed Central

    2013-01-01

    Crotalus durissus are found from Mexico to northern Argentina in a highly disjunct distribution. According to some studies, this species is prone to occupy areas disturbed by human activities and floods comprise a plausible method of dispersal as inferred for some North American rattlesnakes. Based on the literature, it seems plausible that Crotalus durissus expanded their natural distribution in Brazil due to floods, but only in a few municipalities in Rio de Janeiro State. Data entries of Butantan Institute, in São Paulo, Brazil, from 1998 to 2012 show a declining tendency of snakes brought by donors. In addition, research shows no evidence of Crotalus durissus being an expanding species in the Brazilian territory. PMID:24314146

  6. Natural history of the terciopelo Bothrops asper (Serpentes: Viperidae) in Costa Rica.

    PubMed

    Sasa, Mahmood; Wasko, Dennis K; Lamar, William W

    2009-12-01

    The terciopelo Bothrops asper is the only lancehead species widely distributed in the humid lowlands of Middle America and northwestern South America. Its large body size, relative abundance and cryptic habits contribute to the high incidence of snakebites induced by this species throughout its distribution. The terciopelo plays an important role in ecosystems, both as prey and as a generalist predator. Diet comprises a great variety of prey items, including some species that are considered nuisances. B. asper, as other lancehead species, exhibits a notable ontogenetic shift in diet, consuming ectotherms (mainly frogs and lizards) when young, and increasingly incorporating birds, rodents, and other small mammals with maturity. Adult terciopelos also consume large anurans, especially when endothermic prey availability is low. Using radiotelemetry we determined home range and movement patterns from 28 individual B. asper at La Selva Biological Station, Costa Rica. Overall home range estimates are relatively small compared with other pitvipers, averaging between 3.71ha and 5.95ha; home range size did not differ between males and females. Movement patterns are largely aseasonal and consist of short (<10 m) movements between daytime shelter and nocturnal ambush sites within a given area, interspersed with longer distance (>50 m) movements to new foraging areas. Habitat use is related to prey availability and therefore to foraging strategy. Our data support a strong preference for areas near swamps by both sexes. Reproduction in B. asper is highly seasonal, and--apparently--biannual. Reproductive cycles in Costa Rica are tightly related to rainfall patterns. Therefore, the timing of breeding differs between populations in the Caribbean and Pacific lowlands. Bothrops asper is adapted to areas with low levels of disturbance along the agricultural frontier, and consequently it is not rare to find it in or near human dwellings. However, despite popular belief, no evidence supports a purported increase in population density of this species in Costa Rica. Despite human persecution and substantial modification of habitat, B. asper is a species with a conservation status of least concern, and probably will likely persist well into the future. Thus, it is important to learn how to coexist with this species, and to improve mechanisms for the prevention and treatment of accidental snakebite and its consequences. PMID:19563822

  7. Discovery of a Novel Accessory Structure of the Pitviper Infrared Receptor Organ (Serpentes: Viperidae)

    PubMed Central

    Bolívar-G, Wilmar; Antoniazzi, Marta M.; Grant, Taran; Jared, Carlos

    2014-01-01

    The facial pits of rattlesnakes, copperheads, lanceheads, bushmasters and other American and Asian pitvipers (Crotalinae) are highly innervated and densely vascularized infrared (IR) receptor organs. For over a century, studies have focused on a small sample of model species from North America and Asia. Based on an expanded survey of Central and South American crotalines, we report a conspicuous accessory structure composed of well-defined papillae that project from the anterior orbital adnexa. The papillae are continuous with the inner chamber of the IR receptor organ and our histological and ultrastructural data suggest that they possess a well-developed nervous network and extensive vascularization; however, they lack the characteristic IR-sensitive terminal nerve masses found in the IR-receptive pit membrane. The function of the IR receptor organ papillae is unknown. PMID:24595025

  8. Ecological divergence and sexual selection drive sexual size dimorphism in New World pitvipers (Serpentes: Viperidae).

    PubMed

    Hendry, C R; Guiher, T J; Pyron, R A

    2014-04-01

    Hypotheses for the origin and maintenance of sexual size dimorphism (SSD) fall into three primary categories: (i) sexual selection on male size, (ii) fecundity selection on female size and (iii) ecological selection for gender-specific niche divergence. We investigate the impact of these forces on SSD evolution in New World pitvipers (Crotalinae). We constructed a phylogeny from up to eight genes (seven mitochondrial, one nuclear) for 104 species of NW crotalines. We gathered morphological and ecological data for 82 species for comparative analyses. There is a strong signal of sexual selection on male size driving SSD, but less evidence for fecundity selection on female size across lineages. No support was found for allometric scaling of SSD (Rensch's rule), nor for directional selection for increasing male size (the Fairbairn-Preziosi hypothesis) in NW crotalines. Interestingly, arboreal lineages experience higher rates of SSD evolution and a pronounced shift to female-biased dimorphism. This suggests that fecundity selection on arboreal females exaggerates ecologically mediated dimorphism, whereas sexual selection drives male size in terrestrial lineages. We find that increasing SSD in both directions (male- and female-biased) decreases speciation rates. In NW crotalines, it appears that increasing magnitudes of ecologically mediated SSD reduce rates of speciation, as divergence accumulates within species among sexes, reducing adaptive divergence between populations leading to speciation. PMID:24597708

  9. [Neutralization of the hemorrhagic effect induced by Bothrops asper (Serpentes: Viperidae) venom with tropical plant extracts].

    PubMed

    Castro, O; Gutiérrez, J M; Barrios, M; Castro, I; Romero, M; Umaña, E

    1999-09-01

    Organic extracts representing 48 species included in 30 families of Costa Rican tropical plants were evaluated for their ability to neutralize hemorrhagic activity induced by the venom of the snake Bothrops asper. A bioassay in mice was used, based on intradermal injection of either venom or venom-extract mixtures followed by the measurement of hemorrhagic areas. Total inhibition of hemorrhage was observed with the ethanolic, ethyl acetate and aqueous extracts of Bursera simaruba, Clusia torresii, C. palmana, Croton draco, Persea americana, Phoebe brenesii, Pimenta dioica, Sapindus saponaria, Smilax cuculmeca and Virola koschnyi. Chemical analysis of these extracts identified catequines, flavones, anthocyanines and condensated tannins, which may be responsible for the inhibitory effect observed, probably owing to the chelation of the zinc required for the catalytic activity of venom's hemorrhagic metalloproteinases. PMID:10883329

  10. Bothrops jararaca envenomation: Pathogenesis of hemostatic disturbances and intravascular hemolysis.

    PubMed

    Senise, Luana V; Yamashita, Karine M; Santoro, Marcelo L

    2015-11-01

    To attain fully functional biological activity, vitamin-K dependent coagulation factors (VKDCF) are ?-carboxylated prior to secretion from liver. Warfarin impairs the ?-carboxylation, and consequently their physiological function. Bothrops jararaca snake venom (BjV) contains several activators of blood coagulation, especially procoagulant enzymes (prothrombin and factor X activators) and thrombin-like enzymes. In order to clarify the relative contribution of prothrombin and factor X activators to the hemostatic disturbances occurring during experimental B. jararaca envenomation, warfarin was used to deplete VKDCF, prior to BjV administration. Male Wistar rats were pretreated with saline (Sal) or warfarin (War) and inoculated subsequently with BjV or saline, thus forming four groups: Sal?+?Sal (negative control), Sal?+?BjV (positive control), War?+?Sal (warfarinization control), and War?+?BjV. Three hours after inoculation, prothrombin and factor X levels fell 40% and 50%, respectively; levels of both factors decreased more than 97% in the War?+?Sal and War?+?BjV groups. Platelet counts dropped 93% and 76% in Sal?+?BjV and War?+?BjV, respectively, and plasma fibrinogen levels decreased 86% exclusively in Sal?+?BjV. After 6 and 24?h, platelet counts and fibrinogen levels increased progressively. A dramatic augmentation in plasma hemoglobin levels and the presence of schizocytes and microcytes in the Sal?+?BjV group indicated the development of intravascular hemolysis, which was prevented by warfarin pretreatment. Our findings show that intravascular thrombin generation has the foremost role in the pathogenesis of coagulopathy and intravascular hemolysis, but not in the development of thrombocytopenia, in B. jararaca envenomation in rats; in addition, fibrinogenases (metalloproteinases) may contribute to coagulopathy more than thrombin-like enzymes. PMID:26080462

  11. Agathos Daimon and the Asklepian serpent.

    PubMed

    Pearn, John

    2011-06-01

    Much conjecture abounds about the origin of the Asklepian serpent of healing, this latter the universal metonym for curative medicine. Iconographic evidence of Asklepios with his staff-entwined serpent exists from Hippocratic times. Many theories exist about the origin of this reptilian symbol of curative medicine. Speculation has ranged from the skin-shed serpent emergent in new and robust health to putative associations with earlier Egyptian and Babylonian anguine (snake) symbols of life-determining power. Other scholars have drawn attention to the Palaeolithic, Neolithic and later Bronze-Age associations with serpent veneration in the context of rain and fertility religious invocations in India; and in many other cultures. In the South Pacific, in Australia and in Central and South America, serpents were regarded as spirits of the earth, often chthonian spirits who possessed life-giving powers. In Chaldean and Arabic etymology, the words for "serpent" and "life" have a synergy. In Classical Greece, the Agathos Daimon was literally the "noble spirit", a personal companion spirit ensuing health and good fortune. The Agathos Daimon was portrayed in iconography as a serpent, or as a fit and comely youth. This paper conjectures that the serpentine Agathos Daimon was one origin of the Asklepian symbol of medicine, portrayed as the serpent associated of the Homeric Asklepios. In later Roman times, the Agathos Daimon was transliterated to the agathodaemon, a protective companion spirit both of individuals and of the homes in which they lived. This benign resident spirit featured prominently in Roman art and was a common feature as a protective household spirit in first century homes at both Pompeii and Herculaneum. The agathodaemon motif also featured on Roman coins, such as bronze diobols of Antoninus Plus (138 - 161 A.D.) from Alexandrian mints in Egypt. In the twenty-first century, the serpentine Agathos Daimon is honoured not only as the symbol of medicine; but is daily acknowledged in toasts to "Good Health". PMID:22043596

  12. Phenotypic differences in a cryptic predator: factors influencing morphological variation in the terciopelo Bothrops asper (Garman, 1884; Serpentes: Viperidae).

    PubMed

    Saldarriaga-Córdoba, Mónica María; Sasa, Mahmood; Pardo, Rodrigo; Méndez, Marco Antonio

    2009-12-01

    The terciopelo Bothrops asper, is a cryptic lancehead pitviper widely distributed in humid environments of Middle America and the north-western portion of South America. Throughout its extensive distribution range, the terciopelo exhibits great morphological variation in external characters, a situation that has complicated its proper separation from other related species. In this paper, we analyzed the phenotypic variation of B. asper based in a sample of 514 specimens from nine distinct physiographic regions. Univariate and multivariate analyses demonstrated great phenotypic differentiation among most pre-established groups, and the pattern is fairly congruent between sexes. However, no correspondence was observed between morphological variation and molecular divergence, inferred from mDNA sequences, between individuals representing the physiographical regions under study. Geographic variation in the number of interrictals, ventral scales, subcaudal scales and dorsal blotches was positively correlated with latitude and number of dry months, but inversely related with precipitation. However, other variables do not exhibit such an effect. The observed relationships between scale counts and environmental variables are explained in terms of selective pressures to improve water balance along the distributional range of the species. PMID:19505490

  13. Description of Serpentirhabdias atroxi n. sp. (Nematoda: Rhabdiasidae), a parasite of Bothrops atrox (Linnaeus) (Reptilia: Serpentes: Viperidae) in Brazilian Amazonia.

    PubMed

    Kuzmin, Yuriy; Giese, Elane Guerreiro; Melo, Francisco Tiago de Vasconcelos; da Costa, Paulo André Ferreira Borges; Maschio, Gleomar Fabiano; Santos, Jeannie Nascimento Dos

    2016-01-01

    A new lung-dwelling nematode species is described from the common lancehead Bothrops atrox (Linnaeus) in the Brazilian Amazon Region. The species is assigned to the genus Serpentirhabdias Tkach, Kuzmin & Snyder, 2014 based on the presence of six lips arranged in two lateral groups, the absence of prominent cuticular inflations, and lung parasitism in snakes. Serpentirhabdias atroxi n. sp. differs from other species of the genus mainly by details of the morphology of the anterior end: cuticularised ring surrounding the anterior part of the buccal cavity and six minute onchia present in the oesophastome. Serpentirhabdias atroxi n. sp. is the seventh species of the genus known from the Neotropical Realm and the second species described from viperid snakes. PMID:26739285

  14. Inhibitory effect of the plant Clusia fluminensis against biological activities of Bothrops jararaca snake venom.

    PubMed

    de Oliveira, Eduardo Coriolano; Anholeti, Maria Carolina; Domingos, Thaisa Francielle; Faioli, Camila Nunes; Sanchez, Eladio Flores; de Paiva, Selma Ribeiro; Fuly, André Lopes

    2014-01-01

    The ability of extracts of the plant Clusia fluminensis Planch & Triana (Clusiaceae Lindl.) to neutralize proteolysis, clotting, hemolysis, hemorrhagic and lethality activities of Bothrops jararaca snake venom was studied. Clusianone and lanosterol from the flower and fruit extracts, respectively, were also tested. The extracts of different organs of C. fluminensis inhibited proteolysis and hemolysis induced by B. jararaca venom, but with different potencies. Only the stems prevented blood clotting. Only the acetone extract of the fruit protected mice from hemorrhage while the acetone or methanol extracts prevented mice from death. Clusianone and lanosterol did not inhibit clotting or hemorrhage, but the former inhibited proteolysis and the latter hemolysis. PMID:24660453

  15. Appraisal of antiophidic potential of marine sponges against Bothrops jararaca and Lachesis muta venom.

    PubMed

    Faioli, Camila Nunes; Domingos, Thaisa Francielle Souza; de Oliveira, Eduardo Coriolano; Sanchez, Eládio Flores; Ribeiro, Suzi; Muricy, Guilherme; Fuly, Andre Lopes

    2013-10-01

    Snakebites are a health problem in many countries due to the high incidence of such accidents. Antivenom treatment has regularly been used for more than a century, however, this does not neutralize tissue damage and may even increase the severity and morbidity of accidents. Thus, it has been relevant to search for new strategies to improve antiserum therapy, and a variety of molecules from natural sources with antiophidian properties have been reported. In this paper, we analyzed the ability of ten extracts from marine sponges (Amphimedon viridis, Aplysina fulva, Chondrosia collectrix, Desmapsamma anchorata, Dysidea etheria, Hymeniacidon heliophila, Mycale angulosa, Petromica citrina, Polymastia janeirensis, and Tedania ignis) to inhibit the effects caused by Bothrops jararaca and Lachesis muta venom. All sponge extracts inhibited proteolysis and hemolysis induced by both snake venoms, except H. heliophila, which failed to inhibit any biological activity. P. citrina inhibited lethality, hemorrhage, plasma clotting, and hemolysis induced by B. jararaca or L. muta. Moreover, other sponges inhibited hemorrhage induced only by B. jararaca. We conclude that Brazilian sponges may be a useful aid in the treatment of snakebites caused by L. muta and B. jararaca and therefore have potential for the discovery of molecules with antiophidian properties. PMID:24141284

  16. Appraisal of Antiophidic Potential of Marine Sponges against Bothrops jararaca and Lachesis muta Venom

    PubMed Central

    Faioli, Camila Nunes; Domingos, Thaisa Francielle Souza; de Oliveira, Eduardo Coriolano; Sanchez, Eládio Flores; Ribeiro, Suzi; Muricy, Guilherme; Fuly, Andre Lopes

    2013-01-01

    Snakebites are a health problem in many countries due to the high incidence of such accidents. Antivenom treatment has regularly been used for more than a century, however, this does not neutralize tissue damage and may even increase the severity and morbidity of accidents. Thus, it has been relevant to search for new strategies to improve antiserum therapy, and a variety of molecules from natural sources with antiophidian properties have been reported. In this paper, we analyzed the ability of ten extracts from marine sponges (Amphimedon viridis, Aplysina fulva, Chondrosia collectrix, Desmapsamma anchorata, Dysidea etheria, Hymeniacidon heliophila, Mycale angulosa, Petromica citrina, Polymastia janeirensis, and Tedania ignis) to inhibit the effects caused by Bothrops jararaca and Lachesis muta venom. All sponge extracts inhibited proteolysis and hemolysis induced by both snake venoms, except H. heliophila, which failed to inhibit any biological activity. P. citrina inhibited lethality, hemorrhage, plasma clotting, and hemolysis induced by B. jararaca or L. muta. Moreover, other sponges inhibited hemorrhage induced only by B. jararaca. We conclude that Brazilian sponges may be a useful aid in the treatment of snakebites caused by L. muta and B. jararaca and therefore have potential for the discovery of molecules with antiophidian properties. PMID:24141284

  17. Burnup calculation methodology in the serpent 2 Monte Carlo code

    SciTech Connect

    Leppaenen, J.; Isotalo, A.

    2012-07-01

    This paper presents two topics related to the burnup calculation capabilities in the Serpent 2 Monte Carlo code: advanced time-integration methods and improved memory management, accomplished by the use of different optimization modes. The development of the introduced methods is an important part of re-writing the Serpent source code, carried out for the purpose of extending the burnup calculation capabilities from 2D assembly-level calculations to large 3D reactor-scale problems. The progress is demonstrated by repeating a PWR test case, originally carried out in 2009 for the validation of the newly-implemented burnup calculation routines in Serpent 1. (authors)

  18. A Transcriptomic View of the Proteome Variability of Newborn and Adult Bothrops jararaca Snake Venoms

    PubMed Central

    Zelanis, André; Andrade-Silva, Débora; Rocha, Marisa M.; Furtado, Maria F.; Serrano, Solange M. T.; Junqueira-de-Azevedo, Inácio L. M.; Ho, Paulo Lee

    2012-01-01

    Background Snake bite is a neglected public health problem in communities in rural areas of several countries. Bothrops jararaca causes many snake bites in Brazil and previous studies have demonstrated that the pharmacological activities displayed by its venom undergo a significant ontogenetic shift. Similarly, the venom proteome of B. jararaca exhibits a considerable variation upon neonate to adult transition, which is associated with changes in diet from ectothermic prey in early life to endothermic prey in adulthood. Moreover, it has been shown that the Brazilian commercial antibothropic antivenom, which is produced by immunization with adult venom, is less effective in neutralizing newborn venom effects. On the other hand, venom gland transcripts of newborn snakes are poorly known since all transcriptomic studies have been carried out using mRNA from adult specimens. Methods/Principal Findings Here we analyzed venom gland cDNA libraries of newborn and adult B. jararaca in order to evaluate whether the variability demonstrated for its venom proteome and pharmacological activities was correlated with differences in the structure of toxin transcripts. The analysis revealed that the variability in B. jararaca venom gland transcriptomes is quantitative, as illustrated by the very high content of metalloproteinases in the newborn venom glands. Moreover, the variability is also characterized by the structural diversity of SVMP precursors found in newborn and adult transcriptomes. In the adult transcriptome, however, the content of metalloproteinase precursors considerably diminishes and the number of transcripts of serine proteinases, C-type lectins and bradykinin-potentiating peptides increase. Moreover, the comparison of the content of ESTs encoding toxins in adult male and female venom glands showed some gender-related differences. Conclusions/Significance We demonstrate a substantial shift in toxin transcripts upon snake development and a marked decrease in the metalloproteinase P-III/P-I class ratio which are correlated with changes in the venom proteome complexity and pharmacological activities. PMID:22428077

  19. Kallikrein-kinin system in the plasma of the snake Bothrops jararaca.

    PubMed Central

    Abdalla, F. M.; Hiraichi, E.; Picarelli, Z. P.; Prezoto, B. C.

    1989-01-01

    1. Bothrops jararaca venom (BJV) caused a fall in the carotid artery blood pressure of the anaesthetized snake. This effect was tachyphylactic and was potentiated by captopril, a kininase II inhibitor; it was partially antagonized by promethazine plus cimetidine and was not affected by atropine. 2. Similar hypotensive effects were obtained by administration of trypsin or a partially purified BJV kininogenase to the snake. 3. Incubation of Bothrops jararaca plasma (BJP) with trypsin released a substance (or substances) that produced hypotension in the snake but not in the rat; this hypotensive effect was also potentiated by captopril. 4. The trypsinised plasma contracted Bothrops jararaca isolated uterus, a pharmacological preparation weakly sensitive to bradykinin. Trypsinised plasma was inactive on pigeon oviduct and rat uterus and displayed a weak action on the guinea-pig ileum. Similar effects were observed with incubates of a fraction of BJP, containing globulins, with a partially purified BJV kininogenase. 5. Like mammalian kinins, the substance(s) was(were) dialysable, thermostable in acid but not in alkaline pH, and inactivated by chymotrypsin but not by trypsin. Its(their) inactivation by BJP or BJP kininase II was inhibited by captopril. 6. These findings strongly suggest that, besides releasing histamine, BJV or trypsin release a kininlike substance (or substances) from the snake plasma. 7. Since BJV and other kininogenases active on mammalian plasma were shown to be unable to release kinins from BJP, in experiments conducted on pharmacological preparations suitable for the assay of mammalian kinins, these data also suggest that the snake Bothrops jararaca, like birds, may have developed its own kallikrein-kinin system. PMID:2804549

  20. Proteomic Analysis of the Ontogenetic Variability in Plasma Composition of Juvenile and Adult Bothrops jararaca Snakes

    PubMed Central

    de Morais-Zani, Karen; Grego, Kathleen Fernandes; Tanaka, Aparecida Sadae; Tanaka-Azevedo, Anita Mitico

    2013-01-01

    The ontogenetic variability in venom composition of some snake genera, including Bothrops, as well as the biological implications of such variability and the search of new molecules that can neutralize the toxic components of these venoms have been the subject of many studies. Thus, considering the resistance of Bothrops jararaca to the toxic action of its own venom and the ontogenetic variability in venom composition described in this species, a comparative study of the plasma composition of juvenile and adult B. jararaca snakes was performed through a proteomic approach based on 2D electrophoresis and mass spectrometry, which allowed the identification of proteins that might be present at different levels during ontogenetic development. Among the proteins identified by mass spectrometry, antihemorrhagic factor Bj46a was found only in adult plasma. Moreover, two spots identified as phospholipase A2 inhibitors were significantly increased in juvenile plasma, which can be related to the higher catalytic PLA2 activity shown by juvenile venom in comparison to that of adult snakes. This work shows the ontogenetic variability of B. jararaca plasma, and that these changes can be related to the ontogenetic variability described in its venom. PMID:24062950

  1. Comparative Analysis of Viperidae Venoms Antibacterial Profile: a Short Communication for Proteomics

    PubMed Central

    Ferreira, Bruno L.; Santos, Dilvani O.; dos Santos, André Luis; Rodrigues, Carlos R.; de Freitas, Cícero C.; Cabral, Lúcio M.; Castro, Helena C.

    2011-01-01

    Bacterial infections involving multidrug-resistant strains are one of the ten leading causes of death and an important health problem in need for new antibacterial sources and agents. Herein, we tested and compared four snake venoms (Agkistrodon rhodostoma, Bothrops jararaca, B. atrox and Lachesis muta) against 10 Gram-positive and Gram-negative drug-resistant clinical bacteria strains to identify them as new sources of potential antibacterial molecules. Our data revealed that, as efficient as some antibiotics currently on the market (minimal inhibitory concentration (MIC) = 1–32 ?g mL?1), A. rhodostoma and B. atrox venoms were active against Staphylococcus epidermidis and Enterococcus faecalis (MIC = 4.5 ?g mL?1), while B. jararaca inhibited S. aureus growth (MIC = 13 ?g ml?1). As genomic and proteomic technologies are improving and developing rapidly, our results suggested that A. rhodostoma, B. atrox and B. jararaca venoms and glands are feasible sources for searching antimicrobial prototypes for future design new antibiotics against drug-resistant clinical bacteria. They also point to an additional perspective to fully identify the pharmacological potential of these venoms by using different techniques. PMID:18955360

  2. Antigenic, microbicidal and antiparasitic properties of an l-amino acid oxidase isolated from Bothrops jararaca snake venom.

    PubMed

    Ciscotto, P; Machado de Avila, R A; Coelho, E A F; Oliveira, J; Diniz, C G; Farías, L M; de Carvalho, M A R; Maria, W S; Sanchez, E F; Borges, A; Chávez-Olórtegui, C

    2009-03-01

    Venoms from the bee Apis mellifera, the caterpillar Lonomia achelous, the spiders Lycosa sp. and Phoneutria nigriventer, the scorpions Tityus bahiensis and Tityus serrulatus, and the snakes Bothrops alternatus, Bothrops jararaca, Bothrops jararacussu, Bothrops moojeni, Bothrops neuwiedi, Crotalus durissus terrificus, and Lachesis muta were assayed (800mug/mL) for activity against Staphylococcus aureus. Venoms from B. jararaca and B. jararacussu showed the highest S. aureus growth inhibition and also against other Gram-positive and Gram-negative bacteria. To characterize the microbicidal component(s) produced by B. jararaca, venom was fractionated through gel exclusion chromatography. The high molecular weight, anti-S. aureus P1 fraction was further resolved by anion exchange chromatography through Mono Q columns using a 0-0.5M NaCl gradient. Bactericidal Mono Q fractions P5 and P6 showed significant LAAO activity using l-leucine as substrate. These fractions were pooled and subjected to Heparin affinity chromatography, which rendered a single LAAO activity peak. The anti-S. aureus activity was abolished by catalase, suggesting that the effect is dependent on H(2)O(2) production. SDS-PAGE of isolated LAAO indicated the presence of three isoforms since deglycosylation with a recombinant N-glycanase rendered a single 38.2 kDa component. B. jararaca LAAO specific activity was 142.7 U/mg, based on the oxidation of l-leucine. The correlation between in vivo neutralization of lethal toxicity (ED(50)) and levels of horse therapeutic antibodies anti-LAAO measured by ELISA was investigated to predict the potency of Brazilian antibothropic antivenoms. Six horses were hyperimmunized with Bothrops venoms (50% from B. jararaca and 12.5% each from B. alternatus, B. jararacussu, B. neuwiedii and B. moojeni). To set up an indirect ELISA, B. jararaca LAAO and crude venom were used as antigens. Correlation coefficients (r) between ED(50) and ELISA antibody titers against B. jararaca venom and LAAO were 0.846 (p<0.001) and 0.747 (p<0.001), respectively. The hemolytic and leishmanicidal (anti-Leishmania amazonensis) activity of LAAO was also determined. PMID:19101583

  3. Using SERPENT Monte Carlo and Burnup code to model Traveling Wave Reactors (TWR)

    NASA Astrophysics Data System (ADS)

    Gulik, Volodymyr; Pavlovych, Volodymyr; Tkaczyk, Alan Henry

    2014-06-01

    This paper is mainly devoted to the proof-of-principle implementation of the SERPENT code for the simulation of traveling wave reactors. The investigation of SERPENT 1.1.19 code for multiprocessor tasks with long burnup steps was performed. The investigation of SERPENT 2 code for multiprocessor tasks with long burnup steps was performed. Methods to remove the influence of the ignition zone were considered, and neutronics simulations with various fragmentations of the burnup zone were performed.

  4. Generation of SFR few-group constants using the Monte Carlo code Serpent

    SciTech Connect

    Fridman, E.; Rachamin, R.; Shwageraus, E.

    2013-07-01

    In this study, the Serpent Monte Carlo code was used as a tool for preparation of homogenized few-group cross sections for the nodal diffusion analysis of Sodium cooled Fast Reactor (SFR) cores. Few-group constants for two reference SFR cores were generated by Serpent and then employed by nodal diffusion code DYN3D in 2D full core calculations. The DYN3D results were verified against the references full core Serpent Monte Carlo solutions. A good agreement between the reference Monte Carlo and nodal diffusion results was observed demonstrating the feasibility of using Serpent for generation of few-group constants for the deterministic SFR analysis. (authors)

  5. Ancient scientific basis of the "great serpent" from historical evidence.

    PubMed

    Stothers, Richard B

    2004-06-01

    Zoological data and a growing mythology contributed to ancient Western knowledge about large serpents. Yet little modern attention has been paid to the sources, transmission, and receipt in the early Middle Ages of the ancients' information concerning "dragons" and "sea serpents." Real animals--primarily pythons and whales--lie behind the ancient stories. Other animals, conflations of different animals, simple misunderstandings, and willful exaggerations are found to account for the fanciful embellishments, but primitive myths played no significant role in this process during classical times. The expedition of Alexander the Great into India (327-325 B.C.) and the Bagradas River incident in North Africa (256 B.C.) had enormous repercussions on the development of serpent lore. Credible evidence is found for the presence of ancient populations of pythons living along the North African coast west of Egypt and along the coast of the Arabian Sea between the Indus River and the Strait of Hormuz--places where they no longer exist today. The maximum sizes of ancient pythons may have been greater than those of today's specimens. PMID:15490966

  6. Ancient scientific basis of the "great serpent" from historical evidence

    NASA Technical Reports Server (NTRS)

    Stothers, Richard B.

    2004-01-01

    Zoological data and a growing mythology contributed to ancient Western knowledge about large serpents. Yet little modern attention has been paid to the sources, transmission, and receipt in the early Middle Ages of the ancients' information concerning "dragons" and "sea serpents." Real animals--primarily pythons and whales--lie behind the ancient stories. Other animals, conflations of different animals, simple misunderstandings, and willful exaggerations are found to account for the fanciful embellishments, but primitive myths played no significant role in this process during classical times. The expedition of Alexander the Great into India (327-325 B.C.) and the Bagradas River incident in North Africa (256 B.C.) had enormous repercussions on the development of serpent lore. Credible evidence is found for the presence of ancient populations of pythons living along the North African coast west of Egypt and along the coast of the Arabian Sea between the Indus River and the Strait of Hormuz--places where they no longer exist today. The maximum sizes of ancient pythons may have been greater than those of today's specimens.

  7. Proteoforms of the platelet-aggregating enzyme PA-BJ, a serine proteinase from Bothrops jararaca venom.

    PubMed

    Yamashiro, Edson T; Oliveira, Ana K; Kitano, Eduardo S; Menezes, Milene C; Junqueira-de-Azevedo, Inácio L; Paes Leme, Adriana F; Serrano, Solange M T

    2014-09-18

    Snake venoms contain serine proteinases that are functionally similar to thrombin and specifically cleave fibrinogen to convert it into fibrin or activate platelets to aggregation. PA-BJ is a serine proteinase from Bothrops jararaca venom that promotes platelet aggregation and this effect is mediated by the G-coupled protein receptors PAR1 and PAR4. In this study we describe an improved procedure to obtain PA-BJ from B. jararaca venom that uses less chromatographic steps, and, interestingly, results in the isolation of eight proteoforms showing slightly different pIs and molecular masses due to variations in their glycosylation levels. The identity of the isolated PA-BJ forms (1-8) was confirmed by mass spectrometry, and they showed similar platelet-activating activity on washed platelet suspensions. N- and O-deglycosylation of PA-BJ 1-8 under denaturing conditions generated variable electrophoretic profiles and showed that some forms were resistant to complete deglycosylation. Furthermore, N- and O-deglycosylation under non-denaturing conditions also showed different electrophoretic profiles between the PA-BJ forms and caused partial loss of their ability to cleave a recombinant exodomain of PAR1 receptor. In parallel, three cDNAs encoding PA-BJ-like enzymes were identified by pyrosequencing of a B. jararaca venom gland library constructed with RNA from a single specimen. Taken together, our results suggest that PA-BJ occurs in the B. jararaca venom in multiple proteoforms displaying similar properties upon platelets regardless of their variable isoelectric points, molecular masses, carbohydrate moieties and susceptibility to the activity of glycosidases, and highlight that variability of specific venom components contributes to venom proteome complexity. PMID:25239612

  8. Effects of neutrophil depletion in the local pathological alterations and muscle regeneration in mice injected with Bothrops jararaca snake venom

    PubMed Central

    Teixeira, Catarina F P; Chaves, Fernando; Zamunér, Stella R; Fernandes, Cristina M; Zuliani, Juliana P; Cruz-Hofling, María Alice; Fernandes, Irene; Gutiérrez, José María

    2005-01-01

    In order to study the role of neutrophils in the acute local pathological alterations induced by Bothrops jararaca snake venom, and in the process of skeletal muscle regeneration that follows, an experimental model was developed in mice pretreated with either an anti-mouse granulocyte rat monoclonal immunoglobulin G, which induces a profound neutropenia, or an isotype-matched control antibody. B. jararaca venom induced prominent haemorrhage and oedema, but only a moderate myonecrosis. No significant differences were observed in the extent of local haemorrhage, oedema and myonecrosis between neutropenic and control mice, suggesting that neutrophils do not play a determinant role in the acute pathological alterations induced by B. jararaca venom in this experimental model. Moreover, no differences were observed in skeletal muscle regeneration between these two experimental groups. In both the cases, limited areas of myonecrosis were associated with a drastic damage to the microvasculature and a scarce inflammatory infiltrate, with the consequent lack of removal of necrotic debris during the first week, resulting in a poor regenerative response at this time interval. Subsequently, a similar regenerative process occurred in both groups, and by 30 days, necrotic areas were substituted by groups of small regenerating muscle fibres. It is suggested that the drastic effect exerted by B. jararaca venom in the microvasculature precludes an effective access of inflammatory cells to necrotic areas, thereby compromising an effective removal of necrotic debris; this explains the poor regenerative response observed during the first week and the fact that there were no differences between neutropenic and control mice. As neutropenia in this model lasted only 7 days, the successful regenerative process observed at 30 days is associated with revascularization of necrotic regions and with a successful removal by phagocytes of necrotic debris in both groups. PMID:15810982

  9. Combined venomics, venom gland transcriptomics, bioactivities, and antivenomics of two Bothrops jararaca populations from geographic isolated regions within the Brazilian Atlantic rainforest.

    PubMed

    Gonçalves-Machado, Larissa; Pla, Davinia; Sanz, Libia; Jorge, Roberta Jeane B; Leitão-De-Araújo, Moema; Alves, Maria Lúcia M; Alvares, Diego Janisch; De Miranda, Joari; Nowatzki, Jenifer; de Morais-Zani, Karen; Fernandes, Wilson; Tanaka-Azevedo, Anita Mitico; Fernández, Julián; Zingali, Russolina B; Gutiérrez, José María; Corrêa-Netto, Carlos; Calvete, Juan J

    2016-03-01

    Bothrops jararaca is a slender and semi-arboreal medically relevant pit viper species endemic to tropical and subtropical forests in southern Brazil, Paraguay, and northern Argentina (Misiones). Within its geographic range, it is often abundant and is an important cause of snakebite. Although no subspecies are currently recognized, geographic analyses have revealed the existence of two well-supported B. jararaca clades that diverged during the Pliocene ~3.8Mya and currently display a southeastern (SE) and a southern (S) Atlantic rainforest (Mata Atlântica) distribution. The spectrum, geographic variability, and ontogenetic changes of the venom proteomes of snakes from these two B. jararaca phylogroups were investigated applying a combined venom gland transcriptomic and venomic analysis. Comparisons of the venom proteomes and transcriptomes of B. jararaca from the SE and S geographic regions revealed notable interpopulational variability that may be due to the different levels of population-specific transcriptional regulation, including, in the case of the southern population, a marked ontogenetic venom compositional change involving the upregulation of the myotoxic PLA2 homolog, bothropstoxin-I. This population-specific marker can be used to estimate the proportion of venom from the southern population present in the B. jararaca venom pool used for the Brazilian soro antibotrópico (SAB) antivenom production. On the other hand, the southeastern population-specific D49-PLA2 molecules, BinTX-I and BinTX-II, lend support to the notion that the mainland ancestor of Bothrops insularis was originated within the same population that gave rise to the current SE B. jararaca phylogroup, and that this insular species endemic to Queimada Grande Island (Brazil) expresses a pedomorphic venom phenotype. Mirroring their compositional divergence, the two geographic B. jararaca venom pools showed distinct bioactivity profiles. However, the SAB antivenom manufactured in Vital Brazil Institute neutralized the lethal effect of both venoms to a similar extent. In addition, immobilized SAB antivenom immunocaptured most of the venom components of the venoms of both B. jararaca populations, but did not show immunoreactivity against vasoactive peptides. The Costa Rican bothropic-crotalic-lachesic (BCL) antivenom showed the same lack of reactivity against vasoactive peptides but, in addition, was less efficient immunocapturing PI- and PIII-SVMPs from the SE venom, and bothropstoxin-I, a CRISP molecule, and a D49-PLA2 from the venom of the southern B. jararaca phylogroup. The remarkable paraspecificity exhibited by the Brazilian and the Costa Rican antivenoms indicates large immunoreactive epitope conservation across the natural history of Bothrops, a genus that has its roots in the middle Miocene. This article is part of a Special Issue entitled: Omics Evolutionary Ecolog. PMID:25968638

  10. Effect of diterpenes isolated of the marine alga Canistrocarpus cervicornis against some toxic effects of the venom of the bothrops jararaca snake.

    PubMed

    Domingos, Thaisa Francielle Souza; Vallim, Magui Aparecida; Cavalcanti, Diana Negrão; Sanchez, Eládio Flores; Teixeira, Valéria Laneuville; Fuly, André Lopes

    2015-01-01

    Snake venoms are composed of a complex mixture of active proteins and peptides which induce a wide range of toxic effects. Envenomation by Bothrops jararaca venom results in hemorrhage, edema, pain, tissue necrosis and hemolysis. In this work, the effect of a mixture of two secodolastane diterpenes (linearol/isolinearol), previously isolated from the Brazilian marine brown alga, Canistrocarpus cervicornis, was evaluated against some of the toxic effects induced by B. jararaca venom. The mixture of diterpenes was dissolved in dimethylsulfoxide and incubated with venom for 30 min at room temperature, and then several in vivo (hemorrhage, edema and lethality) and in vitro (hemolysis, plasma clotting and proteolysis) assays were performed. The diterpenes inhibited hemolysis, proteolysis and hemorrhage, but failed to inhibit clotting and edema induced by B. jararaca venom. Moreover, diterpenes partially protected mice from lethality caused by B. jararaca venom. The search for natural inhibitors of B. jararaca venom in C. cervicornis algae is a relevant subject, since seaweeds are a rich and powerful source of active molecules which are as yet but poorly explored. Our results suggest that these diterpenes have the potential to be used against Bothropic envenomation accidents or to improve traditional treatments for snake bites. PMID:25699595

  11. Purification and characterization of a novel peptide with antifungal activity from Bothrops jararaca venom.

    PubMed

    Gomes, V M; Carvalho, A O; Da Cunha, M; Keller, M N; Bloch, C; Deolindo, P; Alves, E W

    2005-06-01

    Different peptides have been isolated from a wide range of animal species. It is has become increasingly clear that due to the development of antibiotic-resistant microbes, antibacterial and antifungal peptides have attracted the attention in recent years, in order to find new therapeutic agents. In this work, a novel peptide with high inhibitory activity against fungi growth have been isolated from the venom of the Brazilian snake Bothrops jararaca. A Sephacryl S-100 gel filtration column was employed for further separation of proteins. The FV fraction with high antifungal activity was named Pep5Bj, pooled and submitted to reverse-phase chromatography in HPLC. The fraction containing the isolated peptide inhibited the growth of different phytopathogenic fungi (Fusarium oxysporum and Colletotrichum lindemuthianum) and yeast (Candida albicans and Saccharomyces cerevisiae). The peptide minimal inhibitory concentration is comparable to other known antifungal peptides, like insect defensins and cecropins, found in the last years in a large diversity of animals. We investigate F. oxysporum cells membrane permeabilization using SYTOX Green uptake, an organic compound that fluoresces upon interaction with nucleic acids after penetration in cell with compromised plasma membranes. When viewed under fluorescence optical microscopy, F. oxysporum cells exposed to Pep5Bj display strong SYTOX Green fluorescence in the cytosol, especially in the nuclei. The SYTOX Green data suggested that this effect is related to membrane permeabilization. The molecular masses of this peptide was obtained by MALDI-TOF spectrometry and corresponded to 1370Da. PMID:15904677

  12. Hypothalamic activity during altered salt and water balance in the snake Bothrops jararaca.

    PubMed

    Zambotti-Villela, Leonardo; Marinho, Camila Eduardo; Alponti, Rafaela Fadoni; Silveira, Paulo Flavio

    2008-01-01

    The effects of water and salt overload on the activities of the supraoptic and paraventricular nuclei and the adjacent periventricular zone of the hypothalamus of the snake Bothrops jararaca were investigated by measurements of Fos-like immunoreactivity (Fos-ir). Both water and salt overload resulted in changes in body mass, plasma osmolality, and plasma concentrations of sodium, potassium, and chloride. Hyper-osmolality increased Fos immunoreactivity in the rostral supraoptic nucleus (SON), the paraventricular nucleus (PVN), and adjacent periventricular areas. Both hyper- and hypo-osmolality increased Fos immunoreactivity in the intermediate SON, but not in other areas of the hypothalamus. Immunostaining was abundant in cerebrospinal fluid (CSF)-contacting tanycyte-like cells in the ependymal layer of the third ventricle. These data highlight some features of regional distribution of Fos immunoreactivity that are consistent with vasotocin functioning as a hormone, and support the role of hypothalamic structures in the response to disruption of salt and water balance in this snake. PMID:17703311

  13. Spectroscopic studies of stratum corneum model membrane from Bothrops jararaca treated with cationic surfactant.

    PubMed

    Baby, André Rolim; Lacerda, Aurea Cristina Lemos; Velasco, Maria Valéria Robles; Lopes, Patrícia Santos; Kawano, Yoshio; Kaneko, Telma Mary

    2006-06-01

    This research employed FT-Raman and PAS-FTIR spectroscopic techniques to evaluate the interaction of cetyl trimethyl ammonium chloride (CTAC), a cationic surfactant, on the stratum corneum (SC) of shed snake skins from Bothrops jararaca, used as model membranes. Surfactant aqueous solutions (50.0 and 0.78 gl(-1)) with neutral pH were applied on the samples with intervals of 4, 8 (whole SC) and 12h (SC tape-stripped). Samples presented modifications of the topography for all conditions of the assays and the monomers of the surfactant, instead of the micelles, seemed to interact with the keratin. The SC model membranes treated with CTAC have had an augment of water content (except for whole SC treated for 8h) indicated by the expansion of the band 3600-3300 cm(-1), mainly for the tape-stripped samples after 12h treatment. Concentration appeared to be an important factor related to an increase of the tissue hydration. PMID:16725316

  14. Two-Dimensional NMR of Velocity Exchange: VEXSY and SERPENT

    NASA Astrophysics Data System (ADS)

    Blümich, B.; Callaghan, P. T.; Damion, R. A.; Han, S.; Khrapitchev, A. A.; Packer, K. J.; Stapf, S.

    2001-09-01

    Two different multidimensional pulsed field gradient sequences are compared which have the purpose of correlating spin displacements in different time intervals with each other. The simplest possible sequence, three-pulse SERPENT, measures displacements in two interleaved time intervals, while in VEXSY, consisting of two independent pairs of gradient pulses separated by a mixing time, displacements during the two encoding intervals are compared to each other. The formalism for both sequences is discussed in q space and in displacement space and common features as well as differences between the two types of experiments are highlighted, employing the particular case of the concurrent VEXSY scheme which allows treatment according to both formalisms.

  15. Morphological study of Ophidascaris excavata Hsü & Hoeppli, 1931 (Ascaridida: Ascarididae) from Gloydius brevicaudus (Stejneger) (Reptilia: Viperidae).

    PubMed

    Li, Liang; Zhao, Wen-Ting; Chen, Hui-Xia; Guo, Yan-Ning; Zhang, Lu-Ping

    2016-01-01

    Ophidascaris excavata Hsü & Hoeppli, 1931 is a poorly known ascaridid parasite reported from the short-tailed pit viper Gloydius brevicaudus (Stejneger) (Reptilia: Viperidae) in China. In the present paper, the detailed morphology of this nematode was studied using light and scanning electron microscopy (SEM) based on newly collected material. The results revealed several important, but previously unreported, morphological features, including the presence of one pair of small, finger-like prolongations on each lip, narrow cervical alae beginning well posterior to the base of the ventrolateral lips and the second pair of postcloacal ventro-lateral papillae being double; in addition, there is no intestinal caecum. These supplementary morphological and morphometric data, especially the detailed morphological features obtained herein under SEM, would help us to understand the relationships of O. excavata with its congeners and enable us to diagnose this species more accurately. PMID:26739288

  16. Interpolations of nuclide-specific scattering kernels generated with Serpent

    SciTech Connect

    Scopatz, A.; Schneider, E.

    2012-07-01

    The neutron group-to-group scattering cross section is an essential input parameter for any multi-energy group physics model. However, if the analyst prefers to use Monte Carlo transport to generate group constants this data is difficult to obtain for a single species of a material. Here, the Monte Carlo code Serpent was modified to return the group transfer probabilities on a per-nuclide basis. This ability is demonstrated in conjunction with an essential physics reactor model where cross section perturbations are used to dynamically generate reactor state dependent group constants via interpolation from pre-computed libraries. The modified version of Serpent was therefore verified with three interpolation cases designed to test the resilience of the interpolation scheme to changes in intra-group fluxes. For most species, interpolation resulted in errors of less than 5% of transport-computed values. For important scatterers, such as {sup 1}H, errors less than 2% were observed. For nuclides with high errors ( > 10%), the scattering channel typically only had a small probability of occurring. (authors)

  17. The Serpent Monte Carlo Code: Status, Development and Applications in 2013

    NASA Astrophysics Data System (ADS)

    Leppänen, Jaakko; Pusa, Maria; Viitanen, Tuomas; Valtavirta, Ville; Kaltiaisenaho, Toni

    2014-06-01

    The Serpent Monte Carlo reactor physics burnup calculation code has been developed at VTT Technical Research Centre of Finland since 2004, and is currently used in 100 universities and research organizations around the world. This paper presents the brief history of the project, together with the currently available methods and capabilities and plans for future work. Typical user applications are introduced in the form of a summary review on Serpent-related publications over the past few years.

  18. Comparison of SERPENT and CASMO-5M for pressurized water reactors models

    SciTech Connect

    Hursin, M.; Vasiliev, A.; Ferroukhi, H.; Pautz, A.

    2013-07-01

    The objective of this work is to perform a preliminary assessment of the capability of SERPENT to generate cross sections for a PWR Beginning-of-Life (BOL) isothermal mini-core by comparing a SERPENT/PARCS solution with the results obtained using a CASMO-5M/PARCS approach. The PARCS code is used instead of the usual SIMULATE-3 to analyze the Swiss Reactors, because interfaces with PARCS already exist to obtain neutronic data from SERPENT. For the PWR configurations, the differences between CASMO-5M and SERPENT solutions are within 200 pcm at the assembly level and thus rather small when considering the deterministic transport method (energy/angular/space discretization) in CASMO-5M versus the stochastic treatment of SERPENT, the statistical uncertainties in the Monte-Carlo approach as well as the eventual differences in nuclear data used by both codes. At the 2D mini-core level, no major difference is observed when comparing PARCS run with CASMO-5M versus SERPENT cross sections. For the generation of kinetic parameters, non trivial differences are observed due both to the methods and the data used. For the relatively limited number of configurations considered, it is hard to make any definitive statement on the benefits of using Monte Carlo codes in terms of nuclear data generation. (authors)

  19. Bothrops jararaca Venom Metalloproteinases Are Essential for Coagulopathy and Increase Plasma Tissue Factor Levels during Envenomation

    PubMed Central

    Yamashita, Karine M.; Alves, André F.; Barbaro, Katia C.; Santoro, Marcelo L.

    2014-01-01

    Background/Aims Bleeding tendency, coagulopathy and platelet disorders are recurrent manifestations in snakebites occurring worldwide. We reasoned that by damaging tissues and/or activating cells at the site of the bite and systemically, snake venom toxins might release or decrypt tissue factor (TF), resulting in activation of blood coagulation and aggravation of the bleeding tendency. Thus, we addressed (a) whether TF and protein disulfide isomerase (PDI), an oxireductase involved in TF encryption/decryption, were altered in experimental snake envenomation; (b) the involvement and significance of snake venom metalloproteinases (SVMP) and serine proteinases (SVSP) to hemostatic disturbances. Methods/Principal Findings Crude Bothrops jararaca venom (BjV) was preincubated with Na2-EDTA or AEBSF, which are inhibitors of SVMP and SVSP, respectively, and injected subcutaneously or intravenously into rats to analyze the contribution of local lesion to the development of hemostatic disturbances. Samples of blood, lung and skin were collected and analyzed at 3 and 6 h. Platelet counts were markedly diminished in rats, and neither Na2-EDTA nor AEBSF could effectively abrogate this fall. However, Na2-EDTA markedly reduced plasma fibrinogen consumption and hemorrhage at the site of BjV inoculation. Na2-EDTA also abolished the marked elevation in TF levels in plasma at 3 and 6 h, by both administration routes. Moreover, increased TF activity was also noticed in lung and skin tissue samples at 6 h. However, factor VII levels did not decrease over time. PDI expression in skin was normal at 3 h, and downregulated at 6 h in all groups treated with BjV. Conclusions SVMP induce coagulopathy, hemorrhage and increased TF levels in plasma, but neither SVMP nor SVSP are directly involved in thrombocytopenia. High levels of TF in plasma and TF decryption occur during snake envenomation, like true disseminated intravascular coagulation syndrome, and might be implicated in engendering bleeding manifestations in severely-envenomed patients. PMID:24831016

  20. Bothrops jararaca peptide with anti-hypertensive action normalizes endothelium dysfunction involved in physiopathology of preeclampsia.

    PubMed

    Benedetti, Gabriel; Morais, Katia L P; Guerreiro, Juliano R; de Oliveira, Eduardo Fontana; Hoshida, Mara Sandra; Oliveira, Leandro; Sass, Nelson; Lebrun, Ivo; Ulrich, Henning; Lameu, Claudiana; de Camargo, Antonio Carlos Martins

    2011-01-01

    Preeclampsia, a pregnancy-specific syndrome characterized by hypertension, proteinuria and edema, is a major cause of fetal and maternal morbidity and mortality especially in developing countries. Bj-PRO-10c, a proline-rich peptide isolated from Bothrops jararaca venom, has been attributed with potent anti-hypertensive effects. Recently, we have shown that Bj-PRO-10c-induced anti-hypertensive actions involved NO production in spontaneous hypertensive rats. Using in vitro studies we now show that Bj-PRO-10c was able to increase NO production in human umbilical vein endothelial cells from hypertensive pregnant women (HUVEC-PE) to levels observed in HUVEC of normotensive women. Moreover, in the presence of the peptide, eNOS expression as well as argininosuccinate synthase activity, the key rate-limiting enzyme of the citrulline-NO cycle, were enhanced. In addition, excessive superoxide production due to NO deficiency, one of the major deleterious effects of the disease, was inhibited by Bj-PRO-10c. Bj-PRO-10c induced intracellular calcium fluxes in both, HUVEC-PE and HUVEC, which, however, led to activation of eNOS expression only in HUVEC-PE. Since Bj-PRO-10c promoted biological effects in HUVEC from patients suffering from the disorder and not in normotensive pregnant women, we hypothesize that Bj-PRO-10c induces its anti-hypertensive effect in mothers with preeclampsia. Such properties may initiate the development of novel therapeutics for treating preeclampsia. PMID:21858206

  1. Comparison of Serpent and HELIOS-2 as applied for the PWR few-group cross section generation

    SciTech Connect

    Fridman, E.; Leppaenen, J.; Wemple, C.

    2013-07-01

    This paper discusses recent modifications to the Serpent Monte Carlo code methodology and related to the calculation of few-group diffusion coefficients and reflector discontinuity factors The new methods were assessed in the following manner. First, few-group homogenized cross sections calculated by Serpent for a reference PWR core were compared with those generated 1 commercial deterministic lattice transport code HELIOS-2. Second, Serpent and HELIOS-2 fe group cross section sets were later employed by nodal diffusion code DYN3D for the modeling the reference PWR core. Finally, the nodal diffusion results obtained using the both cross section sets were compared with the full core Serpent Monte Carlo solution. The test calculations show that Serpent can calculate the parameters required for nodal analyses similar to conventional deterministic lattice codes. (authors)

  2. Ultrastructure of spermiogenesis in the Cottonmouth, Agkistrodon piscivorus (Squamata: Viperidae: Crotalinae).

    PubMed

    Gribbins, Kevin M; Rheubert, Justin L; Anzalone, Marla L; Siegel, Dustin S; Sever, David M

    2010-03-01

    To date multiple studies exist that examine the morphology of spermatozoa. However, there are limited numbers of data detailing the ontogenic characters of spermiogenesis within squamates. Testicular tissues were collected from Cottonmouths (Agkistrodon piscivorus) and tissues from spermiogenically active months were analyzed ultrastructurally to detail the cellular changes that occur during spermiogenesis. The major events of spermiogenesis (acrosome formation, nuclear elongation/DNA condensation, and flagellar development) resemble that of other squamates; however, specific ultrastructural differences can be observed between Cottonmouths and other squamates studied to date. During acrosome formation vesicles from the Golgi apparatus fuse at the apical surface of the nuclear membrane prior to making nuclear contact. At this stage, the acrosome granule can be observed in a centralized location within the vesicle. As elongation commences the acrosome complex becomes highly compartmentalized and migrates laterally along the nucleus. Parallel and circum-cylindrical microtubules (components of the manchette) are observed with parallel microtubules outnumbering the circum-cylindrical microtubules. Flagella, displaying the conserved 9 + 2 microtubule arrangement, sit in nuclear fossae that have electron lucent shoulders juxtaposed on either side of the spermatids basal plates. This study aims to provide developmental characters for squamates in the subfamily Crotalinae, family Viperidae, which may be useful for histopathological studies on spermatogenesis in semi-aquatic species exposed to pesticides. Furthermore, these data in the near future may provide morphological characters for spermiogenesis that can be added to morphological data matrices that may be used in phylogenetic analyses. PMID:19827154

  3. Aqueous leaf extract of Jatropha gossypiifolia L. (Euphorbiaceae) inhibits enzymatic and biological actions of Bothrops jararaca snake venom.

    PubMed

    Félix-Silva, Juliana; Souza, Thiago; Menezes, Yamara A S; Cabral, Bárbara; Câmara, Rafael B G; Silva-Junior, Arnóbio A; Rocha, Hugo A O; Rebecchi, Ivanise M M; Zucolotto, Silvana M; Fernandes-Pedrosa, Matheus F

    2014-01-01

    Snakebites are a serious public health problem due their high morbi-mortality. The main available specific treatment is the antivenom serum therapy, which has some disadvantages, such as poor neutralization of local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies is relevant. Therefore, the aim of this study was to evaluate the antiophidic properties of Jatropha gossypiifolia, a medicinal plant used in folk medicine to treat snakebites. The aqueous leaf extract of the plant was prepared by decoction and phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins. The extract was able to inhibit enzymatic and biologic activities induced by Bothrops jararaca snake venom in vitro and in vivo. The blood incoagulability was efficiently inhibited by the extract by oral route. The hemorrhagic and edematogenic local effects were also inhibited, the former by up to 56% and the latter by 100%, in animals treated with extract by oral and intraperitoneal routes, respectively. The inhibition of myotoxic action of B. jararaca reached almost 100%. According to enzymatic tests performed, it is possible to suggest that the antiophidic activity may be due an inhibitory action upon snake venom metalloproteinases (SVMPs) and/or serine proteinases (SVSPs), including fibrinogenolytic enzymes, clotting factors activators and thrombin like enzymes (SVTLEs), as well upon catalytically inactive phospholipases A2 (Lys49 PLA2). Anti-inflammatory activity, at least partially, could also be related to the inhibition of local effects. Additionally, protein precipitating and antioxidant activities may also be important features contributing to the activity presented. In conclusion, the results demonstrate the potential antiophidic activity of J. gossypiifolia extract, including its significant action upon local effects, suggesting that it may be used as a new source of bioactive molecules against bothropic venom. PMID:25126759

  4. Aqueous Leaf Extract of Jatropha gossypiifolia L. (Euphorbiaceae) Inhibits Enzymatic and Biological Actions of Bothrops jararaca Snake Venom

    PubMed Central

    Félix-Silva, Juliana; Souza, Thiago; Menezes, Yamara A. S.; Cabral, Bárbara; Câmara, Rafael B. G.; Silva-Junior, Arnóbio A.; Rocha, Hugo A. O.; Rebecchi, Ivanise M. M.; Zucolotto, Silvana M.; Fernandes-Pedrosa, Matheus F.

    2014-01-01

    Snakebites are a serious public health problem due their high morbi-mortality. The main available specific treatment is the antivenom serum therapy, which has some disadvantages, such as poor neutralization of local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies is relevant. Therefore, the aim of this study was to evaluate the antiophidic properties of Jatropha gossypiifolia, a medicinal plant used in folk medicine to treat snakebites. The aqueous leaf extract of the plant was prepared by decoction and phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins. The extract was able to inhibit enzymatic and biologic activities induced by Bothrops jararaca snake venom in vitro and in vivo. The blood incoagulability was efficiently inhibited by the extract by oral route. The hemorrhagic and edematogenic local effects were also inhibited, the former by up to 56% and the latter by 100%, in animals treated with extract by oral and intraperitoneal routes, respectively. The inhibition of myotoxic action of B. jararaca reached almost 100%. According to enzymatic tests performed, it is possible to suggest that the antiophidic activity may be due an inhibitory action upon snake venom metalloproteinases (SVMPs) and/or serine proteinases (SVSPs), including fibrinogenolytic enzymes, clotting factors activators and thrombin like enzymes (SVTLEs), as well upon catalytically inactive phospholipases A2 (Lys49 PLA2). Anti-inflammatory activity, at least partially, could also be related to the inhibition of local effects. Additionally, protein precipitating and antioxidant activities may also be important features contributing to the activity presented. In conclusion, the results demonstrate the potential antiophidic activity of J. gossypiifolia extract, including its significant action upon local effects, suggesting that it may be used as a new source of bioactive molecules against bothropic venom. PMID:25126759

  5. Development of a dynamic simulation mode in Serpent 2 Monte Carlo code

    SciTech Connect

    Leppaenen, J.

    2013-07-01

    This paper presents a dynamic neutron transport mode, currently being implemented in the Serpent 2 Monte Carlo code for the purpose of simulating short reactivity transients with temperature feedback. The transport routine is introduced and validated by comparison to MCNP5 calculations. The method is also tested in combination with an internal temperature feedback module, which forms the inner part of a multi-physics coupling scheme in Serpent 2. The demo case for the coupled calculation is a reactivity-initiated accident (RIA) in PWR fuel. (authors)

  6. Lachesis muta (Viperidae) cDNAs Reveal Diverging Pit Viper Molecules and Scaffolds Typical of Cobra (Elapidae) Venoms: Implications for Snake Toxin Repertoire Evolution

    PubMed Central

    Junqueira-de-Azevedo, Inácio L. M.; Ching, Ana T. C.; Carvalho, Eneas; Faria, Fernanda; Nishiyama, Milton Y.; Ho, Paulo L.; Diniz, Marcelo R. V.

    2006-01-01

    Efforts to describe toxins from the two major families of venomous snakes (Viperidae and Elapidae) usually reveal proteins belonging to few structural types, particular of each family. Here we carried on an effort to determine uncommon cDNAs that represent possible new toxins from Lachesis muta (Viperidae). In addition to nine classes of typical toxins, atypical molecules never observed in the hundreds of Viperidae snakes studied so far are highly expressed: a diverging C-type lectin that is related to Viperidae toxins but appears to be independently originated; an ohanin-like toxin, which would be the third member of the most recently described class of Elapidae toxins, related to human butyrophilin and B30.2 proteins; and a 3FTx-like toxin, a new member of the widely studied three-finger family of proteins, which includes major Elapidae neurotoxins and CD59 antigen. The presence of these common and uncommon molecules suggests that the repertoire of toxins could be more conserved between families than has been considered, and their features indicate a dynamic process of venom evolution through molecular mechanisms, such as multiple recruitments of important scaffolds and domain exchange between paralogs, always keeping a minimalist nature in most toxin structures in opposition to their nontoxin counterparts. PMID:16582429

  7. Type specimens of Crotalus scutulatus (Chordata: Reptilia: Squamata: Viperidae) re-examined, with new evidence after more than a century of confusion

    USGS Publications Warehouse

    Cardwell, Michael D.; Gotte, Steve W.; McDiarmid, Roy W.; Gilmore, Ned; Poindexter, James A.

    2013-01-01

    The original description of Crotalus scutulatus (Chordata: Reptilia: Squamata: Viperidae) was published in 1861 by Robert Kennicott, who did not identify a type specimen or a type locality. We review the history of specimens purported to be the type(s) and various designations of type locality. We provide evidence that ANSP 7069 (formerly one of two specimens of USNM 5027) is the holotype and that the appropriate type locality is Fort Buchanan, near present-day Sonoita, in Santa Cruz County, Arizona.

  8. Revised methods for few-group cross sections generation in the Serpent Monte Carlo code

    SciTech Connect

    Fridman, E.; Leppaenen, J.

    2012-07-01

    This paper presents new calculation methods, recently implemented in the Serpent Monte Carlo code, and related to the production of homogenized few-group constants for deterministic 3D core analysis. The new methods fall under three topics: 1) Improved treatment of neutron-multiplying scattering reactions, 2) Group constant generation in reflectors and other non-fissile regions and 3) Homogenization in leakage-corrected criticality spectrum. The methodology is demonstrated by a numerical example, comparing a deterministic nodal diffusion calculation using Serpent-generated cross sections to a reference full-core Monte Carlo simulation. It is concluded that the new methodology improves the results of the deterministic calculation, and paves the way for Monte Carlo based group constant generation. (authors)

  9. Validation of the Serpent 2 code on TRIGA Mark II benchmark experiments.

    PubMed

    ?ali?, Dušan; Žerovnik, Gašper; Trkov, Andrej; Snoj, Luka

    2016-01-01

    The main aim of this paper is the development and validation of a 3D computational model of TRIGA research reactor using Serpent 2 code. The calculated parameters were compared to the experimental results and to calculations performed with the MCNP code. The results show that the calculated normalized reaction rates and flux distribution within the core are in good agreement with MCNP and experiment, while in the reflector the flux distribution differ up to 3% from the measurements. PMID:26516989

  10. An alternative micromethod to access the procoagulant activity of Bothrops jararaca venom and the efficacy of antivenom.

    PubMed

    Oguiura, N; Kapronezai, J; Ribeiro, T; Rocha, M M T; Medeiros, C R; Marcelino, J R; Prezoto, B C

    2014-11-01

    The assessment of the capacity of antivenoms to neutralize the lethal activity of snake venoms still relies largely on traditional rodent lethality assay (LD50). However, adequately validated in vitro tests should be introduced for assessing antivenom neutralizing capacity in plasma of immunized horses as well as for in-process quality control. The dynamic of fibrin formation in recalcified avian plasma samples is extremely slow, when compared to that presented by mammalian plasmas. In this study, we present one new coagulant assay, by performing dose-response curve after plotting the clotting time (CT) parameter of the ROTEM profile of recalcified chicken plasma samples (target) against semi-logarithmic doses of Bothrops jararaca venom (agonist), either in absence or in presence of the semi-logarithmic doses of anti-bothropic serum (ABS) (antagonist). The mean coagulant dose 50% (CD50) was defined as the quantity of venom (in ?g) which reduces CT to 900 s, between minimum and maximum responses. The CT induced by 5CD50 of the venom was used as the control for calculating the effective dose (ED) of each batch of ABS. ED was defined as the ABS dose (nanoliters, nL) at which CT induced by one amount of venom corresponding to 5CD50 is displaced to the maximum threshold (1800 s). Five batches of the ABS, previously assayed for their lethality neutralizing activity (ED50) were assayed. The correlation coefficient (r) between both in vitro (ED) and in vivo (ED50) values was 0.87 (p value < 0.05). We propose this micro method as highly sensitive for characterization and quantification of possible procoagulant activity of small doses of snake venoms (nanograms) and for detecting small doses (nanoliters) of specific antibodies against this effect in little volume samples of biological fluids. PMID:25128708

  11. Venom-Related Transcripts from Bothrops jararaca Tissues Provide Novel Molecular Insights into the Production and Evolution of Snake Venom

    PubMed Central

    Junqueira-de-Azevedo, Inácio L.M.; Bastos, Carolina Mancini Val; Ho, Paulo Lee; Luna, Milene Schmidt; Yamanouye, Norma; Casewell, Nicholas R.

    2015-01-01

    Attempts to reconstruct the evolutionary history of snake toxins in the context of their co-option to the venom gland rarely account for nonvenom snake genes that are paralogous to toxins, and which therefore represent important connectors to ancestral genes. In order to reevaluate this process, we conducted a comparative transcriptomic survey on body tissues from a venomous snake. A nonredundant set of 33,000 unigenes (assembled transcripts of reference genes) was independently assembled from six organs of the medically important viperid snake Bothrops jararaca, providing a reference list of 82 full-length toxins from the venom gland and specific products from other tissues, such as pancreatic digestive enzymes. Unigenes were then screened for nontoxin transcripts paralogous to toxins revealing 1) low level coexpression of approximately 20% of toxin genes (e.g., bradykinin-potentiating peptide, C-type lectin, snake venom metalloproteinase, snake venom nerve growth factor) in body tissues, 2) the identity of the closest paralogs to toxin genes in eight classes of toxins, 3) the location and level of paralog expression, indicating that, in general, co-expression occurs in a higher number of tissues and at lower levels than observed for toxin genes, and 4) strong evidence of a toxin gene reverting back to selective expression in a body tissue. In addition, our differential gene expression analyses identify specific cellular processes that make the venom gland a highly specialized secretory tissue. Our results demonstrate that the evolution and production of venom in snakes is a complex process that can only be understood in the context of comparative data from other snake tissues, including the identification of genes paralogous to venom toxins. PMID:25502939

  12. Venom-related transcripts from Bothrops jararaca tissues provide novel molecular insights into the production and evolution of snake venom.

    PubMed

    Junqueira-de-Azevedo, Inácio L M; Bastos, Carolina Mancini Val; Ho, Paulo Lee; Luna, Milene Schmidt; Yamanouye, Norma; Casewell, Nicholas R

    2015-03-01

    Attempts to reconstruct the evolutionary history of snake toxins in the context of their co-option to the venom gland rarely account for nonvenom snake genes that are paralogous to toxins, and which therefore represent important connectors to ancestral genes. In order to reevaluate this process, we conducted a comparative transcriptomic survey on body tissues from a venomous snake. A nonredundant set of 33,000 unigenes (assembled transcripts of reference genes) was independently assembled from six organs of the medically important viperid snake Bothrops jararaca, providing a reference list of 82 full-length toxins from the venom gland and specific products from other tissues, such as pancreatic digestive enzymes. Unigenes were then screened for nontoxin transcripts paralogous to toxins revealing 1) low level coexpression of approximately 20% of toxin genes (e.g., bradykinin-potentiating peptide, C-type lectin, snake venom metalloproteinase, snake venom nerve growth factor) in body tissues, 2) the identity of the closest paralogs to toxin genes in eight classes of toxins, 3) the location and level of paralog expression, indicating that, in general, co-expression occurs in a higher number of tissues and at lower levels than observed for toxin genes, and 4) strong evidence of a toxin gene reverting back to selective expression in a body tissue. In addition, our differential gene expression analyses identify specific cellular processes that make the venom gland a highly specialized secretory tissue. Our results demonstrate that the evolution and production of venom in snakes is a complex process that can only be understood in the context of comparative data from other snake tissues, including the identification of genes paralogous to venom toxins. PMID:25502939

  13. Validating the Serpent Model of FiR 1 Triga Mk-II Reactor by Means of Reactor Dosimetry

    NASA Astrophysics Data System (ADS)

    Viitanen, Tuomas; Leppänen, Jaakko

    2016-02-01

    A model of the FiR 1 Triga Mk-II reactor has been previously generated for the Serpent Monte Carlo reactor physics and burnup calculation code. In the current article, this model is validated by comparing the predicted reaction rates of nickel and manganese at 9 different positions in the reactor to measurements. In addition, track-length estimators are implemented in Serpent 2.1.18 to increase its performance in dosimetry calculations. The usage of the track-length estimators is found to decrease the reaction rate calculation times by a factor of 7-8 compared to the standard estimator type in Serpent, the collision estimators. The differences in the reaction rates between the calculation and the measurement are below 20%.

  14. A collision history-based approach to Sensitivity/Perturbation calculations in the continuous energy Monte Carlo code SERPENT

    SciTech Connect

    Giuseppe Palmiotti

    2015-05-01

    In this work, the implementation of a collision history-based approach to sensitivity/perturbation calculations in the Monte Carlo code SERPENT is discussed. The proposed methods allow the calculation of the eects of nuclear data perturbation on several response functions: the eective multiplication factor, reaction rate ratios and bilinear ratios (e.g., eective kinetics parameters). SERPENT results are compared to ERANOS and TSUNAMI Generalized Perturbation Theory calculations for two fast metallic systems and for a PWR pin-cell benchmark. New methods for the calculation of sensitivities to angular scattering distributions are also presented, which adopts fully continuous (in energy and angle) Monte Carlo estimators.

  15. Phospholipases a2 from Viperidae snakes: Differences in membranotropic activity between enzymatically active toxin and its inactive isoforms.

    PubMed

    Ghazaryan, Narine A; Ghulikyan, Lusine; Kishmiryan, Arsen; Andreeva, Tatyana V; Utkin, Yuri N; Tsetlin, Victor I; Lomonte, Bruno; Ayvazyan, Naira M

    2015-02-01

    We describe the interaction of various phospholipases A2 (PLA2) from snake venoms of the family Viperidae (Macrovipera lebetina obtusa, Vipera ursinii renardi, Bothrops asper) with giant unilamellar vesicles (GUVs) composed of natural brain phospholipids mixture, visualized through fluorescence microscopy. The membrane fluorescent probes 8-anilino-1-naphthalenesulfonicacid (ANS), LAUDRAN and PRODAN were used to assess the state of the membrane and specifically mark the lipid packing and membrane fluidity. Our results have shown that the three PLA2s which contain either of aspartic acid, serine, or lysine residues at position 49 in the catalytic center, have different effects on the vesicles. The PLA2 with aspartic acid at this position causes the oval deformation of the vesicles, while serine and lysine-containing enzymes lead to an appreciable increase of fluorescence intensity in the vesicles membrane, wherein the shape and dimensions of GUVs have not changed, but in this case GUV aggregation occurs. LAURDAN and PRODAN detect the extent of water penetration into the bilayer surface. We calculated generalized polarization function (GP), showing that for all cases (D49 PLA2, S49 PLA2 and K49 PLA2) both LAUDRAN and PRODAN GP values decrease. A higher LAURDAN GP is indicative of low water penetration in the lipid bilayer in case of K49 PLA2 compared with D49 PLA2, whereas the PRODAN mainly gives information when lipid is in liquid crystalline phase. PMID:25450350

  16. [Sequencing and analysis of the complete mitochondrial genome of the King Cobra, Ophiophagus hannah (Serpents: Elapidae)].

    PubMed

    Chen, Nian; Lai, Xiao-Ping

    2010-07-01

    We obtained the complete mitochondrial genome of King Cobra(GenBank accession number: EU_921899) by Ex Taq-PCR, TA-cloning and primer-walking methods. This genome is very similar to other vertebrate, which is 17 267 bp in length and encodes 38 genes (including 13 protein-coding, 2 ribosomal RNA and 23 transfer RNA genes) and two long non-coding regions. The duplication of tRNA-Ile gene forms a new mitochondrial gene rearrangement model. Eight tRNA genes and one protein genes were transcribed from L strand, and the other genes were transcribed genes from H strand. Genes on the H strand show a fairly similar content of Adenosine and Thymine respectively, whereas those on the L strand have higher proportion of A than T. Combined rDNA sequence data (12S+16S rRNA) were used to reconstruct the phylogeny of 21 snake species for which complete mitochondrial genome sequences were available in the public databases. This large data set and an appropriate range of outgroup taxa demonstrated that Elapidae is more closely related to colubridae than viperidae, which supports the traditional viewpoints. PMID:20650853

  17. Identification and molecular characterization of five putative toxins from the venom gland of the snake Philodryas chamissonis (Serpentes: Dipsadidae).

    PubMed

    Urra, Félix A; Pulgar, Rodrigo; Gutiérrez, Ricardo; Hodar, Christian; Cambiazo, Verónica; Labra, Antonieta

    2015-12-15

    Philodryas chamissonis is a rear-fanged snake endemic to Chile. Its bite produces mild to moderate symptoms with proteolytic and anti-coagulant effects. Presently, the composition of the venom, as well as, the biochemical and structural characteristics of its toxins, remains unknown. In this study, we cloned and reported the first full-length sequences of five toxin-encoding genes from the venom gland of this species: Type III snake venom metalloprotease (SVMP), snake venom serine protease (SVSP), Cysteine-rich secretory protein (CRISP), ? and ? subunits of C-type lectin-like protein (CLP) and C-type natriuretic peptide (NP). These genes are highly expressed in the venom gland and their sequences exhibited a putative signal peptide, suggesting that these are components of the venom. These putative toxins had different evolutionary relationships with those reported for some front-fanged snakes, being SVMP, SVSP and CRISP of P. chamissonis closely related to the toxins present in Elapidae species, while NP was more related to those of Viperidae species. In addition, analyses suggest that the ? and ? subunits of CLP of P. chamissonis might have a ?-subunit scaffold in common with Viperidae species, whose highly variable C-terminal region might have allowed the diversification in ? and ? subunits. Our results provide the first molecular description of the toxins possibly implicated in the envenomation of prey and humans by the bite of P. chamissonis. PMID:26410112

  18. The Anti-Inflammatory Effects of the Methanolic Extract and Fractions from Davilla elliptica St. Hil. (Dilleniaceae) on Bothrops jararaca Envenomation.

    PubMed

    Nishijima, Catarine Massucato; Delella, Flavia Karina; Rodrigues, Clenilson Martins; Rinaldo, Daniel; Lopes-Ferreira, Monica Valdyrce dos Anjos; da Rocha, Lucia Regina Machado; Vilegas, Wagner; Felisbino, Sergio Luis; Hiruma-Lima, Clélia Akiko

    2015-01-01

    Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity. PMID:26042466

  19. Effects of N-acetyl-L-cysteine on redox status and markers of renal function in mice inoculated with Bothrops jararaca and Crotalus durissus terrificus venoms.

    PubMed

    Barone, Juliana Marton; Frezzatti, Rodrigo; Silveira, Paulo Flavio

    2014-03-01

    Renal dysfunction is an important aggravating factor in accidents caused by Crotalus durissus terrificus (Cdt) and Bothrops jararaca (Bj) bites. N-acetyl-l-cysteine (NAC) is well known as a nephroprotective antioxidant with low toxicity. The present study investigated the effects of NAC on redox status and markers of renal function in mice that received vehicle (controls) or venoms (v) of Cdt and Bj. In controls NAC promoted hypercreatinemia, hypouremia, hyperosmolality with decreased urea in urine, hyperproteinuria, decreased protein and increased dipeptidyl peptidase IV (DPPIV) in membrane-bound fraction (MF) from renal cortex (RC) and medulla (RM). NAC ameliorated or normalized altered creatinuria, proteinemia and aminopeptidase (AP) acid in MF, AP basic (APB) in soluble fraction (SF), and neutral AP in SF and MF from RC and RM in vBj envenomation. NAC ameliorated or normalized altered neutral AP in SF from RC and RM, and DPPIV and protein in MF from RC in vCdt envenomation. NAC ameliorated or restored renal redox status respectively in vCdt and vBj, and normalized uricemia in both envenomations. These data are promising perspectives that recommend the clinical evaluation of NAC as potential coadjuvant in the anti venom serotherapy for accidents with these snake's genera. PMID:24412461

  20. The Anti-Inflammatory Effects of the Methanolic Extract and Fractions from Davilla elliptica St. Hil. (Dilleniaceae) on Bothrops jararaca Envenomation

    PubMed Central

    Nishijima, Catarine Massucato; Delella, Flavia Karina; Rodrigues, Clenilson Martins; Rinaldo, Daniel; Lopes-Ferreira, Monica Valdyrce dos Anjos; da Rocha, Lucia Regina Machado; Vilegas, Wagner; Felisbino, Sergio Luis; Hiruma-Lima, Clélia Akiko

    2015-01-01

    Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity. PMID:26042466

  1. The hemoglobin system of the serpent eel Ophisurus serpens: structural and functional characterization.

    PubMed

    Manconi, Barbara; Pellegrini, Mariagiuseppina; Messana, Irene; Sanna, Maria Teresa; Castagnola, Massimo; Iavarone, Federica; Coluccia, Elisabetta; Giardina, Bruno; Olianas, Alessandra

    2013-10-01

    The hemoglobin system of the serpent eel Ophisurus serpens was structurally and functionally characterized with the aim of comparing it to the hemoglobin system of other fish species, as oxygen loading under the severe habitat conditions experienced by O. serpens could have necessitated specific adaptation mechanisms during evolution. The hemoglobin system of O. serpens includes one cathodic and four anodic components. The molecular mass of the α and β chains of the cathodic component as well as the 2 α and 4 β of the anodic components were determined. Analysis of the intact α and β chains from cathodic hemoglobin and their proteolytic digestion products by high-resolution MS and MS/MS experiments resulted in 92 and 95 % sequence coverage of the α and β globins, respectively. The oxygen binding properties of both hemoglobin components were analyzed with respect to their interactions with their physiological effectors. Stripped cathodic hemoglobin displayed the highest oxygen affinity among Anguilliformes with no significant effect of pH on O2-affinity. In the presence of both chloride and organic phosphates, O2-affinity was strongly reduced, and cooperativity was enhanced; moreover, cathodic hemoglobin contains two indistinguishable GTP-binding sites. Stripped anodic hemoglobins exhibited both low O2-affinity and low cooperativity and a larger Bohr effect than cathodic hemoglobin. The cathodic hemoglobin of O. serpens and the corresponding component of Conger conger share the greatest structural and functional similarity among hemoglobin systems of Anguilliformes studied to date, consistent with their phylogenetic relationship. PMID:23632627

  2. Internal neutronics-temperature coupling in Serpent 2 - Reactivity differences resulting from choice of material property correlations

    SciTech Connect

    Valtavirta, V.

    2013-07-01

    This paper describes the unique way of simultaneously solving the power and temperature distributions of a nuclear system with the Monte Carlo neutron transport code Serpent 2. The coupled solution is achieved through the implementation of an internal temperature solver and material property correlations in the code. The program structure is reviewed concerning the temperature solver and the internal correlations as well as the internal coupling between these two and the neutron transport part. To estimate the reactivity differences resulting from correlation choices a simple pin-cell case has been calculated. It is established, that some correlation choices may result in difference in reactivity of approximately 100 pcm. (authors)

  3. Cyclin-dependent Kinase 8 Module Expression Profiling Reveals Requirement of Mediator Subunits 12 and 13 for Transcription of Serpent-dependent Innate Immunity Genes in Drosophila*

    PubMed Central

    Kuuluvainen, Emilia; Hakala, Heini; Havula, Essi; Sahal Estimé, Michelle; Rämet, Mika; Hietakangas, Ville; Mäkelä, Tomi P.

    2014-01-01

    The Cdk8 (cyclin-dependent kinase 8) module of Mediator integrates regulatory cues from transcription factors to RNA polymerase II. It consists of four subunits where Med12 and Med13 link Cdk8 and cyclin C (CycC) to core Mediator. Here we have investigated the contributions of the Cdk8 module subunits to transcriptional regulation using RNA interference in Drosophila cells. Genome-wide expression profiling demonstrated separation of Cdk8-CycC and Med12-Med13 profiles. However, transcriptional regulation by Cdk8-CycC was dependent on Med12-Med13. This observation also revealed that Cdk8-CycC and Med12-Med13 often have opposite transcriptional effects. Interestingly, Med12 and Med13 profiles overlapped significantly with that of the GATA factor Serpent. Accordingly, mutational analyses indicated that GATA sites are required for Med12-Med13 regulation of Serpent-dependent genes. Med12 and Med13 were also found to be required for Serpent-activated innate immunity genes in defense to bacterial infection. The results reveal a novel role for the Cdk8 module in Serpent-dependent transcription and innate immunity. PMID:24778181

  4. Epidemiology of venomous and semi-venomous snakebites (Ophidia: Viperidae, Colubridae) in the Kashan city of the Isfahan province in Central Iran

    PubMed Central

    Dehghani, Rouhullah; Mehrpour, Omid; Shahi, Morteza Panjeh; Jazayeri, Mehrdad; Karrari, Parissa; Keyler, Dan; Zamani, Nasim

    2014-01-01

    Background: Information on the epidemiology of venomous snake species responsible for envenomation to humans in Iran has not been well documented. In the Kashan city, venomous snakebite remains a recurring medical problem. Information providing the correct identification of snake species responsible for envenomation in this geographic region would be useful to regional medical clinics and personnel for the effective and optimal management of the patients. Materials and Methods: In this cross-sectional study, all patient data was collected from Kashan city and its suburbs. The specific data relating to the taxonomic identification of snakes responsible for envenomation were evaluated. A general approach to the diagnosis and management of patients was also provided. Snakes responsible for bites were transported to a laboratory, where their taxonomic classification was confirmed based on key anatomical features and morphological characteristics. Results: A total of 46 snakes were examined. Of these, 37 (80%) were non-venomous species, and 9 (20%) were identified as venomous. Seven of the nine venomous snake species (78%) were of the family Viperidae, and two specimens (22%) were in the family Colubridae. Specifically, the viperid species were Macrovipera lebetina obtusa, Pseudocerastes persicus, Pseudocerastes fieldi, and Echis carinatus. The two colubrid species were Malpolon monspessulanus insignitus and Psammophis schkari. Conclusion: Five different species of venomous snakes responsible for envenomation in the Kashan city region were confirmed. The viper, P. fieldi, was reported for the first time in the central part of Iran. PMID:24672563

  5. A Place of Transformation: Lessons from the Cosmic Serpent Informal Science Education Professional Development Project

    NASA Astrophysics Data System (ADS)

    Peticolas, L.; Maryboy, N.; Begay, D.; Stein, J.; Valdez, S.; Paglierani, R.

    2012-08-01

    A cultural disconnect exists between Western scientists and educators and Native communities in terms of scientific worldviews and Indigenous ways of knowing. This cultural disconnect manifests itself in the lack of participation of Native Americans in Western science and a lack of appreciation by Western scientists of Native science. Our NSF-Funded project "Cosmic Serpent: Bridging Native and Western Learning in Museum Settings" set out to provide a way for informal science education practitioners and tribal museum practitioners to learn about these two worldviews in such a way as to inform their educational practice around these concepts. We began with a pilot workshop in year one of this four-year project. We then provided two week-long professional development workshops in three regions within the Western U.S., and culminated with a final conference for all participants. In total, the workshops served 162 participants, including 115 practitioners from 19 tribal museums and 41 science, natural history, and cultural museums; 23 tribal community members; and 24 "bridge people" with knowledge of both Indigenous and Western science. For this article, we focus on the professional and personal transformations around culture, knowledge, science, and worldviews that occurred as a part of this project. We evaluated the collaborative aspects of this grant between the Indigenous Education Institute; the Center for Science Education at the University of California, Berkeley; the Institute for Learning Innovation; Native Pathways; Association for Science and Technology Centers; and the National Museum of the American Indian. Using evaluation results, as well as our personal reflections, we share our learnings from a place of transformation. We provide lessons we learned with this project, which we hope others will find relevant to their own science education work.

  6. Molecular cloning and characterization of satellite DNA sequences from constitutive heterochromatin of the habu snake (Protobothrops flavoviridis, Viperidae) and the Burmese python (Python bivittatus, Pythonidae).

    PubMed

    Matsubara, Kazumi; Uno, Yoshinobu; Srikulnath, Kornsorn; Seki, Risako; Nishida, Chizuko; Matsuda, Yoichi

    2015-12-01

    Highly repetitive DNA sequences of the centromeric heterochromatin provide valuable molecular cytogenetic markers for the investigation of genomic compartmentalization in the macrochromosomes and microchromosomes of sauropsids. Here, the relationship between centromeric heterochromatin and karyotype evolution was examined using cloned repetitive DNA sequences from two snake species, the habu snake (Protobothrops flavoviridis, Crotalinae, Viperidae) and Burmese python (Python bivittatus, Pythonidae). Three satellite DNA (stDNA) families were isolated from the heterochromatin of these snakes: 168-bp PFL-MspI from P. flavoviridis and 196-bp PBI-DdeI and 174-bp PBI-MspI from P. bivittatus. The PFL-MspI and PBI-DdeI sequences were localized to the centromeric regions of most chromosomes in the respective species, suggesting that the two sequences were the major components of the centromeric heterochromatin in these organisms. The PBI-MspI sequence was localized to the pericentromeric region of four chromosome pairs. The PFL-MspI and the PBI-DdeI sequences were conserved only in the genome of closely related species, Gloydius blomhoffii (Crotalinae) and Python molurus, respectively, although their locations on the chromosomes were slightly different. In contrast, the PBI-MspI sequence was also in the genomes of P. molurus and Boa constrictor (Boidae), and additionally localized to the centromeric regions of eight chromosome pairs in B. constrictor, suggesting that this sequence originated in the genome of a common ancestor of Pythonidae and Boidae, approximately 86 million years ago. The three stDNA sequences showed no genomic compartmentalization between the macrochromosomes and microchromosomes, suggesting that homogenization of the centromeric and/or pericentromeric stDNA sequences occurred in the macrochromosomes and microchromosomes of these snakes. PMID:26205503

  7. Discovery of microscopic evidence for shock metamorphism at the Serpent Mound structure, south-central Ohio: Confirmation of an origin by impact

    USGS Publications Warehouse

    Carlton, R.W.; Koeberl, C.; Baranoski, M.T.; SchuMacHer, G.A.

    1998-01-01

    The origin of the Serpent Mound structure in south-central Ohio has been disputed for many years. Clearly, more evidence was needed to resolve the confusion concerning the origin of the Serpent Mound feature either by endogenic processes or by hypervelocity impact. A petrographic study of 21 samples taken from a core 903 m long drilled in the central uplift of the structure provides evidence of shock metamorphism in the form of multiple sets of planar deformation features in quartz grains, as well as the presence of clasts of altered impact-melt rock. Crystallographic orientations of the planar deformation features show maxima at the shock-characteristic planes of {101??3} and {101??2} and additional maxima at {101??1}, {213??1}, and {516??1}. Geochemical analyses of impact breccias show minor enrichments in the abundances of the siderophile elements Cr, Co, Ni, and Ir, indicating the presence of a minor meteoritic component.

  8. Anesthesia with isoflurane and sevoflurane in the crested serpent eagle (Spilornis cheela hoya): minimum anesthetic concentration, physiological effects, hematocrit, plasma chemistry and behavioral effects.

    PubMed

    Chan, Fang-Tse; Chang, Geng-Ruei; Wang, Hsien-Chi; Hsu, Tien-Huan

    2013-12-30

    The initial goal of this study was to determine the minimum anesthetic concentration (MAC) for isoflurane (ISO) and sevoflurane (SEVO) for the crested serpent eagle. Next, we compared the anesthetic effects of each on the physiological effects, hematocrit, plasma chemistry values and behavior in spontaneously breathing captive adult crested serpent eagles. Sixteen eagles were randomly allocated to two groups for anesthesia with ISO (n=8) or SEVO (n=8). First, we measured the MAC values of ISO and SEVO, and four weeks later, we investigated the effect of each on the physiological effects, hematocrit (HCT) and plasma chemistry values. The MAC values of ISO and SEVO for crested serpent eagles were 1.46 ± 0.30 and 2.03 ± 0.32%, respectively. The results revealed no significant differences between the two anesthetics in induction time, while time of extubation to recovery was significantly shorter with SEVO. A time-related increase in end-tidal CO? and decreases in body temperature and respiratory rates were observed during anesthesia with each anesthetic. There were no significant differences between the effect of the two anesthetics on heart rate, hematocrit, plasma chemistry values or respiration, although each caused minor respiration depression. We concluded that SEVO is a more effective inhalant agent than ISO for use in eagles, showing the most rapidest induction and recovery from anesthesia. PMID:23955396

  9. Anesthesia with Isoflurane and Sevoflurane in the Crested Serpent Eagle (Spilornis cheela hoya): Minimum Anesthetic Concentration, Physiological Effects, Hematocrit, Plasma Chemistry and Behavioral Effects

    PubMed Central

    CHAN, Fang-Tse; CHANG, Geng-Ruei; WANG, Hsien-Chi; HSU, Tien-Huan

    2013-01-01

    ABSTRACT The initial goal of this study was to determine the minimum anesthetic concentration (MAC) for isoflurane (ISO) and sevoflurane (SEVO) for the crested serpent eagle. Next, we compared the anesthetic effects of each on the physiological effects, hematocrit, plasma chemistry values and behavior in spontaneously breathing captive adult crested serpent eagles. Sixteen eagles were randomly allocated to two groups for anesthesia with ISO (n=8) or SEVO (n=8). First, we measured the MAC values of ISO and SEVO, and four weeks later, we investigated the effect of each on the physiological effects, hematocrit (HCT) and plasma chemistry values. The MAC values of ISO and SEVO for crested serpent eagles were 1.46 ± 0.30 and 2.03 ± 0.32%, respectively. The results revealed no significant differences between the two anesthetics in induction time, while time of extubation to recovery was significantly shorter with SEVO. A time-related increase in end-tidal CO2 and decreases in body temperature and respiratory rates were observed during anesthesia with each anesthetic. There were no significant differences between the effect of the two anesthetics on heart rate, hematocrit, plasma chemistry values or respiration, although each caused minor respiration depression. We concluded that SEVO is a more effective inhalant agent than ISO for use in eagles, showing the most rapidest induction and recovery from anesthesia. PMID:23955396

  10. Resolving an enigma by integrative taxonomy: Madagascarophis fuchsi (Serpentes: Lamprophiidae), a new opisthoglyphous and microendemic snake from northern Madagascar.

    PubMed

    Glaw, Frank; Kucharzewski, Christoph; Köhler, Jörn; Vences, Miguel; Nagy, Zoltán T

    2013-01-01

    Herpetological surveys in the dry forests of the limestone massif Montagne des Français in the far north of Madagascar have recently yielded a number of undescribed reptile species. Here we describe an additional new and potentially microendemic species of the snake genus Madagascarophis (Squamata: Serpentes: Pseudoxyrhophiinae) which lives in this massif syntopically with M. colubrinus septentrionalis and differs distinctly from M. colubrinus and M. meridionalis in its mitochondrial and nuclear DNA sequences. Morphologically Madagascarophis fuchsi sp. nov. is characterized by a broad contact between the posterior inframaxillaries (genials), 25 dorsal scale rows at midbody, and a low number of ventrals (171-172). We redescribe the holotype of M. ocellatus and present new data on the morphological variation of the northern subspecies M. c. septentrionalis and M. c. citrinus. Although Montagne des Français has recently been included into the network of nature reserves in Madagascar, continuous deforestation is strongly threatening this important center of reptile endemism. In line with the assessment of other microendemic reptiles of this massif we suggest to consider the new species as Critically Endangered according to the IUCN criteria and encourage new efforts to protect this area more efficiently. PMID:26131514

  11. The Descent of the Serpent: Using a Successful Ancient Solar Observatories Webcast from Chichen Itza to Highlight Space Weather Research

    NASA Astrophysics Data System (ADS)

    Hawkins, I.; Higdon, R.; Cline, T.

    2006-12-01

    Over the past seven years, NASA's Sun-Earth Connection Education Forum has sponsored and coordinated education and public outreach events to highlight NASA's heliophysics research and discoveries. Our strategy involves using celestial events, such as total solar eclipses and the Transit of Venus, as well as Sun-Earth Day during the March Equinox, to engage K-12 schools and the general public in space science activities, demonstrations, and interactions with space scientists. In collaboration with partners that include the Exploratorium and other museums, Ideum, NASA TV, NASA heliophysics missions, and others, we produce webcasts, other multi-media, and print resources for use by school and informal educators nation-wide and internationally. We provide training and professional development to K-12 educators, museum personnel, amateur astronomers, Girl Scout leaders, etc., so they can implement their own outreach programs taking advantage of our resources. A coordinated approach promotes multiple programs occurring each year under a common theme. As part of an Ancient Observatories theme in 2005, we have successfully featured solar alignments with ancient structures made by indigenous cultures that mark the equinoxes and/or solstices in cultural and historical parks in the Americas. In partnership with the Exploratorium, we produced broadcast-quality and webcast programming during the March equinox that shared heliophysics within a broad cultural context with formal and informal education audiences internationally. The program: "Descent of the Serpent" featured the light and shadow effect at sunset that takes place during the spring equinox at the Pyramid of El Castillo, in Chichén Itzá (México). This program made unique and authentic cultural connections to the knowledge of solar astronomy of the Maya, the living Mayan culture of today, and the importance of the Sun across the ages. We involved Sun-Earth Connection scientists, their missions, and research programs from México and the US to share NASA solar research with diverse audiences in the US and across the world, and to share how our dynamic Sun impacts the Earth and other planets in the solar system. During our presentation, we will highlight the strategies we used to successfully engage Hispanics of native heritage in heliophysics from all over the world.

  12. An extended version of the SERPENT-2 code to investigate fuel burn-up and core material evolution of the Molten Salt Fast Reactor

    NASA Astrophysics Data System (ADS)

    Aufiero, M.; Cammi, A.; Fiorina, C.; Leppänen, J.; Luzzi, L.; Ricotti, M. E.

    2013-10-01

    In this work, the Monte Carlo burn-up code SERPENT-2 has been extended and employed to study the material isotopic evolution of the Molten Salt Fast Reactor (MSFR). This promising GEN-IV nuclear reactor concept features peculiar characteristics such as the on-line fuel reprocessing, which prevents the use of commonly available burn-up codes. Besides, the presence of circulating nuclear fuel and radioactive streams from the core to the reprocessing plant requires a precise knowledge of the fuel isotopic composition during the plant operation. The developed extension of SERPENT-2 directly takes into account the effects of on-line fuel reprocessing on burn-up calculations and features a reactivity control algorithm. It is here assessed against a dedicated version of the deterministic ERANOS-based EQL3D procedure (PSI-Switzerland) and adopted to analyze the MSFR fuel salt isotopic evolution. Particular attention is devoted to study the effects of reprocessing time constants and efficiencies on the conversion ratio and the molar concentration of elements relevant for solubility issues (e.g., trivalent actinides and lanthanides). Quantities of interest for fuel handling and safety issues are investigated, including decay heat and activities of hazardous isotopes (neutron and high energy gamma emitters) in the core and in the reprocessing stream. The radiotoxicity generation is also analyzed for the MSFR nominal conditions. The production of helium and the depletion in tungsten content due to nuclear reactions are calculated for the nickel-based alloy selected as reactor structural material of the MSFR. These preliminary evaluations can be helpful in studying the radiation damage of both the primary salt container and the axial reflectors.

  13. Serpentoanisocladium sinense n. g., n. sp. (Digenea: Cryptogonimidae) from the eastern water snake Sinonatrix percarinata (Boulenger) (Serpentes: Colubridae) in Guizhou Province, China.

    PubMed

    Tkach, Vasyl V; Bush, Sarah E

    2010-07-01

    Serpentoanisocladium sinense n. g., n. sp. (Digenea: Cryptogonimidae) is described from the intestine of the eastern water snake Sinonatrix percarinata (Boulenger) (Serpentes: Colubridae) from Guizhou Province, China. This digenean is morphologically most similar to members of Anisocladium Looss, 1902 and, to a lesser extent, Anisocoelium Lühe, 1900, which are parasites of marine teleost fish in the Mediterranean and Black Seas. The new genus and species can be differentiated from the two known species of Anisocladium by the position of the vitellarium in relation to the gonads and seminal vesicle, a much longer oesophagus, a shorter caecum only reaching the anterior margin of the anterior testis, the presence of a muscular sucker-like gonotyl, the lack of circumoral spines and the peculiar position of the uterus, which is confined to the same half of the body as the longer caecum. The new genus and species can be differentiated from the only known species of Anisocoelium by the substantially higher body length to width ratio, a much longer oesophagus, the arrangement of the vitelline follicles, the postovarian versus pre-ovarian seminal receptacle, the presence of a well-defined muscular gonotyl and the length of the shorter caecum. A diagnosis of the new genus and a description of the new species are provided. This is the first cryptogonimid found in snakes from China and the first cryptogonimid reported from S. percarinata. PMID:20532852

  14. Body Size Evolution in Insular Speckled Rattlesnakes (Viperidae: Crotalus mitchellii)

    PubMed Central

    Meik, Jesse M.; Lawing, A. Michelle; Pires-daSilva, André

    2010-01-01

    Background Speckled rattlesnakes (Crotalus mitchellii) inhabit multiple islands off the coast of Baja California, Mexico. Two of the 14 known insular populations have been recognized as subspecies based primarily on body size divergence from putative mainland ancestral populations; however, a survey of body size variation from other islands occupied by these snakes has not been previously reported. We examined body size variation between island and mainland speckled rattlesnakes, and the relationship between body size and various island physical variables among 12 island populations. We also examined relative head size among giant, dwarfed, and mainland speckled rattlesnakes to determine whether allometric differences conformed to predictions of gape size (and indirectly body size) evolving in response to shifts in prey size. Methodology/Principal Findings Insular speckled rattlesnakes show considerable variation in body size when compared to mainland source subspecies. In addition to previously known instances of gigantism on Ángel de la Guarda and dwarfism on El Muerto, various degrees of body size decrease have occurred frequently in this taxon, with dwarfed rattlesnakes occurring mostly on small, recently isolated, land-bridge islands. Regression models using the Akaike information criterion (AIC) showed that mean SVL of insular populations was most strongly correlated with island area, suggesting the influence of selection for different body size optima for islands of different size. Allometric differences in head size of giant and dwarf rattlesnakes revealed patterns consistent with shifts to larger and smaller prey, respectively. Conclusions/Significance Our data provide the first example of a clear relationship between body size and island area in a squamate reptile species; among vertebrates this pattern has been previously documented in few insular mammals. This finding suggests that selection for body size is influenced by changes in community dynamics that are related to graded differences in area over what are otherwise similar bioclimatic conditions. We hypothesize that in this system shifts to larger prey, episodic saturation and depression of primary prey density, and predator release may have led to insular gigantism, and that shifts to smaller prey and increased reproductive efficiency in the presence of intense intraspecific competition may have led to insular dwarfism. PMID:20209105

  15. The Plumed Serpent and the Red Atlantis.

    ERIC Educational Resources Information Center

    Willard, William

    1988-01-01

    Examines work of author D.H. Lawrence and John Collier, later Bureau of Indian Affairs Commissioner, during 1920s when they stayed as Mabel Dodge Luhan's guests in Taos, New Mexico. Examines their perceptions of Pueblo Indian culture, federal-Indian relationship, and Indian influences on Lawrence's and Collier's work. (TES)

  16. Chemosensory age discrimination in the snake Boa constrictor (Serpentes: Boidae).

    PubMed

    Gabirot, Marianne; Picerno, Pablo; Valencia, Jorge; Lopez, Pilar; Martin, José

    2012-12-01

    Many snakes are able to use their chemosensory system to detect scent of conspecifics, which is important in many social contexts. Age discrimination based on chemical cues may be especially important to ensure access to sexually mature potential partners. In this study, we used 24 individual Boa constrictor snakes (12 adults mature and 12 non-mature individuals) that had been captured in different areas of Ecuador, and were maintained in captivity at the Vivarium of Quito. We used tongue-flick experiments to examine whether these snakes were able to discriminate between scents from mature and non-mature individuals. Results showed that B. constrictor snakes used chemical cues to recognize conspecifics and that the scent of individuals of different ages elicited chemosensory responses of different magnitudes. The scents from adult conspecifics elicited the quickest and highest chemosensory responses (i.e., short latency times and high tongue-flick rates), although we did not find differential responses to scent of males and females. The magnitude of the responses was lower to scent of sub adult individuals, and then even lower to scent of juvenile snakes, but in all cases the scent of snakes was discriminated from a blank control. We discuss the potential chemical mechanisms that may allow age recognition and its implications for social and sexual behavior of this snake species. PMID:23342514

  17. The complete mitochondrial genome of Elaphe bimaculata (Reptilia, Serpentes, Colubridae).

    PubMed

    Yan, Long; Geng, Zhang-Zhen; Yan, Peng; Wu, Xiao-Bing

    2016-03-01

    The Chinese leopard snake (Elaphe bimaculata) is an endemic species to China. The complete nucleotide sequence of the mitochondrial (mt) genome of E. bimaculata is determined in this study. The circle genome was 17,183 bp in length and consisted of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 2 duplicate control regions. Several peculiar features were observed in mitogenome of E. bimaculata, such as the translocation of tRNA(Leu(UUR)) gene and an incomplete copy for tRNA(Pro). PMID:25090378

  18. On the identity of Chironius flavolineatus (Serpentes: Colubridae).

    PubMed

    Hamdan, Breno; Scali, Stefano; Fernandes, Daniel Silva

    2014-01-01

    The snake genus Chironius Fitzinger, 1826 is endemic to the Neotropical region, occurring from Honduras to Uruguay and northeastern Argentina. Some species of the genus have taxonomic and/or nomenclatural problems, such as C. flavolineatus which lacks agreement in the literature about its authorship and type locality. Some researchers have been suggesting Jan (1863) as the author of the species since he first described C. flavolineatus based on two specimens. However, other researchers report that Jan's description is so incomplete that it is not possible to ascertain what snake he had in mind and therefore suggest Boettger (1885) as the author, since he was the first to provide a detailed description of the species. In the present study one of the syntypes of C. flavolineatus, supposedly destroyed in Second World War, was found. Thus, the taxonomic identity of C. flavolineatus was redefined, its lectotype was designated and the authorship of the taxa is attributed to Jan (1863). PMID:24870316

  19. The complete mitochondrial genome of Oocatochus rufodorsatus (Reptilia, Serpentes, Colubridae).

    PubMed

    Li, En; Feng, Dinglong; Yan, Peng; Xue, Hui; Chen, Jing; Wu, Xiao-Bing

    2014-12-01

    The complete mitochondrial genome from the red-backed ratsnake Oocatochus rufodorsatus was determined. The following four distinctive features are observed: duplicate control regions that have nearly identical sequences at two different locations of mitogenome, translocation of tRNA-Leu (UUR), a pseudogene for tRNA-Pro and truncations of T?C arm for most tRNA genes. PMID:23901930

  20. Uni-directional transport properties of a serpent billiard

    NASA Astrophysics Data System (ADS)

    Horvat, Martin; Prosen, Tomaz

    2004-03-01

    We present a dynamical analysis of a classical billiard chain—a channel with parallel semi-circular walls, which can serve as a model for a bent optical fibre. An interesting feature of this model is the fact that the phase space separates into two disjoint invariant components corresponding to the left and right uni-directional motions. Dynamics is decomposed into the jump map, a Poincaré map between the two ends of a basic cell, and the time function, travelling time across a basic cell of a point on a surface of section. The jump map has a mixed phase space where the relative sizes of the regular and chaotic components depend on the width of the channel. For a suitable value of this parameter, we can have almost fully chaotic phase space. We have studied numerically the Lyapunov exponents, time auto-correlation functions and diffusion of particles along the chain. As a result of the singularity of the time function, we obtain marginally normal diffusion after we subtract the average drift. The last result is also supported by some analytical arguments.

  1. Seasonal variation of Hepatozoon spp. (Apicomplexa, Hepatozoidae) parasitemia from Boa constrictor amarali (Serpentes, Boidae) and Hydrodynastes gigas (Serpentes, Colubridae).

    PubMed

    de Vieira Santos, Mariana Morena; O'Dwyer, Lucia Helena; da Silva, Reinaldo José

    2005-09-01

    The aim of this study was to evaluate the parasitemia variation of three Hepatozoon species in Brazilian snakes. This study was conducted between 2001 and 2003 and included Hepatozoon terzii from Boa constrictor amarali, and Hepatozoon migonei and Hepatozoon cyclagrasi from Hydrodynastes gigas. It was observed that the parasitemia tended to decrease in all three Hepatozoon species but the parasites were not eliminated. This data suggest that Hepatozoon infection may be similar to Toxoplasma gondii infection, in that it persists throughout host life. PMID:15999279

  2. Diversity-dependent cladogenesis throughout western Mexico: Evolutionary biogeography of rattlesnakes (Viperidae: Crotalinae: Crotalus and Sistrurus).

    PubMed

    Blair, Christopher; Sánchez-Ramírez, Santiago

    2016-04-01

    Rattlesnakes (Crotalus and Sistrurus) represent a radiation of approximately 42 species distributed throughout the New World from southern Canada to Argentina. Interest in this enigmatic group of snakes continues to accrue due, in part, to their ecomorphological diversity, contributions to global envenomations, and potential medicinal importance. Although the group has garnered substantial attention from systematists and evolutionary biologists for decades, little is still known regarding patterns of lineage diversification. In addition, few studies have statistically quantified broad-scale biogeographic patterns in rattlesnakes to ascertain how dispersal occurred throughout the New World, particularly among the different major biomes of the Americas. To examine diversification and biogeographic patterns in this group of snakes we assemble a multilocus data set consisting of over 6700bp encompassing three nuclear loci (NT-3, RAG-1, C-mos) and seven mitochondrial genes (12S, 16S, ATPase6, ATPase8, ND4, ND5, cytb). Fossil-calibrated phylogenetic and subsequent diversification rate analyses are implemented using maximum likelihood and Bayesian inference, to examine their evolutionary history and temporal dynamics of diversity. Based on ancestral area reconstructions we explore dispersal patterns throughout the New World. Cladogenesis occurred predominantly during the Miocene and Pliocene with only two divergences during the Pleistocene. Two different diversification rate models, advocating diversity-dependence, are strongly supported. These models indicate an early rapid radiation followed by a recent speciation rate decline. Biogeographic analyses suggest that the high elevation pine-oak forests of western Mexico served as a major speciation pump for the majority of lineages, with the desert biome of western North America colonized independently at least twice. All together, these results provide evidence for rapid diversification of rattlesnakes throughout the Mexican highlands during the Neogene, likely in response to continual orogenesis of Mexico's major mountain systems, followed by more recent dispersal into desert and tropical biomes. PMID:26802208

  3. A relict lineage and new species of green palm-pitviper (Squamata, Viperidae, Bothriechis) from the Chortís Highlands of Mesoamerica

    PubMed Central

    Townsend, Josiah H.; Medina-Flores, Melissa; Wilson, Larry David; Jadin, Robert C.; Austin, James D.

    2013-01-01

    Abstract A new species of palm-pitviper of the genus Bothriechis is described from Refugio de Vida Silvestre Texíguat in northern Honduras. The new species differs from congeners by having 19 dorsal scale rows at midbody, a bright green dorsal coloration in adults, the prelacunal scale fused to the second supralabial, and in representing a northern lineage that is sister to Bothriechis lateralis, which is distributed in Costa Rica and western Panama and is isolated from the new taxon by the Nicaraguan Depression. This represents the 15th endemic species occurring in Refugio de Vida Silvestre Texíguat, one of the richest herpetofaunal sites in Honduras, itself being the country with the highest degree of herpetofaunal endemism in Central America. We name this new species in honor of a Honduran conservationist slain in fighting against illegal logging, highlighting the sacrifices of rural activists in battling these issues and the critical importance of conservation in these areas. PMID:23794885

  4. A relict lineage and new species of green palm-pitviper (Squamata, Viperidae, Bothriechis) from the Chortís Highlands of Mesoamerica.

    PubMed

    Townsend, Josiah H; Medina-Flores, Melissa; Wilson, Larry David; Jadin, Robert C; Austin, James D

    2013-01-01

    A new species of palm-pitviper of the genus Bothriechis is described from Refugio de Vida Silvestre Texíguat in northern Honduras. The new species differs from congeners by having 19 dorsal scale rows at midbody, a bright green dorsal coloration in adults, the prelacunal scale fused to the second supralabial, and in representing a northern lineage that is sister to Bothriechis lateralis, which is distributed in Costa Rica and western Panama and is isolated from the new taxon by the Nicaraguan Depression. This represents the 15th endemic species occurring in Refugio de Vida Silvestre Texíguat, one of the richest herpetofaunal sites in Honduras, itself being the country with the highest degree of herpetofaunal endemism in Central America. We name this new species in honor of a Honduran conservationist slain in fighting against illegal logging, highlighting the sacrifices of rural activists in battling these issues and the critical importance of conservation in these areas. PMID:23794885

  5. First record of Porocephalus cf. clavatus (Pentastomida: Porocephalida) as a parasite on Bothrops asper (Squamata: Viperidae) in Costa Rica.

    PubMed

    Alvarado, G; Sánchez-Monge, A

    2015-11-01

    Pentastomids are parasites that infect respiratory cavities of vertebrates, they are pretty common but poorly known in wildlife veterinary. A Bothrops asper snake (Garman, 1884) was captured in the Caribbean region of Costa Rica and had its lung infested with pentastomids, identified as ca Porocephalus clavatus (Wyman, 1845). This represents the first record of Porocephalus (Humboldt, 1812) on B. asper as well as P. cf. clavatus in Costa Rica. Further studies are needed to clarify their taxonomic position, images and scanning electron microscopy photographs (SEM) of the specimens are given. PMID:26628232

  6. Reproductive cycle of free-living male Saharan sand vipers, Cerastes vipera (Viperidae) in the Negev desert, Israel.

    PubMed

    Sivan, Jaim; Kam, Michael; Hadad, Shlomo; Allan Degen, A; Rozenboim, Israel; Rosenstrauch, Avi

    2012-11-01

    The Saharan sand viper, Cerastes vipera (Linnaeus, 1758), is distributed in all Saharan countries, being confined to sand and dune systems. This relatively small snake, up to 35 cm, is nocturnal, is active from spring to autumn (April to October) and hibernates during the winter (November to March). We predicted that C. vipera would have peak plasma testosterone concentration at mating and that the vas deferens would contain abundant spermatozoa at that time. To test our predictions, we collected information on the time of mating and measured monthly testosterone concentration, testes size and testicular activity in free-living male C. vipera during its active period from April to October. Mating occurred only during spring. The pattern of plasma testosterone concentration, testes volume, seminiferous tubule diameter and spermatogenesis all followed the general pattern of high values in autumn and spring and low values in early summer. Our predictions were partially supported. There was a high plasma testosterone concentration at mating in spring and the vas deferens contained abundant spermatozoa, as predicted, but there was also a high plasma testosterone concentration in autumn without mating. We concluded that: (1) males are both aestival in that they produce spermatozoa in autumn, which they store over the winter hibernation period, and vernal in that they produce spermatozoa in spring prior to mating; (2) matings are associated with spermatogenesis; and (3) the high plasma testosterone concentration is concomitant with both matings and spermatogenesis in spring and with spermatogenesis in autumn. We propose that C. vipera has a single peak of testicular activity and plasma testosterone concentration which start in autumn and end in spring. We also propose that spermatogenesis is prior to spring mating and, consequently, is prenuptial. PMID:22967959

  7. Edema induced by Bothrops asper (Squamata: Viperidae) snake venom and its inhibition by Costa Rican plant extracts.

    PubMed

    Badilla, Beatriz; Chaves, Fernando; Mora, Gerardo; Poveda, Luis J

    2006-06-01

    We tested the capacity of leaf (Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, and Satureja viminea) and root (Uncaria tomentosa) extracts to inhibit edema induced by Bothrops asper snake venom. Edema-forming activity was studied plethysmographically in the rat hind paw model. Groups of rats were injected intraperitoneally with various doses of each extract and, one hour later, venom was injected subcutaneously in the right hind paw. Edema was assessed at various time intervals. The edematogenic activity was inhibited in those animals that received an injection U. tomentosa, C. nutans or L. speciosa extract. The extract of U. baccifera showed a slight inhibition of the venom effect. Extract from S. viminea and, to a lesser extent that of U. leptuphylla, induced a pro-inflammatory effect, increasing the edema at doses of 250 mg/kg at one and two hours. PMID:18494294

  8. Sexual activity and plasma levels of sex steroids in the aspic viper Vipera aspis L. (Reptilia, Viperidae).

    PubMed

    Saint Girons, H; Bradshaw, S D; Bradshaw, F J

    1993-09-01

    Reproductive behavior and associated sexual activity was studied in individual male and female Vipera aspis over a 3-year period in western France in an attempt to correlate mating behavior with blood levels of gonadal sex steroids. Males had higher average levels of both testosterone (T) and 5 alpha-dihydrotestosterone (DHT) than females. Levels of progesterone (P) did not differ significantly between the two sexes but estradiol-17 beta (E2) concentrations were significantly higher in females during the season of mating. Spring mating behavior and copulation in males was associated with significantly increased levels of T and DHT, compared with postmating males; and a similar, but not significant trend, was evident with autumnal mating. The only statistically significant hormonal difference detected in males showing no sexual activity in autumn, was an elevated level of E2 at 0.52 +/- 0.20 ng/ml compared with 0.09 +/- 0.03 ng/ml in spring-breeding males (P = 0.05). Estrus in females is associated with increased levels of all four steroids but significant only for E2 and DHT. Levels of P were significantly reduced in females displaying seasonal anestrous in the spring immediately following reproduction. Females not displaying estrus in either spring or autumn had significantly lower plasma DHT and E2. Although mating behavior in males is associated statistically with elevated levels of T and DHT, a tight correlation is not obvious at the individual level, suggesting that increased concentrations of androgens are a necessary, but not sufficient, condition for mating. The data from V. aspis suggest that, as in a number of other reptilian species, high circulating levels of androgens function to "condition" or "organize" sexual behavior in males which may be displayed at some later time, well after actual levels have fallen, thus engendering the impression that reproductive behavior may be temporally dissociated from essential hormonal stimuli. PMID:8224772

  9. Molecular evolution of Bov-B LINEs in vertebrates.

    PubMed

    Kordis, D; Gubensek, F

    1999-09-30

    Since their discovery in family Bovidae (bovids), Bov-B LINEs, believed to be order-specific SINEs, have been found in all ruminants and recently also in Viperidae snakes. The distribution and the evolutionary relationships of Bov-B LINEs provide an indication of their origin and evolutionary dynamics in different species. The evolutionary origin of Bov-B LINE elements has been shown unequivocally to be in Squamata (squamates). The horizontal transfer of Bov-B LINE elements in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The direction of horizontal transfer from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution of Bov-B LINE elements. The ancestor of Colubroidea snakes has been recognized as a possible donor of Bov-B LINE elements to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINE elements in Ruminantia and the fossil data of Ruminantia to be 40-50 My ago. The phylogenetic relationships of Bov-B LINE elements from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINE elements have been stably maintained by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:10570995

  10. Horizontal transfer of non-LTR retrotransposons in vertebrates.

    PubMed

    Kordis, D; Gubensek, F

    1999-01-01

    Since their discovery in family Bovidae (bovids), Bov-B LINEs, believed to be order-specific SINEs, have been found in all ruminants and recently also in Viperidae snakes. The distribution and the evolutionary relationships of Bov-B LINEs provide an indication of their origin and evolutionary dynamics in different species. The evolutionary origin of Bov-B LINE elements has been shown unequivocally to be in Squamata (squamates). The horizontal transfer of Bov-B LINE elements in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The direction of horizontal transfer from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution of Bov-B LINE elements. The ancestral snake lineage (Boidae) has been recognized as a possible donor of Bov-B LINE elements to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINE elements in Ruminantia and the fossil data of Ruminantia to be 40-50 mya. The phylogenetic relationships of Bov-B LINE elements from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINE elements have been stably maintained by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:10952205

  11. Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes.

    PubMed

    Kordis, D; Gubensek, F

    1998-09-01

    We have shown previously by Southern blot analysis that Bov-B long interspersed nuclear elements (LINEs) are present in different Viperidae snake species. To address the question as to whether Bov-B LINEs really have been transmitted horizontally between vertebrate classes, the analysis has been extended to a larger number of vertebrate, invertebrate, and plant species. In this paper, the evolutionary origin of Bov-B LINEs is shown unequivocally to be in Squamata. The previously proposed horizontal transfer of Bov-B LINEs in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The horizontal transfer of Bov-B LINEs from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution. The ancestor of Colubroidea snakes is a possible donor of Bov-B LINEs to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINEs in Ruminantia and the fossil data of Ruminantia to be 40-50 My ago. The phylogenetic relationships of Bov-B LINEs from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINEs have been maintained stably by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:9724768

  12. Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes

    PubMed Central

    Kordis, Dusan; Gubensek, Franc

    1998-01-01

    We have shown previously by Southern blot analysis that Bov-B long interspersed nuclear elements (LINEs) are present in different Viperidae snake species. To address the question as to whether Bov-B LINEs really have been transmitted horizontally between vertebrate classes, the analysis has been extended to a larger number of vertebrate, invertebrate, and plant species. In this paper, the evolutionary origin of Bov-B LINEs is shown unequivocally to be in Squamata. The previously proposed horizontal transfer of Bov-B LINEs in vertebrates has been confirmed by their discontinuous phylogenetic distribution in Squamata (Serpentes and two lizard infra-orders) as well as in Ruminantia, by the high level of nucleotide identity, and by their phylogenetic relationships. The horizontal transfer of Bov-B LINEs from Squamata to the ancestor of Ruminantia is evident from the genetic distances and discontinuous phylogenetic distribution. The ancestor of Colubroidea snakes is a possible donor of Bov-B LINEs to Ruminantia. The timing of horizontal transfer has been estimated from the distribution of Bov-B LINEs in Ruminantia and the fossil data of Ruminantia to be 40–50 My ago. The phylogenetic relationships of Bov-B LINEs from the various Squamata species agrees with that of the species phylogeny, suggesting that Bov-B LINEs have been maintained stably by vertical transmission since the origin of Squamata in the Mesozoic era. PMID:9724768

  13. Taxonomic status and morphological variation of Hydrodynastes bicinctus (Hermann, 1804) (Serpentes: Dipsadidae).

    PubMed

    Murta-Fonseca, Roberta A; Franco, Francisco L; Fernandes, Daniel Silva

    2015-01-01

    Hydrodynastes bicinctus was described with no type material or locality and it has two subspecies currently recognized that are not taxonomically well defined. We tested the validity of the two subspecies through meristic, morphometric, and color pattern characters. Two apparently distinct color patterns of H. bicinctus were noticed, one from the Cerrado open formations and the other from the Amazon rainforest. These aforementioned patterns, however, exhibited a high degree of geographic overlap and many specimens showed a blended pattern. Based on these results we propose synonymizing H. bicinctus schultzi with the nominal taxon. Furthermore, we designate a neotype for the species, present data on geographic distribution, and provide morphological descriptions of the hemipenis, cephalic glands, and skull. PMID:26623921

  14. Uncertainty propagation in full-core Monte Carlo depletion simulations using Serpent

    SciTech Connect

    Wyant, T.; Petrovic, B.

    2013-07-01

    The desire to accurately model the heterogeneity of the nuclear reactor environment combined with the ever more powerful computational resources have made in recent years the use of Monte Carlo method more attractive and feasible (if challenging) even for 3-D full core depletion simulation. However, in this case statistical uncertainty is combined with error propagating through the calculation from previous steps. In an effort to understand this error propagation, a numerical study was undertaken and previously reported modeling depletion of a four fuel assemblies (a 'quad'). This work extends results and analysis on a full nuclear reactor core depletion simulation where isotopics of individual fuel pins is tracked. By changing the code's initial random number seed, the data produced by a series of 19 replica runs was used to investigate the true and apparent variance in k{sub eff} and pin powers. It is hoped that this results can help to identify some common regularities in the behavior of uncertainty in several key parameters, and ultimately develop a predictive model. (authors)

  15. The Development of the Skull of the Egyptian Cobra Naja h. haje (Squamata: Serpentes: Elapidae)

    PubMed Central

    Khannoon, Eraqi R.; Evans, Susan E.

    2015-01-01

    Background The study of craniofacial development is important in understanding the ontogenetic processes behind morphological diversity. A complete morphological description of the embryonic skull development of the Egyptian cobra, Naja h. haje, is lacking and there has been little comparative discussion of skull development either among elapid snakes or between them and other snakes. Methodology/Principal Findings We present a description of skull development through a full sequence of developmental stages of the Egyptian cobra, and compare it to other snakes. Associated soft tissues of the head are noted where relevant. The first visible ossification centres are in the supratemporal, prearticular and surangular, with slight ossification visible in parts of the maxilla, prefrontal, and dentary. Epiotic centres of ossification are present in the supraoccipital, and the body of the supraoccipital forms from the tectum posterior not the tectum synoticum. The venom glands are visible as distinct bodies as early at stage 5 and enlarge later to extend from the otic capsule to the maxilla level with the anterior margin of the eye. The gland becomes more prominent shortly before hatching, concomitant with the development of the fangs. The tongue shows incipient forking at stage 5, and becomes fully bifid at stage 6. Conclusions/Significance We present the first detailed staging series of cranial development for the Egyptian cobra, Naja h. haje. This is one of the first studies since the classical works of G. de Beer and W. Parker that provides a detailed description of cranial development in an advanced snake species. It allows us to correct errors and misinterpretations in previous accounts which were based on a small sample of specimens of uncertain age. Our results highlight potentially significant variation in supraoccipital formation among squamates and the need for further research in this area. PMID:25860015

  16. The Serpent in the Garden State: Juvenile Delinquency in 1920s New Jersey

    ERIC Educational Resources Information Center

    Ferry, Thomas M.

    2010-01-01

    School administrators, educators, psychologists, social workers, the juvenile courts, institutional reformers, and others shape the manner in which children are labeled, portrayed, and treated. However, the agendas, motivations, political language, and influence of these "helping professionals" in "treating" and "reforming" juvenile delinquents…

  17. Phylogenetic position, origin and biogeography of Palearctic and Socotran blind-snakes (Serpentes: Typhlopidae).

    PubMed

    Kornilios, P; Giokas, S; Lymberakis, P; Sindaco, R

    2013-07-01

    The majority of the family Typhlopidae occurs in the Neotropic, Australasian, Indo-Malayan and Afrotropic ecoregions. They show a restricted distribution in the western Palearctic, where they include few native species, i.e. Rhinotyphlops simoni, R. episcopus and Typhlops vermicularis. A unique species among typhlopids is T. socotranus, found in Socotra, one of the most endemic-rich archipelagoes. In this study we determine the phylogenetic position of the above mentioned species and discuss their systematics, origin and biogeography. For this purpose we use three protein-coding nuclear markers (AMEL-amelogenin, BDNF-brain-derived neurotrophic factor and NT3-neurotrophin 3) to construct a time-calibrated phylogeny of the family Typhlopidae. Our results show that T. socotranus is a sister-species to T. vermicularis, while R. simoni and R. episcopus are sister-species to each other and are found within the African clade of the family, although they are geographically distributed in west Asia. Additionally we discuss several hypotheses on their origin, as well as the occurence of typhlopids in Eurasia. PMID:23523862

  18. Gaps and Serpents; Windows, Borders, and Mirrors: Merging of Analytical Tools from Mass and Interpersonal Communication.

    ERIC Educational Resources Information Center

    Burke, Ken

    Despite the obvious intersections between the studies of interpersonal and mass communication, an unnecessary separation exists between those two closely related (sub)disciplines. Two avenues of connection between these areas of study are the concepts of gap bridging, and application of visual analysis to conversation analysis. James Guardino has…

  19. Molecular systematics and undescribed diversity of Madagascan scolecophidian snakes (Squamata: Serpentes).

    PubMed

    Nagy, Zoltán T; Marion, Angela B; Glaw, Frank; Miralles, Aurélien; Nopper, Joachim; Vences, Miguel; Hedges, S Blair

    2015-01-01

    We provide an updated molecular phylogenetic analysis of global diversity of typhlopid and xenotyphlopid blindsnakes, adding a set of Madagascan samples and sequences of an additional mitochondrial gene to an existing supermatrix of nuclear and mitochondrial gene segments. Our data suggest monophyly of Madagascan typhlopids, exclusive of introduced Indotyphlops braminus. The Madagascar-endemic typhlopid clade includes two species previously assigned to the genus Lemuriatyphlops (in the subfamily Asiatyphlopinae), which were not each others closest relatives. This contradicts a previous study that described Lemuriatyphlops based on a sequence of the cytochrome oxidase subunit 1 gene from a single species and found this species not forming a clade with the other Malagasy species included. Based on our novel phylogenetic assessment we include all species in this endemic typhlopid clade in the genus Madatyphlops and in the subfamily Madatyphlopinae and consider Lemuriatyphlops as junior synonym. Within Madatyphlops, we identify several candidate species. For some of these (those in the M. arenarius complex), our preliminary data suggest sympatric occurrence and morphological differentiation, thus the existence of undescribed species. We also comment on the genus-level classification of several non-Madagascan typhlopids. We suggest that African species included in Madatyphlops (Afrotyphlops calabresii, A. cuneirostris, A. platyrhynchus, and Rhinotyphlops leucocephalus) should not be included in this genus. We furthermore argue that recent claims of Sundatyphlops, Antillotyphlops, and Cubatyphlops being "undiagnosable" or "not monophyletic" were based on errors in tree reconstruction and failure to notice diagnostic characters, and thus regard these three genera as valid. PMID:26624649

  20. Can we prevent doctors being complicit in torture? Breaking the serpent's egg.

    PubMed

    O'Connor, Mike

    2009-12-01

    A significant minority of the tortured prisoners who survive report that a doctor was present during their torture. Yet few medical practitioners are ever criminally prosecuted or even disciplined by their regulatory bodies. Can such gross violations of the Hippocratic Code be so easily ignored or are these doctors carefully shielded from detection and prosecution by a grateful state? Mostly doctors act to vet prisoners for their capacity to withstand the torture or resuscitate them to allow torture and interrogation to continue. However, on occasion, the "healers" may be the actual torturers as happened in Russian psychoprisons in the latter part of the 20th century. This article argues that the de facto immunity which complicit doctors currently appear to enjoy must be stripped away and replaced by effective processes to detect and then prosecute criminal behaviour. This will require widespread reporting of cases and action by international bodies, including non-government organisations. Prevention is clearly preferable and this will require improvements in undergraduate and graduate medical education about international humanitarian and human rights law. There is evidence that many medical faculties pay scant attention to this education and their students graduate with serious flaws in their understanding and attitudes towards human rights. Education should target "doctors at risk" in prisons, armed forces and the police. It should address professional behaviour which tolerates or even protects cultures of abuse. A code of professional conduct would assist "doctors at risk" to resist overtures for them to become complicit in torture, Medical Practice Acts should include statements on respecting human rights when defining good professional conduct. Doctors who become complicit in torture betray their profession. Swift action should be taken to stop such abuses and perpetrators should receive strong disciplinary action from regulatory bodies. PMID:20169802

  1. Is the Serpent Eating Its Tail? The Digital Divide and African Americans

    ERIC Educational Resources Information Center

    Horton, Jacqueline

    2004-01-01

    The Digital Divide is alive and well in America. What this means is the technology haves and the have-nots are continually growing further apart. Due to the pace of change in the field of computer technology, this divide widens faster in less time. Playing catch-up becomes an increasingly more difficult game to endure, with the government, public,…

  2. DISCOVERY OF THE MADAGASCAR SERPENT-EAGLE, EUTRIORCHIS ASTUR, IN CENTRAL AND SOUTHEASTERN MADAGASCAR. (U915543)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. [Early Stages of Skull Embryogenesis in the Grass Snake, Natrix natrix (Serpentes, Colubridae)].

    PubMed

    Kovtun, M F; Sheverdyukova, H V

    2015-01-01

    Studies of previous authors on snake skull embryogenesis have been performed on embryos obtained from eggs after oviposition. The aim of this study was to investigate the initial stages of chondrocranium development in Grass-snake Natrixnatrix Linnaeus, 1758, embryos before oviposition. Natrix natrix embryos at early developmental stages (24-27 according to the table of normal development by D. Zehr (1962)) were obtained by means of caesarean section. At developmental stages 25-27, previously undescribed structures were found in the region of future skull formation. These structures exist during one or two stages and then disappear. Therefore, we call them "temporary structures." The assumption about the nature of these structures is based on their topography and comparison with the structures of developing or fully formed chondrocranium in other vertebrates. It is hypothesized that the temporary structures in Natrix natrix chondrocranium are vestiges ofprimary chondrocranium of ancestral vertebrate forms, and they indicate the existence of several variants in the formation of chondrocranium in the historical vertebrates.' development. PMID:26480486

  4. A new species of Chironius Fitzinger, 1826 from the state of Bahia, Northeastern Brazil (Serpentes: Colubridae).

    PubMed

    Fernandes, Daniel Silva; Hamdan, Breno

    2014-01-01

    We describe a new species of Chironius Fitzinger, 1826 from the highlands of Chapada Diamantina, state of Bahia, Brazil. The new species is distinguished from all currently recognized congeners by a unique combination of states of characters on coloration, scale counts, scale ornamentation, and hemipenis. The new species closely resembles Chironius flavolineatus (Jan, 1863) in color pattern, but differs from the later taxon by the presence of two to four posterior temporal scales; cloacal shield entire; six to ten rows of keeled dorsal scales at midbody; ventral scales with posterior dark edges forming conspicuous transverse bars along almost the entire venter; conspicuous dark longitudinal stripes (in "zigzag") in the midventral portion of subcaudals; region of medial constriction of hemipenis slightly covered with spinules separating calyces of apex from spines below region of constriction; and sulcus spermaticus situated on convex face of hemipenis in lateral view. The new species is apparently restricted to Chapada Diamantina, corroborating the biological importance of this region from a conservational perspective. PMID:25543653

  5. Unusual labial glands in snakes of the genus Geophis Wagler, 1830 (Serpentes: Dipsadinae).

    PubMed

    de Oliveira, Leonardo; da Costa Prudente, Ana Lúcia; Zaher, Hussam

    2014-01-01

    Geophis belongs to the goo-eating dipsadine assemblage of snakes that are known to feed exclusively on earthworms, snails, and slugs. Although the unusual feeding strategies of the goo-eating dipsadines are well known (but poorly documented), little attention has been paid to their internal anatomy. Here, we describe a new and noteworthy morphological and histochemical condition of the infralabial glands in three species of Geophis (G. brachycephalus, G. nasalis and G. semidoliatus), all earthworm feeders. Their infralabial glands are constituted of two distinct parts: an anterolateral portion composed of mucous and seromucous cells that stretches from the tip of the dentary to the corner of the mouth, and a tubular posteromedial portion that is exclusively seromucous. The anterolateral portion receives fibers of the levator anguli oris muscle that attaches on its posterodorsal extremity while the posteromedial portion extends posteriorly to the corner of the mouth where it receives fibers of the adductor mandibulae externus medialis muscle. Furthermore, the posteromedial portion of the infralabial gland is constituted by large acini filled with secretion that is periodic acid-Schiff positive. These acini release their secretion directly into a large lumen located in the middle of the glandular portion. In the three species examined, the supralabial glands show a traditional configuration, being constituted of mucous and seromucous cells and retaining an enlarged part in its caudal region that resembles a Duvernoy's gland. The presence in Geophis of an expanded lumen in part of the infralabial gland that is compressed by an adjacent muscle suggests a more specialized role for the secretion produced by these glands that may not be related to envenomation but rather to prey transport and mucus control. PMID:24127255

  6. A new species of Rhadinella (Serpentes: Colubridae) from the Pacific versant of Oaxaca, Mexico.

    PubMed

    Campbell, Jonathan A

    2015-01-01

    I describe a new species of Rhadinella from the Pacific versant of Oaxaca, Mexico, a region where the genus was previously unknown. This diminutive snake is a member of a group of snakes that have dark dorsal coloration, which mostly or completely obfuscates a pattern of longitudinal striping characteristic of most species of Rhadinella. The closest relative of the new species, on the basis of morphological similarities, appears to be Rhadinella pilonaorum which occurs to the east of the Isthmus of Tehuantepec about 800 km from the type-locality of the new species. PMID:25781099

  7. Morphological variation and affinities of the poorly known snake Atractus caxiuana (Serpentes: Dipsadidae) .

    PubMed

    Passos, Paulo; Ramos, Luciana O; Pinna, Pedro H; Prudente, Ana L C

    2013-01-01

    Atractus caxiuana was recently described based on three specimens (two males and one female) from the Floresta Nacional de Caxiuanã, municipality of Melgaço, state of Pará, in the eastern portion of the Brazilian Amazon. Apart from the type series, no additional samples are known for the species. In this study, we report new specimens of A. caxiuana, providing new morphological data (meristic, morphometric, pholidosis, colour pattern, and hemipenis) and localities. We relate the variability displayed by the characters analyzed to sexual dimorphism, geographic variation, and ontogeny. Additionally, we provide detailed comparisons with A. collaris and putative sister species, and propose a new species group to accommodate this distinct and possible monophyletic assemblage.  PMID:25113336

  8. Leptophis santamartensis (Serpentes, Colubridae), a junior synonym of Leptophis ahaetulla occidentalis

    USGS Publications Warehouse

    Albuquerque, Nelson R.; de Passos, Paulo; Gotte, Steve W.

    2012-01-01

    Leptophis santamartensis, known only from Sierra Nevada de Santa Marta, Colombia, is one of the more poorly known species of the genus Leptophis. The characters used for its diagnosis largely overlap with those of other Leptophis, mainly with Leptophis ahaetulla occidentalis, the only other Leptophis known to occur in the Sierra Nevada de Santa Marta. A detailed comparison of L. a. occidentalis with the two known specimens of L. santamartensis leads to the conclusion that the latter should be relegated to the synonymy of the former.

  9. Monsters of the sea serpent: parasites of an oarfish, Regalecus russellii.

    PubMed

    Kuris, Armand M; Jaramillo, Alejandra G; McLaughlin, John P; Weinstein, Sara B; Garcia-Vedrenne, Ana E; Poinar, George O; Pickering, Maria; Steinauer, Michelle L; Espinoza, Magaly; Ashford, Jacob E; Dunn, Gabriela L P

    2015-02-01

    Examination of a small portion of the viscera of an oarfish ( Regalecus russellii ) recovered from Santa Catalina Island, southern California, revealed numerous tetraphyllidean tapeworm plerocercoids, Clistobothrium cf. montaukensis; 2 juvenile nematodes, Contracaecum sp.; and a fragment of an adult acanthocephalan, family Arhythmacanthidae. This suggests that the fish was relatively heavily parasitized. The presence of larval and juvenile worms suggests that oarfish are preyed upon by deep-swimming predators such as the shortfin mako shark, Isurus oxyrinchus , known to be a definitive host for the adult tapeworm, and also by diving mammals such as sperm whales, Physeter catodon L., hosts of Contracaecum spp. nematodes. PMID:25220829

  10. Unique features of myogenesis in Egyptian cobra (Naja haje) (Squamata: Serpentes: Elapidae).

    PubMed

    Khannoon, Eraqi R; Rupik, Weronika; Lewandowski, Damian; Dubińska-Magiera, Magda; Swadźba, Elwira; Daczewska, Małgorzata

    2016-03-01

    During early stages of myotomal myogenesis, the myotome of Egyptian cobra (Naja haje) is composed of homogenous populations of mononucleated primary myotubes. At later developmental phase, primary myotubes are accompanied by closely adhering mononucleated cells. Based on localization and morphology, we assume that mononucleated cells share features with satellite cells involved in muscle growth. An indirect morphological evidence of the fusion of mononucleated cells with myotubes is the presence of numerous vesicles in the subsarcolemmal region of myotubes adjacent to mononucleated cell. As differentiation proceeded, secondary muscle fibres appeared with considerably smaller diameter as compared to primary muscle fibre. Studies on N. haje myotomal myogenesis revealed some unique features of muscle differentiation. TEM analysis showed in the N. haje myotomes two classes of muscle fibres. The first class was characterized by typical for fast muscle fibres regular distribution of myofibrils which fill the whole volume of muscle fibre sarcoplasm. White muscle fibres in studied species were a prominent group of muscles in the myotome. The second class showed tightly paced myofibrils surrounding the centrally located nucleus accompanied by numerous vesicles of different diameter. The sarcoplasm of these cells was characterized by numerous lipid droplets. Based on morphological features, we believe that muscle capable of lipid storage belong to slow muscle fibres and the presence of lipid droplets in the sarcoplasm of these muscles during myogenesis might be a crucial adaptive mechanisms for subsequent hibernation in adults. This phenomenon was, for the first time, described in studies on N. haje myogenesis. PMID:26025263

  11. Codes of professional conduct for Australian Defence Force military physicians: evenomating the serpent?

    PubMed

    O'Connor, Mike

    2010-09-01

    The scandal of health professionals' involvement in recent human rights abuses in United States military detention centres has prompted concern that Australian military physicians should be well protected against similar pressures to participate in harsh interrogations. A framework of military health ethics has been proposed. Would a code of professional conduct be a partial solution? This article examines the utility of professional codes: can they transform unethical behaviour or are they only of value to those who already behave ethically? How should such codes be designed, what support mechanisms should be in place and how should complaints be managed? A key recommendation is that codes of professional conduct should be accompanied by publicly transparent procedures for the investigation of serious infractions and appropriate disciplinary action when proven. The training of military physicians should also aim to develop a sound understanding of both humanitarian and human rights law. At present, both civil and military education of physicians generally lacks any component of human rights law. The Australian Defence Force (ADF) seems well placed to add codes of professional conduct to its existing ethical framework because of strong support at the highest executive levels. PMID:20977165

  12. A new species of death adder (Acanthophis: Serpentes: Elapidae) from north-western Australia.

    PubMed

    Maddock, Simon T; Ellis, Ryan J; Doughty, Paul; Smith, Lawrence A; Wüster, Wolfgang

    2015-01-01

    Australian death adders (genus Acanthophis) are highly venomous snakes with conservative morphology and sit-and-wait predatory habits, with only moderate taxonomic diversity that nevertheless remains incompletely understood. Analyses of mitochondrial and nuclear gene sequences and morphological characteristics of death adders in northern Australia reveal the existence of a new species from the Kimberley region of Western Australia and the Northern Territory, which we describe as Acanthophis cryptamydros sp. nov. Although populations from the Kimberley were previously considered conspecific with Northern Territory death adders of the A. rugosus complex, our mtDNA analysis indicates that its closest relatives are desert death adders, A. pyrrhus. We found that A. cryptamydros sp. nov. is distinct in both mtDNA and nDNA analysis, and possesses multiple morphological characteristics that allow it to be distinguished from all other Acanthophis species. This study further supports the Kimberley region as an area with high endemic biodiversity. PMID:26623813

  13. Serpents in the Garden: English Professors in Contemporary Film and Television

    ERIC Educational Resources Information Center

    Carens, Timothy L.

    2010-01-01

    In an article on "Smart People" (2008), a film in which Dennis Quaid plays an English professor who becomes romantically involved with a former student, Jeffery J. Williams notes that a "common complaint among academics is that films don't depict them correctly, and in some ways Quaid was accoutered by central casting, beginning the movie in a…

  14. Kleptothermy: an additional category of thermoregulation, and a possible example in sea kraits (Laticauda laticaudata, Serpentes).

    PubMed

    Brischoux, François; Bonnet, Xavier; Shine, Richard

    2009-12-23

    Lacking the capacity for thermogenesis, most ectotherms inhabiting thermally heterogeneous environments rely instead upon exploiting that ambient heterogeneity. In many cases they maintain body temperatures within a narrow range despite massive spatial and temporal variation in ambient conditions. Reliance on diverse thermal opportunities is reflected in specific terms for organisms that bask in sunlight to regulate their temperature (heliotherms), or that press their bodies against warm substrates to facilitate heat flow (thigmotherms), or that rely on large body mass to maintain thermal constancy (gigantothermy). We propose an additional category of thermoregulators: kleptotherms, which regulate their own temperature by 'stealing' heat from other organisms. This concept involves two major conditions: the thermal heterogeneity created by the presence of a warm organism in a cool environment and the selective use of that heterogeneity by another animal to maintain body temperatures at higher (and more stable) levels than would be possible elsewhere in the local area. Kleptothermy occurs in endotherms also, but is usually reciprocal (rather than unilateral as in ectotherms). Thermal monitoring on a small tropical island documents a possible example of kleptothermy, based on high stable temperatures of a sea snake (Laticauda laticaudata) inside a burrow occupied by seabirds. PMID:19656862

  15. Morphological variation and taxonomy of Atractus latifrons (Günther, 1868) (Serpentes: Dipsadidae).

    PubMed

    Almeida, Paula C; Feitosa, Darlan T; Passos, Paulo; Prudente, Ana L C

    2014-01-01

    As currently understood Atractus latifrons is widely distributed in South America, occurring from Suriname to the east of the Andes in Bolivia. Throughout this widespread distribution, at least three distinct color patterns were previously reported in the literature. Here, we test whether quantitative variation and qualitative distribution of morphological characters are correlated with any color pattern displayed by the species along its range. We recognize three aposematic color patterns (bicolor in monads, tricolor in dyads, and tricolor in tetrads) for A. latifrons. We found no obvious correspondence between these patterns and any character systems analyzed herein. Additionally, we redescribe the holotype of A. latifrons and report on morphological variability (meristics, morphometrics, color patterns, and hemipenis) and geographical distribution (extending its distribution to the state Roraima, Brazil) of the species.  PMID:25283190

  16. The proper name of the neotropical tree boa often referred to as Corallus enhydris (Serpentes: Boidae)

    USGS Publications Warehouse

    McDiarmid, R.W.; Toure, T.; Savage, J.M.

    1996-01-01

    Confusion regarding the application of the proper scientific name for the common Neotropical tree boa has existed since Linnaeus described Boa enydris and Boa hortulana in 1758. We review the nomenclatural history of the species and point out the misapplication of scientific names that have characterized this form. Our review indicates that the proper scientific name for this highly variable, wide-ranging arboreal boid is Corallus hortulanus, not Corallus enydris, as has been used so frequently in recent years.

  17. Scratch resistance of the ventral skin surface in four snake species (Squamata, Serpentes).

    PubMed

    Klein, Marie-Christin G; Gorb, Stanislav N

    2016-04-01

    Snakes are limbless tetrapods highly specialized for sliding locomotion on various substrates. Their skin is constantly exposed to high friction forces, which promotes abrasion. Snake skin has material and surface specializations, presumably optimized for friction and abrasion resistance. We found that different snake species living in different habitats have different abrasion patterns and hypothesized that this correlates with specific epidermal architecture and surface topography. To test this hypothesis artificial scratches, under controlled load conditions, were created on the ventral skin material (epidermis) of four snake species adapted to different habitats: Lampropeltis getula californiae (stony and sandy soil substrates), Epicrates cenchria cenchria (trees, soil and water), Morelia viridis (trees), and Gongylophis colubrinus (burrowing in sand). Abrasion appearance on the skin surface was examined using scanning electron microscopy and white light interferometry. The material failure was different between the species, which we attribute to differences in the epidermis' response to the same abrasive challenge. We also discuss abrasion resistance mechanisms and the correlation with the different ultrastructure and surface microstructure. PMID:26874374

  18. Serpents in the Garden: English Professors in Contemporary Film and Television

    ERIC Educational Resources Information Center

    Carens, Timothy L.

    2010-01-01

    In an article on "Smart People" (2008), a film in which Dennis Quaid plays an English professor who becomes romantically involved with a former student, Jeffery J. Williams notes that a "common complaint among academics is that films don't depict them correctly, and in some ways Quaid was accoutered by central casting, beginning the movie in a…

  19. The Serpent in the Garden State: Juvenile Delinquency in 1920s New Jersey

    ERIC Educational Resources Information Center

    Ferry, Thomas M.

    2010-01-01

    School administrators, educators, psychologists, social workers, the juvenile courts, institutional reformers, and others shape the manner in which children are labeled, portrayed, and treated. However, the agendas, motivations, political language, and influence of these "helping professionals" in "treating" and "reforming" juvenile delinquents…

  20. Valid or not? Yunnan mountain snake Plagiopholis unipostocularis (Serpentes: Colubridae: Pseudoxenodontinae).

    PubMed

    Zhong, Guang Hui; Chen, Wen De; Liu, Qin; Zhu, Fei; Peng, Pei Hao; Guo, Peng

    2015-01-01

    Plagiopholis unipostocularis Zhao, Jiang & Huang, 1978 is a small snake endemic to Yunnan, southern China. Its validity is still controversial and unresolved. Based on extensive sampling in Yunnan, we conducted morphological comparison and molecular phylogenetics on the unidentified specimens of Plagiopholis from Yunnan. Based on a combination of morphological comparison and molecular phylogeny, the newly collected specimens could be identified as P. blakewayi. While some specimens exhibit one or more diagnostics of P. unipostocularis, and some characteristics are intermediate between that of Plagiopholis unipostocularis and P. blakewayi. Thus morphological continuities between two species uncovered P. unipostocularis is a synonymy of P. blakewayi, and the diagnostics of this species was revised accordingly. PMID:26624106

  1. Taxonomic revision of Chironius flavolineatus (Jan, 1863) with description of a new species (Serpentes: Colubridae).

    PubMed

    Hamdan, Breno; Fernandes, Daniel S

    2015-01-01

    We conducted a taxonomic review of Chironius flavolineatus on the basis of continuous and discrete morphological characters. We recognize a new species which is distinguished from all currently recognized congeners by the following unique combination of characters: first third of body black or dark gray; vertebral stripe yellowish or creamish white distinct from dorsals of nape and extending throughout almost whole body length; head dorsum tan to brown, distinct from background color of first third of body; posterior temporal scales ranging one to four; cloacal shield frequently divided; two to four rows of keeled dorsal scales at midbody; venter ground color gradually darkening towards cloaca; region of medial constriction of hemipenis slightly covered with spinules separating calyces of apex from spines below region of constriction; in lateral view, sulcus spermaticus positioned on convex face of hemipenis; ascending process of premaxilla oblique anteroposteriorly to longitudinal axis of skull; optic fenestrae not exceeding frontoparietal suture; posterior border of supratemporal exceeding braincase; dorsoventral axis of quadrate oblique mesolaterally, moving away from longitudinal axis of skull. Furthermore, we provide data on morphological variation, distribution, and an emended diagnosis for C. flavolineatus. PMID:26623847

  2. The Serpent Strikes: Simulation in a Large First-Year Course.

    ERIC Educational Resources Information Center

    Schrag, Philip G.

    1989-01-01

    A year-long simulation of a single case supplements a traditional civil procedure course at Georgetown University. Experience with the approach suggests that design features can reduce the burdens on the instructor without reducing course effectiveness, making the approach feasible even with larger classes. (MSE)

  3. On the systematics of Trimeresurus labialis Fitzinger in Steindachner, 1867, a pitviper from the Nicobar Islands (India), with revalidation of Trimeresurus mutabilis Stoliczka, 1870 (Squamata, Viperidae, Crotalinae).

    PubMed

    Vogel, Gernot; David, Patrick; Chandramouli, S R

    2014-01-01

    The Asian pitviper currently identified as Trimeresurus labialis Fitzinger in Steindachner, 1867 is revised on the basis of morphological data obtained from 37 preserved specimens originating from seven islands of the Nicobar Islands. Multivariate analyses shows that these specimens can be divided into two clusters of populations which differ by a series of constant taxonomically informative morphological characters. The first cluster, which includes the name-bearing types of Trimeresurus labialis Fitzinger in Steindachner, 1867, is present only on Car Nicobar Island. The second cluster, which includes the name-bearing types of Trimeresurus mutabilis Stoliczka, 1870, is distributed on the Central Nicobar Islands. We regard these clusters as distinct species, which are morphologically diagnosable and isolated from each other. As a consequence, Trimeresurus mutabilis, long considered a synonym of T. labialis, is here resurrected to specific level. A lectotype is designated for Trimeresurus mutabilis. PMID:24869554

  4. Food resources influence spatial ecology, habitat selection, and foraging behavior in an ambush-hunting snake (Viperidae: Bothrops asper): an experimental study.

    PubMed

    Wasko, Dennis K; Sasa, Mahmood

    2012-06-01

    Prey availability affects many aspects of predators' life history and is considered a primary factor influencing individuals' decisions regarding spatial ecology and behavior, but few experimental data are currently available. Snakes may represent ideal model organisms relative to other animal groups for addressing such resource dependency, due to a presumably more direct link between food resources and many aspects of behavior and natural history. We experimentally investigated the relationship between food intake and spatial behavior in a population of the snake Bothrops asper in a Costa Rican lowland rainforest. Six adult snakes were allowed to forage naturally while six were offered supplemental food in the field, with both groups monitored using radiotelemetry. Mean home range size did not differ between groups presumably due to small sample size, but supplementally fed snakes demonstrated altered patterns of macro- and microhabitat selection, shorter and less frequent movements, and increased mass acquisition. Fed snakes also devoted less time to foraging efforts, instead more frequently remaining inactive and utilizing shelter. Because snakes were always fed in situ and not at designated feeding stations, observed shifts in habitat selection are not explained by animals simply moving to areas of higher food availability. Rather, B. asper may have moved to swamps in order to feed on amphibians when necessary, but remained in preferred forest habitat when food was otherwise abundant. The strong behavioral and spatiotemporal responses of snakes in this population may have been influenced by an overall scarcity of mammalian prey during the study period. PMID:22440190

  5. Comparative study of anticoagulant and procoagulant properties of 28 snake venoms from families Elapidae, Viperidae, and purified Russell's viper venom-factor X activator (RVV-X).

    PubMed

    Suntravat, Montamas; Nuchprayoon, Issarang; Pérez, John C

    2010-09-15

    Snake venoms consist of numerous molecules with diverse biological functions used for capturing prey. Each component of venom has a specific target, and alters the biological function of its target. Once these molecules are identified, characterized, and cloned; they could have medical applications. The activated clotting time (ACT) and clot rate were used for screening procoagulant and anticoagulant properties of 28 snake venoms. Crude venoms from Daboia russellii siamensis, Bothrops asper, Bothrops moojeni, and one Crotalus oreganus helleri from Wrightwood, CA, had procoagulant activity. These venoms induced a significant shortening of the ACT and showed a significant increase in the clot rate when compared to the negative control. Factor X activator activity was also measured in 28 venoms, and D. r. siamensis venom was 5-6 times higher than those of B. asper, B. moojeni, and C. o. helleri from Wrightwood County. Russell's viper venom-factor X activator (RVV-X) was purified from D. r. siamensis venom, and then procoagulant activity was evaluated by the ACT and clot rate. Other venoms, Crotalus atrox and two Naja pallida, had anticoagulant activity. A significant increase in the ACT and a significant decrease in the clot rate were observed after the addition of these venoms; therefore, the venoms were considered to have anticoagulant activity. Venoms from the same species did not always have the same ACT and clot rate profiles, but the profiles were an excellent way to identify procoagulant and anticoagulant activities in snake venoms. PMID:20677373

  6. Comparative venom gland transcriptome surveys of the saw-scaled vipers (Viperidae: Echis) reveal substantial intra-family gene diversity and novel venom transcripts

    PubMed Central

    2009-01-01

    Background Venom variation occurs at all taxonomical levels and can impact significantly upon the clinical manifestations and efficacy of antivenom therapy following snakebite. Variation in snake venom composition is thought to be subject to strong natural selection as a result of adaptation towards specific diets. Members of the medically important genus Echis exhibit considerable variation in venom composition, which has been demonstrated to co-evolve with evolutionary shifts in diet. We adopt a venom gland transcriptome approach in order to investigate the diversity of toxins in the genus and elucidate the mechanisms which result in prey-specific adaptations of venom composition. Results Venom gland transcriptomes were created for E. pyramidum leakeyi, E. coloratus and E. carinatus sochureki by sequencing ~1000 expressed sequence tags from venom gland cDNA libraries. A standardised methodology allowed a comprehensive intra-genus comparison of the venom gland profiles to be undertaken, including the previously described E. ocellatus transcriptome. Blast annotation revealed the presence of snake venom metalloproteinases, C-type lectins, group II phopholipases A2, serine proteases, L-amino oxidases and growth factors in all transcriptomes throughout the genus. Transcripts encoding disintegrins, cysteine-rich secretory proteins and hyaluronidases were obtained from at least one, but not all, species. A representative group of novel venom transcripts exhibiting similarity to lysosomal acid lipase were identified from the E. coloratus transcriptome, whilst novel metallopeptidases exhibiting similarity to neprilysin and dipeptidyl peptidase III were identified from E. p. leakeyi and E. coloratus respectively. Conclusion The comparison of Echis venom gland transcriptomes revealed substantial intrageneric venom variation in representations and cluster numbers of the most abundant venom toxin families. The expression profiles of established toxin groups exhibit little obvious association with venom-related adaptations to diet described from this genus. We suggest therefore that alterations in isoform diversity or transcript expression levels within the major venom protein families are likely to be responsible for prey specificity, rather than differences in the representation of entire toxin families or the recruitment of novel toxin families, although the recruitment of lysosomal acid lipase as a response to vertebrate feeding cannot be excluded. Evidence of marked intrageneric venom variation within the medically important genus Echis strongly advocates further investigations into the medical significance of venom variation in this genus and its impact upon antivenom therapy. PMID:19948012

  7. Comparative study of anticoagulant and procoagulant properties of 28 snake venoms from families Elapidae, Viperidae, and purified Russell's viper venom-factor X activator (RVV-X).

    PubMed

    Suntravat, Montamas; Nuchprayoon, Issarang; Pérez, John C

    2010-06-01

    Snake venoms consist of numerous molecules with diverse biological functions used for capturing prey. Each component of venom has a specific target, and alters the biological function of its target. Once these molecules are identified, characterized, and cloned; they could have medical applications. The activated clotting time (ACT) and clot rate were used for screening procoagulant and anticoagulant properties of 28 snake venoms. Crude venoms from Daboia russellii siamensis, Bothrops asper, Bothrops moojeni, and one Crotalus oreganus helleri from Wrightwood, CA, had procoagulant activity. These venoms induced a significant shortening of the ACT and showed a significant increase in the clot rate when compared to the negative control. Factor X activator activity was also measured in 28 venoms, and D. r. siamensis venom was 5-6 times higher than those of B. asper, B. moojeni, and C. o. helleri from Wrightwood County. Russell's viper venom-factor X activator (RVV-X) was purified from D. r. siamensis venom, and then procoagulant activity was evaluated by the ACT and clot rate. Other venoms, Crotalus atrox and two Naja pallida, had anticoagulant activity. A significant increase in the ACT and a significant decrease in the clot rate were observed after the addition of these venoms; therefore, the venoms were considered to have anticoagulant activity. Venoms from the same species did not always have the same ACT and clot rate profiles, but the profiles were an excellent way to identify procoagulant and anticoagulant activities in snake venoms. PMID:20685219

  8. Annual cycles in plasma testosterone and thyroxine in the male aspic viper Vipera aspis L., (Reptilia, Viperidae), in relation to the sexual cycle and hibernation.

    PubMed

    Naulleau, G; Fleury, F; Boissin, J

    1987-02-01

    Blood samples were taken monthly from males of Vipera aspis kept in outdoor terraria. Plasma testosterone was estimated by radioimmunoassay and plasma thyroxine by the technique of isotopic competition, between October 1979 and September 1985. Plasma testosterone showed an annual bimodal profile. The highest peak was observed from February 15 to the end of March. 2 to 5 weeks after the first emergence from hibernation. Values then decreased greatly, to reach a minimum level when the vernal spermiogenesis was at its maximum. The secondary peak of plasma testosterone was lower and less well marked. It occurred at the end of summer, during the strongest spermiogenesis, and preceded the autumnal facultative mating period. Plasma thyroxine was at a maximum concentration from February to March after which levels decreased markedly. The seasonal profile of plasma thyroxine was clearly marked during the period of hibernation. From September to October, 2 months before the beginning of hibernation, thyroxine levels began to decrease, and they reached a minimum in November-December. Endocrine reactivation of the thyroid appeared at the end of hibernation. However, in contrast to the plasma testosterone, endocrine activity of the thyroid began 2 to 3 weeks before the end of hibernation. Mechanisms of reactivation for testicular and thyroidal endocrine structures are discussed. PMID:3817449

  9. A new species of Hepatozoon (Apicomplexa: Adeleorina) from Python regius (Serpentes: Pythonidae) and its experimental transmission by a mosquito vector.

    PubMed

    Sloboda, Michal; Kamler, Martin; Bulantová, Jana; Votýpka, Jan; Modrý, David

    2007-10-01

    Hepatozoon ayorgbor n. sp. is described from specimens of Python regius imported from Ghana. Gametocytes were found in the peripheral blood of 43 of 55 snakes examined. Localization of gametocytes was mainly inside the erythrocytes; free gametocytes were found in 15 (34.9%) positive specimens. Infections of laboratory-reared Culex quinquefasciatus feeding on infected snakes, as well as experimental infection of juvenile Python regius by ingestion of infected mosquitoes, were performed to complete the life cycle. Similarly, transmission to different snake species (Boa constrictor and Lamprophis fuliginosus) and lizards (Lepidodactylus lugubris) was performed to assess the host specificity. Isolates were compared with Hepatozoon species from sub-Saharan reptiles and described as a new species based on the morphology, phylogenetic analysis, and a complete life cycle. PMID:18163356

  10. Annotated checklist of the recent and extinct pythons (Serpentes, Pythonidae), with notes on nomenclature, taxonomy, and distribution

    PubMed Central

    Schleip, Wulf D.; O’Shea, Mark

    2010-01-01

    Abstract McDiarmid et al. (1999) published the first part of their planned taxonomic catalog of the snakes of the world. Since then, several new python taxa have been described in both the scientific literature and non-peer-reviewed publications. This checklist evaluates the nomenclatural status of the names and discusses the taxonomic status of the new taxa, and aims to continue the work of McDiarmid et al. (1999) for the family Pythonidae, covering the period 1999 to 2010. Numerous new taxa are listed, and where appropriate recent synonymies are included and annotations are made. A checklist and a taxonomic identification key of valid taxa are provided. PMID:21594030

  11. The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: Two new species of Ramphotyphlops from the Caroline Islands

    USGS Publications Warehouse

    Wynn, A.H.; Reynolds, R.P.; Buden, D.W.; Falanruw, M.; Lynch, B.

    2012-01-01

    Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R. adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excluding Ramphotyphlops braminus). Both species are unusual in being known only from small, low-lying atolls. They can be distinguished from other Ramphotyphlops by the combination of 22 scale rows over the length of the body; a wedge-shaped snout, without a keratinized keel; and a broad, pyriform (R. adocetus) or ovate (R. hatmaliyeb) rostral scale.

  12. The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: two new species of Ramphotyphlops from the Caroline Islands

    USGS Publications Warehouse

    Wynn, Addison H.; Reynolds, Robert P.; Buden, Donald W.; Falanruw, Marjorie; Lynch, Brian

    2012-01-01

    Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R. adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excluding Ramphotyphlops braminus). Both species are unusual in being known only from small, low-lying atolls. They can be distinguished from other Ramphotyphlops by the combination of 22 scale rows over the length of the body; a wedge-shaped snout, without a keratinized keel; and a broad, pyriform (R. adocetus) or ovate (R. hatmaliyeb) rostral scale.

  13. ["Lingue di seripi", "serpents' tongues" and "glossopetrae". Highlights from the history of popular "cult" medicine in early modern times].

    PubMed

    Freller, T

    1997-01-01

    In the 16th, 17th and 18th century "Glossopetrae", popularly known as "Lingue di Serpi", found on the Mediterranean island of Malta, were extensively used for medical purposes as antidotes. These fossil teeth, including specimens of the "Carcharodon Megalodon" (an extinct variant of the great white shark), were ground to powder or used as amulet pendants and "credence" and exported to pharmacies and shops in various cities of Europe. In antiquity, authors like Plinius or Solinus, excluding any religious connotations, had regarded "Glossopetrae" as objects "fallen from heaven on dark moonless nights". However, from the beginning of the 16th century the miraculous antidotic power of the specimens found at Malta was very strongly connected with the Pauline cult there. This cult owed ist origin to the excerpt of the shipwreck of the Apostle of the Gentiles on this island, as recorded in the New Testament. As in so many cases found in medieval and early modern medicine and pharmacy, the renown, collection, distribution and use of the antidote "Glossopetrae" or "Lingue di Serpi" was never limited to its real chemical and pharmaceutical properties. In the period of enlightenment and secular thinking mythic medicine as "Glossopetrae" had lost ist "magical" power. Consequently, with beginning of the late 18th century also the Maltese "Glossopetrae" featured in literature merely as exotic objects of curiosity or symbols of an age bound to medical superstition. PMID:9333999

  14. A new species of triadal coral snake of the genus Micrurus Wagler, 1824 (Serpentes: Elapidae) from northeastern Brazil.

    PubMed

    Pires, Matheus Godoy; Da Silva, Nelson Jorge; Feitosa, Darlan Tavares; Prudente, Ana Lúcia Da Costa; Filho, Gentil Alves Pereira; Zaher, Hussam

    2014-01-01

    The genus Micrurus comprises 123 currently recognized taxa (species and subspecies) that are traditionally arranged in four species groups diagnosable mainly by color pattern characteristics. Here, we describe a new species of triadal coral snake from northeastern Brazil. The new species is distinguished from other sympatric triadal congeners (M. lemniscatus carvalhoi, M. ibiboboca and M. brasiliensis) mainly by the entirely black parietals and by a suite of external characters and hemipenial morphology. The new species appears to be restricted to tropical ombrophilous lowland coastal forests of northeastern Brazil and all recently collected specimens are known to occur in small forest patches surrounded by periurban environment, which calls for an urgent evaluation on its conservation status. PMID:24943187

  15. Body size as a primary determinant of ecomorphological diversification and the evolution of mimicry in the lampropeltinine snakes (Serpentes: Colubridae).

    PubMed

    Pyron, R Alexander; Burbrink, F T

    2009-10-01

    Evolutionary correlations between functionally related character suites are expected as a consequence of coadaptation due to physiological relationships between traits. However, significant correlations may also exist between putatively unrelated characters due to shared relationships between those traits and underlying variables, such as body size. Although such patterns are often dismissed as simple body size scaling, this presumption may overlook important evolutionary patterns of diversification. If body size is the primary determinant of potential diversity in multiple unrelated characters, the observed differentiation of species may be governed by variability in body size, and any biotic or abiotic constraints on the diversification thereof. Here, we demonstrate that traits related to both predatory specialization (gape and diet preference) and predatory avoidance (the development of Batesian mimicry) are phylogenetically correlated in the North American snake tribe Lampropeltini. This is apparently due to shared relationships between those traits and adult body size, suggesting that size is the primary determinant of ecomorphological differentiation in the lampropeltinines. Diversification in body size is apparently not linked to climatic or environmental factors, and may have been driven by interspecific interactions such as competition. Additionally, we find the presence of a 'key zone' for the development of both rattle- and coral snake mimicry; only small snakes feeding primarily on ectothermic prey develop mimetic colour patterns, in or near the range of venomous model species. PMID:19702841

  16. Molecular phylogeny and taxonomy of the Epictia goudotii Species complex (Serpentes: Leptotyphlopidae: Epictinae) in Middle America and northern South America.

    PubMed

    McCranie, James R; Hedges, S Blair

    2016-01-01

    Here we review the systematics of the threadsnakes of the Epictia goudotii Species complex in Middle and northern South America using external morphology and molecular data. Two species, Epictia goudotii and E. magnamaculata, are currently recognized from that region, but we provide evidence for recognizing, as species, three other nominal forms usually treated as subspecies of E. goudotii: E. ater, E. bakewelli, and E. phenops. Thus, together with E. columbi (Bahamas), we recognize six species in the Epictia goudotii Species complex. Because E. albifrons from northern South America has been confused with E. goudotii in the past, we also briefly discuss the taxonomic status of that species and its apparent close relative E. tenella, which are not members of the E. goudotii complex. PMID:26788430

  17. Systematics of Nothopsini (Serpentes, Dipsadidae), with a new species of Synophis from the Pacific Andean slopes of southwestern Ecuador

    PubMed Central

    Pyron, R. Alexander; Guayasamin, Juan M.; Peñafiel, Nicolás; Bustamante, Lucas; Arteaga, Alejandro

    2015-01-01

    Abstract Within Dipsadinae, some recent authors have recognized a tribe Nothopsini containing the genera Diaphorolepis, Emmochliophis, Nothopsis, Synophis, and Xenopholis, on the basis of a number of putative morphological synapomorphies. However, molecular results suggest that Nothopsis, Synophis, and Xenopholis do not form a monophyletic group, while the remaining taxa are unsampled in recent molecular phylogenies. Here, DNA-sequence data for some Diaphorolepis and Synophis species are provided for the first time, as well as additional new sequences for Nothopsis and some Synophis species. Including these and other existing data for nothopsine species, previous studies showing that Nothopsini is not a natural group are corroborated. Nothopsini Cope, 1871 is restricted to Nothopsis. Diaphorolepidini Jenner, 1981 is resurrected and re-delimited to include only Diaphorolepis, Emmochliophis, and Synophis. Finally, Xenopholis remains Dipsadinae incertae sedis. Known material of Diaphorolepidini is reviewed to generate revised and expanded descriptions and diagnoses at the tribe, genus, and species level. Numerous cryptic species are likely present in Synophis bicolor and Synophis lasallei. Finally, a new population from the low-elevation cloud forests of SW Ecuador is reported upon, which is genetically and morphologically distinct from all other species, that is here named Synophis zaheri sp. n. PMID:26798284

  18. Genetic differentiation among species of the genus Thermophis Malnate (Serpentes, Colubridae) and comments on T. shangrila.

    PubMed

    Hofmann, Sylvia; Tillack, Frank; Miehe, Georg

    2015-01-01

    The genus Thermophis includes the two species, T. baileyi and T. zhaoermii, which differ morphologically, geographically and molecularly. Recently, a third Thermophis species was described from Shangri-La, northern Yunnan Province, China, and named T. shangrila. The new species was based on morphological and genetic data derived from three specimens. However, the morphological features used to delimit this species seem vague, because they may fall within the range of intraspecific variation of T. zhaoermii. Furthermore, the reported genetic differences in nuclear data are questionable. They likely resulted from a misinterpretation probably due to alignment/analytical flaws or sample/sequence mix-up. Here, we used partial sequences of three mitochondrial (CO1, ND4, cytb) genes and one nuclear (c-mos) gene to analyse the genetic variation between and within species of Thermophis. We inferred the phylogeny using Bayesian Inference and Maximum Likelihood approaches and present additional morphological data that contribute to the knowledge on intraspecific variation in the genus. Our results indicate lacking robustness in the distinguishing morphological features and in the genetic differentiation of T. shangrila and highlight the need for more detailed morphological and molecular studies from a substantially larger sample. PMID:26624298

  19. The complete mitochondrial genome of the striped-tailed rat-snake, Orthriophis taeniurus (Reptilia, Serpentes, Colubridae).

    PubMed

    Li, En; Sun, Fuxiao; Zhang, Ruidong; Chen, Jing; Wu, Xiaobing

    2016-01-01

    The complete mitochondrial genome (mitogenome) of the striped-tailed rat-snake Orthriophis taeniurus was determined in the present study. The genome is 17,183?bp in size, containing 2 ribosomal RNA (rRNA) genes, 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and 2 control regions (CRI and CRII). The gene order and orientation in O. taeniurus mitogenome are basically identical to that of other alethinophidian snakes. Nucleotide composition is very similar with other vertebrates, showing an AT bias. PMID:24730609

  20. A taxonomic revision of the Asian keelback snakes, genus Amphiesma (Serpentes: Colubridae: Natricinae), with description of a new species.

    PubMed

    Guo, Peng; Liu, Qin; Zhang, Liang; Li, Jian X; Huang, Yu Y; Pyron, R Alexander

    2014-01-01

    The Asian keelback snakes (genus Amphiesma) are a widely distributed group of Old World natricines, inhabiting a variety of niches and exhibiting significant morphological variation. Recent molecular phylogenies suggest that this genus is not monophyletic, and that additional cryptic diversity is also likely present. We conducted a phylogenetic analysis of the group based on 3162 bp of one mitochondrial gene (Cyt. b) and three nuclear genes (C-mos, Rag1, NT3), sampling 18 species in addition to those sequenced in previous works. All analyses consistently show that Amphiesma consists of three distinct, monophyletic lineages with strong support. We divide Amphiesma into three genera, Amphiesma, Hebius, and Herpetoreas. The genus Amphiesma is monotypic, Herpetoreas contains three species, and Hebius comprises the remaining 39 species. On the basis of a combination of molecular analyses and external morphological comparisons, we describe a new species in the Herpetoreas group from China as H. burbrinki sp. nov. Several other species are shown to be non-monophyletic or contain significant levels of intraspecific genetic diversity. Another Old World natricine genera, Xenochrophis is also found to be non-monophyletic. Our results indicate that further taxonomic revisions are needed in Natricinae, at multiple levels.  PMID:25544230

  1. No time to worship the serpent deities: women, economic change, and religion in north-western Nepal.

    PubMed

    Saul, R

    1999-03-01

    This paper explores the changing relationships between lay women, and the spiritual realm, in two ethnic Tibetan communities, Kag and Dzong, in northwestern Nepal. The study tackles how economic and social change has affected women's spiritual roles within the household and the community, and how these roles, in turn, have influenced the course of such change. In Kag, the introduction of tourism changed women's way of life. They became income-generating members of the community as lodge-owners. With new responsibilities to manage, Kag women eventually neglected their traditional social and spiritual obligations, much to the dismay of the older generation. On the other hand, women in Dzong still consider full social and physical participation in village life important despite the added obligations. They maintain spiritual harmony within the village. Dzongba women do not seem to feel the same conflicts as Kagpa women. The negative impact of Kag women's neglect of traditional social and spiritual responsibilities should be weighed against the possible benefits to women, household, and economy. PMID:12295339

  2. Molecular phylogeny and taxonomy of the Epictia goudotii Species complex (Serpentes: Leptotyphlopidae: Epictinae) in Middle America and northern South America

    PubMed Central

    McCranie, James R.

    2016-01-01

    Here we review the systematics of the threadsnakes of the Epictia goudotii Species complex in Middle and northern South America using external morphology and molecular data. Two species, Epictia goudotii and E. magnamaculata, are currently recognized from that region, but we provide evidence for recognizing, as species, three other nominal forms usually treated as subspecies of E. goudotii: E. ater, E. bakewelli, and E. phenops. Thus, together with E. columbi (Bahamas), we recognize six species in the Epictia goudotii Species complex. Because E. albifrons from northern South America has been confused with E. goudotii in the past, we also briefly discuss the taxonomic status of that species and its apparent close relative E. tenella, which are not members of the E. goudotii complex. PMID:26788430

  3. The real identity of Leptodira nycthemera Werner, 1901 from Ecuador: a junior synonym of Oxyrhopus petolarius (Linnaeus, 1758) (Serpentes, Dipsadidae)

    PubMed Central

    Costa, João Carlos Lopes; Kucharzewski, Christoph; Prudente, Ana Lúcia da Costa

    2015-01-01

    Abstract Leptodira nycthemera Werner, 1901, was described from a specimen collected in Ecuador. No information on the holotype was published after its description. In the most recent review of Leptodeira, Leptodira nycthemera was considered to be a synonym of Leptodeira annulata annulata, although the author emphasized that the holotype was lost and did not include the pholidotic data from the original description in his account of Leptodeira annulata annulata. Since this review, a number of authors have accepted this synonymy. Recently, analyzing specimens of Leptodeira in the Museum für Naturkunde, Berlin, Germany, we discovered the holotype of Leptodira nycthemera. This holotype is re-described here, and its correct identity is determined. Based on the analysis of meristic characters and the color of the holotype, we recognize Leptodira nycthemera as a junior synonym of Oxyrhopus petolarius. PMID:26085798

  4. Serpent: Magnetic signatures of serpentinized mantle and mesoscale oceanic variability along the Alaska/Aleutian subduction zone

    NASA Astrophysics Data System (ADS)

    Purucker, Michael; Serpent Team

    2010-05-01

    NASA recently solicited suborbital missions as a part of its new Earth Venture program element. These missions are designed as complete PI-led investigations to conduct innovative, integrated, hypothesis or scientific question driven approaches to pressing questions in Earth System science. The missions should require sustained observations (<5 years) and significant resources (<30 million USD). The submitted mission proposals have been under evaluation since last November, and NASA is scheduled to make a decision in April. We, a team led by Raytheon's Photon Research Associates, propose to carry out a suborbital magnetic survey of the Aleutian subduction zone using NASA's Global Hawk to test the magnetic serpentinite hypothesis. This hypothesis states that dewatering of the descending slab within subduction zones produces an observable static magnetic signature through the formation of serpentinite in the overriding mantle. This signature may serve as a predictor of the location of large megathrust earthquakes and their associated tsunamis. Magnetic field measurements from 20 km (sub-orbital) altitude are essential to the testing of this hypothesis; analysis shows orbital and/or near-surface measurements are not likely to provide sufficient sensitivity and uniform calibration to confirm or reject the hypothesis, nor to consistently map its presence around the world. Static and dynamic magnetic signatures from the motion of seawater in the earth's magnetic field have the potential to confound an evaluation of the magnetic serpentinite hypothesis. Through a combination of modeling and exact repeat surveys over the subduction zone, spaced weeks to as much as six months apart, we can study the magnetic signature of the motion that characterizes the mesoscale oceanic circulation in order to develop the best possible corrections for lithospheric imaging, and elucidating the intrinsic and unique oceanic information content in the magnetic fields for the first time ever. The role of water in subduction zones, and in the overlying ocean, can be traced by sustained suborbital observations of the magnetic field. At critical depths of 40 to 50 km, subducting ocean crust goes through important metamorphic changes that release large amounts of water into overriding mantle rocks. Introduction of water into the mantle produces serpentinite, a highly magnetic, low-density rock. Thermal models indicate that, in many of the world's subduction zones, this part of the mantle is cooler than the Curie temperature of magnetite, the most important magnetic mineral in serpentinite, and thus large volumes of mantle in subduction-margin settings should be magnetic. Indeed, analysis of magnetic data from some subduction zones indicates that magnetic mantle can be detected in long-wavelength magnetic anomalies. The presence of serpentinite in subduction margins has two important links to large within-slab and giant megathrust earthquakes, and associated tsunamis. First, release of water from the subducting slab is thought to embrittle the slab, thereby promoting within-slab earthquakes (M 7-8). Thus, we expect to see a spatial association between this type of earthquake and mantle magnetic anomalies. Second, in cool subduction margins, the down-dip limit of megathrust earthquakes (M 8.0-9.6) is controlled by the slab's first encounter with serpentinized mantle. Again, we expect to see a spatial association between these devastating earthquakes and magnetic anomalies. The magnetic serpentinite hypothesis can be tested by comparison to free-air gravity, geologic, topographic, and bathymetric data of comparable resolution. Significant static and dynamic magnetic fields also originate as a consequence of oceanic flow in electrically conducting ocean water above the subduction zone. Although these signals are of much lower amplitude than the magnetic field associated with serpentinite, they can have significant power at short spatial scales, and thus have the potential to confound estimated magnetic source depths that rely on inferences from the

  5. The Eagle, the Jaguar, and the Serpent. Indian Art of the Americas; North America: Alaska, Canada, the United States.

    ERIC Educational Resources Information Center

    Covarrubias, Miguel

    The origins of Native Americans are traced through art forms in this history of American art. The basic time periods for this history are determined and defined as the formative horizon, the classic horizon, and the historical horizon. Art forms used throughout these time periods are described in terms of technique and aesthetics. The arts and…

  6. "Have You, My Little Serpents, a New Skin?" Transforming English Studies and the Scholarship of Teaching and Learning

    ERIC Educational Resources Information Center

    Easton, Lee; Hewson, Kelly

    2012-01-01

    King and Knight (2010) argue that English Studies' instructors must "articulate and develop their tacit assumptions [about English teaching] and create a discipline-grounded idiom for pedagogical research and reflection" (p. 323). We suggest that the scholarship of teaching and learning (SoTL) invites English educators to reflect more…

  7. Three new endemic species of Epictia Gray, 1845 (Serpentes: Leptotyphlopidae) from the dry forest of northwestern Peru.

    PubMed

    Koch, Claudia; Venegas, Pablo J; Böhme, Wolfgang

    2015-01-01

    Three new blind snake species of the genus Epictia are described based on material collected in the Peruvian Regions Amazonas, Cajamarca and La Libertad. All three species are well differentiated from all congeners based on characteristics of their morphology and coloration. They share 10 scale rows around the middle of the tail and possess two supralabials with the anterior one in broad contact with the supraocular. Epictia septemlineata sp. nov. has 16 subcaudal scales, 257 mid-dorsal scale rows, a yellowish-white rostral, and a black terminal spine. Epictia vanwallachi sp. nov. exhibits 16 subcaudals, 188 mid-dorsal scale rows, a grayish-brown rostral, and a yellow terminal spine. Epictia antoniogarciai sp. nov. features 14-18 subcaudals, 195-208 mid-dorsal scale rows, a bright yellow or yellowish-white rostral, and the terminal spine and terminal portion of the tail yellow. All three species were collected in the interandean dry forest valleys of the Marañón River and its tributaries. This region is an area of endemism and warrants further attention from systematic and conservation biologists. PMID:26249433

  8. Species Delimitation in the Continental Forms of the Genus Epicrates (Serpentes, Boidae) Integrating Phylogenetics and Environmental Niche Models

    PubMed Central

    Rivera, Paula C.; Di Cola, Valeria; Martínez, Juan J.; Gardenal, Cristina N.; Chiaraviglio, Margarita

    2011-01-01

    Until recently, the genus Epicrates (Boidae) presented only one continental species, Epicrates cenchria, distributed in Central and South America, but after a taxonomic revision using morphologic characters five species were recognized: E. cenchria, E. crassus, E. maurus, E. assisi, and E. alvarezi. We analyzed two independent data sets, environmental niche models and phylogeny based on molecular information, to explore species delimitation in the continental species of this genus. Our results indicated that the environmental requirements of the species are different; therefore there are not evidences of ecological interchangeability among them. There is a clear correlation between species distributions and the major biogeographic regions of Central and South America. Their overall distribution reveals that allopatry or parapatry is the general pattern. These evidences suggest that habitat isolation prevents or limits gene exchange among them. The phylogenetic reconstruction showed that the continental Epicrates are monophyletic, being E. alvarezi the sister species for the remaining two clades: E. crassus - E. assisi, and E. maurus - E. cenchria. The clade grouping the continental Epicrates is the sister taxon of the genus Eunectes and not of the Caribbean Epicrates clade, indicating that the genus is paraphyletic. There is a non-consistent pattern in niche evolution among continental Epicrates. On the contrary, a high variation and abrupt shifts in environmental variables are shown when ancestral character states were reconstructed on the sequence-based tree. The degree of genetic and ecological divergence among continental Epicrates and the phylogenetic analyses support the elevation to full species of E. cenchria, E. crassus, E. maurus, E. assisi, and E. alvarezi. PMID:21912634

  9. The Eagle, the Jaguar, and the Serpent. Indian Art of the Americas; North America: Alaska, Canada, the United States.

    ERIC Educational Resources Information Center

    Covarrubias, Miguel

    The origins of Native Americans are traced through art forms in this history of American art. The basic time periods for this history are determined and defined as the formative horizon, the classic horizon, and the historical horizon. Art forms used throughout these time periods are described in terms of technique and aesthetics. The arts and…

  10. Systematics of Nothopsini (Serpentes, Dipsadidae), with a new species of Synophis from the Pacific Andean slopes of southwestern Ecuador.

    PubMed

    Pyron, R Alexander; Guayasamin, Juan M; Peñafiel, Nicolás; Bustamante, Lucas; Arteaga, Alejandro

    2015-01-01

    Within Dipsadinae, some recent authors have recognized a tribe Nothopsini containing the genera Diaphorolepis, Emmochliophis, Nothopsis, Synophis, and Xenopholis, on the basis of a number of putative morphological synapomorphies. However, molecular results suggest that Nothopsis, Synophis, and Xenopholis do not form a monophyletic group, while the remaining taxa are unsampled in recent molecular phylogenies. Here, DNA-sequence data for some Diaphorolepis and Synophis species are provided for the first time, as well as additional new sequences for Nothopsis and some Synophis species. Including these and other existing data for nothopsine species, previous studies showing that Nothopsini is not a natural group are corroborated. Nothopsini Cope, 1871 is restricted to Nothopsis. Diaphorolepidini Jenner, 1981 is resurrected and re-delimited to include only Diaphorolepis, Emmochliophis, and Synophis. Finally, Xenopholis remains Dipsadinae incertae sedis. Known material of Diaphorolepidini is reviewed to generate revised and expanded descriptions and diagnoses at the tribe, genus, and species level. Numerous cryptic species are likely present in Synophis bicolor and Synophis lasallei. Finally, a new population from the low-elevation cloud forests of SW Ecuador is reported upon, which is genetically and morphologically distinct from all other species, that is here named Synophis zaheri sp. n. PMID:26798284

  11. Biological and immunological properties of the venom of Bothrops alcatraz, an endemic species of pitviper from Brazil.

    PubMed

    Furtado, M F D

    2005-06-01

    Bothrops alcatraz is a new pitviper species derived from the Bothrops jararaca group, whose natural habitat is situated in Alcatrazes Archipelago, a group of marine islands near São Paulo State coast in Brazil. Herein, the biological and biochemical properties of venoms of four adult specimens of B. alcatraz were examined comparatively to a reference pool of Bothrops jararaca venom. Both venoms showed similar activities and electrophoretic patterns, but B. alcatraz venom showed three protein bands of molecular masses of 97, 80 and 38 kDa that were not present in B. jararaca reference venom. The i.p. median lethal dose of B. alcatraz venom ranged from 5.1 to 6.6 mg/kg, while it was 1.5 mg/kg for B. jararaca venom. The minimum hemorrhagic dose of B. jararaca venom was 0.63, whereas 2.28 mug/mouse for B. alcatraz venom. In contrast, B. alcatraz venom was more potent in regard to procoagulant and proteolytic activities. These differences were supported by western blotting and neutralization tests, employing commercial bothropic antivenom, which showed that hemorrhagic and lethal activities of B. alcatraz venom were less effectively inhibited than B. jararaca venom. Such results evidence that B. alcatraz shows quantitative and qualitative differences in venom composition in comparison with its B. jararaca relatives, which might represent an optimization of venom towards a specialized diet. PMID:16002343

  12. Phylogenetic relationships within Bothrops neuwiedi group (Serpentes, Squamata): geographically highly-structured lineages, evidence of introgressive hybridization and Neogene/Quaternary diversification.

    PubMed

    Machado, Taís; Silva, Vinícius X; Silva, Maria José de J

    2014-02-01

    Eight current species of snakes of the Bothrops neuwiedi group are widespread in South American open biomes from northeastern Brazil to southeastern Argentina. In this paper, 140 samples from 93 different localities were used to investigate species boundaries and to provide a hypothesis of phylogenetic relationships among the members of this group based on 1122bp of cyt b and ND4 from mitochondrial DNA and also investigate the patterns and processes occurring in the evolutionary history of the group. Combined data recovered the B. neuwiedi group as a highly supported monophyletic group in maximum parsimony, maximum likelihood and Bayesian analyses, as well as four major clades (Northeast I, Northeast II, East-West, West-South) highly-structured geographically. Monophyly was recovered only for B. pubescens. By contrast, B. diporus, B. lutzi, B. erythromelas, B. mattogrossensis, B. neuwiedi, B. marmoratus, and B. pauloensis, as currently defined on the basis of morphology, were polyphyletic. Sympatry, phenotypic intergrades and shared mtDNA haplotypes, mainly between B. marmoratus and B. pauloensis suggest recent introgressive hybridization and the possible occurrence of a narrow hybrid zone in Central Brazil. Our data suggest at least three candidate species: B. neuwiedi from Espinhaço Range, B. mattogrossensis (TM173) from Serra da Borda (MT) and B. diporus (PT3404) from Castro Barros, Argentina. Divergence estimates highlight the importance of Neogene events in the origin of B. neuwiedi group, and the origin of species and diversification of populations of the Neotropical fauna from open biomes during the Quaternary climate fluctuations. Data reported here represent a remarkable increase of the B. neuwiedi group sampling size, since representatives of all the current recognized species from a wide geographic range are included in this study, providing basic information for understanding the evolution and conservation of Neotropical biodiversity. PMID:24140980

  13. Geographic genetic structure in two laticaudine sea kraits, Laticauda laticaudata and Laticauda semifasciata (Serpentes: Elapidae), in the Ryukyu-Taiwan region as inferred from mitochondrial cytochrome b sequences.

    PubMed

    Tandavanitj, Nontivich; Ota, Hidetoshi; Cheng, Yuan-Cheng; Toda, Mamoru

    2013-08-01

    The Ryukyu-Taiwan region is an island arch with intervening waters of varying distances and depths. This study examines the geographic genetic structure of two sympatric sea kraits, Laticauda laticaudata and L. semifasciata, in the region, to infer factors affecting the extent of dispersal and other biogeographical traits of these amphibious reptiles. Sequence analyses of the mitochondrial cytochrome b gene revealed four and 16 haplotypes for L. laticaudata (136 individuals) and L. semifasciata (177 individuals), respectively. For both species, population pairwise F ST analyses revealed significant genetic differentiations among islands and island groups, which are separated by deep straits, suggesting that deep waters serve as obstacles for dispersal in both species. Significant genetic differentiation was detected even among islands of the same basin in L. laticaudata, but not in L. semifasciata, and the isolation by distance analyses revealed no significant correlation between geographic and genetic distances in the former species. These results further suggest that L. laticaudata has stronger site fidelity or degree of philopatry than L. semifasciata. Based on the geographic genetic patterns, the historical biogeography of the two species in the Ryukyu-Taiwan region is also discussed. PMID:23915156

  14. Genetic divergence and diversity in the Mona and Virgin Islands Boas, Chilabothrus monensis (Epicrates monensis) (Serpentes: Boidae), West Indian snakes of special conservation concern.

    PubMed

    Rodríguez-Robles, Javier A; Jezkova, Tereza; Fujita, Matthew K; Tolson, Peter J; García, Miguel A

    2015-07-01

    Habitat fragmentation reduces the extent and connectivity of suitable habitats, and can lead to changes in population genetic structure. Limited gene flow among isolated demes can result in increased genetic divergence among populations, and decreased genetic diversity within demes. We assessed patterns of genetic variation in the Caribbean boa Chilabothrus monensis (Epicrates monensis) using two mitochondrial and seven nuclear markers, and relying on the largest number of specimens of these snakes examined to date. Two disjunct subspecies of C. monensis are recognized: the threatened C. m. monensis, endemic to Mona Island, and the rare and endangered C. m. granti, which occurs on various islands of the Puerto Rican Bank. Mitochondrial and nuclear markers revealed unambiguous genetic differences between the taxa, and coalescent species delimitation methods indicated that these snakes likely are different evolutionary lineages, which we recognize at the species level, C. monensis and C. granti. All examined loci in C. monensis (sensu stricto) are monomorphic, which may indicate a recent bottleneck event. Each population of C. granti exclusively contains private mtDNA haplotypes, but five of the seven nuclear genes assayed are monomorphic, and nucleotide diversity is low in the two remaining markers. The faster pace of evolution of mtDNA possibly reflects the present-day isolation of populations of C. granti, whereas the slower substitution rate of nuDNA may instead mirror the relatively recent episodes of connectivity among the populations facilitated by the lower sea level during the Pleistocene. The small degree of overall genetic variation in C. granti suggests that demes of this snake could be managed as a single unit, a practice that would significantly increase their effective population size. PMID:25837733

  15. Redescription of Haemogregarina garnhami (Apicomplexa: Adeleorina) from the blood of Psammophis schokari (Serpentes: Colubridae) as Hepatozoon garnhami n. comb. based on molecular, morphometric and morphologic characters.

    PubMed

    Abdel-Baki, Abdel-Azeem S; Al-Quraishy, Saleh; Zhang, J Y

    2014-06-01

    Hepatozoon garnhami n. comb. was redescribed from Schokari sand snakes (Psammophis schokari) collected from Riyadh city in Saudi Arabia. Gametocytes were found in the peripheral blood of 2 of 15 snakes examined. Based on the similar morphological and morphometric characteristics, the same host and a similar host habitat environment, it can be concluded for the first time that the present species is conspecific with Haemogregarina garnhami previously reported from Psammophis shokari aegyptius. To further characterize this parasite, the partial 18S rRNA gene was amplified and sequenced. The sequence analysis also showed that Haemogregarina garnhami should be reassigned into the genus Hepatozoon as Hepatozoon garnhami which has 99.5% (859/863 bp) sequence similarity to Hepatozoon ayorgbor, infecting the erythrocytes of Python regius in Ghana. Phylogenetic analysis showed that H. garnhami formed a mixed clade with Hepatozoon spp. from geckos, snakes and rodents and ophidian Hepatozoon spp. did not form a separated phylogenetic unit. Also, Psammophis schokari-infecting Hepatozoon contained several different genetic lineages. To our knowledge, the present work extends the geographic distribution of H. garnhami and is the first report of Hepatozoon infection in snakes from Saudi Arabia. PMID:24827101

  16. Effectiveness of phylogenomic data and coalescent species-tree methods for resolving difficult nodes in the phylogeny of advanced snakes (Serpentes: Caenophidia).

    PubMed

    Pyron, R Alexander; Hendry, Catriona R; Chou, Vincent M; Lemmon, Emily M; Lemmon, Alan R; Burbrink, Frank T

    2014-12-01

    Next-generation genomic sequencing promises to quickly and cheaply resolve remaining contentious nodes in the Tree of Life, and facilitates species-tree estimation while taking into account stochastic genealogical discordance among loci. Recent methods for estimating species trees bypass full likelihood-based estimates of the multi-species coalescent, and approximate the true species-tree using simpler summary metrics. These methods converge on the true species-tree with sufficient genomic sampling, even in the anomaly zone. However, no studies have yet evaluated their efficacy on a large-scale phylogenomic dataset, and compared them to previous concatenation strategies. Here, we generate such a dataset for Caenophidian snakes, a group with >2500 species that contains several rapid radiations that were poorly resolved with fewer loci. We generate sequence data for 333 single-copy nuclear loci with ?100% coverage (?0% missing data) for 31 major lineages. We estimate phylogenies using neighbor joining, maximum parsimony, maximum likelihood, and three summary species-tree approaches (NJst, STAR, and MP-EST). All methods yield similar resolution and support for most nodes. However, not all methods support monophyly of Caenophidia, with Acrochordidae placed as the sister taxon to Pythonidae in some analyses. Thus, phylogenomic species-tree estimation may occasionally disagree with well-supported relationships from concatenated analyses of small numbers of nuclear or mitochondrial genes, a consideration for future studies. In contrast for at least two diverse, rapid radiations (Lamprophiidae and Colubridae), phylogenomic data and species-tree inference do little to improve resolution and support. Thus, certain nodes may lack strong signal, and larger datasets and more sophisticated analyses may still fail to resolve them. PMID:25193610

  17. "So it really does exist-the sea-Serpent we've never believed in!" Ferenczi's influence on Freud revisited.

    PubMed

    Bonomi, Carlo

    2013-12-01

    In the last phase of his work, Ferenczi created a new language for trauma, based on the fragmentation of mental life. In the paper on "The principles of relaxation and neocatharsis," Ferenczi reformulated the goal of analysis by proposing that "no analysis can be regarded … as complete unless we have succeed in penetrating the traumatic material", where the "traumatic material" was not to be sought in the neurotic reactions and adaptive solutions of the ego but in more primitive reactions, such as the psychotic turning away from reality, splitting, and fragmentation. This was exactly the material that Freud assimilated in the essay "A disturbance of memory on the Acropolis", after the death of Ferenczi. Freud visited Athens in 1904, and the walk up to the Parthenon represented the successful coronation of his self-analysis. Actually, the hallucination turned out to be so uncanny that he never again visited Athens. In a letter to Fliess, written shortly before the meeting in Nuremberg, on January 24, 1897, Freud reported on a case history turning on a "scene about the circumcision of a girl," who later was convincingly identified by Schur as Emma Eckstein. Did Freud have the germinal idea that Emma Eckstein's hallucination of the penis contained the wish to overcome her trauma and the hope to have a restored genital? Is this the holy visitation, which haunted him on the Acropolis? Why did he give up the profound insight that the dreams of gigantic snakes had a traumatic origin? PMID:24309686

  18. Feeding ecology of Erythrolamprus jaegeri jaegeri (Günter, 1858) and Erythrolamprus poecilogyrus sublineatus (Cope, 1860) in the coastal zone of Subtropical Brazil (Serpentes, Dipsadidae).

    PubMed

    Corrêa, Daniele N; Quintela, Fernando M; Loebmann, Daniel

    2016-03-01

    The snakes Erythrolamprus jaegeri jaegeri and Erythrolamprus poecilogyrus sublineatus are sympatric and syntopic in the coastal region of southern Brazil. Herein, we analyzed the diet composition to evaluate the niche breadth and the prey selection by both species. We examined 192 specimens, and analysis of stomach contents revealed that both species predominantly consume anurans. However, the diet of E. j. jaegeri consists mainly of fish and amphibians, whereas that of E. p. sublineatus is broader, including fish, amphibians, reptiles and mammals. The Standardized Levins Index presented lower values for E. j. jaegeri (BA = 0.17) than for E. p. sublineatus (BA = 0.61), evidencing specialist and generalist strategies for each species, respectively. Regarding prey selection, E. p. sublineatus presented a larger snout-vent length, head, mouth and lower jaw than E. j. jaegeri and fed on larger prey. In addition, positive correlations between the size and weight of predators and prey were confirmed in both species. The results show the development of different mechanisms for co-occurrence of the two species, such as prey selection by size, such that the size of the predator is related to the size of their prey, or by developing different strategies to decrease niche overlap between species. PMID:26840002

  19. Optimization of geometry, material and economic parameters of a two-zone subcritical reactor for transmutation of nuclear waste with SERPENT Monte Carlo code

    NASA Astrophysics Data System (ADS)

    Gulik, Volodymyr; Tkaczyk, Alan Henry

    2014-06-01

    An optimization study of a subcritical two-zone homogeneous reactor was carried out, taking into consideration geometry, material, and economic parameters. The advantage of a two-zone subcritical system over a single-zone system is demonstrated. The study investigated the optimal volume ratio for the inner and outer zones of the subcritical reactor, in terms of the neutron-physical parameters as well as fuel cost. Optimal geometrical parameters of the system are suggested for different material compositions.

  20. 77 FR 4810 - Pesticide Products; Receipt of Applications To Register New Uses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-31

    ..., great-headed, garlic, lily bulb, pearl onion, potato onion, serpent garlic, shallot, green onion..., fritillaria bulb, great-headed, garlic, lily bulb, pearl onion, potato onion, serpent garlic, shallot, green..., potato, tomato, acerola, atemoya, biriba, cherimoya, custard apple, dragon fruit, feijoa, guava,...

  1. The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes.

    NASA Astrophysics Data System (ADS)

    Balam Matagamon, Chan; Pawa Matagamon, Sagamo

    2004-03-01

    Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light, or by the elicitation of pin-like prickings, by somewhat intense nervous-system response, by EMF interactions with aural electrochemical systems that can elicit tinitus, and other ways. In the northeast, Cautantowit served as a harbinger of Indian summer, and appears to be another alter ego of the EMF. The Miami, FL Tequesta site along the river clearly correlates with tornado, earthquake and hurricane locations. Sites like the Mohave Deserts giant man may have had similar significance.

  2. 77 FR 30524 - Pesticide Products; Receipt of Applications To Register New Uses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ..., Mediterranean mandarin, Mount White lime, New Guinea wild lime, Russell River lime, sweet lime, tachibana orange...-headed, serpent), lily (bulb), onion (bulbs of common, Chinese, pearl, potato), shallot (bulb)...

  3. RICIS Software Engineering 90 Symposium: Aerospace Applications and Research Directions Proceedings

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Papers presented at RICIS Software Engineering Symposium are compiled. The following subject areas are covered: synthesis - integrating product and process; Serpent - a user interface management system; prototyping distributed simulation networks; and software reuse.

  4. Haematopoiesis in snakes (Ophidia) in early postnatal development.

    PubMed

    Dabrowski, Z; Sano Martins, I S; Tabarowski, Z; Witkowska-Pelc, E; Spadacci Morena, D D; Spodaryk, K; Podkowa, D

    2007-05-01

    The occurrence of haematopoiesis has been studied in various parts of the spine and in the ribs in four species of snakes (Boa constrictor L., Elaphe guttata L., Lamprophis fulaginosus Boie., Bothrops jararaca Wied.) from hatching until 150 days of postnatal development. Marrow spaces are formed by chondrolysis with various time frames depending on the studied species. Marrow cells egress to the general circulation in two ways: via migration through the endothelial cells lining the venous sinuses or by the rupture of protrusions. Erythroblasts are present in the lumen of marrow sinuses suggesting their final maturation there. Various relationships of the spleen to the pancreas have been found. No myelopoietic foci occur in the spleen, liver or kidney of any of the studied species. However, erythropoiesis (sparse islets) has been observed in Bothrops jararaca spleen. PMID:17225172

  5. [Studies on hemorrhagic toxins from the venoms of Trimeresurus mucrosquamatus, Crotalus ruber ruber, Vipera aspis aspis and Agkistrodon acutus and arginine ester hydrolases from Trimeresurus mucrosquamatus venom].

    PubMed

    Nikai, T; Komori, Y; Sugihara, H

    2000-04-01

    Venom samples were corrected from several poisonous snakes, such as Bungarus multicinctus, Trimeresurus mucrosquamatus, T. gramineus, T. flavoviridis, and Agkistrodon acutus, and stored in a desiccator at room temperature for 25 to 31 years. Then they were compared with fresh venoms as to their biological activities. The characteristic local symptoms produced by the bite of venomous snakes of Crotalidae and Viperidae are hemorrhage, necrosis and muscular degeneration. Hemorrhagic toxins were purified from Trimeresurus mucrosquamatus, Crotalus ruber ruber, Vipera aspis aspis, and Agkistrodon acutus venoms and their biological, biochemical, and pathological properties were investigated. Arginine ester hydrolases are present in the venoms of Crotalidae and Viperidae, but are not found in the venoms of Elapidae and Hydrophiidae. In this paper we describe the enzymatic and biological activities of arginine ester hydrolases from a Trimeresurus mucrosquamatus venom. PMID:10774254

  6. Comment on Spracklandus Hoser, 2009 (Reptilia, Serpentes, ELAPIDAE): request for confirmation of availability of the generic name and for the nomenclatural validation of the journal in which it was published (Case 3601; BZN 70:234–237; 71:30–38; 133-135,181-182 ,252-253)

    USGS Publications Warehouse

    Rhodin, Anders G.J.; Kaiser, Hinrich; van Dijk, Peter Paul; Wüster, Wolfgang; O’Shea, Mark; Archer, Michael; Auliya, Mark; Boitani, Luigi; Bour, Roger; Clausnitzer, Viola; Contreras-MacBeath, Topiltzin; Crother, Brian I.; Daza, Juan M.; Driscoll, Carlos A.; Flores-Villela, Oscar; Frazier, Jack; Fritz, Uwe; Gardner, Alfred L.; Gascon, Claude; Georges, Arthur; Glaw, Frank; Grazziotin, Felipe G.; Groves, Colin P.; Haszprunar, Gerhard; Havaš, Peter; Hero, Jean-Marc; Hoffmann, Michael; Hoogmoed, Marinus S.; Horne, Brian D.; Iverson, John B.; Jäch, Manfred; Jenkins, Christopher L.; Jenkins, Richard K.B.; Kiester, A. Ross; Keogh, J. Scott; Lacher, Thomas E., Jr.; Lovich, Jeffrey E.; Luiselli, Luca; Mahler, D. Luke; Mallon, David P.; Mast, Roderic; McDiarmid, Roy W.; Measey, John; Mittermeier, Russell A.; Molur, Sanjay; Mosbrugger, Volker; Murphy, Robert W.; Naish, Darren; Niekisch, Manfred; Ota, Hidetoshi; Parham, James F.; Parr, Michael J.; Pilcher, Nicolas J.; Pine, Ronald H.; Rylands, Anthony B.; Sanderson, James G.; Savage, Jay M.; Schleip, Wulf; Scrocchi, Gustavo J.; Shaffer, H. Bradley; Smith, Eric N.; Sprackland, Robert; Stuart, Simon N.; Vetter, Holger; Vitt, Laurie J.; Waller, Tomás; Webb, Grahame; Wilson, Edward O.; Zaher, Hussam; Thomson, Scott

    2015-01-01

    In Case 3601 Raymond Hoser has asked the Commission to validate for the purposes of nomenclature the name Spracklandus Hoser, 2009, and ‘the journal in which it was published,’ issue 7 of the Australasian Journal of Herpetology (AJH). We note that the entire run of AJH has been written, edited, and published solely by Hoser. Although his requests to the Commission were presented as narrow and, in his words, ‘routine matters,’ we are convinced that they represent an important tipping-point with broad implications of major concern for zoological taxonomy and nomenclature as a whole and, by extension, the greater scientific community. Since Hoser’s actions and works have failed to follow scientific best practices (e.g. Turtle Taxonomy Working Group, 2007, 2014; Kaiser et al., 2013; Kaiser, 2014) and both the Commission’s general Recommendations and Code of Ethics in Appendix A, the global herpetological community has widely rejected his taxonomic decisions and resultant nomenclature. This has unfortunately caused a confusing dual nomenclature to develop in the herpetological community, with most boycotting or ignoring Hoser’s 700+ new names coined in the AJH, while he and a few personal followers actively promote their usage. We believe that suppression of the name Spracklandus, and all issues of AJH, is the only effective way to bring this contentious and confusing issue to resolution. The plenary power available under Article 81.1 of the Code exist specifically to allow the Commission to make rulings in individual cases that disturb stability and cause confusion, whether the works are Code-compliant or not. We maintain that it is in the interest of nomenclatural stability, not only for herpetology, but for all of zoological taxonomy, that the plenary power be invoked to declare the works in AJH unavailable, regardless of any narrow interpretation of their technical Code-compliance. We present our arguments for rejection of the validity of AJH in the following commentary. In view of the wide-reaching implications of this case for all of zoology, and reflecting the deep and broad-based community concern over these issues, our contributing authors include 70 global scientific leaders and accomplished amateurs from a wide variety of zoological disciplines.

  7. The Chinese representation of cosmic elements as graphic symbols.

    PubMed

    Mahdihassan, S

    1988-01-01

    In Chinese cosmology, cosmic elements have been deified and assigned life-forms. Air, representing ultrasonic energy as a celestial entity, became bird-god, Red-bird. Water acquired Dragon as its representative and Fire had Tiger as its graphic symbol. Earth, as body, was fertile and long-lasting. It was symbolized as Tortoise, known to be long-lived. Its soul became Serpent, long enough to be powerful as Cosmic soul. Serpent-Tortoise, as Body-Soul, became the god Black-Warrior in charge of Earth. PMID:3218627

  8. Asclepius, Caduceus, and Simurgh as medical symbols, part I.

    PubMed

    Nayernouri, Touraj

    2010-01-01

    This is the first of two articles reviewing the history of medical symbols. In this first article I have briefly reviewed the evolution of the Greek god, Asclepius, (and his Roman counterpart Aesculapius) with the single serpent entwined around a wooden rod as a symbol of western medicine and have alluded to the misplaced adoption of the Caduceus of the Greek god Hermes (and his Roman counterpart Mercury) with its double entwined serpents as an alternative symbol. In the second part of this article (to be published later), I have made a tentative suggestion of why the Simorgh might be adopted as an Eastern or an Asian symbol for medicine. PMID:20039773

  9. Animal Symbols in the Art of the Hodensaunee.

    ERIC Educational Resources Information Center

    Hill, Richard

    1987-01-01

    Explains the significance of the main animal symbols incorporated into the social, cultural, artistic, and spiritual fabric of the Hodenosaunee (the People of the Longhouse) also known as the Six Nations Iroquois: the eagle, turtle, bear, wolf, hawk, heron, snipe, eel, deer, beaver, moose, snake, and serpent. (NEC)

  10. Software engineering activities at SEI (Software Engineering Institute)

    NASA Technical Reports Server (NTRS)

    Chittister, Clyde

    1990-01-01

    Prototyping was shown to ease system specification and implementation, especially in the area of user interfaces. Other prototyping approaches do not allow for the evolution of the prototype into a production system or support maintenance after the system is fielded. A set of goals is presented for a modern user interface environment and Serpent, a prototype implementation that achieves these goals, is described.

  11. The history of the evil eye and its influence on ophthalmology, medicine and social customs.

    PubMed

    Bohigian, G H

    1997-01-01

    Belief in the evil eye is one of the oldest and most widespread superstitions in the world. The concept of the evil eye has influenced present day ophthalmology, medicine, and social customs. Oculus sinister (OS), the serpent and the staff of Asclepius, the symbol of RX, and many social customs are historically related to the evil eye. PMID:9657293

  12. Determination of sphingomyelinase-D activity of Loxosceles venoms in sphingomyelin/cholesterol liposomes containing horseradish peroxidase.

    PubMed

    Gomes, Marco Túlio R; Guimarães, Gabriela; Frézard, Frédéric; Kalapothakis, Evanguedes; Minozzo, João Carlos; Chaim, Olga Meiri; Veiga, Silvio Sanches; Oliveira, Sergio Costa; Chávez-Olórtegui, Carlos

    2011-03-15

    Based on degradation of sphingomyelin/cholesterol liposomes containing entrapped horseradish peroxidase, we evaluated the Sphingomyelinase-D (SMase-D) activity of scorpion, spider and snake venoms by monitoring spectrophotometrically the product of oxidation of HRP released. The results indicate that Loxosceles crude venoms (Loxosceles intermedia, Loxosceles laeta, Loxosceles gaucho and Loxosceles similis) displayed SMase-D activity in a concentration-dependent manner. Furthermore, this activity was blocked by the anti-loxoscelic antivenom. However, Tityus serrulatus scorpion venom, Phoneutria nigriventer spider venom and Bothrops jararaca, Crotalus durissus, Lachesis muta and Micrurus frontalis snake venoms did not show measurable SMase-D activity. PMID:21236288

  13. Inhibition of Hemorragic Snake Venom Components: Old and New Approaches

    PubMed Central

    Panfoli, Isabella; Calzia, Daniela; Ravera, Silvia; Morelli, Alessandro

    2010-01-01

    Snake venoms are complex toxin mixtures. Viperidae and Crotalidae venoms, which are hemotoxic, are responsible for most of the envenomations around the world. Administration of antivenins aimed at the neutralization of toxins in humans is prone to potential risks. Neutralization of snake venom toxins has been achieved through different approaches: plant extracts have been utilized in etnomedicine. Direct electric current from low voltage showed neutralizing properties against venom phospholipase A2 and metalloproteases. This mini-review summarizes new achievements in venom key component inhibition. A deeper knowledge of alternative ways to inhibit venom toxins may provide supplemental treatments to serum therapy. PMID:22069593

  14. [Rod of Asclepius. Symbol of medicine].

    PubMed

    Young, Pablo; Finn, Bárbara C; Bruetman, Julio E; Cesaro Gelos, Jorge; Trimarchi, Hernán

    2013-09-01

    Symbolism is one of the most archaic forms of human thoughts. Symbol derives from the Latin word symbolum, and the latter from the Greek symbolon or symballo, which means "I coincide, I make matches". The Medicine symbol represents a whole series of historical and ethical values. Asclepius Rod with one serpent entwined, has traditionally been the symbol of scientific medicine. In a misconception that has lasted 500 years, the Caduceus of Hermes, entwined by two serpents and with two wings, has been considered the symbol of Medicine. However, the Caduceus is the current symbol of Commerce. Asclepius Rod and the Caduceus of Hermes represent two professions, Medicine and Commerce that, in ethical practice, should not be mixed. Physicians should be aware of their real emblem, its historical origin and meaning. PMID:24522424

  15. Ophiuchus

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    (the Serpent-bearer; abbrev. Oph, gen. Ophiuchi; area 948 sq. deg.) An equatorial constellation which lies between Hercules and Scorpius, and culminates at midnight in mid-June. The ecliptic cuts across the southern part of Ophiuchus, but the constellation is not included among the constellations of the zodiac. Ophiuchus is usually said to represent Asclepius, the Greek god of medicine, and is sh...

  16. Five in situ observations of live oarfish Regalecus glesne (Regalecidae) by remotely operated vehicles in the oceanic waters of the northern Gulf of Mexico.

    PubMed

    Benfield, M C; Cook, S; Sharuga, S; Valentine, M M

    2013-07-01

    As part of the SERPENT Project, five observations of apparently healthy oarfish Regalecus glesne by remotely operated vehicles are reported from the northern Gulf of Mexico. Regalecus glesne were observed between 2008 and 2011 at depths from within the epipelagic and mesopelagic zones. These observations include the deepest verified record of R. glesne (463-492?m) and the first record of an arthropod ectoparasite (isopod). PMID:23808690

  17. Extremely low nerve growth facior (NGF) activity of sea snake (Hydrophiidae) venoms.

    PubMed

    Mariam, Khafizova; Tu, Anthony T

    2002-12-01

    Sea snake venoms contain less protein than those of land snakes (Toom et al., 1969). Sea snake venoms lack arginine ester hydrolyzing activity, whereas those of Crotalidae and Viperidae have such activity (Tu et al., 1966). Sea snakes live in salty water, and their venoms may be different from those of land snakes. Because of the difficulty in obtaining sea snake venoms, information about sea snake venoms is quite incomplete. NGF is commonly present in the venoms of land snakes such as Elapidae, Viperidae, and Crotalidae (Cohen and Levi-Montalcini, 1956; Lipps, 2002). It is therefore of interest to investigate the presence or absence of NGF in sea snake venoms. In order to investigate the presence or absence of NGF, five sea snake venoms were selected. Lapemis hardwickii (Hardwick's sea snake) and Acalyptophis peronii venom were obtained from the Gulf of Thailand. Hydrophis cyanocinctus (common sea snake) and Enhydrina schistosa (beaked sea snake) venom were obtained from the Strait of Malacca. Laticauda semifasciata (broad band blue sea snake) venom was also examined and the venom was obtained from Gato Island in the Philippines. PMID:12503884

  18. Snakebites in Hungary--epidemiological and clinical aspects over the past 36 years.

    PubMed

    Malina, Tamás; Krecsák, László; Korsós, Zoltán; Takács, Zoltán

    2008-05-01

    Epidemiological and clinical aspects of snakebites in Hungary between 1970 and 2006 were surveyed. A total of 97 cases were recorded from 21 species, including the two native vipers, Vipera berus and Vipera ursinii, and various exotic species represented by Viperidae, Elapidae, and Colubridae. Bites by native species on laymen are uncommon (17 cases) and present trivial clinical manifestations. Compared with the consequences of native Vipera cases, bites by exotic species often resulted in severe or life-threatening envenomations. These cases were treated with antivenom administration, plasmapheresis, fasciotomy, and amputation. There were two fatalities caused by V. berus and Agkistrodon contortrix. Both of these cases were inflicted in snake-handlers with a previous history of Viperidae bites and the cause of deaths are attributed to anaphylactic reactions as a consequence of hypersensitivity to the venom. Snake-handlers and their physicians face a major challenge due to the diversity and severity of signs and symptoms following exotic venomous snakebites, and the risk of anaphylaxis or anaphylactoid reactions in patients with repeated exposure to snake venom and antivenom. Highly dangerous venomous snake species continue to appear in collections of Hungarian snake-handlers. PMID:18241904

  19. Computation of a Canadian SCWR unit cell with deterministic and Monte Carlo codes

    SciTech Connect

    Harrisson, G.; Marleau, G.

    2012-07-01

    The Canadian SCWR has the potential to achieve the goals that the generation IV nuclear reactors must meet. As part of the optimization process for this design concept, lattice cell calculations are routinely performed using deterministic codes. In this study, the first step (self-shielding treatment) of the computation scheme developed with the deterministic code DRAGON for the Canadian SCWR has been validated. Some options available in the module responsible for the resonance self-shielding calculation in DRAGON 3.06 and different microscopic cross section libraries based on the ENDF/B-VII.0 evaluated nuclear data file have been tested and compared to a reference calculation performed with the Monte Carlo code SERPENT under the same conditions. Compared to SERPENT, DRAGON underestimates the infinite multiplication factor in all cases. In general, the original Stammler model with the Livolant-Jeanpierre approximations are the most appropriate self-shielding options to use in this case of study. In addition, the 89 groups WIMS-AECL library for slight enriched uranium and the 172 groups WLUP library for a mixture of plutonium and thorium give the most consistent results with those of SERPENT. (authors)

  20. Hematopoiesis in snakes (Ophidia).

    PubMed

    Dabrowski, Z; Tabarowski, Z; Sano-Martins, I S; Spadacci-Morena, D D; Witkowska-Pelc, E; Krzysztofowicz, E; Spodaryk, K

    2002-01-01

    Locations of the hematopoietic tissue have been described in the following ophidian species: Bothrops jararaca, Bothrops jararacusu, Waglerophis merremii, Elaphe teniura teniura, Boa constrictor, and Python reticulatus. Studies were carried out on perfusion fixed vertebrae, ribs, spleen, liver, thymus, and kidney. Routine histological technique was applied using both light and electron microscopy. Hematopoietic tissue was found in the following locations of the vertebrae: neural spine, neural arch, postzygophysis processes, hypapophysis, vertebral centre. Moreover, intense hematopoiesis was found inside the ribs. In the spleen and thymus, only lymphopoiesis was found. Hematopoietic islets in the spleen were sporadically found only in young specimens. No hematopoiesis was observed in the liver and kidney. In the studied species, there were no differences in the location of hematopoietic tissue. A new model of mature and immature blood cell release to the lumen of marrow sinuses different from that known to operate in higher vertebrates is proposed. PMID:12056654

  1. PAS-FTIR and FT-Raman qualitative characterization of sodium dodecyl sulfate interaction with an alternative stratum corneum model membrane.

    PubMed

    Baby, A R; Lacerda, A C L; Kawano, Y; Velasco, M V R; Kaneko, T M

    2007-10-01

    The interaction of the surfactant sodium dodecyl sulfate with the stratum corneum (SC) of shed snake skin from Bothrops jararaca, used as a model membrane, was characterized qualitatively by FT-Raman and infrared photoacoustic (PAS-FTIR) spectroscopy, used as analytical tools. Surfactant solutions were 50.0 g x l(-1) and 2.34 g x l(-1) with treatment intervals of 4, 8 and 12 h. The employment of FT-Raman and PAS-FTIR indicated increased hydration of the SC with alteration of the tissue topography. The interaction of the SC with surfactant was increased by the tape-stripping process. The consequent exposure of the internal layers of the tissue intensified the effect of the anionic surfactant, indicating that this layer acted as an additional barrier. PMID:18236773

  2. A SPREADING FACTOR IN CERTAIN SNAKE VENOMS AND ITS RELATION TO THEIR MODE OF ACTION.

    PubMed

    Duran-Reynals, F

    1939-01-01

    The venom of several species of poisonous snakes acts to spread India ink through the skin as do the spreading factors procurable from certain tissues and elaborated by invasive bacteria. The factor is most abundant in the venom of the Viperidae (rattlesnake) family and relatively scant in the venom of Colubridae proteroglypha (cobra) family, and it is absent from toad venom. Extracts of the supralabial glands of harmless snakes contain only negligible amounts of the factor. Rattlesnake venom heated at 65 degrees to 100 degrees loses a large proportion of its toxicity but retains the ability to spread ink. Rattlesnake venom that has lost its toxicity on standing or on heating markedly enhances the infection produced by bacterial or virus suspension in the rabbit skin. Antivenine serum inactivates both the toxic and spreading factors of venom. PMID:19870838

  3. Biochemical characterization, action on macrophages, and superoxide anion production of four basic phospholipases A2 from Panamanian Bothrops asper snake venom.

    PubMed

    Rueda, Aristides Quintero; Rodríguez, Isela González; Arantes, Eliane C; Setúbal, Sulamita S; Calderon, Leonardo de A; Zuliani, Juliana P; Stábeli, Rodrigo G; Soares, Andreimar M

    2013-01-01

    Bothrops asper (Squamata: Viperidae) is the most important venomous snake in Central America, being responsible for the majority of snakebite accidents. Four basic PLA2s (pMTX-I to -IV) were purified from crude venom by a single-step chromatography using a CM-Sepharose ion-exchange column (1.5 × 15?cm). Analysis of the N-terminal sequence demonstrated that pMTX-I and III belong to the catalytically active Asp49 phospholipase A2 subclass, whereas pMTX-II and IV belong to the enzymatically inactive Lys49 PLA2s-like subclass. The PLA2s isolated from Panama Bothrops asper venom (pMTX-I, II, III, and IV) are able to induce myotoxic activity, inflammatory reaction mainly leukocyte migration to the muscle, and induce J774A.1 macrophages activation to start phagocytic activity and superoxide production. PMID:23509779

  4. Current challenges for confronting the public health problem of snakebite envenoming in Central America.

    PubMed

    Gutiérrez, José María

    2014-01-01

    Snakebite envenoming is a serious public health problem in Central America, where approximately 5,500 cases occur every year. Panama has the highest incidence and El Salvador the lowest. The majority, and most severe, cases are inflicted by the pit viper Bothrops asper (family Viperidae), locally known as 'terciopelo', 'barba amarilla' or 'equis'. About 1% of the bites are caused by coral snakes of the genus Micrurus (family Elapidae). Despite significant and successful efforts in Central America regarding snakebite envenomings in the areas of research, antivenom manufacture and quality control, training of health professionals in the diagnosis and clinical management of bites, and prevention of snakebites, much remains to be done in order to further reduce the impact of this medical condition. This essay presents seven challenges for improving the confrontation of snakebite envenoming in Central America. Overcoming these challenges demands a coordinated partnership of highly diverse stakeholders though inter-sectorial and inter-programmatic interventions. PMID:24602234

  5. Biochemical Characterization, Action on Macrophages, and Superoxide Anion Production of Four Basic Phospholipases A2 from Panamanian Bothrops asper Snake Venom

    PubMed Central

    Rueda, Aristides Quintero; Rodríguez, Isela González; Arantes, Eliane C.; Setúbal, Sulamita S.; Calderon, Leonardo de A.; Zuliani, Juliana P.; Stábeli, Rodrigo G.; Soares, Andreimar M.

    2013-01-01

    Bothrops asper (Squamata: Viperidae) is the most important venomous snake in Central America, being responsible for the majority of snakebite accidents. Four basic PLA2s (pMTX-I to -IV) were purified from crude venom by a single-step chromatography using a CM-Sepharose ion-exchange column (1.5 × 15?cm). Analysis of the N-terminal sequence demonstrated that pMTX-I and III belong to the catalytically active Asp49 phospholipase A2 subclass, whereas pMTX-II and IV belong to the enzymatically inactive Lys49 PLA2s-like subclass. The PLA2s isolated from Panama Bothrops asper venom (pMTX-I, II, III, and IV) are able to induce myotoxic activity, inflammatory reaction mainly leukocyte migration to the muscle, and induce J774A.1 macrophages activation to start phagocytic activity and superoxide production. PMID:23509779

  6. Inhibition of Lung Tumor Colonization and Cell Migration with the Disintegrin Crotatroxin 2 Isolated from the Venom of Crotalus atrox

    PubMed Central

    Galán, Jacob A.; Sánchez, Elda E.; Rodríguez-Acosta, Alexis; Soto, Julio G.; Bashir, Sajid; McLane, Mary Ann; Paquette-Straub, Carrie; Pérez, John C.

    2009-01-01

    Disintegrins are low molecular weight proteins (4-15 kDa) with an RGD binding region at their binding loop. Disintegrin and disintegrin-like proteins are found in the venom of four families of snakes: Atractaspididae, Elapidae, Viperidae and Colubridae. This report describes the biological activity of a disintegrin, crotatroxin 2, isolated by a three-step chromatography procedure from the venom of the Western diamondback rattlesnake (Crotalus atrox). The intact molecular mass for crotatroxin 2 was 7.384 kDa and 71 amino acids. Crotatroxin 2 inhibited human whole blood platelet aggregation with an IC50 of 17.5 nM, inhibited cell (66.3p) migration by 63%, and inhibited experimental lung tumor colonization in BALB/c mice at 1000 ?g/kg. Our data suggest that while crotatroxin 2 inhibits platelet aggregation, cancer cell migration, and lung tumor colonization it is done via different integrins. PMID:18387648

  7. Wide distribution of cysteine-rich secretory proteins in snake venoms: isolation and cloning of novel snake venom cysteine-rich secretory proteins.

    PubMed

    Yamazaki, Yasuo; Hyodo, Fumiko; Morita, Takashi

    2003-04-01

    Cysteine-rich secretory proteins (CRISPs) are found in epididymis and granules of mammals, and they are thought to function in sperm maturation and in the immune system. Recently, we isolated and obtained clones for novel snake venom proteins that are classified as CRISP family proteins. To elucidate the distribution of snake venom CRISP family proteins, we evaluated a wide range of venoms for immuno-cross-reactivity. Then we isolated, characterized, and cloned genes for three novel CRISP family proteins (piscivorin, ophanin, and catrin) from the venom of eastern cottonmouth (Agkistrodon piscivorus piscivorus), king cobra (Ophiophagus hannah), and western diamondback rattlesnake (Crotalus atrox). Our results show the wide distribution of snake venom CRISP family proteins among Viperidae and Elapidae from different continents, indicating that CRISP family proteins compose a new group of snake venom proteins. PMID:12646276

  8. Bionic research of pit vipers on infrared imaging.

    PubMed

    Zhang, Zhigang; Zhang, Yong; Zhang, Qingchuan; Cheng, Teng; Wu, Xiaoping

    2015-07-27

    The members of viperidae crotalinae (pit viper) family have special pit organs to detect infrared radiation in normal room conditions, whereas most artificial uncooled infrared focal plane arrays (FPAs) operate only in a vacuum chamber. Dissection shows that the pit membrane is a unique substrate-free structure. The temperature rise advantage of this pit organ was verified in comparison with an assumed substrate pit organ (as an artificial FPA structure). Inspired by the pit viper, we introduced this structure to infrared FPA, replacing the conventional substrate FPA. The substrate-free FPA was fabricated by micro-elctromechanical systems (MEMS) process and placed into an infrared imaging system to obtain thermal images of the human body in atmosphere and vacuum working conditions. We show that the infrared capability of the substrate-free pit organ was achieved. PMID:26367591

  9. Antitumoral Potential of Tunisian Snake Venoms Secreted Phospholipases A2

    PubMed Central

    Zouari-Kessentini, Raoudha; Srairi-Abid, Najet; Bazaa, Amine; El Ayeb, Mohamed; Luis, Jose; Marrakchi, Naziha

    2013-01-01

    Phospholipases type A2 (PLA2s) are the most abundant proteins found in Viperidae snake venom. They are quite fascinating from both a biological and structural point of view. Despite similarity in their structures and common catalytic properties, they exhibit a wide spectrum of pharmacological activities. Besides being hydrolases, secreted phospholipases A2 (sPLA2) are an important group of toxins, whose action at the molecular level is still a matter of debate. These proteins can display toxic effects by different mechanisms. In addition to neurotoxicity, myotoxicity, hemolytic activity, antibacterial, anticoagulant, and antiplatelet effects, some venom PLA2s show antitumor and antiangiogenic activities by mechanisms independent of their enzymatic activity. This paper aims to discuss original finding against anti-tumor and anti-angiogenic activities of sPLA2 isolated from Tunisian vipers: Cerastes cerastes and Macrovipera lebetina, representing new tools to target specific integrins, mainly, α5β1 and αv integrins. PMID:23509718

  10. Fast analysis of low molecular mass compounds present in snake venom: identification of ten new pyroglutamate-containing peptides.

    PubMed

    Wermelinger, Luciana Serrão; Dutra, Denis L S; Oliveira-Carvalho, Ana L; Soares, Márcia Regina; Bloch, Carlos; Zingali, Russolina B

    2005-01-01

    Characterization of the peptide content in snake venoms can be an important tool for the investigation of new pharmacological lead compounds. For this purpose, single-step analysis of crude venoms has recently been demonstrated using mass spectrometry (MS) techniques. Reproducible profiles of ions in MS and MS/MS spectra may also be used to compare venoms from different species. In this work matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) was used to obtain mass patterns of the major peptides (<8 kDa) found in pooled venoms from the genera Bothrops and Crotalus. Venoms from five different Bothrops species (B. jararaca, B. insularis, B. alternatus, B. jararacussu, and B. neuwiedi) and three Crotalus species (C. viridis, C. adamanteus and C. durissus terrificus) were analyzed. In agreement with other reports, venoms from Bothrops species contained a variety of peptides in the range m/z 1000-1500, and in some samples larger components (m/z 7000-8000) were detected. In the Crotalus species venoms were rich in peptides ranging from m/z 1000-1500 and 4000-5500. MS/MS experiments on the low molecular mass peptides (m/z 1000-1500) confirmed the presence of ten new bradykinin-potentiating peptides among venoms from genera Bothrops and Crotalus. In order to determine whether additional peptides could be identified after partial purification, B. jararaca venom was subjected to size-exclusion chromatography on Sephacryl S-200, and two distinct low molecular mass pools were analyzed further by MALDI-TOFMS. No additional peptides were detected from the pool with masses below 2000 Da but a substantial improvement with better resolution was observed for the pool with masses above 7000 Da, indicating that complex samples such as crude snake venoms can be analyzed for low molecular mass peptides using a single-step procedure. PMID:15912471

  11. Comparative Sex Chromosome Genomics in Snakes: Differentiation, Evolutionary Strata, and Lack of Global Dosage Compensation

    PubMed Central

    Zektser, Yulia; Mahajan, Shivani; Bachtrog, Doris

    2013-01-01

    Snakes exhibit genetic sex determination, with female heterogametic sex chromosomes (ZZ males, ZW females). Extensive cytogenetic work has suggested that the level of sex chromosome heteromorphism varies among species, with Boidae having entirely homomorphic sex chromosomes, Viperidae having completely heteromorphic sex chromosomes, and Colubridae showing partial differentiation. Here, we take a genomic approach to compare sex chromosome differentiation in these three snake families. We identify homomorphic sex chromosomes in boas (Boidae), but completely heteromorphic sex chromosomes in both garter snakes (Colubridae) and pygmy rattlesnake (Viperidae). Detection of W-linked gametologs enables us to establish the presence of evolutionary strata on garter and pygmy rattlesnake sex chromosomes where recombination was abolished at different time points. Sequence analysis shows that all strata are shared between pygmy rattlesnake and garter snake, i.e., recombination was abolished between the sex chromosomes before the two lineages diverged. The sex-biased transmission of the Z and its hemizygosity in females can impact patterns of molecular evolution, and we show that rates of evolution for Z-linked genes are increased relative to their pseudoautosomal homologs, both at synonymous and amino acid sites (even after controlling for mutational biases). This demonstrates that mutation rates are male-biased in snakes (male-driven evolution), but also supports faster-Z evolution due to differential selective effects on the Z. Finally, we perform a transcriptome analysis in boa and pygmy rattlesnake to establish baseline levels of sex-biased expression in homomorphic sex chromosomes, and show that heteromorphic ZW chromosomes in rattlesnakes lack chromosome-wide dosage compensation. Our study provides the first full scale overview of the evolution of snake sex chromosomes at the genomic level, thus greatly expanding our knowledge of reptilian and vertebrate sex chromosomes evolution. PMID:24015111

  12. Effect of taxon sampling on recovering the phylogeny of squamate reptiles based on complete mitochondrial genome and nuclear gene sequence data.

    PubMed

    Albert, Eva M; San Mauro, Diego; García-París, Mario; Rüber, Lukas; Zardoya, Rafael

    2009-07-15

    The complete nucleotide sequences of the mitochondrial (mt) genomes of three species of squamate lizards: Blanus cinereus (Amphisbaenidae), Anguis fragilis (Anguidae), and Tarentola mauritanica (Geckkonidae) were determined anew. The deduced amino acid sequences of all 13 mt protein-coding genes were combined into a single data set and phylogenetic relationships among main squamate lineages were analyzed under maximum likelihood (ML) and Bayesian Inference (BI). Within Squamata, the monophyly of Iguanidae, Anguimorpha, Amphisbaenia, Gekkota, Serpentes, and Acrodonta received high statistical support with both methods. It is particularly striking that this is the first molecular analysis that recovers the monophyly of Scincomorpha (including Scincidae, Xantusiidae, Cordylidae, and Lacertidae), although it is only supported in the Bayesian analysis, and it is sensitive to changes in the outgroup (see below). Phylogenetic relationships among the main squamate lineages could not be resolved with ML but received strong support with BI (above 95%). The newly reconstructed phylogeny of squamates does not support the Iguania-Scleroglossa split. Acrodonta and Serpentes form a clade, which is the sister group of the remaining squamate lineages. Within these, Gekkota were the first branching out, followed by Amphisbaenia, and a clade including Anguimorpha as sister group of Scincomorpha + Iguanidae. The recovered topology differed substantially from previously reported hypotheses on squamate relationships, and the relative effect of using different outgroups, genes, and taxon samplings were explored. The sister group relationship of Serpentes + Acrodonta, and their relative basal position within Squamata could be due to a long-branch attraction artifact. Phylogenetic relationships among Scincomorpha, Amphisbaenia, and Anguimorpha were found to be rather unresolved. Future improving of squamate phylogenetic relationships would rely on finding snake and acrodont species with slower mt evolutionary rates, ensuring thorough taxon coverage of squamate diversity, and incorporating more nuclear genes with appropriate evolutionary rates. PMID:18639394

  13. Time Correlations in Fluid Transport Obtained by Sequential Rephasing Gradient Pulses

    NASA Astrophysics Data System (ADS)

    Stapf, Siegfried; Damion, Robin A.; Packer, Ken J.

    1999-04-01

    We present a basic experiment by which the evolution of the displacement probability density (propagator) of static or flowing fluid inNsuccessive time intervals is obtained by single labeling, coupled with multiple rephasing events during the course of a pulsed field-gradient sequence. We term this type of sequence SERPENT: SEquential Rephasing by Pulsed field-gradients Encoding N Time-intervals. Realizations of the SERPENT experiment for the caseN= 2 which include spin echo, stimulated echo, and Carr-Purcell pulse sequences are suggested. They have in common a spatial spin-labeling of the initial magnetization by a gradient of area q0, followed by successive rephasing via gradients q1and q2at timest= ?1andt= ?2, respectively, where q0+ q1+ q2= 0. A two-dimensional Fourier transform with respect to q1and q2gives directly the joint probability densityW2(R1, ?1; R2, ?2) for displacements R1and R2in times ?1and ?2, respectively. q1and q2may be in arbitrary directions. Assuming R1?R2, the correlation coefficient ?R1,R2then reflects the time-history of the fluctuating velocities. The behavior of the cross moment can be obtained from either a full two-dimensional or a set of one-dimensional SERPENT measurements. Experimental results are presented for water flowing through a bed of packed glass beads. While ?1is appropriately chosen to sample the short-time velocity field within the system, increasing ?2clearly shows the loss of correlation when the average fluid element displacement exceeds the bead diameter.

  14. Preliminary Analysis of the Transient Reactor Test Facility (TREAT) with PROTEUS

    SciTech Connect

    Connaway, H. M.; Lee, C. H.

    2015-11-30

    The neutron transport code PROTEUS has been used to perform preliminary simulations of the Transient Reactor Test Facility (TREAT). TREAT is an experimental reactor designed for the testing of nuclear fuels and other materials under transient conditions. It operated from 1959 to 1994, when it was placed on non-operational standby. The restart of TREAT to support the U.S. Department of Energy’s resumption of transient testing is currently underway. Both single assembly and assembly-homogenized full core models have been evaluated. Simulations were performed using a historic set of WIMS-ANL-generated cross-sections as well as a new set of Serpent-generated cross-sections. To support this work, further analyses were also performed using additional codes in order to investigate particular aspects of TREAT modeling. DIF3D and the Monte-Carlo codes MCNP and Serpent were utilized in these studies. MCNP and Serpent were used to evaluate the effect of geometry homogenization on the simulation results and to support code-to-code comparisons. New meshes for the PROTEUS simulations were created using the CUBIT toolkit, with additional meshes generated via conversion of selected DIF3D models to support code-to-code verifications. All current analyses have focused on code-to-code verifications, with additional verification and validation studies planned. The analysis of TREAT with PROTEUS-SN is an ongoing project. This report documents the studies that have been performed thus far, and highlights key challenges to address in future work.

  15. Astronomy at Teotihuacan

    NASA Astrophysics Data System (ADS)

    Iwaniszewski, Stanisław

    Located 37 km from Mexico City, during the first part of the first millennium AD, Teotihuacan was one of the world's largest and most populated cities. The city controlled the obsidian mines and developed far-reaching economic and political interactions, especially with the Classic Maya dynasties, Monte Albán in the Valley of Oaxaca and the Mexican Gulf Coast. Teotihuacan-made pottery and jewelry along with talud-tablero architectural style and the cult of the Feathered Serpent and Rain gods was spread throughout Mesoamerica.

  16. Geobotanical techniques for discriminating serpentine rock types in Western United States

    NASA Technical Reports Server (NTRS)

    Mouat, D.; Elvidge, C.; Lyon, R.

    1982-01-01

    The effectiveness of airborne multispectral imagery for identifying vegetation indicative of serpentine soils, which usually contain deposits of Ni, Cr, and Co, was examined with ground truth data. Analyses were carried out in SW Oregon, the Jasper Ridge of the Santa Cruz Mountains, and the Sierra Nevada foothills. Airborne studies were performed with 10-channel scanner, a IR scanner, and with false color composites, while ground studies classified the vegetation and mineral contents of the soil. The airborne studies were successfully used to discern serpentine soils from nonultramafic rock types, although difficulties were encountered in separating serpentine from nonserpentinized peridotite. A lack of deciduous trees on serpentized land was noted.

  17. Spectroscopy of Moses Rock Kimberlite Diatreme

    NASA Technical Reports Server (NTRS)

    Pieters, C. M.; Mustard, J. F.

    1985-01-01

    Three types of remote sensing data (Airborne Imaging Spectroscopy (AIS), NS001, Zeiss IR-photographs) were obtained for the Moses Rock kimberlite dike in southern Utah. The goal is to identify and characterize the mantle derived mafic component in such volcanic features. The Zeiss and NS001 images provide information on the regional setting and allow units of the dike to be distinguished from surrounding material. A potential unmapped satellite dike was identified. The AIS data provide characterizing information of the surface composition of the dike. Serpentized olivine-bearing soils are (tentatively) identified from the AIS spectra for a few areas within the dike.

  18. Spatial and spectral effects in subcritical system pulsed experiments

    SciTech Connect

    Dulla, S.; Nervo, M.; Ravetto, P.; Carta, M.

    2013-07-01

    Accurate neutronic models are needed for the interpretation of pulsed experiments in subcritical systems. In this work, the extent of spatial and spectral effects in the pulse propagation phenomena is investigated and the analysis is applied to the GUINEVERE experiment. The multigroup cross section data is generated by the Monte Carlo SERPENT code and the neutronic evolution following the source pulse is simulated by a kinetic diffusion code. The results presented show that important spatial and spectral aspects need to be properly accounted for and that a detailed energy approach may be needed to adequately capture the physical features of the system to the pulse injection. (authors)

  19. Improved Neutronics Treatment of Burnable Poisons for the Prismatic HTR

    SciTech Connect

    Y. Wang; A. A. Bingham; J. Ortensi; C. J. Permann

    2012-10-01

    In prismatic block High Temperature Reactors (HTR), highly absorbing material such a burnable poison (BP) cause local flux depressions and large gradients in the flux across the blocks which can be a challenge to capture accurately with traditional homogenization methods. The purpose of this paper is to quantify the error associated with spatial homogenization, spectral condensation and discretization and to highlight what is needed for improved neutronics treatments of burnable poisons for the prismatic HTR. A new triangular based mesh is designed to separate the BP regions from the fuel assembly. A set of packages including Serpent (Monte Carlo), Xuthos (1storder Sn), Pronghorn (diffusion), INSTANT (Pn) and RattleSnake (2ndorder Sn) is used for this study. The results from the deterministic calculations show that the cross sections generated directly in Serpent are not sufficient to accurately reproduce the reference Monte Carlo solution in all cases. The BP treatment produces good results, but this is mainly due to error cancellation. However, the Super Cell (SC) approach yields cross sections that are consistent with cross sections prepared on an “exact” full core calculation. In addition, very good agreement exists between the various deterministic transport and diffusion codes in both eigenvalue and power distributions. Future research will focus on improving the cross sections and quantifying the error cancellation.

  20. Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles.

    PubMed

    Singarete, Marina E; Grizante, Mariana B; Milograna, Sarah R; Nery, Mariana F; Kin, Koryu; Wagner, Günter P; Kohlsdorf, Tiana

    2015-01-01

    Developmental processes and their results, morphological characters, are inherited through transmission of genes regulating development. While there is ample evidence that cis-regulatory elements tend to be modular, with sequence segments dedicated to different roles, the situation for proteins is less clear, being particularly complex for transcription factors with multiple functions. Some motifs mediating protein-protein interactions may be exclusive to particular developmental roles, but it is also possible that motifs are mostly shared among different processes. Here we focus on HoxA13, a protein essential for limb development. We asked whether the HoxA13 amino acid sequence evolved similarly in three limbless clades: Gymnophiona, Amphisbaenia and Serpentes. We explored variation in ? (dN/dS) using a maximum-likelihood framework and HoxA13sequences from 47 species. Comparisons of evolutionary models provided low ? global values and no evidence that HoxA13 experienced relaxed selection in limbless clades. Branch-site models failed to detect evidence for positive selection acting on any site along branches of Amphisbaena and Gymnophiona, while three sites were identified in Serpentes. Examination of alignments did not reveal consistent sequence differences between limbed and limbless species. We conclude that HoxA13 has no modules exclusive to limb development, which may be explained by its involvement in multiple developmental processes. PMID:26500429

  1. Ophidascaris wangi sp. n. and O. najae (Gedoelst, 1916) (Ascaridida: Ascaridoidea) from snakes in China.

    PubMed

    Li, Liang; Guo, Yan-Ning; Li, Jian; Zhang, Lu-Ping

    2014-12-01

    Ophidascaris wangi sp. n. collected from the king rat snake Elaphe carinata (Günther) (Serpentes: Colubridae) in China is described using both light and scanning electron microscopy. The new species differs from its congeners in the presence of narrow lateral alae originating a short distance posterior to the base of the ventrolateral lips, its relatively long oesophagus (3.57-4.54 mm long, representing 6.6-7.6% of body length), its short spicules (1.89-2.14 mm long, representing 3.9-4.3% of body length), the number and arrangement of caudal papillae (49-57 pairs in total, arranged as follows: 43-51 pairs precloacal, 2 pairs joined paracloacal and 4 pairs postcloacal), the presence of a particular papilliform medioventral, postcloacal ornamentation and the morphology of the eggs and tip of the female tail. In addition, Ophidascaris najae (Gedoelst, 1916), collected from the king cobra Ophiophagus hannah Cantor (Serpentes: Elapidae) in China, is also redescribed. The morphology of the cervical papillae, labial denticles and phasmids of the female is described for the first time. PMID:25651700

  2. Is Continuing Contumely Relative to Mc Leod's Vision and ``Secret Sacred Science, (SSS),'': Contagiously Counterproductive in Science, or an Unhealthy Artifact of ``Turf Wars''?

    NASA Astrophysics Data System (ADS)

    Leod, Roger

    2007-04-01

    Mc Leod confirmed, with physics, his models for vision, and for electromagnetic artifacts, by traditional methods, associated with phenomena like tornados, hurricanes, and earthquakes. The latter confirmations are evidently apparent across current ethnology, cultures, linguistics, religion, rituals, exotic astronomy, somewhat concealed evidence of native record-keeping/writing, and iconography. Use of cultural anthropology while observing a modern Peruvian sacred-site-sweeping at Cuzco, coupled with their assertion that Ñari Huallac means ``serpent God,'' plus electromagnet information, reveals that their religious world-view include(s)(d) applied science that is still otherwise unacknowledged. Alexander Thom's precise megalithic site-measurements also imply that ``The Ancients' Serpent'' made/makes precise tracks that convey valuable information. The linguistics of words like Seminole, and unusual visual effects, reveal some traditionalists have done better than most scientists, for vision, and observational physics, and earth science. Tornado and hurricane tracks are predictable, as are some earthquakes. Tornado ``detuning'' or shutdown is electromagnetically possible. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.7

  3. Mars Hand Lens Imager (MAHLI) Efforts and Observations at the Rocknest Eolian Sand Shadow in Curiosity's Gale Crater Field Site

    NASA Technical Reports Server (NTRS)

    Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Goetz, W.; Kah, L. C.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Beegle, L. W.; Carsten, J. L.; Cooper, B.; Deen, R. G.; Dromart, G.; Eigenbrode, J. L.; Grotzinger, J. P.; Gupta, S.; Hamilton, V. E.; Hardgrove, C. J.; Harker, D. E.; Herkenhoff, K. E.; Herrera, P. N.; Hurowitz, J. A.; Jandura, L.; Ming, D. W.

    2013-01-01

    The Mars Science Laboratory (MSL) mission is focused on assessing the past or present habitability of Mars, through interrogation of environment and environmental records at the Curiosity rover field site in Gale crater. The MSL team has two methods available to collect, process and deliver samples to onboard analytical laboratories, the Chemistry and Mineralogy instrument (CheMin) and the Sample Analysis at Mars (SAM) instrument suite. One approach obtains samples by drilling into a rock, the other uses a scoop to collect loose regolith fines. Scooping was planned to be first method performed on Mars because materials could be readily scooped multiple times and used to remove any remaining, minute terrestrial contaminants from the sample processing system, the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA). Because of this cleaning effort, the ideal first material to be scooped would consist of fine to very fine sand, like the interior of the Serpent Dune studied by the Mars Exploration Rover (MER) Spirit team in 2004 [1]. The MSL team selected a linear eolian deposit in the lee of a group of cobbles they named Rocknest (Fig. 1) as likely to be similar to Serpent Dune. Following the definitions in Chapter 13 of Bagnold [2], the deposit is termed a sand shadow. The scooping campaign occurred over approximately 6 weeks in October and November 2012. To support these activities, the Mars Hand Lens Imager (MAHLI) acquired images for engineering support/assessment and scientific inquiry.

  4. Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles

    PubMed Central

    Singarete, Marina E.; Grizante, Mariana B.; Milograna, Sarah R.; Nery, Mariana F.; Kin, Koryu; Wagner, Günter P.; Kohlsdorf, Tiana

    2015-01-01

    Developmental processes and their results, morphological characters, are inherited through transmission of genes regulating development. While there is ample evidence that cis-regulatory elements tend to be modular, with sequence segments dedicated to different roles, the situation for proteins is less clear, being particularly complex for transcription factors with multiple functions. Some motifs mediating protein-protein interactions may be exclusive to particular developmental roles, but it is also possible that motifs are mostly shared among different processes. Here we focus on HoxA13, a protein essential for limb development. We asked whether the HoxA13 amino acid sequence evolved similarly in three limbless clades: Gymnophiona, Amphisbaenia and Serpentes. We explored variation in ω (dN/dS) using a maximum-likelihood framework and HoxA13sequences from 47 species. Comparisons of evolutionary models provided low ω global values and no evidence that HoxA13 experienced relaxed selection in limbless clades. Branch-site models failed to detect evidence for positive selection acting on any site along branches of Amphisbaena and Gymnophiona, while three sites were identified in Serpentes. Examination of alignments did not reveal consistent sequence differences between limbed and limbless species. We conclude that HoxA13 has no modules exclusive to limb development, which may be explained by its involvement in multiple developmental processes. PMID:26500429

  5. Chromatin supraorganization, DNA fragmentation, and cell death in snake erythrocytes.

    PubMed

    Miyamoto, Maristela; Vidal, Benedicto C; Mello, Maria Luiza S

    2005-02-01

    In nucleate erythrocytes of several vertebrate groups, the frequency and intensity of DNA fragmentation associated with programmed cell death vary considerably. Although hemoglobin efficiency may be related to erythrocyte life span, and hemoglobin types and erythrocyte life spans are assumed to vary in reptiles, no data on DNA fragmentation and chromatin organization as related to cell death exist for snakes. In the present study, chromatin supraorganization, DNA fragmentation, and cell death were investigated in four snake species (Crotalus durissus terrificus, Bothrops jararaca, Bothrops alternatus, and Bothrops neuwiedii), which differ in their geographical distribution and habitats, by using image analysis of Feulgen hydrolysis kinetics, the TUNEL assay, single-cell gel electrophoresis, and transmission electron microscopy. Relatively few circulating erythrocytes were found to be simultaneously committed to cell death, although there was some variation among the snake species. Conspicuous nuclear and cytoplasmic organelles suggestive of metabolic activity were seen ultrastructurally in most snake erythrocytes. The DNA of the snake erythrocyte chromatin was much more resistant to Feulgen acid hydrolysis (DNA depurination and breakdown) than that of young adult bullfrog erythrocytes, which had a high frequency and intensity of DNA fragmentation. Of the species studied, B. neuwiedii and C. d. terrificus showed the greatest resistance to Feulgen acid hydrolysis and to the DNA fragmentation, revealed by the TUNEL assay. Although B. neuwiedii also showed the lowest frequency of cells with more damaged DNA in the single-cell gel electrophoresis assay, C. d. terrificus had the highest frequency of damaged cells, possibly because of the abundance of alkaline-sensitive DNA sites. The results for DNA fragmentation and cell death in erythrocytes of B. jararaca and B. alternatus generally differed from those for C. d. terrificus and B. neuwiedii and may reflect differences in the biology of these species selected under different geographical habitats. The differences in erythrocyte cell biology reported here may be related to hemoglobin variants selected in the mentioned snake species and that would lead the cells to different resistances to unfavorable environmental conditions. PMID:15746963

  6. Spectroscopy of Moses Rock dike using remote sensing

    NASA Technical Reports Server (NTRS)

    Mustard, J. F.; Pieters, C. M.

    1985-01-01

    Zeiss IR-photographs, NS0001 (TM simulator) and airborne imaging spectrometer (AIS) data were obtained for the Moses Rock kimberlite dike in southern Utah to identify and characterize the distinctive mafic mineralogy of the dike as well as the surrounding sedimentary rocks. The Zeiss and NS001 images provide information on the regional setting and allow units of the dike to be distinguished from the sediments. The AIS data are narrow images obtained in 128 near-infrared channels and provide characterizing information on the surface composition through. Three distinct spectroscopic units were found which have been tentatively identified as serpentized olivine-bearing soils found in the dike and two types of gypsum bearing soils found in the surrounding sedimentary soils.

  7. Cyanoacrylate repair of laser in situ keratomileusis corneal flap perforation by a snake bite.

    PubMed

    Korn, Bobby S; Korn, Tommy S

    2005-11-01

    A 30-year-old man who had laser in situ keratomileusis (LASIK) for myopia 1 year earlier developed a corneal perforation in the left eye from a boa constrictor. The patient presented to the emergency room, and a small corneal perforation just outside the visual axis was diagnosed within the LASIK flap. Cyanoacrylate adhesive was used to close the corneal perforation. The patient went on to full visual recovery with an uncorrected visual acuity of 20/20. This is the first reported case of a penetrating corneal injury from a serpent in an eye that had LASIK. Cyanoacrylate may be used to repair small traumatic corneal perforations with a favorable visual outcome in eyes that have had LASIK. PMID:16412943

  8. On the Asclepian spirit and the future of psychoanalysis.

    PubMed

    Whitehead, Clay C

    2002-01-01

    The dynamics of the Asclepian myth are analyzed, and generic dynamics of the healing imperative are illustrated. The story teaches much about the early theories and practice of ancient medicine, and originated the healing symbol of the staff and serpent which appears on the emblem of the American Academy. The multi-modal therapeutic approach used at the Asclepia was often climaxed by dream incubation as a centerpiece of the treatment. Dreams from modern physicians in analysis will be introduced to show that while our practice has changed in external trappings, the underlying dynamics of ancient and modern healers reflect a common humanity. Modern therapists have reacquired the use of dreams and invented a new set of explanatory myths. Consideration of future developments leads to linking the "psychosomatic model" of antiquity with the psychopharmacological interventions which are now common-place in psychodynamic psychotherapy. The Asclepian emphasis on spirituality is also finding increasing recognition among psychoanalysts and other scientists. PMID:12064034

  9. Alteration of Al-rich inclusions inside amoeboid olivine aggregates in the Allende meteorite

    NASA Technical Reports Server (NTRS)

    Hashimoto, Akihiko; Grossman, Lawrence

    1987-01-01

    The primary phases of Al-rich inclusions in amoeboid olivine aggregates have undergone alteration reactions with the solar nebular gas. The simplest interpretation of the present observations is that melilite was the first primary phase to disappear with falling temperature, and was replaced by grossular + anorthite + feldspathoids, followed by fassaite; spinel was the last phase to be altered. Thermodynamic calculations suggest that Na-rich phlogopite could have formed at about 470 K and chlorite at about 328 K at a water fugacity of 0.000001, which is that of a gas of solar composition in this temperature range. The olivine around Al-rich inclusions is not serpentized, indicating the cessation of gas-solid equilibrium above 274 K.

  10. Fine-scale Magnetic Structures and Flows in Sunspot Simulations

    NASA Astrophysics Data System (ADS)

    Kitiashvili, I. N.; Kosovichev, A. G.; Wray, A. A.; Mansour, N. N.

    2012-08-01

    One of most intriguing processes on the Sun is the formation and dynamics of sunspots and active regions, where magneto-convective conditions are very different from quiet Sun regions. High-resolution observations from Hinode and numerical simulations shed light into these processes. In our 3D radiative MHD simulations we take into account real-gas equation of state, ionization and excitation of all abundant spices, turbulent and magnetic effects. We present recent results of numerical simulations of a top layer of the convective zone and the photosphere in the presence of magnetic field of various strength and inclination. The simulation results explain the filamentary organization of penumbra, reveal the mechanisms of the Evershed effect and the sea-serpent behavior of magnetic field lines, and show the subsurface dynamics of umbral dots as a natural consequence of magnetoconvection processes.

  11. e-MERLIN data reduction pipeline

    NASA Astrophysics Data System (ADS)

    Argo, Megan

    2014-07-01

    Written in Python and utilizing ParselTongue (ascl:1208.020) to interface with AIPS (ascl:9911.003), the e-MERLIN data reduction pipeline processes, calibrates and images data from the UK's radio interferometric array (Multi-Element Remote-Linked Interferometer Network). Driven by a plain text input file, the pipeline is modular and can be run in stages. The software includes options to load raw data, average in time and/or frequency, flag known sources of interference, flag more comprehensively with SERPent (ascl:1312.001), carry out some or all of the calibration procedures (including self-calibration), and image in either normal or wide-field mode. It also optionally produces a number of useful diagnostic plots at various stages so data quality can be assessed.

  12. NMR-based diffusion lattice imaging

    NASA Astrophysics Data System (ADS)

    Laun, Frederik Bernd; Müller, Lars; Kuder, Tristan Anselm

    2016-03-01

    Nuclear magnetic resonance (NMR) diffusion experiments are widely employed as they yield information about structures hindering the diffusion process, e.g., about cell membranes. While it has been shown in recent articles that these experiments can be used to determine the shape of closed pores averaged over a volume of interest, it is still an open question how much information can be gained in open well-connected systems. In this theoretical work, it is shown that the full structure information of connected periodic systems is accessible. To this end, the so-called "SEquential Rephasing by Pulsed field-gradient Encoding N Time intervals" (SERPENT) sequence is used, which employs several diffusion encoding gradient pulses with different amplitudes. Two two-dimensional solid matrices that are surrounded by an NMR-visible medium are considered: a hexagonal lattice of cylinders and a rectangular lattice of isosceles triangles.

  13. Infectious disease serologic survey in free-ranging Venezuelan anacondas (Eunectes murinus).

    PubMed

    Calle, P P; Rivas, J; Muñoz, M; Thorbjarnarson, J; Holmstrom, W; Karesh, W B

    2001-09-01

    Reptiles can harbor pathogenic microorganisms asymptomatically and serve as potential reservoirs of infection for humans, domestic animals, and other reptiles. Infectious diseases are also problematic for free-ranging reptile populations and are an important consideration in reptile reintroduction and translocation projects. There have been limited serologic studies of free-ranging reptiles for evidence of exposure to potential pathogens. In the present study, serum or plasma samples from five male and five female free-ranging Venezuelan anacondas (Eunectes murinus) were screened for antibodies to eastern, western, and Venezuelan equine encephalitis viruses, vesicular stomatitis virus, ophidian paramyxovirus, 19 Leptospira interrogans serovars, and Cryptosporidium serpentes. Antibodies to these agents were not detected, or antibody titers were low and possibly nonspecific. These results for the limited number of anacondas surveyed suggest that they do not serve as significant reservoirs for these infectious agents at this location. PMID:12785679

  14. Environmental Aspects of Sites Like America's Stonehenge, (AS), Florida's Miami Tequesta Site, and Lowell's A.D. 1069

    NASA Astrophysics Data System (ADS)

    Ochs, Michael Ann; Mc Leod, Roger D.

    2002-04-01

    Subtle ``instrumentation" is often unnoticed. Stone-chamber transponder-receivers are principle and secondary wave detectors, part of the ``technologic" arsenal of men like Passaconaway/Metacomen of colonial-era Massachusetts, or the earthquake-predicting Shawnee Tecumseh of the Ohio Valley region, during 1811-1813. An Ohio stone-effigy ``serpent" is a thunderstorm precursor signal indicator. The Hopi require similar ``equipment," when duping gullible ``rain-dance" patrons. Tornado/waterspout activity is documented right in the Tequesta site at the river in Miami, Florida, which generates detectable signals. Columbus could have used similar ``secret sacred science" previously learned from American Indians, and thereby successfully predicted an anomalous hurricane on a subsequent trip. These, and the Hawaiian volcano goddess Pelee, seem to be a mythic equivalent of electromagnetically generated signals, i.e., a metaphor for ``environmental applied physics" we detect at A.S.

  15. We Detect Blue Light Phenomena Correlating with Environmental and Weather Changes, and Historic Native Americans or Their Place Names.

    NASA Astrophysics Data System (ADS)

    Ochs, Michael Ann; Mc Leod, Roger D.; Mc Leod, Edward M.

    2003-10-01

    Katahdin (Christ Cathar Spirit-signal stronghold) in Maine is sacred to the Penobscot Indian Nation. That mountain complex, and areas like Ellis Pond, ME and Penley Hill/Anasagunticook (adherent of Jesus Christ Spirit-signal doctor church) of the Mexico/Rumford/Mountain Valley region, also in Maine, have an association with historic Native Americans like the medicine woman Molocket/Molly Ockett. We have observed that these and other regions generate electromagnetic field (EMF) signals, which we can detect visually and in other ways. Such signals have sometimes been associated with significant and dynamic weather phenomena. Ohio's Serpent Mound and associated regions, or those now occupied by the Hopi Indian Nation, formerly an ancient Anasazi site, or areas of the current and earlier Mayan Nations, or the Nazca Plateau of Peru, may generate signals correlating with climate change, that may impact our technology, as in major power blackouts.

  16. Floridas Miami Tequesta Indian Site, Its Calusa Indian Locations, the Matacumbe Keys, and Orlandos Wikiwa Springs Generate Environmentally Significant EMFs.

    NASA Astrophysics Data System (ADS)

    Mac Dougall, Jean S.; Mc Leod, Roger D.; Mc Leod, David M.

    2003-10-01

    Florida purchased the Tequesta ([Langue] doc Christ Spirit-signal) Indian site along the Miami River site that vigorously pulsates with even minor rainstorms entering or leaving the area. Although there is a laughable chimera of a fountain of youth associated with Ponce de Leons discovery of the Florida peninsula in about AD 1513, the Calusa (Royal Christ Jesus Spirit-signal) Indian Nation has an associated significance with EMF signals they possibly monitored throughout their area of activity. Our efforts have also led to the investigation of cultural and other influences implied by the Matacumbe Keys that indicate a shared commonality of awareness with Native Americans of the northeast such as Metacomet, or regions like Maines Grand Lake Matagamon and its associated electromagnetic Spirit Signal. Wikiwa Springs near Orlando shares much with Massachusetts (adherent of serpent Jesus Christ Spirit-signal) Natick, and New Hampshires Naticook Island. These are the locales of environmentally sensitive instrumentation.

  17. Teotihuacan and its influence in Mesoamerica. Archaeomagnetic studies

    NASA Astrophysics Data System (ADS)

    Terán, A.; Soler-Arechalde, A. M.

    2013-05-01

    Teotihuacan located at the north of the Basin of Mexico was one of the most important metropolises of Mesoamerica between AD 300-500. The chronological information of the city and its neighborhoods is very important to understand its evolution. We present the results of the sampling at the Feathered Serpent Temple and E complex at La Ciudadela, a zone at the south area of the Pyramids of the Sun and the Moon. These results correspond with a stratigraphic sequence between the 50 BC to AD 500. Two ritual events related with the beginning and the end of the Xolalpan stage (AD325-AD545) were archaeomagnetic dated, events that had been observed too at Teopancazco, the neighborhood of the taylors located at the SE of the city, denoting the importance of them. The beginning of Xolalpan stage is related with the exile of a group of teotihuacan warriors that arrived to Tikal.

  18. Abundance and distribution of ultramafic microbreccia in Moses Rock dike - Quantitative application of mapping spectroscopy

    NASA Technical Reports Server (NTRS)

    Mustard, John F.; Pieters, Carle M.

    1987-01-01

    Data from the Airborne Imaging Spectrometer were used to map the distribution and abundance of the serpentized ultramafic microbreccia (SUM) component in the Moses Rock dike, which is a Tertiary diatreme located on the Colorado Plateau in Utah. The geologic setting and composition of Moses Rock dike are discussed together with its texture and the relationship to the bedrock of surface materials. These observations along with laboratory spectroscopic data are used to interpret surface mineralogy of the dike and the surrounding regions from the imaging spectometer data. The spatial distribution and the abundance of the primary surface components were calculated using a nonlinear model for the mixing of spectra from multicomponent surfaces. The derived SUM distribution and abundance data support McGetchin's (1968) model for the emplacement of Moses Rock dike as a fluidized system.

  19. Snakes as hazards: modelling risk by chasing chimpanzees.

    PubMed

    McGrew, William C

    2015-04-01

    Snakes are presumed to be hazards to primates, including humans, by the snake detection hypothesis (Isbell in J Hum Evol 51:1-35, 2006; Isbell, The fruit, the tree, and the serpent. Why we see so well, 2009). Quantitative, systematic data to test this idea are lacking for the behavioural ecology of living great apes and human foragers. An alternative proxy is snakes encountered by primatologists seeking, tracking, and observing wild chimpanzees. We present 4 years of such data from Mt. Assirik, Senegal. We encountered 14 species of snakes a total of 142 times. Almost two-thirds of encounters were with venomous snakes. Encounters occurred most often in forest and least often in grassland, and more often in the dry season. The hypothesis seems to be supported, if frequency of encounter reflects selective risk of morbidity or mortality. PMID:25600837

  20. S. Weir mitchell and his snakes: unraveling the "united web and woof of popular and scientific beliefs".

    PubMed

    Cervetti, Nancy

    2007-09-01

    Although best known as a nineteenth-century neurologist and creator of the rest cure, S. Weir Mitchell was one of the first Americans to engage in large-scale animal experimentation. In 1860 he published Researches Upon the Venom of the Rattlesnake, and in 1886, in collaboration with Dr. Edward T. Reichert, he published Researches Upon the Venoms of Poisonous Serpents. Yet, Mitchell's pioneering work in scientific medicine remains a little known aspect of his career. This essay, based mainly on primary source material, tells the story of Mitchell's medical education and research on venomous snakes in order to reveal the ways myth and metaphor influenced medicine as it was becoming a science. PMID:17629777

  1. Interaction of toxic venoms with the complement system

    PubMed Central

    Birdsey, Vanessa; Lindorfer, Jean; Gewurz, H.

    1971-01-01

    Thirty-nine venoms from various vertebrate and invertebrate species were tested for their ability to consume haemolytic complement (C) activity upon incubation in fresh guinea-pig serum. Nineteen had `anti-complementary' activity, and these were provisionally sorted into the following groups: Pattern I—exemplified by the Naja haje (Egyptian cobra) and six other Elapidae species (all cobras), which induced selective consumption of C3—C9, and led to formation of a stable C3—C9-consuming intermediate; Pattern II—exemplified by the Agkistrodon rhodostoma (Malayan pit viper), Bitis arietans (puff adder), Bothrops jararaca (South American pit viper), Bothrops atrox (Fer de Lance) and three other species, which induced marked consumption of C4 and C2, as well as C3—C9, but did not form a stable C3—C9-consuming intermediate; and individual animals, e.g. the Lachesis muta (bushmaster), which induced other patterns (III—VI) of complement component consumption. Active fractions of representative venoms were partially purified by ion exchange and gel filtration chromatography and their interactions with the complement system characterized further. It is anticipated that these enzymes, with a capacity to activate the complement system in unique ways, will prove to be of further experimental usefulness. PMID:4398349

  2. Effects of Schizolobium parahyba Extract on Experimental Bothrops Venom-Induced Acute Kidney Injury

    PubMed Central

    Martines, Monique Silva; Mendes, Mirian M.; Shimizu, Maria H. M.; Melo Rodrigues, Veridiana; de Castro, Isac; Filho, Sebastião R. Ferreira; Malheiros, Denise M. A. C.; Yu, Luis; Burdmann, Emmanuel A.

    2014-01-01

    Background Venom-induced acute kidney injury (AKI) is a frequent complication of Bothrops snakebite with relevant morbidity and mortality. The aim of this study was to assess the effects of Schizolobium parahyba (SP) extract, a natural medicine with presumed anti-Bothrops venom effects, in an experimental model of Bothrops jararaca venom (BV)-induced AKI. Methodology Groups of 8 to 10 rats received infusions of 0.9% saline (control, C), SP 2 mg/kg, BV 0.25 mg/kg and BV immediately followed by SP (treatment, T) in the doses already described. After the respective infusions, animals were assessed for their glomerular filtration rate (GFR, inulin clearance), renal blood flow (RBF, Doppler), blood pressure (BP, intra-arterial transducer), renal vascular resistance (RVR), urinary osmolality (UO, freezing point), urinary neutrophil gelatinase-associated lipocalin (NGAL, enzyme-linked immunosorbent assay [ELISA]), lactate dehydrogenase (LDH, kinetic method), hematocrit (Hct, microhematocrit), fibrinogen (Fi, Klauss modified) and blinded renal histology (acute tubular necrosis score). Principal Findings BV caused significant decreases in GFR, RBF, UO, HcT and Fi; significant increases in RVR, NGAL and LDH; and acute tubular necrosis. SP did not prevent these changes; instead, it caused a significant decrease in GFR when used alone. Conclusion SP administered simultaneously with BV, in an approximate 10?1 concentration, did not prevent BV-induced AKI, hemolysis and fibrinogen consumption. SP used alone caused a decrease in GFR. PMID:24551041

  3. Preclinical assessment of the neutralizing capacity of antivenoms produced in six Latin American countries against medically-relevant Bothrops snake venoms.

    PubMed

    Segura, A; Castillo, M C; Núñez, V; Yarlequé, A; Gonçalves, L R C; Villalta, M; Bonilla, C; Herrera, M; Vargas, M; Fernández, M; Yano, M Y; Araújo, H P; Boller, M A A; León, P; Tintaya, B; Sano-Martins, I S; Gómez, A; Fernández, G P; Geoghegan, P; Higashi, H G; León, G; Gutiérrez, J M

    2010-11-01

    Species of the genus Bothrops induce the vast majority of snakebite envenomings in Latin America. A preclinical study was performed in the context of a regional network of public laboratories involved in the production, quality control and development of antivenoms in Latin America. The ability of seven polyspecific antivenoms, produced in Argentina, Brazil, Peru, Bolivia, Colombia and Costa Rica, to neutralize lethal, hemorrhagic, coagulant, defibrinogenating and myotoxic activities of the venoms of Bothrops neuwiedi (diporus) (Argentina), Bothrops jararaca (Brazil), B. neuwiedi (mattogrossensis) (Bolivia), Bothrops atrox (Peru and Colombia) and Bothrops asper (Costa Rica) was assessed using standard laboratory tests. Despite differences in the venom mixtures used in the immunization of animals for the production of these antivenoms, a pattern of extensive cross-neutralization was observed between these antivenoms and all the venoms tested, with quantitative differences in the values of effective doses. This study reveals the capacity of these antivenoms to neutralize, in preclinical tests, homologous and heterologous Bothrops venoms in Central and South America, and also highlight quantitative differences in the values of Median Effective Doses (ED50s) between the various antivenoms. PMID:20621114

  4. Purification and renal effects of phospholipase A(2) isolated from Bothrops insularis venom.

    PubMed

    Machado Braga, Marcus Davis; Costa Martins, Alice Maria; Alves, Claudênio Diógenes; de Menezes, Dalgimar Beserra; Martins, René Duarte; Ferreira Barbosa, Paulo Sérgio; de Sousa Oliveira, Isadora Maria; Toyama, Marcos Hikari; Toyama, Daniela Oliveira; Dos Santos Diz Filho, Eduardo Brito; Ramos Fagundes, Fabio Henrique; Fonteles, Manassés Claudino; Azul Monteiro, Helena Serra

    2008-02-01

    Bothrops insularis venom contains a variety of substances presumably responsible for several pharmacological effects. We investigated the biochemical and biological effects of phospholipase A(2) protein isolated from B. insularis venom and the chromatographic profile showed 7 main fractions and the main phospholipase A(2) (PLA(2)) enzymatic activity was detected in fractions IV and V. Fraction IV was submitted to a new chromatographic procedure on ion exchange chromatography, which allowed the elution of 5 main fractions designated as IV-1 to IV-5, from which IV-4 constituted the main fraction. The molecular homogeneity of this fraction was characterized by high-performance liquid chromatography (HPLC) and demonstrated by mass spectrometry (MS), which showed a molecular mass of 13984.20 Da; its N-terminal sequence presented a high amino acid identity (up to 95%) with the PLA(2) of Bothrops jararaca and Bothrops asper. Phospholipase A(2) isolated from B. insularis (Bi PLA(2) ) venom (10 microg/mL) was also studied as to its effect on the renal function of isolated perfused kidneys of Wistar rats (n=6). Bi PLA(2) increased perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF) and glomerular filtration rate (GFR). Sodium (%TNa(+)) and chloride tubular reabsorption (%TCl(-)) decreased at 120 min, without alteration in potassium transport. In conclusion, PLA(2) isolated from B. insularis venom promoted renal alterations in the isolated perfused rat kidney. PMID:17953979

  5. Determination of Toxic Activities in Bothrops spp. Snake Venoms Using Animal-Free Approaches: Correlation Between In Vitro Versus In Vivo Assays.

    PubMed

    de Souza, Letícia Lopes; Stransky, Stephanie; Guerra-Duarte, Clara; Flor-Sá, Ana; Schneider, Francisco Santos; Kalapothakis, Evanguedes; Chávez-Olórtegui, Carlos

    2015-10-01

    The main purpose of this study is to investigate the in vitro toxic effects of 5 Bothrops spp. snake venoms, which are part of the antigenic mixture used for the production of Brazilian antivenom, and evaluate their correlation with the in vivo toxic activities of Bothrops spp. venoms. The correlation analysis could be helpful for the replacement of living animals experimentation for in vitro bioassay. Cytotoxicity, L-amino acid oxidase (LAAO), proteolitic (serine and metalloproteinase), hyaluronidase (Hyal), and phospholipase A2 (PLA2) activities were estimated and the correlation coefficient was determined for each activity in relation to lethality, edema, hemorrhage and necrosis induced in live animals by B. jararaca, B. alternatus, B. jararacussu, B. neuwiedi, and B. moojeni venoms. The lethal activity in mice was highly related to Hyal activity (r = 0.94, p < .05), edema related to PLA2 activity (r = 0.94, p < .05), whereas the necrotizing activity showed high correlation with LAAO activity (r = 0.83, p < .05). A very significant correlation between in vitro cytotoxicity and LAAO activities was also observed (r = 0.97, p < .05). PMID:26160116

  6. Angiotensin-converting enzyme and enkephalinase in human breast cyst fluid.

    PubMed Central

    Frame, K. L.; Patton, K.; Reed, M. J.; Ghilchik, M. W.; Parish, D. C.

    1996-01-01

    Palpable breast cysts with an apocrine epithelial lining (type 1) are reported to be associated with a higher risk of developing breast cancer. The composition of breast cyst fluid (BCF) might include those factors involved in this increased risk. In this study peptidase activities that were active against the substrate [125I]metenkephalin-Arg-Phe were detected in BCF. The products were identified by reversed phase high-performance liquid chromatography (HPLC) as [125I]Tyr-Gly-Gly and [125I]Met-enkephalin. This proteolysis was not inhibited by PCMB, pepstatin A, leupeptin or aprotinin but was by EDTA, showing that the activity was due to metalloproteases. The production of [125I]Try-Gly-Gly was inhibited by phosphoramidon and thiorphan, whereas that of [125I]met-enkephalin was inhibited by captopril and Bothrops jararaca peptide, indicating that these activities are enkephalinase and angiotensin-converting enzyme (ACE) respectively. A fluorometric assay for ACE demonstrated that ACE levels are significantly higher in type 2 BCF than in type 1 BCF (30.8 vs 6.1 nmol hr-1 10 microliters-1, P < 0.001). As the increased risk of cancer is linked to type 1 cysts it is possible that higher levels of peptidase in type 2 BCF reflect a protective environment in the breast in which mitogenic peptide growth factors are neutralised by proteolysis. PMID:8795586

  7. A Complex-Geometry Validation Experiment for Advanced Neutron Transport Codes

    SciTech Connect

    David W. Nigg; Anthony W. LaPorta; Joseph W. Nielsen; James Parry; Mark D. DeHart; Samuel E. Bays; William F. Skerjanc

    2013-11-01

    The Idaho National Laboratory (INL) has initiated a focused effort to upgrade legacy computational reactor physics software tools and protocols used for support of core fuel management and experiment management in the Advanced Test Reactor (ATR) and its companion critical facility (ATRC) at the INL.. This will be accomplished through the introduction of modern high-fidelity computational software and protocols, with appropriate new Verification and Validation (V&V) protocols, over the next 12-18 months. Stochastic and deterministic transport theory based reactor physics codes and nuclear data packages that support this effort include MCNP5[1], SCALE/KENO6[2], HELIOS[3], SCALE/NEWT[2], and ATTILA[4]. Furthermore, a capability for sensitivity analysis and uncertainty quantification based on the TSUNAMI[5] system has also been implemented. Finally, we are also evaluating the Serpent[6] and MC21[7] codes, as additional verification tools in the near term as well as for possible applications to full three-dimensional Monte Carlo based fuel management modeling in the longer term. On the experimental side, several new benchmark-quality code validation measurements based on neutron activation spectrometry have been conducted using the ATRC. Results for the first four experiments, focused on neutron spectrum measurements within the Northwest Large In-Pile Tube (NW LIPT) and in the core fuel elements surrounding the NW LIPT and the diametrically opposite Southeast IPT have been reported [8,9]. A fifth, very recent, experiment focused on detailed measurements of the element-to-element core power distribution is summarized here and examples of the use of the measured data for validation of corresponding MCNP5, HELIOS, NEWT, and Serpent computational models using modern least-square adjustment methods are provided.

  8. The internal mystery plays: the role and physiology of the visual system in contemplative practices.

    PubMed

    Reader, A L

    1995-09-01

    In summary, the "White Light" and the imagery reported in contemplative practices appears to be a complex system of reflexes that mediate ischemia to the cerebral cortex, stimulating "release" of the occipital poles and the rostral midbrain to discharge these images in any profound state of cellular agony. These vascular events are mediated by way of the autonomic nervous system, either accidentally or purposefully, thus acquiring a near-death experience. Understanding the mechanism of the reflexes has taken many years and thousands of researchers to elucidate. In spite of these discoveries and those yet to come, no one will ever fully know why these reflexes and the sensations associated with them exist, or why they cause such profound psychic, physical, and spiritual changes in the individuals who have them. At this point, I can only be humbled by the process that has brought me to the paradigm I have described. I only know that most of the connections and correlations expressed in this article were the product of some of those methods mentioned herein; therefore, I cannot, and will not, take credit for that portion provided by the Guiding Spirit. Thus, the internal mysteries of the brain will always hide the Inner Mysteries, although the heart will always have a way of finding the right answers. We have become the Uroboric serpent (the serpent that eats its tail), in that we have returned to the ancient Egyptians' way of considering the eye as the seat of the soul and the doorway into the Inner Mysteries of the religious experience. Now, we find t hat in many ways they were correct that the eye, through its physiology, is another key to understanding these Inner Mysteries. PMID:9419803

  9. Shocked lithologies at the Wanapitei impact structure, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Grieve, R. A. F.; Ber, T. J.

    1994-09-01

    The approx. 7.5 diameter Wanapitei impact structure (46 deg 45 min N; 80 deg 45 min W) lies entirely within Lake Wanapitei in central Ontario, Canada. Impact lithologies are known only from glacial float at the southern end of the lake. Over 50% of the impact lithologies recovered from this float can be classified as suevite, less than 20% as highly shocked and partially melted arkosic metasediments of the target rock Mississagi Formation or, possibly, the Serpent Formation and less than 20% as glassy impact melt rocks. An additional less than 5% of the samples have similarities to the suevite but have up to 50% glass clasts and are tentatively interpreted as fall-back material. The glassy impact melt rocks fall into two textural and mineralogical types: a perlitically fractured, colorless glass matrix variant, with microlites of hypersthene with up to 11.5% Al2O3 and a 'felted' matrix variant, with evidence of flow prior to the crystallization of tabular orthopyroxene. These melt glasses show chemical inhomogeneities on a microscopic scale, with areas of essentially SiO2, even when appearing optically homogeneous. They are similar in bulk composition for major elements, but the felted matrix variant is approx. 5x more enriched in Ni, Co and Cr, the interelement ratios of which are indicative of an admixture of a chondritic projectile. Mixing models suggest that the glassy impact melt rocks can be made from the target rocks in the proportions: approx. 55% Gowganda wacke, approx. 42% Serpent arkose and approx. 3% Nipissing intrusives. Geologic reconstructions suggest that this is a reasonable mixture of potential target rocks at the time of impact.

  10. Capillary damage in the area postrema by venom of the northern black-tailed rattlesnake (Crotalus molossus molossus)

    PubMed Central

    Meléndez-Martínez, David; Macias-Rodríguez, Eduardo; Vargas-Caraveo, Alejandra; Martínez-Martínez, Alejandro; Gatica-Colima, Ana; Plenge-Tellechea, Luis Fernando

    2014-01-01

    The Northern black-tailed rattlesnake (Crotalus molossus molossus) venom is mainly hemotoxic, hemorrhagic, and neurotoxic. Its effects in the central nervous system are unknown and only poorly described for all Viperidae species in general. This is why we are interested in describe the damage induced by C. m. molossus venom in rat brain, particularly in the area postrema capillaries. Four C. m. molossus venom doses were tested (0.02, 0.05, 0.10 and 0.20mg/kg) injected intramuscularly at the lower limb, incubated by 24 hours and the brains were harvested. Area postrema coronal sections were stained with Haematoxylin and Eosin, and examined to observe the venom effect in quantity of capillaries and porphology. Starting from the 0.10mg/kg treatment we observed lysed extravasated erythrocytes and also capillary breakdown, as a consequence of hemorrhages appearance. The number of capillaries decreased significantly in response to the venom dose increment. Hemorrhages could be caused by the metalloproteinase activity on the basal membrane and the apoptosis generated by L-amino acid oxidases. Hemolysis could be caused by phospholipase A2 hemotoxic effect. We conclude that C. m. molossus crude venom produces hemolysis, capillary breakdown, hemorrhages, and the reduction in number of capillaries in the area postrema. PMID:25035793

  11. Complete mitochondrial DNA sequences of six snakes: phylogenetic relationships and molecular evolution of genomic features.

    PubMed

    Dong, Songyu; Kumazawa, Yoshinori

    2005-07-01

    Complete mitochondrial DNA (mtDNA) sequences were determined for representative species from six snake families: the acrochordid little file snake, the bold boa constrictor, the cylindrophiid red pipe snake, the viperid himehabu, the pythonid ball python, and the xenopeltid sunbeam snake. Thirteen protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 2 control regions were identified in these mtDNAs. Duplication of the control region and translocation of the tRNALeu gene were two notable features of the snake mtDNAs. The duplicate control regions had nearly identical nucleotide sequences within species but they were divergent among species, suggesting concerted sequence evolution of the two control regions. In addition, the duplicate control regions appear to have facilitated an interchange of some flanking tRNA genes in the viperid lineage. Phylogenetic analyses were conducted using a large number of sites (9570 sites in total) derived from the complete mtDNA sequences. Our data strongly suggested a new phylogenetic relationship among the major families of snakes: ((((Viperidae, Colubridae), Acrochordidae), (((Pythonidae, Xenopeltidae), Cylindrophiidae), Boidae)), Leptotyphlopidae). This conclusion was distinct from a widely accepted view based on morphological characters in denying the sister-group relationship of boids and pythonids, as well as the basal divergence of nonmacrostomatan cylindrophiids. These results imply the significance to reconstruct the snake phylogeny with ample molecular data, such as those from complete mtDNA sequences. PMID:16007493

  12. Isolation and Biochemical Characterization of a New Thrombin-Like Serine Protease from Bothrops pirajai Snake Venom

    PubMed Central

    Zaqueo, Kayena D.; Kayano, Anderson M.; Simões-Silva, Rodrigo; Moreira-Dill, Leandro S.; Fernandes, Carla F. C.; Fuly, André L.; Maltarollo, Vinícius G.; Honório, Kathia M.; da Silva, Saulo L.; Acosta, Gerardo; Caballol, Maria Antonia O.; de Oliveira, Eliandre; Albericio, Fernando; Calderon, Leonardo A.; Soares, Andreimar M.; Stábeli, Rodrigo G.

    2014-01-01

    This paper presents a novel serine protease (SP) isolated from Bothrops pirajai, a venomous snake found solely in Brazil that belongs to the Viperidae family. The identified SP, named BpirSP-39, was isolated by three chromatographic steps (size exclusion, bioaffinity, and reverse phase chromatographies). The molecular mass of BpirSP-39 was estimated by SDS-PAGE and confirmed by mass spectrometry (39,408.32?Da). The protein was able to form fibrin networks, which was not observed in the presence of serine protease inhibitors, such as phenylmethylsulfonyl fluoride (PMSF). Furthermore, BpirSP-39 presented considerable thermal stability and was apparently able to activate factor XIII of the blood coagulation cascade, unlike most serine proteases. BpirSP-39 was capable of hydrolyzing different chromogenic substrates tested (S-2222, S-2302, and S-2238) while Cu2+ significantly diminished BspirSP-39 activity on the three tested substrates. The enzyme promoted platelet aggregation and also exhibited fibrinogenolytic, fibrinolytic, gelatinolytic, and amidolytic activities. The multiple alignment showed high sequence similarity to other thrombin-like enzymes from snake venoms. These results allow us to conclude that a new SP was isolated from Bothrops pirajai snake venom. PMID:24719874

  13. Biochemical and enzymatic characterization of BpMP-I, a fibrinogenolytic metalloproteinase isolated from Bothropoides pauloensis snake venom.

    PubMed

    Naves de Souza, Dayane L; Gomes, Mário Sérgio R; Ferreira, Francis Barbosa; Rodrigues, Renata Santos; Achê, David Collares; Richardson, Michael; Borges, Márcia Helena; Rodrigues, Veridiana M

    2012-02-01

    Snake Venom Metalloproteinases (SVMPs) are the most abundant components present in Viperidae venom. They are important in the induction of systemic alterations and local tissue damage after envenomation. In the present study, a metalloproteinase named BpMPI was isolated from Bothropoides pauloensis snake venom and its biochemical and enzymatic characteristics were determined. BpMPI was purified in two chromatography steps on ion exchange CM-Sepharose Fast flow and Sephacryl S-300. This protease was homogeneous on SDS-PAGE and showed a single chain polypeptide of 20kDa under non reducing conditions. The partial amino acid sequence of the enzyme showed high similarity with other SVMPs enzymes from snake venoms. BpMPI showed proteolytic activity upon azocasein and bovine fibrinogen and was inhibited by EDTA, 1,10 phenanthroline and ?-mercaptoethanol. Moreover, this enzyme showed stability at neutral and alkaline pH and it was inactivated at high temperatures. BpMPI was able to hydrolyze glandular and tissue kallikrein substrates, but was unable to act upon factor Xa and plasmin substrates. The enzyme did not induce local hemorrhage in the dorsal region of mice even at high doses. Taken together, our data showed that BpMP-I is in fact a fibrinogenolytic metalloproteinase and a non hemorrhagic enzyme. PMID:22008900

  14. Epithelium specific ETS transcription factor, ESE-3, of Protobothrops flavoviridis snake venom gland transactivates the promoters of venom phospholipase A2 isozyme genes.

    PubMed

    Nakamura, Hitomi; Murakami, Tatsuo; Hattori, Shosaku; Sakaki, Yoshiyuki; Ohkuri, Takatoshi; Chijiwa, Takahito; Ohno, Motonori; Oda-Ueda, Naoko

    2014-12-15

    Protobothrops flavoviridis (habu) (Crotalinae, Viperidae) is a Japanese venomous snake, and its venom contains the enzymes with a variety of physiological activities. The phospholipases A2 (PLA2s) are the major components and exert various toxic effects. They are expressed abundantly in the venom gland. It is thought that the venom gland-specific transcription factors play a key role for activation of PLA2 genes specifically expressed in the venom gland. Thus, the full-length cDNA library for P. flavoviridis venom gland after milking of the venom was made to explore the transcription factors therein. As a result, three cDNAs encoding epithelium-specific ETS transcription factors (ESE)-1, -2, and -3 were obtained. Among them, ESE-3 was specifically expressed in the venom gland and activated the proximal promoters of venom PLA2 genes, which are possibly regarded as the representatives of the venom gland-specific protein genes in P. flavoviridis. Interestingly, the binding specificity of ESE-3 to the ETS binding motif located near TATA box is well correlated with transcriptional activities for the venom PLA2 genes. This is the first report that venom gland-specific transcription factor could actually activate the promoters of the venom protein genes. PMID:25449102

  15. Jaguarundi (Puma yagouaroundi) (Geoffroy, 1803) (Carnivora, Felidae) food habits in a mosaic of Atlantic Rainforest and eucalypt plantations of southeastern Brazil.

    PubMed

    Tófoli, C F; Rohe, F; Setz, E Z F

    2009-08-01

    Food habits of jaguarundi (Puma yagouaroundi) (Geoffroy, 1803) (Carnivora, Felidae) were studied between November 2000 and November 2001, in a 24.9 km(2) area of secondary Atlantic Rainforest and eucalypt plantation, in the Serra de Paranapiacaba, São Paulo State, Brazil. Analyses of 26 fecal and regurgitate samples, obtained over a stretch of 570.1 km, showed the consumption of 19 prey items and 74 prey occurrences. Small mammals were the most frequent food item (42.5%), followed by birds (21%), reptiles (14%) and medium-sized mammals (3%). The percent occurrence (PO) suggests that the diet consisted mainly of small rodents (30%) and birds (21%). We recorded for the first time the predation of Viperidae snakes by P. yagouaroundi. Although having a large list of items and range of dietary niche breadths (Bsta = 0.76), our data show that jaguarundi prey mainly on small vertebrates (mammals, birds or reptiles), and even in tall tropical forests or eucalypt plantations, it preys mostly on animals that come to, or live on, the ground. PMID:19802447

  16. Scales microstructure of snakes from the Egyptian area.

    PubMed

    Allam, Ahmed A; Abo-Eleneen, Rasha E

    2012-11-01

    The morphology of many organisms seems to be related to the environments in which they live. Many snakes are so similar in their morphological patterns that it becomes quite difficult to distinguish any adaptive divergence that may have occurred. Many authors have suggested that the microstructure of the reptile's scales has important functional value. Herein, we investigate variations on the micromorphology of the external surface of dorsal scales on the head, the mid-body region (trunk), and the tail of Rhomphotyphlops braminus (Typhlopidae), Eryx jaculus (Boidae), Psammophis sibilans (Colubridae), Naja haje (Elapidae) and Echis carinatus (Viperidae). The specimens were metallized and analyzed by scanning electron microscopy. All species displayed unique dorsal scale surface microstructures of the investigated regions. The microstructural pattern of the scales of head, trunk, and tail differs in different species of these snakes. In conclusion, we detected ecomorphologic relationships between extant dorsal scale microstructures and snake microhabitat, enabling us to hypothesize that environmental pressures have significant influences not only on these animals' macrostructure, but also on its microstructure as well. PMID:23106563

  17. Purification and cloning of cysteine-rich proteins from Trimeresurus jerdonii and Naja atra venoms.

    PubMed

    Jin, Yang; Lu, Qiumin; Zhou, Xingding; Zhu, Shaowen; Li, Rui; Wang, Wanyu; Xiong, Yuliang

    2003-10-01

    Three 26 kDa proteins, named as TJ-CRVP, NA-CRVP1 and NA-CRVP2, were isolated from the venoms of Trimeresurus jerdonii and Naja atra, respectively. The N-terminal sequences of TJ-CRVP and NA-CRVPs were determined. These components were devoid of the enzymatic activities tested, such as phospholipase A(2), arginine esterase, proteolysis, L-amino acid oxidase, 5'nucleotidase, acetylcholinesterase. Furthermore, these three components did not have the following biological activities: coagulant and anticoagulant activities, lethal activity, myotoxicity, hemorrhagic activity, platelet aggregation and platelet aggregation-inhibiting activities. These proteins are named as cysteine-rich venom protein (CRVP) because their sequences showed high level of similarity with mammalian cysteine-rich secretory protein (CRISP) family. Recently, some CRISP-like proteins were also isolated from several different snake venoms, including Agkistrodon blomhoffi, Trimeresurus flavoviridis, Lanticauda semifascita and king cobra. We presumed that CRVP might be a common component in snake venoms. Of particular interest, phylogenetic analysis and sequence alignment showed that NA-CRVP1 and ophanin, both from elapid snakes, share higher similarity with CRVPs from Viperidae snakes. PMID:14529736

  18. Differentiation of Sex Chromosomes and Karyotype Characterisation in the Dragonsnake Xenodermus javanicus (Squamata: Xenodermatidae).

    PubMed

    Rovatsos, Michail; Johnson Pokorná, Martina; Kratochvíl, Lukáš

    2015-01-01

    Highly differentiated heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are a basic principle among advanced snakes of the lineage Colubroidea, while other snake lineages generally lack these characteristics. For the first time, we cytogenetically examined the dragonsnake, Xenodermus javanicus, a member of the family Xenodermatidae, which is phylogenetically nested between snake lineages with and without differentiated sex chromosomes. Although most snakes have a karyotype with a stable chromosomal number of 2n = 36, the dragonsnake has an unusual, derived karyotype with 2n = 32 chromosomes. We found that heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are present in the dragonsnake, which suggests that the emergence of a highly differentiated W sex chromosome within snakes predates the split of Xenodermatidae and the clade including families Pareatidae, Viperidae, Homalopsidae, Lamprophiidae, Elapidae, and Colubridae. Although accumulations of interstitial telomeric sequences have not been previously reported in snakes, by using FISH with a telomeric probe we discovered them in 6 pairs of autosomes as well as in the W sex chromosome of the dragonsnake. Similarly to advanced snakes, the sex chromosomes of the dragonsnake have a significant accumulation of repeats containing a (GATA)n sequence. The results facilitate the dating of the differentiation of sex chromosomes within snakes back to the split between Xenodermatidae and other advanced snakes, i.e. around 40-75 mya. PMID:26575989

  19. Ophidian Spectaculitis and Spectacular Dysecdysis: A Histologic Description.

    PubMed

    Da Silva, M O; Bertelsen, M F; Heegaard, S; Garner, M M

    2015-11-01

    The histologic features of abnormal spectacles in 60 snakes from the 5 families of Boidae, Colubridae, Elapidae, Pythonidae, and Viperidae are described in a retrospective study conducted on specimens submitted to a private diagnostic service during a period of 15 years. Fifty-two snakes had inflammatory reactions in the spectacle. The stroma and outer epithelium of the spectacle were the layers most often involved in inflammatory disease. Lesions of the outer epithelium included edema, hyperkeratosis, and granulocyte infiltration occasionally with bacterial colonies and fungal elements. The stroma had infectious agents and inflammatory reactions in vessels and between the collagen fibrils. The inner epithelium had varying degrees of hyperplasia and hypertrophy, but no infectious agents were seen. Infectious agents in these cases included mites, bacterial disease, fungal disease, or a combination of bacterial and fungal disease. Special stains identified the bacteria most commonly involved to be Gram-positive cocci. Thirteen snakes had dysecdysis of the spectacle. Of these, 5 displayed a concurrent inflammatory reaction of the spectacle, while the remaining 8 snakes had extra keratin layers on a spectacle with an otherwise normal appearance. These keratin layers were attached to serocellular crusts located on the inner surface of the periocular scales. The cause for dyskeratotic lesions of the spectacle was not always apparent, and concurrent acariasis, other forms of dermatitis, trauma, suboptimal husbandry, and visceral disease were considered possible contributing factors. It was notable that only 4% of the submitted cases were found to have spectaculitis and/or spectacular dysecdysis. PMID:26077780

  20. 'Offensive' snakes: cultural beliefs and practices related to snakebites in a Brazilian rural settlement

    PubMed Central

    2010-01-01

    This paper records the meaning of the term 'offense' and the folk knowledge related to local beliefs and practices of folk medicine that prevent and treat snake bites, as well as the implications for the conservation of snakes in the county of Pedra Branca, Bahia State, Brazil. The data was recorded from September to November 2006 by means of open-ended interviews performed with 74 individuals of both genders, whose ages ranged from 4 to 89 years old. The results show that the local terms biting, stinging and pricking are synonymous and used as equivalent to offending. All these terms mean to attack. A total of 23 types of 'snakes' were recorded, based on their local names. Four of them are Viperidae, which were considered the most dangerous to humans, besides causing more aversion and fear in the population. In general, local people have strong negative behavior towards snakes, killing them whenever possible. Until the antivenom was present and available, the locals used only charms, prayers and homemade remedies to treat or protect themselves and others from snake bites. Nowadays, people do not pay attention to these things because, basically, the antivenom is now easily obtained at regional hospitals. It is understood that the ethnozoological knowledge, customs and popular practices of the Pedra Branca inhabitants result in a valuable cultural resource which should be considered in every discussion regarding public health, sanitation and practices of traditional medicine, as well as in faunistic studies and conservation strategies for local biological diversity. PMID:20346120

  1. BbMP-1, a new metalloproteinase isolated from Bothrops brazili snake venom with in vitro antiplasmodial properties.

    PubMed

    Kayano, Anderson M; Simões-Silva, Rodrigo; Medeiros, Patrícia S M; Maltarollo, Vinícius G; Honorio, Kathia M; Oliveira, Eliandre; Albericio, Fernando; da Silva, Saulo L; Aguiar, Anna Caroline C; Krettli, Antoniana U; Fernandes, Carla F C; Zuliani, Juliana P; Calderon, Leonardo A; Stábeli, Rodrigo G; Soares, Andreimar M

    2015-11-01

    This study describes the biochemical and functional characterization of a new metalloproteinase named BbMP-1, isolated from Bothrops brazili venom. BbMP-1 was homogeneous on SDS-PAGE, presented molecular mass of 22,933Da and pI 6.4. The primary structure was partially elucidated with high identity with others metalloproteinases from Viperidae venoms. The enzymatic activity on azocasein was evaluated in different experimental conditions (pH, temperature). A significant reduction in enzyme activity after exposure to chelators of divalent cations (EDTA), reducing agents (DTT), pH less than 5.0 or temperatures higher than 45 °C was observed. BbMP-1 showed activity on fibrinogen degrading A? chain quickly and to a lesser extent the B? chain. Also demostrated to be weakly hemorrhagic, presenting however, significant myotoxic and edematogenic activity. The in vitro activity of BbMP-1 against Plasmodium falciparum showed an IC50 of 3.2 ± 2.0 ?g/mL. This study may help to understand the pathophysiological effects induced by this group of toxin and their participation in the symptoms observed in cases of snake envenomation. Moreover, this result is representative for this group of proteins and shows the biotechnological potential of BbMP-1 by the demonstration of its antiplasmodial activity. PMID:26363289

  2. The effects of selected Australian snake venoms on tumour-associated microvascular endothelial cells (TAMECs) in vitro

    PubMed Central

    Bateman, Emma; Venning, Michael; Mirtschin, Peter; Woods, Anthony

    2013-01-01

    The effects of various viperid and elapid venoms on the cellular biology of tumour-associated microvascular endothelial cells (TAMECs) were determined in the current study using cells isolated from a rat mammary adenocarcinoma. Previous studies to determine the effects of snake venoms on endothelial cells in vitro have in the main been performed on either human umbilical vein endothelial cells (HUVECs), bovine aortic endothelial cells (BAECs) or endothelial cell lines. These cell populations are accessible and easy to maintain in culture, however, it is well established that endothelial cells display vast heterogeneity depending upon the local microenvironment of the tissue from which they are isolated. Vascular targeting agents have been isolated from a variety of snake venoms, particularly from snakes of the Viperidae family, but it is yet to be established to what extent the venoms from Australian elapids possess similar vascular targeting properties. The present study used endothelial cells (ECs) isolated from the microvasculature of a rat mammary adenocarcinoma to determine the effects of a panel of snake venoms, including viperid venoms with known apoptotic activity and elapid venoms (both exotic and indigenous to Australia), on endothelial morphology and viability, paying specific attention to apoptotic responses. Three of the five Australian snake venoms investigated in this study elicited significant apoptotic responses in ECs which were in many ways similar to responses elicited by the selected viperid venoms. This suggests that these Australian elapids may possess vascular targeting components similar to those found within viperid venoms. PMID:24191190

  3. Pathophysiological effects of Cerastes cerastes and Vipera lebetina venoms: Immunoneutralization using anti-native and anti-(60)Co irradiated venoms.

    PubMed

    Boumaiza, Sabrina; Oussedik-Oumehdi, Habiba; Laraba-Djebari, Fatima

    2016-01-01

    Cerastes cerastes and Vipera lebetina are the most medically important vipers in Algeria. Their bite induces several pathological effects on victims of accidental envenomation. In this study we analyzed the pathogenesis induced after an experimental envenomation. Indeed, we determined, in vitro, venom enzymatic activities and we analyzed, in vivo, pathological effects induced on liver, heart, lung and skin. In addition we investigated the neutralizing potency of four experimental antivenoms elicited against native and irradiated venoms. Results revealed that V. lebetina and Cerastes cerastes venoms presented strong hemorrhagic, oedematic and necrotic activities. Histopathological study showed that both venoms induced deep damage in tissue structures leading to organ dysfunction. They also increased cellular peroxidases activities, indicating an inflammatory process that is known to amplify tissue damage. Western-blot analysis evidenced that anti-irradiated venoms recognized most components of native venoms. Antivenoms were effective in neutralizing all tested activities, with an increased protective effect obtained with anti-irradiated venoms. Anti-irradiated venoms reduced cellular peroxidases activities indicating a reduction of the inflammatory response. These results may improve our understanding of Algerian Viperidae bite pathogenesis and would encourage further studies planning to provide more proofs on the effectiveness of anti-irradiated venoms administration in the treatment of envenomation. PMID:26678662

  4. Phospholipase A2 enhances the endothelial cell detachment effect of a snake venom metalloproteinase in the absence of catalysis.

    PubMed

    Bustillo, Soledad; García-Denegri, María Emilia; Gay, Carolina; Van de Velde, Andrea C; Acosta, Ofelia; Angulo, Yamileth; Lomonte, Bruno; Gutiérrez, José María; Leiva, Laura

    2015-10-01

    Microvessel disruption leading to hemorrhage stands among the most dangerous consequences of envenomings by snakes of the family Viperidae. A PIII metalloproteinase (SVMP), balteragin, purified from the venom of the snake Bothrops alternatus, displays a potent hemorrhagic effect, and a moderate myotoxicity in vivo. Previous studies described the ability of this SVMP to induce the detachment of C2C12 myoblasts in culture, without causing cytolysis. Surprisingly, a purified acidic phospholipase A2 (PLA2) from the same venom was found to increase this detaching activity of the SVMP on myoblasts. Since endothelial cells are a natural target of SVMPs in vivo, the possibility that this synergistic effect is also observed on this cell type was explored in the present work. In addition, a first approach of the mechanism of action of this effect was studied. Results clearly confirm that the acidic PLA2, despite lacking toxicity towards endothelial cells, significantly enhances the detaching effect of the SVMP even at a concentration as low as 1 ?g/mL. Inhibition of enzymatic activity of the PLA2 by chemical modification with p-bromophenacyl bromide did not affect the synergistic activity, suggesting that this effect is not dependent on phospholipase enzymatic activity and may instead be the consequence of an interaction of the PLA2 with endothelial cell plasma membrane. To our knowledge, this is the first report of a synergistic action of a non toxic PLA2 in enhancing the detachment of endothelial cells induced by a metalloproteinase. PMID:26279213

  5. Small serum protein-1 changes the susceptibility of an apoptosis-inducing metalloproteinase HV1 to a metalloproteinase inhibitor in habu snake (Trimeresurus flavoviridis)

    PubMed Central

    Shioi, Narumi; Ogawa, Eiki; Mizukami, Yuki; Abe, Shuhei; Hayashi, Rieko; Terada, Shigeyuki

    2013-01-01

    Viperidae snakes containing various venomous proteins also have several anti-toxic proteins in their sera. However, the physiological function of serum protein has been elucidated incompletely. Small serum protein (SSP)-1 is a major component of the SSPs isolated from the serum of a Japanese viper, the habu snake (Trimeresurus flavoviridis). It exists in the blood as a binary complex with habu serum factor (HSF), a snake venom metalloproteinase inhibitor. Affinity chromatography of the venom on an SSP-1-immobilized column identified HV1, an apoptosis-inducing metalloproteinase, as the target protein of SSP-1. Biacore measurements revealed that SSP-1 was bound to HV1 with a dissociation constant of 8.2 × 10?8 M. However, SSP-1 did not inhibit the peptidase activity of HV1. Although HSF alone showed no inhibitory activity or binding affinity to HV1, the SSP-1–HSF binary complex bound to HV1 formed a ternary complex that non-competitively inhibited the peptidase activity of HV1 with a inhibition constant of 5.1 ± 1.3 × 10?9 M. The SSP-1–HSF complex also effectively suppressed the apoptosis of vascular endothelial cells and caspase 3 activation induced by HV1. Thus, SSP-1 is a unique protein that non-covalently attaches to HV1 and changes its susceptibility to HSF. PMID:23100271

  6. Evolutionary stability of sex chromosomes in snakes.

    PubMed

    Rovatsos, Michail; Vukić, Jasna; Lymberakis, Petros; Kratochvíl, Lukáš

    2015-12-22

    Amniote vertebrates possess various mechanisms of sex determination, but their variability is not equally distributed. The large evolutionary stability of sex chromosomes in viviparous mammals and birds was believed to be connected with their endothermy. However, some ectotherm lineages seem to be comparably conserved in sex determination, but previously there was a lack of molecular evidence to confirm this. Here, we document a stability of sex chromosomes in advanced snakes based on the testing of Z-specificity of genes using quantitative PCR (qPCR) across 37 snake species (our qPCR technique is suitable for molecular sexing in potentially all advanced snakes). We discovered that at least part of sex chromosomes is homologous across all families of caenophidian snakes (Acrochordidae, Xenodermatidae, Pareatidae, Viperidae, Homalopsidae, Colubridae, Elapidae and Lamprophiidae). The emergence of differentiated sex chromosomes can be dated back to about 60 Ma and preceded the extensive diversification of advanced snakes, the group with more than 3000 species. The Z-specific genes of caenophidian snakes are (pseudo)autosomal in the members of the snake families Pythonidae, Xenopeltidae, Boidae, Erycidae and Sanziniidae, as well as in outgroups with differentiated sex chromosomes such as monitor lizards, iguanas and chameleons. Along with iguanas, advanced snakes are therefore another example of ectothermic amniotes with a long-term stability of sex chromosomes comparable with endotherms. PMID:26702042

  7. Snake richness in urban forest fragments from Niterói and surroundings, state of Rio de Janeiro, southeastern Brazil

    PubMed Central

    Citeli, Nathalie; Hamdan, Breno

    2016-01-01

    Abstract Background The Atlantic Forest is a hotspot for biodiversity, an area which houses high species richness and endemism, but with high level of threat. With reference to the herpetofauna, until recently there has been no detailed information regarding diversity of snakes recorded in the Atlantic Forest, the number of endemic species and their distribution ranges. While these basic data were missing, large areas of original forest have continued to be lost to increased urbanization and human population, representing a severe threat to the biodiversity. New information We recorded 28 snake species in our study area. Dipsadidae was the richest family with 14 species, followed by Colubridae (eight species), Boidae (two species), Viperidae (two species), and Anomalepididae, Elapidae and Typhlopidae (one species each). Most species were forest inhabitants (61%), of which 13 are endemic to the Atlantic Forest. There were no clearly defined species clusters regarding species composition. None of the species recorded in Niterói are listed as threatened in the Brazilian Redlist. However, most of them are strongly associated with forested areas and, perhaps, are not adapted to live in small fragments. Thus, more initiatives should be implemented to evaluate the true conservation status of these species in order to better protect them. PMID:26929711

  8. Current challenges for confronting the public health problem of snakebite envenoming in Central America

    PubMed Central

    2014-01-01

    Snakebite envenoming is a serious public health problem in Central America, where approximately 5,500 cases occur every year. Panama has the highest incidence and El Salvador the lowest. The majority, and most severe, cases are inflicted by the pit viper Bothrops asper (family Viperidae), locally known as ‘terciopelo’, ‘barba amarilla’ or ‘equis’. About 1% of the bites are caused by coral snakes of the genus Micrurus (family Elapidae). Despite significant and successful efforts in Central America regarding snakebite envenomings in the areas of research, antivenom manufacture and quality control, training of health professionals in the diagnosis and clinical management of bites, and prevention of snakebites, much remains to be done in order to further reduce the impact of this medical condition. This essay presents seven challenges for improving the confrontation of snakebite envenoming in Central America. Overcoming these challenges demands a coordinated partnership of highly diverse stakeholders though inter-sectorial and inter-programmatic interventions. PMID:24602234

  9. Snakebite management in Iran: Devising a protocol

    PubMed Central

    Monzavi, Seyed Mostafa; Dadpour, Bita; Afshari, Reza

    2014-01-01

    Background: Snakebite in Iran has been a health concern. However, management of snakebite is not standardized and varies from center to center. This study is aimed at devising an evidence-based comprehensive protocol for snakebite management in Iran, to reduce unnecessary variations in practice. Materials and Methods: A narrative search in electronic databases was performed. Fifty peer-reviewed articles, guidelines, and textbooks were reviewed and practical details were extracted. Our currently used protocol in the Mashhad Toxicology Center was supplemented with this information. Consequently an improved wide-range protocol was developed. The protocol was then discussed and amended within a focus group comprised of medical toxicologists and internal medicine specialists. The amended version was finally discussed with expert physicians specialized in different areas of medicine, to be optimized by supplementing other specific considerations. Results: During a one-year process, the protocol was finalized. The final version of the protocol, which was designed in six steps, comprised of three components: A schematic algorithm, a severity grading scale, and instructions for supportive and adjunctive treatments. The algorithm pertains to both Viperidae and Elapidae snakebite envenomations and consists of a planned course of action and dosing of antivenom, based on the severity of the envenomation. Conclusion: Snakebite envenomation is a clinical toxicologic emergency, which needs to be treated in a timely and organized manner. Hence, a multi-aspect protocol was designed to improve the clinical outcomes, reduce unnecessary administration of antivenom, and help physicians make more proper clinical judgments. PMID:24778670

  10. Haematopoiesis and a new mechanism for the release of mature blood cells from the bone marrow into the circulation in snakes (Ophidia).

    PubMed

    Sano-Martins, I Sigueko; Dabrowski, Z; Tabarowski, Z; Witkowska-Pelc, E; Spadacci Morena, D Denelle; Spodaryk, K

    2002-10-01

    This is the first description of haematopoiesis in snakes. Studies were carried out on the following species belonging to Ophidia: Bothrops jararaca, Bothrops jararacusu, Waglerophis merremii, Elaphe taeniura taeniura, Boa constrictor,and Python reticulatus. Smears of the peripheral blood and histological preparations from the vertebrae, ribs, liver, and spleen were studied under a light and electron microscope. Myeloid cells were present in the following locations in the vertebrae: the neural spine, zygoapophysial processes, floor of the neural canal, lacunae in the bodies of vertebrae and also inside the ribs. Although the vascular system was well developed, especially around the ribs, vessels inside the marrow cavities were scarce, both in the ribs and elsewhere where haematopoiesis was found. Venous sinuses were well developed in the vertebrae and in the rib regions from their costal head towards the middle area. They consisted of one layer of fine endothelial cells. Mature cells in the process of migration into the general circulation were only sporadically encountered when venous sinuses were studied on perfusion-fixed specimens. In contrast, almost every sinus venosus contained protrusions directed towards the lumen, filled mostly with mature and immature blood cells. Various stages of their formation were seen in the cross sections of venous sinuses ranging from small, newly formed to large, elongated ones, filled with many fully developed and some maturing blood cells. In many cases the apices of the protrusions were ruptured, and mature blood cells, as well as a few immature ones, were seen in their vicinity. This observation led us to a new hypothesis that blood cells are released from the extravascular space into the lumen of venous sinuses. In snakes, these cells are released into the systemic circulation mainly via the rupture of protrusions filled with mature blood cells and, to a lesser degree, by transcytosis as known in mammals. In the spleens from young specimens, 1-2 foci of haematopoiesis were encountered where lymphopoiesis predominated. Haematopoiesis was not detected in the liver. PMID:12242485

  11. Role of cyclooxygenases in oedema-forming activity of bothropic venoms.

    PubMed

    Olivo, Renata do A; Teixeira, Catarina F P; Wallace, John L; Gutierrez, Jose M; Zamuner, Stella R

    2007-04-01

    The venoms of Bothrops asper (BaV) and Bothrops jararaca (BjV), two of the most medically important poisonous snakes of Latin America, cause pronounced oedema in the victims through poorly understood mechanisms. In the present study, we examined the possible role of cyclooxygenases (COX) in the genesis of mouse paw oedema caused by BaV and BjV injections. BaV at 2.5 microg/paw and BjV at 0.75 microg/paw induced significant oedema that persisted for up to 6h following subplantar injection. Treatment with indomethacin (2 mg/kg), rofecoxib, (10 mg/kg), or dexamethasone (2 mg/kg) significantly reduced the BaV- and BjV-induced oedema formation. Treatment with SC-560 (30 mg/kg) significantly reduced the oedema formation induced by BjV but had no effect on that induced by BaV. Both venoms induced significant increases in the levels of prostaglandin E(2) (PGE(2)) and the expression of COX-1 and COX-2 in paw tissue. The peak of oedema formation and PGE(2) release correlated with marked expression of COX-2 in the paw tissue. These results demonstrate that injection of BaV and BjV results in a rapid increase in oedema formation that is, at least partially, mediated by arachidonic acid metabolites formed by COX-2. In the case of BjV, COX-1-derived prostanoids also appear to contribute significantly to the inflammatory changes. PMID:17204299

  12. Effects induced by Apis mellifera venom and its components in experimental models of nociceptive and inflammatory pain.

    PubMed

    Merlo, Leonardo A; Bastos, Leandro F S; Godin, Adriana M; Rocha, Leonardo T S; Nascimento, Elias B; Paiva, André L L; Moraes-Santos, Tasso; Zumpano, Antônio A C; Bastos, Esther M A F; Heneine, Luiz Guilherme D; Coelho, Márcio M

    2011-04-01

    The effects induced by Apis mellifera venom (AMV), melittin-free AMV, fraction with molecular mass < 10 kDa (F<₁₀) or melittin in nociceptive and inflammatory pain models in mice were investigated. Subcutaneous administration of AMV (2, 4 or 6 mg/kg) or melittin-free AMV (1, 2 or 4 mg/kg) into the dorsum of mice inhibited both phases of formaldehyde-induced nociception. However, F<₁₀ (2, 4 or 6 mg/kg) or melittin (2 or 3 mg/kg) inhibited only the second phase. AMV (4 or 6 mg/kg), but not F<₁₀, melittin-free AMV or melittin, induced antinociception in the hot-plate model. Paw injection of AMV (0.05 or 0.10 mg), F<₁₀ (0.05 or 0.1 mg) or melittin (0.025 or 0.050 mg) induced a nociceptive response. In spite of inducing nociception after paw injection, scorpion (Tityus serrulatus) or snake (Bothrops jararaca) venom injected into the dorsum of mice did not inhibit formaldehyde-induced nociception. In addition, AMV (6 mg/kg), but not F<₁₀ (6 mg/kg) or melittin (3 mg/kg), inhibited formaldehyde paw oedema. Concluding, AMV, F<₁₀ and melittin induce two contrasting effects: nociception and antinociception. AMV antinociception involves the action of different components and does not result from non-specific activation of endogenous antinociceptive mechanisms activated by exposure to noxious stimuli. PMID:21333665

  13. A multifaceted analysis of viperid snake venoms by two-dimensional gel electrophoresis: an approach to understanding venom proteomics.

    PubMed

    Serrano, Solange M T; Shannon, John D; Wang, Deyu; Camargo, Antonio C M; Fox, Jay W

    2005-02-01

    The complexity of Viperid venoms has long been appreciated by investigators in the fields of toxinology and medicine. However, it is only recently that the depth of that complexity has become somewhat quantitatively and qualitatively appreciated. With the resurgence of two-dimensional gel electrophoresis (2-DE) and the advances in mass spectrometry virtually all venom components can be visualized and identified given sufficient effort and resources. Here we present the use of 2-DE for examining venom complexity as well as demonstrating interesting approaches to selectively delineate subpopulations of venom proteins based on particular characteristics of the proteins such as antibody cross-reactivity or enzymatic activities. 2-DE comparisons between venoms from different species of the same genus (Bothrops) of snake clearly demonstrated both the similarity as well as the apparent diversity among these venoms. Using liquid chromatography/tandem mass spectrometry we were able to identify regions of the two-dimensional gels from each venom in which certain classes of proteins were found. 2-DE was also used to compare venoms from Crotalus atrox and Bothrops jararaca. For these venoms a variety of staining/detection protocols was utilized to compare and contrast the venoms. Specifically, we used various stains to visualize subpopulations of the venom proteomes of these snakes, including Coomassie, Silver, Sypro Ruby and Pro-Q-Emerald. Using specific antibodies in Western blot analyses of 2-DE of the venoms we have examined subpopulations of proteins in these venoms including the serine proteinase proteome, the metalloproteinase proteome, and the phospholipases A2 proteome. A functional assessment of the gelatinolytic activity of these venoms was also performed by zymography. These approaches have given rise to a more thorough understanding of venom complexity and the toxins comprising these venoms and provide insights to investigators who wish to focus on these venom subpopulations of proteins in future studies. PMID:15627971

  14. Stable isotope tracer reveals that viviparous snakes transport amino acids to offspring during gestation.

    PubMed

    Van Dyke, James U; Beaupre, Steven J

    2012-03-01

    Viviparity and placentation have evolved from oviparity over 100 times in squamate reptiles (lizards and snakes). The independent origins of placentation have resulted in a variety of placental morphologies in different taxa, ranging from simple apposition of fetal and maternal tissues to endotheliochorial implantation that is homoplasious with mammalian placentation. Because the eggs of oviparous squamates transport gases and water from the environment and calcium from the eggshell, the placentae of viviparous squamates are thought to have initially evolved to accomplish these functions from within the maternal oviduct. Species with complex placentae have also been shown to rely substantially, or even primarily, on placental transport of organic nutrients for embryonic nutrition. However, it is unclear whether species with only simple placentae are also capable of transporting organic nutrients to offspring. Among viviparous squamates, all of the snakes that have been studied thus far have been shown to have simple placentae. However, most studies of snake placentation are limited to a single lineage, the North American Natricinae. We tested the abilities of four species of viviparous snakes - Agkistrodon contortrix (Viperidae), Boa constrictor (Boidae), Nerodia sipedon (Colubridae: Natricinae) and Thamnophis sirtalis (Colubridae: Natricinae) - to transport diet-derived amino acids to offspring during gestation. We fed [(15)N]leucine to pregnant snakes, and compared offspring (15)N content with that of unlabeled controls. Labeled females allocated significantly more (15)N to offspring than did controls, but (15)N allocation did not differ among species. Our results indicate that viviparous snakes are capable of transporting diet-derived amino acids to their offspring during gestation, possibly via placentation. PMID:22323198

  15. Structures of Azemiops feae venom phospholipases and cys-rich-secretory protein and implications for taxonomy and toxinology.

    PubMed

    Tsai, Inn-Ho; Wang, Ying-Ming; Huang, Kai-Fa

    2016-05-01

    The Azemiops snakes are pit-less and phylogenetically located at the Crotalinae and Viperinae divergence. cDNAs encoding five Azemiops venom phospholipase (sPLA2) molecules were cloned and sequenced; their signal-peptides were similar to those of crotalid sPLA2s. Based on their calculated pI-values and residue-49 substitutions, they were designated as Af-E6, Af-N49a, Af-N49a1, Af-N49a2, and Af-N49b, respectively. The first three isoforms, comprising 3-4% of the venom proteins, were purified by reversed-phase HPLC. Af-E6 is catalytically active and has >80% sequence-similarity to other Glu(6)-PLA2 (a pitviper venom-marker). Results of phylogenetic analyses reveal that acidic Af-N49a and Af-N49a1 are rather unique and loosely linked with crotalid PLA2s, while Af-N49b is related to the viperid PLA2s with Ser(1) substitution. Notably, the Asn(49)-substitutions in these molecules imply catalytic-independent mechanisms. The 3D-models of Af-E6 and Af-N49a have surface electropotential maps similar to each other and to those of antiplatelet PLA2s, while the Af-N49b model is similar to basic and myotoxic sPLA2 molecules. From Azemiops feae and four other Viperidae, we cloned five novel Cys-rich secretory proteins (CRISPs). Azemiops CRISP and natriuretic-peptide precursors share more sequence similarities with those of crotalid venoms than with viperid venoms, further supporting the theory that Azemiops are sister taxons to pit vipers, especially Tropedolaemus. PMID:26908291

  16. A new tyrosine-specific chymotrypsin-like and angiotensin-degrading serine proteinase from Vipera lebetina snake venom.

    PubMed

    Siigur, Ene; Tõnismägi, Külli; Trummal, Katrin; Samel, Mari; Vija, Heiki; Aaspõllu, Anu; Rönnholm, Gunilla; Subbi, Juhan; Kalkkinen, Nisse; Siigur, Jüri

    2011-02-01

    Vipera lebetina venom contains different metallo- and serine proteinases that affect coagulation and fibrin(ogen)olysis. A novel serine proteinase from V. Lebetina venom having ChymoTrypsin Like Proteolytic activity (VLCTLP) was purified to homogeneity from the venom using Sephadex G-100sf, DEAE-cellulose, heparin-agarose and FPLC on Superdex 75 chromatographies. VLCTLP is a glycosylated serine proteinase with a molecular mass of 41926 Da. It reacts with N-acetyl-L-tyrosine ethyl ester (ATEE) but not with Suc-Ala-Ala-Pro-Phe-pNA or Suc-Ala-Ala-Pro-Leu-pNA. The complete amino acid sequence of the VLCTLP is deduced from the nucleotide sequence of the cDNA encoding this protein. The full-length cDNA sequence of the VLCTLP encodes open reading frame of 257 amino acid residues that includes a putative signal peptide of 18 amino acids, a proposed activation peptide of six amino acid residues and serine proteinase of 233 amino acid residues. VLCTLP belongs to the S1 (chymotrypsin) subfamily of proteases. The multiple alignment of its deduced amino acid sequence showed structural similarity with other serine proteases from snake venoms. The protease weakly hydrolyses azocasein, A?-chain and more slowly B?-chain of fibrinogen. VLCTLP does not cleave fibrin and has no gelatinolytic activity. Specificity studies against peptide substrates (angiotensin I and II, oxidized insulin B-chain, glucagon, fibrinogen fragments etc.) showed that VLCTLP catalysed the cleavage of peptide bonds after tyrosine residues. VLCTLP is the only purified and characterized serine proteinase from snake venoms that catalyses ATEE hydrolysis. We detected ATEE-hydrolysing activities also in 9 different Viperidae and Crotalidae venoms. PMID:20950666

  17. Reproduction in female copperhead snakes (Agkistrodon contortrix): plasma steroid profiles during gestation and post-birth periods.

    PubMed

    Smith, Charles F; Schuett, Gordon W; Hoss, Shannon K

    2012-04-01

    We investigated levels of plasma progesterone (P4), 17?-estradiol (E2), testosterone (T), and corticosterone (CORT) during gestation and post-birth periods in wild-collected female copperhead snakes (Viperidae; Agkistrodon contortrix). We also sought to determine whether CORT levels at (or near) birth dramatically increase and were correlated with duration of labor and litter size. Specifically, pregnant subjects (N = 14) were collected during early- to mid-gestation, held in the laboratory, and repeatedly bled to obtain plasma for steroid analyses. Progesterone showed significant changes during gestation, with the highest levels at the onset of sampling (circa 50 days prior to birth); P4 progressively declined up to parturition, and basal levels were observed thereafter. At the onset of sampling, E2 was at peak levels and fell sharply at circa 30 days prior to birth, a trend observed throughout the post-birth sampling period. Throughout the entire sampling period, T was undetectable. Although CORT showed no significant changes during gestation and several days following parturition, there was a highly significant peak at the time of birth. Our findings mirror the results of previous studies on pregnancy and steroid hormones of other live-bearing snakes, lizards, and mammals. As expected, there was a significant relationship between duration of labor and litter size; however, although levels of CORT did not achieve significance, there was a positive trend with litter size. We suggest that elevation of CORT at birth is involved in the mobilization and regulation of energy stores necessary for the physiological process of parturition and as a possible mechanism to trigger birth. PMID:22468838

  18. African Adders: Partial Characterization of Snake Venoms from Three Bitis Species of Medical Importance and Their Neutralization by Experimental Equine Antivenoms

    PubMed Central

    Paixão-Cavalcante, Danielle; Kuniyoshi, Alexandre K.; Portaro, Fernanda C. V.; da Silva, Wilmar Dias; Tambourgi, Denise V.

    2015-01-01

    Background An alarming number of fatal accidents involving snakes are annually reported in Africa and most of the victims suffer from permanent local tissue damage and chronic disabilities. Envenomation by snakes belonging to the genus Bitis, Viperidae family, are common in Sub-Saharan Africa. The accidents are severe and the victims often have a poor prognosis due to the lack of effective specific therapies. In this study we have biochemically characterized venoms from three different species of Bitis, i.e., Bitis arietans, Bitis gabonica rhinoceros and Bitis nasicornis, involved in the majority of the human accidents in Africa, and analyzed the in vitro neutralizing ability of two experimental antivenoms. Methodology/Principal Findings The data indicate that all venoms presented phospholipase, hyaluronidase and fibrinogenolytic activities and cleaved efficiently the FRET substrate Abz-RPPGFSPFRQ-EDDnp and angiotensin I, generating angiotensin 1–7. Gelatinolytic activity was only observed in the venoms of B. arietans and B. nasicornis. The treatment of the venoms with protease inhibitors indicated that Bitis venoms possess metallo and serinoproteases enzymes, which may be involved in the different biological activities here evaluated. Experimental antivenoms produced against B. arietans venom or Bitis g. rhinoceros plus B. nasicornis venoms cross-reacted with the venoms from the three species and blocked, in different degrees, all the enzymatic activities in which they were tested. Conclusion These results suggest that the venoms of the three Bitis species, involved in accidents with humans in the Sub-Saharan Africa, contain a mixture of various enzymes that may act in the generation and development of some of the clinical manifestations of the envenomations. We also demonstrated that horse antivenoms produced against B. arietans or B. g. rhinoceros plus B. nasicornis venoms can blocked some of the toxic activities of these venoms. PMID:25643358

  19. Immunochemical and biological characterization of monoclonal antibodies against BaP1, a metalloproteinase from Bothrops asper snake venom.

    PubMed

    Fernandes, I; Assumpção, G G; Silveira, C R F; Faquim-Mauro, E L; Tanjoni, I; Carmona, A K; Alves, M F M; Takehara, H A; Rucavado, A; Ramos, O H P; Moura-da-Silva, A M; Gutiérrez, J M

    2010-11-01

    BaP1 is a P-I class of Snake Venom Metalloproteinase (SVMP) relevant in the local tissue damage associated with envenomations by Bothrops asper, a medically-important species in Central America and parts of South America. Six monoclonal antibodies (MoAb) against BaP1 (MABaP1) were produced and characterized regarding their isotype, dissociation constant (K(d)), specificity and ability to neutralize BaP1-induced hemorrhagic and proteolytic activity. Two MABaP1 are IgM, three are IgG1 and one is IgG2b. The K(d)s of IgG MoAbs were in the nM range. All IgG MoAbs recognized conformational epitopes of BaP1 and B. asper venom components but failed to recognize venoms from 27 species of Viperidae, Colubridae and Elapidae families. Clone 7 cross-reacted with three P-I SVMPs tested (moojeni protease, insularinase and neuwiedase). BaP1-induced hemorrhage was totally neutralized by clones 3, 6 and 8 but not by clone 7. Inhibition of BaP1 enzymatic activity on a synthetic substrate by MABaP1 was totally achieved by clones 3 and 6, and partially by clone 8, but not by clone 7. In conclusion, these neutralizing MoAbs against BaP1 may become important tools to understand structure-function relationships of BaP1 and the role of P-I class SVMP in snakebite envenomation. PMID:20674587

  20. Cytotoxicity induced in myotubes by a Lys49 phospholipase A2 homologue from the venom of the snake Bothrops asper: evidence of rapid plasma membrane damage and a dual role for extracellular calcium.

    PubMed

    Villalobos, Juan Carlos; Mora, Rodrigo; Lomonte, Bruno; Gutiérrez, José María; Angulo, Yamileth

    2007-12-01

    Acute muscle tissue damage, myonecrosis, is a typical consequence of envenomations by snakes of the family Viperidae. Catalytically-inactive Lys49 phospholipase A(2) homologues are abundant myotoxic components in viperid venoms, causing plasma membrane damage by a mechanism independent of phospholipid hydrolysis. However, the precise mode of action of these myotoxins remains unsolved. In this work, a cell culture model of C2C12 myotubes was used to assess the action of Bothrops asper myotoxin II (Mt-II), a Lys49 phospholipase A(2) homologue. Mt-II induced a dose- and time-dependent cytotoxic effect associated with plasma membrane disruption, evidenced by the release of the cytosolic enzyme lactate dehydrogenase and the penetration of propidium iodide. A rapid increment in cytosolic Ca(2+) occurred after addition of Mt-II. Such elevation was associated with hypercontraction of myotubes and blebbing of plasma membrane. An increment in the Ca(2+) signal was observed in myotube nuclei. Elimination of extracellular Ca(2+) resulted in increased cytotoxicity upon incubation with Mt-II, suggesting a membrane-protective role for extracellular Ca(2+). Chelation of cytosolic Ca(2+) with BAPTA-AM did not modify the cytotoxic effect, probably due to the large increment induced by Mt-II in cytosolic Ca(2+) which overrides the chelating capacity of BAPTA-AM. It is concluded that Mt-II induces rapid and drastic plasma membrane lesion and a prominent Ca(2+) influx in myotubes. Extracellular Ca(2+) plays a dual role in this model: it protects the membrane from the cytolytic action of the toxin; at the same time, the Ca(2+) influx that occurs after membrane disruption is likely to play a key role in the intracellular degenerative events associated with Mt-II-induced myotube damage. PMID:17560765

  1. Molecular evolution of vertebrate neurotrophins: co-option of the highly conserved nerve growth factor gene into the advanced snake venom arsenalf.

    PubMed

    Sunagar, Kartik; Fry, Bryan Grieg; Jackson, Timothy N W; Casewell, Nicholas R; Undheim, Eivind A B; Vidal, Nicolas; Ali, Syed A; King, Glenn F; Vasudevan, Karthikeyan; Vasconcelos, Vitor; Antunes, Agostinho

    2013-01-01

    Neurotrophins are a diverse class of structurally related proteins, essential for neuronal development, survival, plasticity and regeneration. They are characterized by major family members, such as the nerve growth factors (NGF), brain-derived neurotrophic factors (BDNF) and neurotrophin-3 (NT-3), which have been demonstrated here to lack coding sequence variations and follow the regime of negative selection, highlighting their extremely important conserved role in vertebrate homeostasis. However, in stark contrast, venom NGF secreted as part of the chemical arsenal of the venomous advanced snake family Elapidae (and to a lesser extent Viperidae) have characteristics consistent with the typical accelerated molecular evolution of venom components. This includes a rapid rate of diversification under the significant influence of positive-selection, with the majority of positively-selected sites found in the secreted ?-polypeptide chain (74%) and on the molecular surface of the protein (92%), while the core structural and functional residues remain highly constrained. Such focal mutagenesis generates active residues on the toxin molecular surface, which are capable of interacting with novel biological targets in prey to induce a myriad of pharmacological effects. We propose that caenophidian NGFs could participate in prey-envenoming by causing a massive release of chemical mediators from mast cells to mount inflammatory reactions and increase vascular permeability, thereby aiding the spread of other toxins and/or by acting as proapoptotic factors. Despite their presence in reptilian venom having been known for over 60 years, this is the first evidence that venom-secreted NGF follows the molecular evolutionary pattern of other venom components, and thus likely participates in prey-envenomation. PMID:24312363

  2. Biochemical characterization of a factor X activator protein purified from Walterinnesia aegyptia venom.

    PubMed

    Khan, Sami U; Al-Saleh, Saad S

    2015-10-01

    Factor X of blood coagulation cascade can be activated by both intrinsic and extrinsic activating complex, trypsin and some kind of snake venom. A factor X activator protein is reported in Elapidae snake venom. The aim of this study was to evaluate biochemical properties of factor X activator protein because of its prospective application in biochemical research and therapeutics. Crude venom was fractionated on a HPLC system Gold 126/1667 using a combination of Protein PAK 125 and Protein PAK 60 Columns. Molecular weight was determined using SDS-PAGE. Walterinnesia aegyptia venom was fractionated into several protein peaks, but procoagulant and factor X activation activity coexisted into peak no.6. It appeared as single band on native PAGE and molecular weight was 60,000 ± 3. Purified up to 37-fold over crude venom. It shortened recalcification time, effect was dose-dependent and strictly Ca(2++)-dependent. Factor X activator seems to be able to activate factor X specifically because it showed no activation activity on human prothrombin, plasminogen, or protein C. It did not hydrolyze factor Xa substrate S-2222, thrombin substrate S-2238, plasmin substrate S-2251 or S-2302 and kalikrein substrate S-2266. It did not hydrolyze synthetic ester benzoyl arginine ethyl ester. Procoagulant activity was completely inhibited by irreversible serine protease inhibitors phenylmethylsulphonyl fluoride and N-p-tosylphenylalanine chloromethyl ketone. This study illustrates that factor X activator from W. aegyptia is though different in many aspects from factor X activators of Viperidae and Crotalidae venoms, but shows several properties identical to factor X activators from Elapidae venoms. PMID:26407136

  3. Evaluation of cytotoxic activities of snake venoms toward breast (MCF-7) and skin cancer (A-375) cell lines.

    PubMed

    Bradshaw, Michael J; Saviola, Anthony J; Fesler, Elizabeth; Mackessy, Stephen P

    2014-11-19

    Snake venoms are mixtures of bioactive proteins and peptides that exhibit diverse biochemical activities. This wide array of pharmacologies associated with snake venoms has made them attractive sources for research into potentially novel therapeutics, and several venom-derived drugs are now in use. In the current study we performed a broad screen of a variety of venoms (61 taxa) from the major venomous snake families (Viperidae, Elapidae and "Colubridae") in order to examine cytotoxic effects toward MCF-7 breast cancer cells and A-375 melanoma cells. MTT cell viability assays of cancer cells incubated with crude venoms revealed that most venoms showed significant cytotoxicity. We further investigated venom from the Red-bellied Blacksnake (Pseudechis porphyriacus); venom was fractionated by ion exchange fast protein liquid chromatography and several cytotoxic components were isolated. SDS-PAGE and MALDI-TOF mass spectrometry were used to identify the compounds in this venom responsible for the cytotoxic effects. In general, viper venoms were potently cytotoxic, with MCF-7 cells showing greater sensitivity, while elapid and colubrid venoms were much less toxic; notable exceptions included the elapid genera Micrurus, Naja and Pseudechis, which were quite cytotoxic to both cell lines. However, venoms with the most potent cytotoxicity were often not those with low mouse LD50s, including some dangerously venomous viperids and Australian elapids. This study confirmed that many venoms contain cytotoxic compounds, including catalytic PLA2s, and several venoms also showed significant differential toxicity toward the two cancer cell lines. Our results indicate that several previously uncharacterized venoms could contain promising lead compounds for drug development. PMID:25407733

  4. Molecular Evolution of Vertebrate Neurotrophins: Co-Option of the Highly Conserved Nerve Growth Factor Gene into the Advanced Snake Venom Arsenalf

    PubMed Central

    Sunagar, Kartik; Fry, Bryan Grieg; Jackson, Timothy N. W.; Casewell, Nicholas R.; Undheim, Eivind A. B.; Vidal, Nicolas; Ali, Syed A.; King, Glenn F.; Vasudevan, Karthikeyan; Vasconcelos, Vitor; Antunes, Agostinho

    2013-01-01

    Neurotrophins are a diverse class of structurally related proteins, essential for neuronal development, survival, plasticity and regeneration. They are characterized by major family members, such as the nerve growth factors (NGF), brain-derived neurotrophic factors (BDNF) and neurotrophin-3 (NT-3), which have been demonstrated here to lack coding sequence variations and follow the regime of negative selection, highlighting their extremely important conserved role in vertebrate homeostasis. However, in stark contrast, venom NGF secreted as part of the chemical arsenal of the venomous advanced snake family Elapidae (and to a lesser extent Viperidae) have characteristics consistent with the typical accelerated molecular evolution of venom components. This includes a rapid rate of diversification under the significant influence of positive-selection, with the majority of positively-selected sites found in the secreted β-polypeptide chain (74%) and on the molecular surface of the protein (92%), while the core structural and functional residues remain highly constrained. Such focal mutagenesis generates active residues on the toxin molecular surface, which are capable of interacting with novel biological targets in prey to induce a myriad of pharmacological effects. We propose that caenophidian NGFs could participate in prey-envenoming by causing a massive release of chemical mediators from mast cells to mount inflammatory reactions and increase vascular permeability, thereby aiding the spread of other toxins and/or by acting as proapoptotic factors. Despite their presence in reptilian venom having been known for over 60 years, this is the first evidence that venom-secreted NGF follows the molecular evolutionary pattern of other venom components, and thus likely participates in prey-envenomation. PMID:24312363

  5. Evaluation of the lethal potency of scorpion and snake venoms and comparison between intraperitoneal and intravenous injection routes.

    PubMed

    Oukkache, Naoual; El Jaoudi, Rachid; Ghalim, Noreddine; Chgoury, Fatima; Bouhaouala, Balkiss; Mdaghri, Naima El; Sabatier, Jean-Marc

    2014-06-01

    Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD??) of scorpion and snake venoms appears to be an important step to assess (and compare) venom toxic activity. Such LD?? values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD?? values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP) versus intravenous (IV)). The analysis of experimental LD?? values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am) is intrinsically more toxic than Androctonus australis hector (Aah) species, whereas the latter is more toxic than Buthus occitanus (Bo). Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc) is more toxic than either Bitis arietans (Ba) or Macrovipera lebetina (Ml) species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh) is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the nature of toxins, might be attributed to the rich composition of high molecular weight enzymes in the case of viper venoms. PMID:24926799

  6. Structural and Functional Studies of a Bothropic Myotoxin Complexed to Rosmarinic Acid: New Insights into Lys49-PLA2 Inhibition

    PubMed Central

    dos Santos, Juliana I.; Cardoso, Fábio F.; Soares, Andreimar M.; dal Pai Silva, Maeli; Gallacci, Márcia; Fontes, Marcos R. M.

    2011-01-01

    Snakebite envenoming is an important public health problem in many tropical and subtropical countries, and is considered a neglected tropical disease by the World Health Organization. Most severe cases are inflicted by species of the families Elapidae and Viperidae, and lead to a number of systemic and local effects in the victim. One of the main problems regarding viperidic accidents is prominent local tissue damage whose pathogenesis is complex and involves the combined actions of a variety of venom components. Phospholipases A2 (PLA2s) are the most abundant muscle-damaging components of these venoms. Herein, we report functional and structural studies of PrTX-I, a Lys49-PLA2 from Bothops pirajai snake venom, and the influence of rosmarinic acid (RA) upon this toxin's activities. RA is a known active component of some plant extracts and has been reported as presenting anti-myotoxic properties related to bothopic envenomation. The myotoxic activity of Lys49-PLA2s is well established in the literature and although no in vivo neurotoxicity has been observed among these toxins, in vitro neuromuscular blockade has been reported for some of these proteins. Our in vitro studies show that RA drastically reduces both the muscle damage and the neuromuscular blockade exerted by PrTX-I on mice neuromuscular preparations (by ?80% and ?90%, respectively). These results support the hypothesis that the two effects are closely related and lead us to suggest that they are consequences of the muscle membrane-destabilizing activity of the Lys49-PLA2. Although the C-terminal region of these proteins has been reported to comprise the myotoxic site, we demonstrate by X-ray crystallographic studies that RA interacts with PrTX-I in a different region. Consequently, a new mode of Lys49-PLA2 inhibition is proposed. Comparison of our results with others in the literature suggests possible new ways to inhibit bothropic snake venom myotoxins and improve serum therapy. PMID:22205953

  7. In vivo evaluation of homeostatic effects of Echis carinatus snake venom in Iran

    PubMed Central

    2013-01-01

    Background The venom of the family Viperidae, including the saw-scaled viper, is rich in serine proteinases and metalloproteinases, which affect the nervous system, complementary system, blood coagulation, platelet aggregation and blood pressure. One of the most prominent effects of the snake venom of Echis carinatus (Ec) is its coagulation activity, used for killing prey. Materials and methods Subfractions F1A and F1B were isolated from Ec crude venom by a combination of gel chromatography (Sephadex G-75) and ion exchange chromatography on a DEAE-Sepharose (DE-52). These subfractions were then intravenously (IV) injected into NIH male mice. Blood samples were taken before and after the administration of these subfractions. Times for prothrombin, partial thromboplastin and fibrinogen were recorded. Results and conclusions Comparison of the prothrombin time before and after F1A and F1B administrations showed that time for blood coagulation after injection is shorter than that of normal blood coagulation and also reduced coagulation time after Ec crude venom injection. This difference in coagulation time shows the intense coagulation activity of these subfractions that significantly increase the coagulation cascade rate and Causes to quick blood coagulation. The LD50 of the Ec crude venom was also determined to be 11.1 ?g/mouse. Different crude venom doses were prepared with physiological serum and injected into four mice. Comparison of the prothrombin times after injection of subfractions F1A and F1B showed that the rate of mouse blood coagulation increases considerably. Comparing the partial thromboplastin times after injecting these subfractions with this normal test time showed that the activity rate of intrinsic blood coagulation system rose sharply in mice. Finally, by comparing the fibrinogen time after subfraction injections and normal test time, we can infer intense activation of coagulation cascade and fibrin production. PMID:23848979

  8. Categorization of venoms according to bonding properties: An immunological overview.

    PubMed

    Ibrahim, Nihal M; El-Kady, Ebtsam M; Asker, Mohsen S

    2016-02-01

    In this report, we present a study on the antigenic cross-reactivity of various venoms from the most dangerous Egyptian snakes and scorpions belonging to families Elapidae, Viperidae and Buthidae. The study was carried out with special reference to bonding properties between venoms and antivenoms and their involvement in the formation of specific and/or cross-reactive interactions. The homologous polyclonal antivenoms showed high reactivity to the respective venoms and cross-reacted with varying degrees to other non-homologous venoms. Assorting the antivenoms according to their susceptibility to dissociation by different concentrations of NH4SCN revealed that most of the antibodies involved in homologous venom-antivenom interactions were highly avid; building up strong venom-antivenom bonding. Whereas cross-reactions due to heterologous interactions were mediated by less avid antibodies that ultimately led to the formation of venom-antivenom bonding of different power strengths depending on the antigenic similarity and hence on the phylogenetic relationship of the tested venom. A new parameter evaluating high and low avid interactions, designated as H/L value, for each antigen-antibody bonding was initiated and used as an indicator of bonding strength between different venom-antivenom partners. H/L values were many folds higher than 1 for homologous and closely related venoms, 1 or around 1 for cross-reactive venoms, whereas venoms from unrelated remote sources recorded H/L values far less than 1. Using well defined polyclonal antivenoms, H/L value was successfully used to assign eight unknown venoms to their animal families and the results were confirmed by species-specific ELISA and immunoblotting assays. PMID:26690707

  9. Isolation and characterization of two disintegrins inhibiting ADP-induced human platelet aggregation from the venom of Crotalus scutulatus scutulatus (Mohave Rattlesnake)

    SciTech Connect

    Sanchez, Elda E.; Galan, Jacob A.; Russell, William K.; Soto, Julio G.; Russell, David H.; Perez, John C. . E-mail: kfjcp00@tamuk.edu

    2006-04-01

    Disintegrins and disintegrin-like proteins are molecules found in the venom of four snake families (Atractaspididae, Elapidae, Viperidae, and Colubridae). The disintegrins are nonenzymatic proteins that inhibit cell-cell interactions, cell-matrix interactions, and signal transduction, and may have potential in the treatment of strokes, heart attacks, cancers, and osteoporosis. Prior to 1983, the venom of Crotalus scutulatus scutulatus (Mohave Rattlesnake) was known to be only neurotoxic; however, now there is evidence that these snakes can contain venom with: (1) neurotoxins; (2) hemorrhagins; and (3) both neurotoxins and hemorrhagins. In this study, two disintegrins, mojastin 1 and mojastin 2, from the venom of a Mohave rattlesnake collected in central Arizona (Pinal County), were isolated and characterized. The disintegrins in these venoms were identified by mass-analyzed laser desorption ionization/time-of-flight/time-of-flight (MALDI/TOF/TOF) mass spectrometry as having masses of 7.436 and 7.636 kDa. Their amino acid sequences are similar to crotratroxin, a disintegrin isolated from the venom of the western diamondback rattlesnake (C. atrox). The amino acid sequence of mojastin 1 was identical to the amino acid sequence of a disintegrin isolated from the venom of the Timber rattlesnake (C. horridus). The disintegrins from the Mohave rattlesnake venom were able to inhibit ADP-induced platelet aggregation in whole human blood both having IC{sub 5}s of 13.8 nM, but were not effective in inhibiting the binding of human urinary bladder carcinoma cells (T24) to fibronectin.

  10. Oxygenation properties and isoform diversity of snake hemoglobins.

    PubMed

    Storz, Jay F; Natarajan, Chandrasekhar; Moriyama, Hideaki; Hoffmann, Federico G; Wang, Tobias; Fago, Angela; Malte, Hans; Overgaard, Johannes; Weber, Roy E

    2015-11-01

    Available data suggest that snake hemoglobins (Hbs) are characterized by a combination of unusual structural and functional properties relative to the Hbs of other amniote vertebrates, including oxygenation-linked tetramer-dimer dissociation. However, standardized comparative data are lacking for snake Hbs, and the Hb isoform composition of snake red blood cells has not been systematically characterized. Here we present the results of an integrated analysis of snake Hbs and the underlying α- and β-type globin genes to characterize 1) Hb isoform composition of definitive erythrocytes, and 2) the oxygenation properties of isolated isoforms as well as composite hemolysates. We used species from three families as subjects for experimental studies of Hb function: South American rattlesnake, Crotalus durissus (Viperidae); Indian python, Python molurus (Pythonidae); and yellow-bellied sea snake, Pelamis platura (Elapidae). We analyzed allosteric properties of snake Hbs in terms of the Monod-Wyman-Changeux model and Adair four-step thermodynamic model. Hbs from each of the three species exhibited high intrinsic O2 affinities, low cooperativities, small Bohr factors in the absence of phosphates, and high sensitivities to ATP. Oxygenation properties of the snake Hbs could be explained entirely by allosteric transitions in the quaternary structure of intact tetramers, suggesting that ligation-dependent dissociation of Hb tetramers into αβ-dimers is not a universal feature of snake Hbs. Surprisingly, the major Hb isoform of the South American rattlesnake is homologous to the minor HbD of other amniotes and, contrary to the pattern of Hb isoform differentiation in birds and turtles, exhibits a lower O2 affinity than the HbA isoform. PMID:26354849

  11. Marine electromagnetic experiment across the Nicaragua Trench: Imaging water-rich faults and melt-rich asthenosphere

    NASA Astrophysics Data System (ADS)

    Naif, Samer Nasri

    Electromagnetic (EM) methods have been widely applied in exploration geophysics and to study tectonics for several decades. Electrical resistivity, or its reciprocal conductivity, is a physical quantity that varies by several orders of magnitude. Bulk resistivity is highly dependent on the presence of fluids and ore bodies. While EM is primarily used to map the geoelectrical structures of terrestrial environments, advances over the last two decades in instrument technology and computing software have not only made marine EM experiments viable but also routine and reliable. In this dissertation, I explore the utility of the marine magnetotelluric and controlled-source electromagnetic techniques for probing subduction zone processes. In the Spring of 2010, the Scripps Institution of Oceanography Marine EM group ventured on the R/V Melville to conduct the Serpentinite, Extension and Regional Porosity Experiment across the Nicaragua Trench (SERPENT). Over the course of 28 days, 54 sites of broadband marine magnetotelluric (MT) and 800 km of marine controlled-source electromagnetic (CSEM) data were collected, culminating in the first CSEM survey and the largest marine EM dataset at a subduction zone to date. In this dissertation, I perform regularized two-dimensional inversions on the marine MT and CSEM data from SERPENT to model the electrical resistivity structure of the crust and upper mantle. The MT data revealed an unexpected conductive channel at a depth interval of 45-70 km. I apply measurements from laboratory studies and find that only partial melt can account for the electrical signature of the conductor. I conclude that the anomalous channel is a sheared partial melt layer at the lithosphere- asthenosphere boundary that decouples the lithosphere from the deeper mantle. The CSEM data image sub-vertical conductive channels that correlate with outer rise fault scarps, providing the first observation to confirm bending faults behave as fluid pathways. I use Archie's law to infer porosity and find that the crust subducts significantly more pore water than previously thought. The CSEM data also image the complete subduction of the incoming sediments along the megathrust plate interface, providing the first large-scale estimates of porosity at the megathrust. At 20 km into the forearc, a conductive anomaly extends from the plate interface into the overlying crust beneath a high concentration of active seafloor seeps, possibly imaging both the origin and migratory pathway of fluids escaping along the margin seafloor. The location of the anomaly correlates with a section of the seafloor that exhibits steepened bathymetric slope, suggesting a sediment underplating mechanism as its cause.

  12. Snake mitochondrial genomes: phylogenetic relationships and implications of extended taxon sampling for interpretations of mitogenomic evolution

    PubMed Central

    2010-01-01

    Background Snake mitochondrial genomes are of great interest in understanding mitogenomic evolution because of gene duplications and rearrangements and the fast evolutionary rate of their genes compared to other vertebrates. Mitochondrial gene sequences have also played an important role in attempts to resolve the contentious phylogenetic relationships of especially the early divergences among alethinophidian snakes. Two recent innovative studies found dramatic gene- and branch-specific relative acceleration in snake protein-coding gene evolution, particularly along internal branches leading to Serpentes and Alethinophidia. It has been hypothesized that some of these rate shifts are temporally (and possibly causally) associated with control region duplication and/or major changes in ecology and anatomy. Results The near-complete mitochondrial (mt) genomes of three henophidian snakes were sequenced: Anilius scytale, Rhinophis philippinus, and Charina trivirgata. All three genomes share a duplicated control region and translocated tRNALEU, derived features found in all alethinophidian snakes studied to date. The new sequence data were aligned with mt genome data for 21 other species of snakes and used in phylogenetic analyses. Phylogenetic results agreed with many other studies in recovering several robust clades, including Colubroidea, Caenophidia, and Cylindrophiidae+Uropeltidae. Nodes within Henophidia that have been difficult to resolve robustly in previous analyses remained uncompellingly resolved here. Comparisons of relative rates of evolution of rRNA vs. protein-coding genes were conducted by estimating branch lengths across the tree. Our expanded sampling revealed dramatic acceleration along the branch leading to Typhlopidae, particularly long rRNA terminal branches within Scolecophidia, and that most of the dramatic acceleration in protein-coding gene rate along Serpentes and Alethinophidia branches occurred before Anilius diverged from other alethinophidians. Conclusions Mitochondrial gene sequence data alone may not be able to robustly resolve basal divergences among alethinophidian snakes. Taxon sampling plays an important role in identifying mitogenomic evolutionary events within snakes, and in testing hypotheses explaining their origin. Dramatic rate shifts in mitogenomic evolution occur within Scolecophidia as well as Alethinophidia, thus falsifying the hypothesis that these shifts in snakes are associated exclusively with evolution of a non-burrowing lifestyle, macrostomatan feeding ecology and/or duplication of the control region, both restricted to alethinophidians among living snakes. PMID:20055998

  13. The complete mitochondrial genome of a gecko and the phylogeneticposition of the Middle Eastern teratoscincus keyserlingii

    SciTech Connect

    Macey, J. Robert; Fong, Jonathan J.; Kuehl, Jennifer V.; Shafiei,Soheila; Ananjeva, Natalia B.; Papenfuss, Theodore J.; Boore, Jeffrey L.

    2005-04-22

    Sqamate reptiles are traditionally divided into six groups: Iguania, Anguimorpha, Scincomorpha, Gekkota (these four are lizards), Serpentes (snakes), and Amphisbaenia (the so-called worm lizards). Currently there are complete mitochondrial genomes from two representatives of the Iguania (Janke et al., 2001; Kumazawa, 2004), three from the Anguimorpha (Kumazawa, 2004; Kumazawa and Endo, 2004), two from the Scincomorpha (Kumazawa and Nishida, 1999; Kumazawa, 2004), two from Serpentes (Kumazawa et al., 1998; Kumazawa, 2004) and 12 from Amphisbaenia (Macey et al., 2004). The only traditional group of Squamata from which a complete mitochondrial genome has not been sequenced is the Gekkota. Here we report the complete mitochondrial genome of Teratoscincus keyserlingii, a Middle Eastern representative of the Gekkota. The gekkonid lizard genus Teratoscincus is distributed throughout the deserts of central and southwest Asia as shown in figure 1, with five species currently recognized (Macey et al. 1997a, 1999b). Included in this figure are the positions of mountain ranges discussed in the text; see also figure 1 in Macey et al. (1999b). Two species, T. bedriagai and T. microlepis, are restricted to Southwest Asia south of the Kopet Dagh and Hindu Kush in Iran, Afghanistan, and Pakistan (Anderson, 1999). Two species are found in the deserts of western China and Mongolia, with T. przewalskii occurring in the Taklimakan and lowland Gobi deserts, and T. roborowskii restricted to the Turpan Depression. The fifth species, T. scincus, is sometimes considered to be restricted to the Caspian Basin in Kazakhstan, Kyrgyzistan, Tadjikistan, Turkmenistan and Uzbekistan. Alternatively, Teratoscincus populations in Southwest Asia, primarily on the Iranian Plateau, situated directly north of the Arabian Plate, are sometimes considered to be a subspecies of T. scincus or, otherwise, to constitute a sixth species, T. keyserlingii. Macey et al. (1999b) assessed the phylogenetic relationships of four Teratoscincus species with mitochondrial DNA sequences from a {approx}1800 base-pair segment spanning from nad1 to cox1. Phylogenetic analysis places T. microlepis in a basal position to a clade containing T. scincus, T. przewalskii and T. roborowskii, with the later two as sister taxa. This phylogenetic arrangement suggests that tectonic plate movements in Southwest Asia and western China due to the Indian and Arabian collisions caused speciation among Teratoscincus species. No molecular phylogenetic study has included the putative species T. keyserlingii.

  14. Changes in deep-water epibenthic megafaunal assemblages in relation to seabed slope on the Nigerian margin

    NASA Astrophysics Data System (ADS)

    Jones, Daniel O. B.; Mrabure, Charles O.; Gates, Andrew R.

    2013-08-01

    Local-scale habitat heterogeneity associated with changes in slope is a ubiquitous feature of bathyal continental margins. The response of deep-sea species to high habitat heterogeneity is poorly known and slope can be used as a proxy for many important ecological variables, such as current flow, sedimentation and substratum type. This study determines how slope angle effects megafaunal species density and diversity at the Usan field, offshore Nigeria, between 740 and 760 m depth. This deep-water area is increasingly exploited for hydrocarbons, yet lacking in baseline biological information. Replicated remotely operated vehicle video transect surveys were carried out using industry infrastructure (through the SERPENT Project) at a representative range of slopes (1°, 3°, 11° and 29°). Twenty-four species of benthic megafaunal invertebrate were found, numerically dominated by the echinoid Phormosoma placenta, and nine species of fish were observed. Megafaunal invertebrate deposit feeder density decreased significantly with increasing slope (density range 0.503-0.081 individuals m-2). Densities of megafaunal suspension feeders were very low except at the highest slope site (mean density 0.17 m-2). Overall species richness was greater on steeper slopes, although the richness of deposit feeders was not affected. Reduced labile organic matter in sediments on steeper slopes likely reduced deposit feeder densities, but increased current flow at higher slopes allowed both increased richness and density of suspension feeders.

  15. Origins of the ancient constellations: II. The Mediterranean traditions

    NASA Astrophysics Data System (ADS)

    Rogers, J. H.

    1998-04-01

    The classical map of the sky, with the 48 Greek constellations, was derived from at least two different pre-Greek traditions. One tradition comprised the 12 signs of the zodiac, with several associated animal constellations, all of which developed over ~3200-500 BC in Mesopotamia in a religious or ritual tradition. These were taken over by the Greeks around 500 BC. However the other Babylonian constellations, their farming-calendar tradition, were not adopted. The other tradition was not Mesopotamian; it comprised large constellations which appear to date from ~2800 BC, probably from the Mediterranean region, devised for the navigators of ships. They include huge bears and serpents which marked the celestial pole and equator at that time, and probably the four anonymous giants which we know as Hercules, Ophiuchus, Bootes, and Auriga, as well as some of the large southern 'marine' constellations. The origins of some other constellations, including the Perseus tableau and various animals, are unknown; they may have been new creations of the Greeks. The Greeks assembled the classical sky-map from these different sources between 540-370 BC, but many of the familiar legends were only applied to the constellations later.

  16. Genome-Wide Transcription Analysis of Clinal Genetic Variation in Drosophila

    PubMed Central

    Chen, Ying; Lee, Siu F.; Blanc, Eric; Reuter, Caroline; Wertheim, Bregje; Martinez-Diaz, Pedro; Hoffmann, Ary A.; Partridge, Linda

    2012-01-01

    Clinal variation in quantitative traits is widespread, but its genetic basis awaits identification. Drosophila melanogaster shows adaptive, clinal variation in traits such as body size along latitudinal gradients on multiple continents. To investigate genome wide transcription differentiation between North and South that might contribute to the clinal phenotypic variation, we compared RNA expression patterns during development of D. melanogaster from tropical northern and temperate southern populations using whole genome tiling arrays. We found that genes that were differentially expressed between the cline ends were generally associated with metabolism and growth, and experimental alteration of expression of a sample of them generally resulted in altered body size in the predicted direction, sometimes significantly so. We further identified the serpent (srp) transcription factor binding sites to be enriched near genes up-regulated in expression in the south. Analysis of clinal populations revealed a significant cline in the expression level of srp. Experimental over-expression of srp increased body size, as predicted from its clinal expression pattern, suggesting that it may be involved in regulating adaptive clinal variation in Drosophila. This study identified a handful of genes that contributed to clinal phenotypic variation through altered gene expression level, yet misexpression of individual gene led to modest body size change. PMID:22514645

  17. Histological analysis of spermatogenesis and the germ cell development strategy within the testis of the male Western Cottonmouth Snake, Agkistrodon piscivorus leucostoma.

    PubMed

    Gribbins, Kevin M; Rheubert, Justin L; Collier, Matthew H; Siegel, Dustin S; Sever, David M

    2008-11-20

    Cottonmouth (Agkistrodon piscivorus leucostoma) testes were examined histologically to determine the germ cell development strategy employed during spermatogenesis. Testicular tissues from Cottonmouths were collected monthly from swamps around Hammond, Louisiana. Pieces of testis were fixed in Trump's fixative, dehydrated in ethanol, embedded in Spurr's plastic, sectioned with an ultramicrotome, and stained with toluidine blue and basic fuchsin. Spermatogenesis within Cottonmouths occurs in two independent events within a single calendar year. The testes are active during the months of March-June and August-October with spermiation most heavily observed during April-May and October. To our knowledge, this is the first study that describes bimodal spermatogenesis occurring in the same year within the subfamily Crotalinae. During spermatogenesis, no consistent spatial relationships are observed between germ cell generations. Typically, either certain cell types were missing (spermatocytes) or the layering of 3-5 spermatids and/or spermatocytes within the same cross-section of seminiferous tubule prevented consistent spatial stages from occurring. This temporal pattern of sperm development is different from the spatial development found within birds and mammals, being more reminiscent of that seen in amphibians, and has now been documented within every major clade of reptile (Chelonia, Serpentes, Sauria, Crocodylia). This primitive-like sperm development, within a testis structurally similar to mammals and birds, may represent an intermediate testicular model within the basally positioned (phylogenetically) reptiles that may be evolutionarily significant. PMID:18926676

  18. Consecutive virgin births in the new world boid snake, the Colombian rainbow Boa, Epicrates maurus.

    PubMed

    Booth, Warren; Million, Larry; Reynolds, R Graham; Burghardt, Gordon M; Vargo, Edward L; Schal, Coby; Tzika, Athanasia C; Schuett, Gordon W

    2011-01-01

    Until recently, facultative automictic parthenogenesis within the squamate reptiles exhibiting ZZ:ZW genetic sex determination has resulted in single reproductive events producing male (ZZ) or female (ZW) offspring. With the recent discovery of viable parthenogenetically produced female (WW) Boa constrictors, the existence of further parthenogenetic events resulting in WW females was questioned. Here, we provide genetic evidence for consecutive virgin births by a female Colombian rainbow boa (Epicrates maurus), resulting in the production of WW females likely through terminal fusion automixis. Samples were screened at 22 microsatellite loci with 12 amplifying unambiguous products. Of these, maternal heterozygosity was observed in 4, with the offspring differentially homozygous at each locus. This study documents the first record of parthenogenesis within the genus Epicrates, a second within the serpent lineage Boidae, and the third genetically confirmed case of consecutive virgin births of viable offspring within any vertebrate lineage. Unlike the recent record in Boa constrictors, the female described here was isolated from conspecifics from birth, demonstrating that males are not required to stimulate parthenogenetic reproduction in this species and possibly other Boas. PMID:21868391

  19. The Right Scuff

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit acquired this image on the 72nd martian day, or sol, of its mission (March 15, 2004) with the left eye of its front hazard-identification camera after digging its wheel into the drift dubbed 'Serpent.' Creating the commands that would generate this scar was not an easy task for rover controllers. Essentially, they had to choreograph an intricate dance for Spirit, maneuvering it up the side of the dune, shimmying its left front wheel a number of times to create the scuff, and then reversing to attain proper positioning for miniature thermal emission spectrometer observations. Before the task was finished, Spirit moved forward to put the scuff within proper reach of the rover's arm.

    This scar allows the rover's instruments to see below the drift surface, to determine the composition of its materials. Initial results indicate that the drift material is similar to the basaltic sands that have been seen throughout Spirit's journey to the large crater dubbed 'Bonneville.' The material does not seem to be the same as that inside the crater.

    Two questions raised by these results are: Why is the dark sand in the crater not the same as the dark sand in the drift? And why are there two different dark soil-type deposits in such a small place?

  20. Large Cretaceous sphenodontian from Patagonia provides insight into lepidosaur evolution in Gondwana.

    PubMed

    Apesteguía, Sebastián; Novas, Fernando E

    2003-10-01

    Sphenodontian reptiles successfully radiated during Triassic and Jurassic times, but were driven almost to extinction during the Cretaceous period. The sparse Early Cretaceous record of sphenodontians has been interpreted as reflecting the decline of the group in favour of lizards, their suspected ecological successors. However, recent discoveries in Late Cretaceous beds in Patagonia partially modify this interpretation. Numerous skeletons of a new sphenodontian, Priosphenodon avelasi gen. et sp. nov., were collected from a single locality in the Cenomanian-Turonian Candeleros Formation, where it is more abundant than any other tetrapod group recorded in the quarry (for example, Crocodyliformes, Serpentes, Dinosauria and Mammalia). Adult specimens of Priosphenodon reached one metre in length, larger than any previously known terrestrial sphenodontian. Here we propose, using available evidence, that sphenodontians were not a minor component of the Cretaceous terrestrial ecosystems of South America, and that their ecological replacement by squamates was delayed until the early Tertiary. The new discovery helps to bridge the considerable gap in the fossil record (around 120 million years) that separates the Early Cretaceous sphenodontians from their living relatives (Sphenodon). PMID:14534584

  1. Mitochondrial introgression via ancient hybridization, and systematics of the Australian endemic pygopodid gecko genus Delma.

    PubMed

    Brennan, Ian G; Bauer, Aaron M; Jackman, Todd R

    2016-01-01

    Of the more than 1500 species of geckos found across six continents, few remain as unfamiliar as the pygopodids - Family Pygopodidae (Gray, 1845). These gekkotans are limited to Australia (44 species) and New Guinea (2 species), but have diverged extensively into the most ecologically diverse limbless radiation save Serpentes. Current phylogenetic understanding of the family has relied almost exclusively on two works, which have produced and synthesized an immense amount of morphological, geographical, and molecular data. However, current interspecific relationships within the largest genus Delma Gray 1831 are based chiefly upon data from two mitochondrial loci (16s, ND2). Here, we reevaluate the interspecific relationships within the genus Delma using two mitochondrial and four nuclear loci (RAG1, MXRA5, MOS, DYNLL1), and identify points of strong conflict between nuclear and mitochondrial genomic data. We address mito-nuclear discordance, and remedy this conflict by recognizing several points of mitochondrial introgression as the result of ancient hybridization events. Owing to the legacy value and intraspecific informativeness, we suggest the continued use of ND2 as a phylogenetic marker. Results identify strong support for species groups, but relationships among these clades, and the placement of several enigmatic taxa remain uncertain. We suggest a more careful review of Delma australis and the 'northwest Australia' clade. Accurately assessing and addressing species richness and relationships within this endemic Australian Gekkotan genus is relevant for understanding patterns of squamate speciation across the region. PMID:26505536

  2. Adaptive evolution of the venom-targeted vWF protein in opossums that eat pitvipers.

    PubMed

    Jansa, Sharon A; Voss, Robert S

    2011-01-01

    The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae) and pitvipers (Serpentes: Crotalinae). In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF), a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results, venomous snakes are prey, and their venom has a correspondingly defensive function in addition to its usual trophic role. PMID:21731638

  3. Carbon Isotope Systematics in Mineral-Catalyzed Hydrothermal Organic Synthesis Processes at High Temperature and Pressures

    NASA Technical Reports Server (NTRS)

    Fu, Qi; Socki, R. A.; Niles, Paul B.

    2011-01-01

    Observation of methane in the Martian atmosphere has been reported by different detection techniques. Reduction of CO2 and/or CO during serpentization by mineral surface catalyzed Fischer-Tropsch Type (FTT) synthesis may be one possible process responsible for methane generation on Mars. With the evidence a recent study has discovered for serpentinization in deeply buried carbon rich sediments, and more showing extensive water-rock interaction in Martian history, it seems likely that abiotic methane generation via serpentinization reactions may have been common on Mars. Experiments involving mineral-catalyzed hydrothermal organic synthesis processes were conducted at 750 C and 5.5 Kbars. Alkanes, alcohols and carboxylic acids were identified as organic compounds. No "isotopic reversal" of delta C-13 values was observed for alkanes or carboxylic acids, suggesting a different reaction pathway than polymerization. Alcohols were proposed as intermediaries formed on mineral surfaces at experimental conditions. Carbon isotope data were used in this study to unravel the reaction pathways of abiotic formation of organic compounds in hydrothermal systems at high temperatures and pressures. They are instrumental in constraining the origin and evolution history of organic compounds on Mars and other planets.

  4. Carbon Isotope Measurements of Experimentally-Derived Hydrothermal Mineral-Catalyzed Organic Products by Pyrolysis-Isotope Ratio Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Socki, Richard A.; Fu, Qi; Niles, Paul B.

    2011-01-01

    We report results of experiments to measure the C isotope composition of mineral catalyzed organic compounds derived from high temperature and high pressure synthesis. These experiments make use of an innovative pyrolysis technique designed to extract and measure C isotopes. To date, our experiments have focused on the pyrolysis and C isotope ratio measurements of low-molecular weight intermediary hydrocarbons (organic acids and alcohols) and serve as a proof of concept for making C and H isotope measurements on more complicated mixtures of solid-phase hydrocarbons and intermediary products produced during high temperature and high pressure synthesis on mineral-catalyzed surfaces. The impetus for this work stems from recently reported observations of methane detected within the Martian atmosphere [1-4], coupled with evidence showing extensive water-rock interaction during Martian history [5-7]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization reactions [8,9]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [10-12]. Further, recent experiments by Fu et al. [13] focus on examining detailed C isotope measurements of hydrocarbons produced by surface-catalyzed mineral reactions. Work described in this paper details the experimental techniques used to measure intermediary organic reaction products (alcohols and organic acids).

  5. Did Secret, Sacred Science: ``Kokopelli/Pamola,'' Motivate the Tarratines' Assassination of the Penobscots' Bashaba ca 1615, and Does ``Orono'' Yield Direct Physics Insights?

    NASA Astrophysics Data System (ADS)

    Ataide, Italani; de Souza, Beatriz; Pawa Matagamon, Sagamo

    2007-04-01

    ``Tarratine'' may share cognate phonetics with Tatoosh, (Makah, Pacific NE), Tuitan, Totonac, (coastal ``neighbors'' of the Aztec), Teedyuscung/Tatiuskundt, (Penn.), Teotihuacan, Tomtomhegan, (``ME'' ca 1781-2), Titikaka/Titicaca, and Tantaquidgeon, (Conn.); the military action that led to the assassination of the Penobscots' Bashaba has explanatory roots tying it to the last raid involving `Indian' military action of the Revolutionary War. ``Turf'' rights influenced conflict imperatives. Preserved linguistic roots have it best: Ñari Huallac, coupled with Arizona, Allagash, Allahpatah, and Orono/Orinoco, indicate traditionalists' information, by recognizing Kokopelli/Pamola/Pele/electromagnetics/EMF, says how nature behaves. Penobscots and modern Peruvian descendants of the Incas have it right: the concealed ``Serpent God'' of their EMF alter ego(s), says their science, (applied physics) is sacred because it ``predicts'' nature, even tinnitus, via ``Rawandagon''! To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.8

  6. Maine's MOLLOCKET and METALLAK: Adherents of God's Secret Spirit Signal, SSS, Applied Physicists of the EMF/Manitou, Doctors, Reincarnationists, "Potlachers," Confidants of the Powerful, and, they Did Own the Land.

    NASA Astrophysics Data System (ADS)

    Andrade, Jennifer; Ferreira, Nadja; Mc Leod, Roger D.

    2007-04-01

    Northeastern ``Indians,'' reputed to ``make the weather,'' actually, from youth, observed earth phenomena, including SSS. These are subtle and barely detectable visual artifacts of the electromagnetic field, special information that led/leads to their spiritual belief in reincarnation, which came from the EMF/SSS communication, backward and forward, (up to) seven generations. It commands communal, democratic, ``potlatch'' redistribution of accumulated wealth, Mother Earth's bounty, from their land, gifted by ``The Great Spirit,'' Manitou, Peru's Ñari Huallac, ``Serpent God.'' Genetics established the non-Asian origins of 1/3 of North American Indians. Linguistics indicates a major impact westwards to us. MILLInocket is ``Adherent of God (Spirit-signal) monk Cathar.'' Katahdin, with a shared root, has Manitou. After 1820, Gov. E. Lincoln and at least one US senator went westward to MetALLAk; his biography is by a Rumford, ME Knight of Pythias. Why? MOLLOCKET frequently asserted ownership of western Maine. ``Great Council Fires,'' religious ``Law Things,'' were at Merrymeeting Bay in pre-Colonial times. ``Medicine men/priests'' often participated as their applied scientist-statesmen. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.1

  7. Long-range RNA pairings contribute to mutually exclusive splicing.

    PubMed

    Yue, Yuan; Yang, Yun; Dai, Lanzhi; Cao, Guozheng; Chen, Ran; Hong, Weiling; Liu, Baoping; Shi, Yang; Meng, Yijun; Shi, Feng; Xiao, Mu; Jin, Yongfeng

    2016-01-01

    Mutually exclusive splicing is an important means of increasing the protein repertoire, by which the Down's syndrome cell adhesion molecule (Dscam) gene potentially generates 38,016 different isoforms in Drosophila melanogaster. However, the regulatory mechanisms remain obscure due to the complexity of the Dscam exon cluster. Here, we reveal a molecular model for the regulation of the mutually exclusive splicing of the serpent pre-mRNA based on competition between upstream and downstream RNA pairings. Such dual RNA pairings confer fine tuning of the inclusion of alternative exons. Moreover, we demonstrate that the splicing outcome of alternative exons is mediated in relative pairing strength-correlated mode. Combined comparative genomics analysis and experimental evidence revealed similar bidirectional structural architectures in exon clusters 4 and 9 of the Dscam gene. Our findings provide a novel mechanistic framework for the regulation of mutually exclusive splicing and may offer potentially applicable insights into long-range RNA-RNA interactions in gene regulatory networks. PMID:26554032

  8. The phylogenetic position and taxonomic status of the Rainbow Tree Snake Gonyophis margaritatus (Peters, 1871) (Squamata: Colubridae) .

    PubMed

    Chen, Xin; Mckelvy, Alexander D; Grismer, L Lee; Matsui, Masafumi; Nishikawa, Kanto; Burbrink, Frank T

    2014-01-01

    Molecular phylogenies have provided strong evidence for clarifying the taxonomy of groups with ambiguous morphological traits, thus avoiding potentially misleading conclusions based on evolutionary convergence of these traits. For snakes, established molecular databases along with new sequences from rare species allows us to estimate phylogenies, to clarify the phylogenetic relationships and test the monophyly of most taxonomic groups. Using one mitochondrial gene and five nuclear loci, we evaluate the taxonomic status of a rare Southeast Asian serpent, the Rainbow Tree Snake Gonyophis margaritatus (Squamata: Colubridae) by inferring a molecular phylogeny of 101 snake species. Both maximum likelihood and time- calibrated Bayesian inference phylogenies demonstrate that G. margaritatus is sister to Rhadinophis prasinus, previously considered to be part of a radiation of Old World ratsnakes. This group is in turn sister to a group containing Rhadinophis frenatus and Rhynchophis boulengeri with the entire clade originating in the mid-Miocene (~16 Ma) in Southeast Asia. This group is sister to the genus Gonyosoma and together originated in the early Miocene (~20 Ma). We discuss three potential solutions towards eliminating polyphyly of the genus Rhadinophis, but recommend using the genus name Gonyosoma for all species within this clade, which currently contains all of the species within the genera Gonyosoma, Gonyophis, Rhadinophis, and Rhynchophis.  PMID:25543651

  9. Spirit Digs In

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Mars Exploration Rover Spirit acquired this navigation camera image on the 72nd martian day, or sol, of its mission (March 15, 2004), after digging its wheel into the drift dubbed 'Serpent.' Creating the commands that would generate this 'scar' was not an easy task for rover controllers. Essentially, they had to choreograph an intricate dance for Spirit, maneuvering it up the side of the dune, shimmying its left front wheel a number of times to create the scuff, and then reversing to attain proper positioning for miniature thermal emission spectrometer observations. Before the task was finished, Spirit moved forward to put the scuff within proper reach of the rover's arm.

    This scar allows the rover's instruments to see below the drift surface, to determine the composition of the materials. Initial results indicate that the drift material is similar to the basaltic sands that have been seen throughout Spirit's journey to the large crater dubbed 'Bonneville.' The material does not seem to be the same as that inside the crater.

    Scientists are now looking to answer two questions: Why is the dark sand in the crater not the same as the dark sand in the drift? And why are there two different dark soil-type deposits in such a small place?

  10. Emergence and loss of magnetic flux on the solar surface

    NASA Astrophysics Data System (ADS)

    van Driel-Gesztelyi, Lidia

    2002-10-01

    This review is focused on observations and theoretical advances on large-scale flux emergence and decay, which forms and dominates the magnetic field patterns on the Sun. The basic characteristics of emerging flux (asymmetry, inclination to the vertical, twist, sea-serpent-like appearance in the early stage of flux emergence in the photosphere) are described together with the results of relevant MHD simulations, which help us to interpret these observations. Magnetic flux emergence is far from being a random process in the active belt: it has a grouping (nesting) tendency, which has important implications for the operation of the solar dynamo. As soon as active regions are fully formed, they start decaying. Their magnetic flux gradually speads over an ever-increasing area and gets removed from the photosphere via small scale processes (e.g. Ohmic dissipation and flux cancellation, including flux submergence). Emergence of U-loops may play an important role in the removal of large-scale flux from the photopshere.

  11. Did Indians of the Americas Preserve Linguistic Place-names Like Willimantic, CT, Indicating Some Islamic Interactions and Applied Physics Use, Before Columbus?

    NASA Astrophysics Data System (ADS)

    Crory, Erica; Mc Leod, Roger D.

    2007-10-01

    Modern Peruvians document: ``Ñari Huallac is the name of the town in the north of Peru (Piura) where our families come from. The words Ñari Huallac mean Serpent God, [editorial emphasis by underlining script is added], and are some of the few words which remain from the ancient Tallan civilization.'' Tallan seems related to The God, Allah, of Islam, as are Alaska, Allagash, Illinois, Willimantic, CT, and, in Maine, Metallak, Mollocket and Millinocket, Allahpatah, of Florida, and Allegheny of Pennsylvania. With this significance lies the partially concealed evidence that all three monotheistic faiths, during the times indicated by the language, understood there was a fundamental connection between The God, and what we would call today the electromagnetic field, EMF, of Mother Earth. Metallak: Doctor (at) The God (Spirit-signal, EMF), an ecclesiastical title, like Willimantic, The God Spirit-signal (where there is a) doctor. Alaska: The God Jesus Christ Spirit-signal (EMF). Millinocket: Adherent of The God monk Cathar, provides a reference date of about 1250 A.D. Illinois: The God Spirit-signal (EMF-detecting) monk. Mollocket asserted ownership of western Maine, until 1816. What did she know of importance from her war-hostage days in Boston?

  12. Preparation of nuclear libraries with deterministic and stochastic methods for LWR reflectors

    SciTech Connect

    Canepa, S.; Hursin, M.; Ferroukhi, H.; Pautz, A.

    2013-07-01

    The explicit reflector methodology is used in the system of codes CASMO-5 / SIMULATE-3 to include the reflector around the active core into the computational region and avoid adopting any ad-hoc or experimental albedo coefficients as boundary conditions. However, to complete the core calculation, a set of cross sections and discontinuity factors is needed for the reflector nodes and the accuracy of these nuclear parameters influences the final results, in particular along the peripheral regions of the core. In this paper the explicit reflector methodology of CASMO-5 is adopted to evaluate the few-group cross sections and discontinuity factors of the different reflector cases, based on the design of Generation II and III LWR reactors. In addition, in the perspective of using Monte-Carlo codes as a complementary option for lattice calculations of reflector configurations, the stochastic SERPENT code is also included as part of this benchmark. With the latter, the impact of applying 2-D reflector models with homogenized materials instead of explicit representation of the real geometrical structures is moreover evaluated and shown to be limited. (authors)

  13. Adaptive Evolution of the Venom-Targeted vWF Protein in Opossums that Eat Pitvipers

    PubMed Central

    Jansa, Sharon A.; Voss, Robert S.

    2011-01-01

    The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae) and pitvipers (Serpentes: Crotalinae). In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF), a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results, venomous snakes are prey, and their venom has a correspondingly defensive function in addition to its usual trophic role. PMID:21731638

  14. Neutronics and Fuel Performance Evaluation of Accident Tolerant Fuel under Normal Operation Conditions

    SciTech Connect

    Xu Wu; Piyush Sabharwall; Jason Hales

    2014-07-01

    This report details the analysis of neutronics and fuel performance analysis for enhanced accident tolerance fuel, with Monte Carlo reactor physics code Serpent and INL’s fuel performance code BISON, respectively. The purpose is to evaluate two of the most promising candidate materials, FeCrAl and Silicon Carbide (SiC), as the fuel cladding under normal operating conditions. Substantial neutron penalty is identified when FeCrAl is used as monolithic cladding for current oxide fuel. From the reactor physics standpoint, application of the FeCrAl alloy as coating layer on surface of zircaloy cladding is possible without increasing fuel enrichment. Meanwhile, SiC brings extra reactivity and the neutron penalty is of no concern. Application of either FeCrAl or SiC could be favorable from the fuel performance standpoint. Detailed comparison between monolithic cladding and hybrid cladding (cladding + coating) is discussed. Hybrid cladding is more practical based on the economics evaluation during the transition from current UO2/zircaloy to Accident Tolerant Fuel (ATF) system. However, a few issues remain to be resolved, such as the creep behavior of FeCrAl, coating spallation, inter diffusion with zirconium, etc. For SiC, its high thermal conductivity, excellent creep resistance, low thermal neutron absorption cross section, irradiation stability (minimal swelling) make it an excellent candidate materials for future nuclear fuel/cladding system.

  15. Comets in Indian Scriptures

    NASA Astrophysics Data System (ADS)

    Das Gupta, P.

    2016-01-01

    The Indo-Aryans of ancient India observed stars and constellations for ascertaining auspicious times in order to conduct sacrificial rites ordained by the Vedas. Naturally, they would have sighted comets and referred to them in the Vedic texts. In Rigveda (circa 1700–1500 BC) and Atharvaveda (circa 1150 BC), there are references to dhumaketus and ketus, which stand for comets in Sanskrit. Rigveda speaks of a fig tree whose aerial roots spread out in the sky (Parpola 2010). Had this imagery been inspired by the resemblance of a comet's tail with long and linear roots of a banyan tree (ficus benghalensis)? Varahamihira (AD 550) and Ballal Sena (circa AD 1100–1200) described a large number of comets recorded by ancient seers, such as Parashara, Vriddha Garga, Narada, and Garga, to name a few. In this article, we propose that an episode in Mahabharata in which a radiant king, Nahusha, who rules the heavens and later turns into a serpent after he kicked the seer Agastya (also the star Canopus), is a mythological retelling of a cometary event.

  16. Thermoplastic microchannel fabrication using carbon dioxide laser ablation.

    PubMed

    Wang, Shau-Chun; Lee, Chia-Yu; Chen, Hsiao-Ping

    2006-04-14

    We report the procedures of machining microchannels on Vivak co-polyester thermoplastic substrates using a simple industrial CO(2) laser marker. To avoid overheating the substrates, we develop low-power marking techniques in nearly anaerobic environment. These procedures are able to machine microchannels at various aspect ratios. Either straight or serpent channel can be easily marked. Like the wire-embossed channel walls, the ablated channel surfaces become charged after alkaline hydrolysis treatment. Stable electroosmotic flow in the charged conduit is observed to be of the same order of magnitude as that in fused silica capillary. Typical dynamic coating protocols to alter the conduit surface properties are transferable to the ablated channels. The effects of buffer acidity on electroosmotic mobility in both bare and coated channels are similar to those in fused silica capillaries. Using video microscopy we also demonstrate that this device is useful in distinguishing the electrophoretic mobility of bare and latex particles from that of functionalized ones. PMID:16288768

  17. [A traditional African treatment against sterility].

    PubMed

    Didillon, H; Tulu Kia Pansu, B

    1980-05-01

    A traditional ceremony used by the Yaka in Africa to treat sterility in women is described. Sterility is considered by Africans to be serious, since bearing children is seen as the only way that deceased ancestors can rejoin the living. Rites of purification are performed to reunite the sterile woman with the community. The first stage is a public confession, where the details of the couple's sexual life are told publicly. After this, a purification ritual takes place in the river to please the water spirits, after which the couple must change their names. After this, the clitoris of the woman is wounded by traditional midwives; this is called "cutting off the serpent's head". This is followed by other rituals, among them the throwing of a fish onto the fire by the sterile woman, symbolizing the unification of fire and water. This entire process is seen as a rite of passage which includes a sort of death and rebirth of the individual. PMID:12262311

  18. The life and viper of Dr Patrick Russell MD FRS (1727-1805): physician and naturalist.

    PubMed

    Hawgood, B J

    1994-11-01

    It is nearly two hundred years since the publication in 1796 of An Account of Indian Serpents collected on the Coast of Coromandel by Patrick Russell. Within the folio is a drawing and description of the venomous snake called Katuka Rekula Poda in the local Telugu language, whose venom was shown experimentally by Dr Russell to be nearly as lethal as that of Cobra de Capello. The snake is now known as Vipera russelli or Russell's viper. Dr Russell was representative of the naturalistic tendency of British medicine in the late 18th century. He was a keen observer and skilled doctor in clinical practice, particularly in Aleppo, Syria, during an outbreak of the plague, and indefatigable in his study of plant and animal life both in Aleppo and later in the Madras Province of India. As a physician as well as Naturalist to the East India Company in the Carnatic he was concerned with the problem of snakebite. His first aim was to find a means whereby the non-specialist could distinguish between poisonous and harmless snakes and so combat the terrible notion that all bites were mortal. His writing, encompassing social and natural histories and climaxed by a study of snakes, has left a rich legacy. Dr Patrick Russell was a man of the highest integrity and ability, a physician and naturalist par excellence. PMID:7886689

  19. EVOLUTION. A four-legged snake from the Early Cretaceous of Gondwana.

    PubMed

    Martill, David M; Tischlinger, Helmut; Longrich, Nicholas R

    2015-07-24

    Snakes are a remarkably diverse and successful group today, but their evolutionary origins are obscure. The discovery of snakes with two legs has shed light on the transition from lizards to snakes, but no snake has been described with four limbs, and the ecology of early snakes is poorly known. We describe a four-limbed snake from the Early Cretaceous (Aptian) Crato Formation of Brazil. The snake has a serpentiform body plan with an elongate trunk, short tail, and large ventral scales suggesting characteristic serpentine locomotion, yet retains small prehensile limbs. Skull and body proportions as well as reduced neural spines indicate fossorial adaptation, suggesting that snakes evolved from burrowing rather than marine ancestors. Hooked teeth, an intramandibular joint, a flexible spine capable of constricting prey, and the presence of vertebrate remains in the guts indicate that this species preyed on vertebrates and that snakes made the transition to carnivory early in their history. The structure of the limbs suggests that they were adapted for grasping, either to seize prey or as claspers during mating. Together with a diverse fauna of basal snakes from the Cretaceous of South America, Africa, and India, this snake suggests that crown Serpentes originated in Gondwana. PMID:26206932

  20. Art exhibit focuses on African astronomy

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2012-07-01

    Connections between Africans and astronomy are the focus of a new exhibition in the National Museum of African Art in Washington, D. C. "African Cosmos: Stellar Arts," which includes artwork, cultural items, and scientific displays from ancient to contemporary times, is the first major exhibit "that brings together arts and science focused on Africa's contribution to keen observations of the heavens over time," curator Christine Mullen Kreamer said at a 20 June news briefing. Among the exhibit's nearly 100 objects are an ancient Egyptian mummy board that includes a representation of the sky goddess Nut, sculptures by the Dogon people of Mali depicting figures in relation to the cosmos, a video that uses data from two square degrees of the Hubble Space Telescope Cosmic Evolution Survey, and a nearly floor-to-ceiling "Rainbow Serpent" constructed of plastic containers by Benin artist Hazoume. An untitled acrylic painting (Figure 1) by South African Gavin Jantjes evokes a myth of the Khoi San people of southern Africa, as it portrays a girl throwing evening fire embers into the night sky, where they remained as the Milky Way.

  1. Development and evolution of an Alpine sulphuric acid cave: Kraushoehle (Austria)

    NASA Astrophysics Data System (ADS)

    de Waele, J.; Plan, L.; Audra, Ph.; Rossi, A.; Spötl, Ch.; Polyak, V.; McIntosh, W.

    2009-04-01

    The number of known active and fossil hypogene cave systems is increasing rapidly thanks to recent advances in our understanding of this type of karst. Many cave systems previously thought to be of epigene origin have undergone more or less important phases of hypogene development. Epigene overprinting tends to obliterate hypogene features rendering identification of caves of multiphase speleogenesis a challenge. Among hypogene caves the sulphuric acid ones are the most interesting for a number of reasons: they host important bacterial and arthropod communities, they have peculiar and typical morphologies, and contain a variety of mineralisations. Sulphuric acid caves have been described from the Americas (Lechuguilla and Carlsbad in New Mexico, Cueva de Villa Luz in Mexico, Kane caves in Wyoming), but examples are also known in Europe (Movile cave in Romania, Frasassi and Monte Cucco in Italy). Until recently, the Serpents cave (Aix-les-Bains, northern Prealps) was the only sulphuric acid cave described in the international literature from the Alpine belt. Kraush

  2. Do Cross-circle Designs, the Mayan World Tree, Chitto Tustenuggee's, and Miami's Tequesta, Sites have Analogs in Brazil as they have in Peru, Europe, and Africa?

    NASA Astrophysics Data System (ADS)

    Ataide, Jade; Mc Leod, Roger; Mc Leod, David

    2007-04-01

    Florida's Miami Tequesta site conveys information about potential tornadoes, hurricanes, and even earthquakes. It is visually analogous to cross-circle designs, like other equivalent sites we have located, as in Maine, New Hampshire, in Medicine Wheels, and elsewhere. We focus on the detectable effects of time-and-place dependent electromagnetic signals. Non-technologic societies, and individuals, still find and use them, even today, especially in places like Cuzco, Peru. Modes of detection involve senses, such as sensitive, observant eyesight, and electromagnetically induced nerve signals interpreted as tinnitus, as traditionally indicated by ``Kokopelli's'' flute-playing, ``pins and needles,'' or even odor sensations. Recorded events show that youthful children are sometimes involved, as by Pacal's Classic-Mayan-era son, who became Kan Balum, Serpent Jaguar. Our intent is to check whether similar signals can be technologically identified in Brazil and New England. Site information investigated by us seems to be driven by the electromagnetic field. Enigmatic Brazilian locations should be technologically investigated with site correlations to other possible analogs, such as Florida's Chitto Tustenuggee site at Miramar. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.NES07.C2.6

  3. The story of the condom.

    PubMed

    Khan, Fahd; Mukhtar, Saheel; Dickinson, Ian K; Sriprasad, Seshadri

    2013-01-01

    Condoms have been a subject of curiosity throughout history. The idea of safer sex has been explored in ancient and modern history, and has been used to prevent venereal diseases. We conducted a historical and medical review of condoms using primary and secondary sources as well as using the RSM library and the internet. These resources show that the first use of a condom was that of King Minos of Crete. Pasiphae, his wife, employed a goat's bladder in the vagina so that King Minos would not be able to harm her as his semen was said to contain "scorpions and serpents" that killed his mistresses. To Egyptians, condom-like glans caps were dyed in different colours to distinguish between different classes of people and to protect themselves against bilharzia. The Ancient Romans used the bladders of animals to protect the woman; they were worn not to prevent pregnancy but to prevent contraction of venereal diseases. Charles Goodyear, the inventor, utilized vulcanization, the process of transforming rubber into malleable structures, to produce latex condoms. The greater use of condoms all over the world in the 20(th) and 21(st) centuries has been related to HIV. This account of the use of condoms demonstrates how a primitive idea turned into an object that is used globally with a forecast estimated at 18 billion condoms to be used in 2015 alone. PMID:23671357

  4. Occurrence of sulfated fucose branches in fucosylated chondroitin sulfate are essential for the polysaccharide effect preventing muscle damage induced by toxins and crude venom from Bothrops jararacussu snake.

    PubMed

    Monteiro-Machado, Marcos; Tomaz, Marcelo A; Fonseca, Roberto J C; Strauch, Marcelo A; Cons, Bruno L; Borges, Paula A; Patrão-Neto, Fernando C; Tavares-Henriques, Matheus S; Teixeira-Cruz, Jhonatha M; Calil-Elias, Sabrina; Cintra, Adélia C O; Martinez, Ana Maria B; Mourão, Paulo A S; Melo, Paulo A

    2015-05-01

    Snake envenoming is an important public health problem around the world, particularly in tropics. Beyond deaths, morbidity induced by snake venoms, such as myotoxicity, is of pivotal consequence to population. Bothrops jararacussu is the main venomous snake in southeast region of Brazil, and particularly presents strong myotoxic effect. The only available therapy, antibothropic antivenom, poorly affects venom-induced myotoxicity. The aim of this study is to assess the ability of fucosylated chondroitin sulfate (fucCS), a glycosaminoglycan with anticoagulant and antithrombotic properties, and its derivatives to inhibit toxic activities of B. jararacussu crude venom and its isolated toxins, named bothropstoxins (BthTX-I and BthTX-II). The in vitro myotoxic activities induced by crude venom, by BthTX-I alone and by toxins together were abolished by fucCS. Carboxyl reduction (fucCS-CR) kept this ability whereas defucosilation (defucCS) abrogates myoprotection. We observed the same pattern in the response of these polysaccharides in antagonizing the increase in plasma creatine kinase (CK) levels, the reduction of skeletal muscle CK content and the rise of myeloperoxidase (MPO) activity induced by crude venom and isolated toxins. FucCS inhibited edematogenic activity and partially prevented the reduction of total leukocytes in blood when pre-incubated with crude venom. Furthermore, the venom procoagulant effect was completely antagonized by increasing concentrations of fucCS, although this polyanion could stop neither the tail bleeding nor the skin hemorrhage induced by Bothrops jararaca venom. The B. jararacussu phospholipase, hyaluronidase, proteolytic and collagenase activities were inhibited in vitro. The results suggest that fucCS could be able to interact with both toxins, and it is able to inhibit BthTX-II phospholipase activity. Light microscopy of extensor digitorum longus muscle (EDL) muscle showed myoprotection by fucCS, once necrotic areas, edema and inflammatory cells were all decreased as compared to venom injection alone. Altogether, data show that fucCS was able to inhibit myotoxicity and inflammation induced by B. jararacussu venom and its phospholipase toxins, BthTX-I and BthTX-II. Thus, fucosylated chondroitin sulfate is a new polyanion with potential to be used as an adjuvant in the treatment of snakebites in the future. PMID:25702961

  5. Peptidomics of Three Bothrops Snake Venoms: Insights Into the Molecular Diversification of Proteomes and Peptidomes*

    PubMed Central

    Tashima, Alexandre K.; Zelanis, André; Kitano, Eduardo S.; Ianzer, Danielle; Melo, Robson L.; Rioli, Vanessa; Sant'anna, Sávio S.; Schenberg, Ana C. G.; Camargo, Antônio C. M.; Serrano, Solange M. T.

    2012-01-01

    Snake venom proteomes/peptidomes are highly complex and maintenance of their integrity within the gland lumen is crucial for the expression of toxin activities. There has been considerable progress in the field of venom proteomics, however, peptidomics does not progress as fast, because of the lack of comprehensive venom sequence databases for analysis of MS data. Therefore, in many cases venom peptides have to be sequenced manually by MS/MS analysis or Edman degradation. This is critical for rare snake species, as is the case of Bothrops cotiara (BC) and B. fonsecai (BF), which are regarded as near threatened with extinction. In this study we conducted a comprehensive analysis of the venom peptidomes of BC, BF, and B. jararaca (BJ) using a combination of solid-phase extraction and reversed-phase HPLC to fractionate the peptides, followed by nano-liquid chromatography-tandem MS (LC-MS/MS) or direct infusion electrospray ionization-(ESI)-MS/MS or MALDI-MS/MS analyses. We detected marked differences in the venom peptidomes and identified peptides ranging from 7 to 39 residues in length by de novo sequencing. Forty-four unique sequences were manually identified, out of which 30 are new peptides, including 17 bradykinin-potentiating peptides, three poly-histidine-poly-glycine peptides and interestingly, 10 l-amino acid oxidase fragments. Some of the new bradykinin-potentiating peptides display significant bradykinin potentiating activity. Automated database search revealed fragments from several toxins in the peptidomes, mainly from l-amino acid oxidase, and allowed the determination of the peptide bond specificity of proteinases and amino acid occurrences for the P4-P4? sites. We also demonstrate that the venom lyophilization/resolubilization process greatly increases the complexity of the peptidome because of the imbalance caused to the venom proteome and the consequent activity of proteinases on venom components. The use of proteinase inhibitors clearly showed different outcomes in the peptidome characterization and suggested that degradomic-peptidomic analysis of snake venoms is highly sensitive to the conditions of sampling procedures. PMID:22869554

  6. PepExplorer: A Similarity-driven Tool for Analyzing de Novo Sequencing Results *

    PubMed Central

    Leprevost, Felipe V.; Valente, Richard H.; Lima, Diogo B.; Perales, Jonas; Melani, Rafael; Yates, John R.; Barbosa, Valmir C.; Junqueira, Magno; Carvalho, Paulo C.

    2014-01-01

    Peptide spectrum matching is the current gold standard for protein identification via mass-spectrometry-based proteomics. Peptide spectrum matching compares experimental mass spectra against theoretical spectra generated from a protein sequence database to perform identification, but protein sequences not present in a database cannot be identified unless their sequences are in part conserved. The alternative approach, de novo sequencing, can make it possible to infer a peptide sequence directly from a mass spectrum, but interpreting long lists of peptide sequences resulting from large-scale experiments is not trivial. With this as motivation, PepExplorer was developed to use rigorous pattern recognition to assemble a list of homologue proteins using de novo sequencing data coupled to sequence alignment to allow biological interpretation of the data. PepExplorer can read the output of various widely adopted de novo sequencing tools and converge to a list of proteins with a global false-discovery rate. To this end, it employs a radial basis function neural network that considers precursor charge states, de novo sequencing scores, peptide lengths, and alignment scores to select similar protein candidates, from a target-decoy database, usually obtained from phylogenetically related species. Alignments are performed using a modified Smith–Waterman algorithm tailored for the task at hand. We verified the effectiveness of our approach using a reference set of identifications generated by ProLuCID when searching for Pyrococcus furiosus mass spectra on the corresponding NCBI RefSeq database. We then modified the sequence database by swapping amino acids until ProLuCID was no longer capable of identifying any proteins. By searching the mass spectra using PepExplorer on the modified database, we were able to recover most of the identifications at a 1% false-discovery rate. Finally, we employed PepExplorer to disclose a comprehensive proteomic assessment of the Bothrops jararaca plasma, a known biological source of natural inhibitors of snake toxins. PepExplorer is integrated into the PatternLab for Proteomics environment, which makes available various tools for downstream data analysis, including resources for quantitative and differential proteomics. PMID:24878498

  7. A new structurally atypical bradykinin-potentiating peptide isolated from Crotalus durissus cascavella venom (South American rattlesnake).

    PubMed

    Lopes, Denise M; Junior, Norberto E G; Costa, Paula P C; Martins, Patrícia L; Santos, Cláudia F; Carvalho, Ellaine D F; Carvalho, Maria D F; Pimenta, Daniel C; Cardi, Bruno A; Fonteles, Manassés C; Nascimento, Nilberto R F; Carvalho, Krishnamurti M

    2014-11-01

    Venom glands of some snakes synthesize bradykinin-potentiating peptides (BPP's) which increase bradykinin-induced hypotensive effect and decrease angiotensin I vasopressor effect by angiotensin-converting enzyme (ACE) inhibition. The present study shows a new BPP (BPP-Cdc) isolated from Crotalus durissus cascavella venom: Pro-Asn-Leu-Pro-Asn-Tyr-Leu-Gly-Ile-Pro-Pro. Although BPP-Cdc presents the classical sequence IPP in the C-terminus, it has a completely atypical N-terminal sequence, which shows very low homology with all other BPPs isolated to date. The pharmacological effects of BPP-Cdc were compared to BBP9a from Bothrops jararaca and captopril. BPP-Cdc (1 ?M) significantly increased BK-induced contractions (BK; 1 ?M) on the guinea pig ileum by 267.8% and decreased angiotensin I-induced contractions (AngI; 10 nM) by 62.4% and these effects were not significantly different from those of BPP9a (1 ?M) or captopril (200 nM). Experiments with 4-week hypertensive 2K-1C rats show that the vasopressor effect of AngI (10 ng) was decreased by 50 ?g BPP-Cdc (69.7%), and this result was similar to that obtained with 50 ?g BPP9a (69.8%). However, the action duration of BPP-Cdc (60 min) was 2 times greater than that of BPP-9a (30 min). On the other hand, the hypotensive effect of BK (250 ng) was significantly increased by 176.6% after BPP-Cdc (50 ?g) administration, value 2.5 times greater than that obtained with BPP9a administered at the same doses (71.4%). In addition, the duration of the action of BPP-Cdc (120 min) was also at least 4 times greater than that of BPP-9a (30 min). Taken together, these results suggest that BPP-Cdc presents more selective action on arterial blood system than BPP9a. Besides the inhibition of ACE, it may present other mechanisms of action yet to be elucidated. PMID:25091347

  8. Evaluation of the Lethal Potency of Scorpion and Snake Venoms and Comparison between Intraperitoneal and Intravenous Injection Routes

    PubMed Central

    Oukkache, Naoual; Jaoudi, Rachid El; Ghalim, Noreddine; Chgoury, Fatima; Bouhaouala, Balkiss; Mdaghri, Naima El; Sabatier, Jean-Marc

    2014-01-01

    Scorpion stings and snake bites are major health hazards that lead to suffering of victims and high mortality. Thousands of injuries associated with such stings and bites of venomous animals occur every year worldwide. In North Africa, more than 100,000 scorpion stings and snake bites are reported annually. An appropriate determination of the 50% lethal doses (LD50) of scorpion and snake venoms appears to be an important step to assess (and compare) venom toxic activity. Such LD50 values are also commonly used to evaluate the neutralizing capacity of specific anti-venom batches. In the present work, we determined experimentally the LD50 values of reference scorpion and snake venoms in Swiss mice, and evaluated the influence of two main venom injection routes (i.e., intraperitoneal (IP) versus intravenous (IV)). The analysis of experimental LD50 values obtained with three collected scorpion venoms indicates that Androctonus mauretanicus (Am) is intrinsically more toxic than Androctonus australis hector (Aah) species, whereas the latter is more toxic than Buthus occitanus (Bo). Similar analysis of three representative snake venoms of the Viperidae family shows that Cerastes cerastes (Cc) is more toxic than either Bitis arietans (Ba) or Macrovipera lebetina (Ml) species. Interestingly, the venom of Elapidae cobra snake Naja haje (Nh) is far more toxic than viper venoms Cc, Ml and Ba, in agreement with the known severity of cobra-related envenomation. Also, our data showed that viper venoms are about three-times less toxic when injected IP as compared to IV, distinct from cobra venom Nh which exhibited a similar toxicity when injected IP or IV. Overall, this study clearly highlights the usefulness of procedure standardization, especially regarding the administration route, for evaluating the relative toxicity of individual animal venoms. It also evidenced a marked difference in lethal activity between venoms of cobra and vipers, which, apart from the nature of toxins, might be attributed to the rich composition of high molecular weight enzymes in the case of viper venoms. PMID:24926799

  9. Involvement of Nitric Oxide on Bothropoides insularis Venom Biological Effects on Murine Macrophages In Vitro

    PubMed Central

    de Menezes, Ramon R. P. P. B.; Mello, Clarissa P.; Lima, Dânya B.; Tessarolo, Louise D.; Sampaio, Tiago Lima; Paes, Lívia C. F.; Alves, Natacha T. Q.; Assis Junior, Eudmar M.; Lima Junior, Roberto C. P.; Toyama, Marcos H.; Martins, Alice M. C.

    2016-01-01

    Viperidae venom has several local and systemic effects, such as pain, edema, inflammation, kidney failure and coagulopathy. Additionally, bothropic venom and its isolated components directly interfere on cellular metabolism, causing alterations such as cell death and proliferation. Inflammatory cells are particularly involved in pathological envenomation mechanisms due to their capacity of releasing many mediators, such as nitric oxide (NO). NO has many effects on cell viability and it is associated to the development of inflammation and tissue damage caused by Bothrops and Bothropoides venom. Bothropoides insularis is a snake found only in Queimada Grande Island, which has markedly toxic venom. Thus, the aim of this work was to evaluate the biological effects of Bothropoides insularis venom (BiV) on RAW 264.7 cells and assess NO involvement. The venom was submitted to colorimetric assays to identify the presence of some enzymatic components. We observed that BiV induced H2O2 production and showed proteolytic and phospholipasic activities. RAW 264.7 murine macrophages were incubated with different concentrations of BiV and then cell viability was assessed by MTT reduction assay after 2, 6, 12 and 24 hours of incubation. A time- and concentration-dependent effect was observed, with a tendency to cell proliferation at lower BiV concentrations and cell death at higher concentrations. The cytotoxic effect was confirmed after lactate dehydrogenase (LDH) measurement in the supernatant from the experimental groups. Flow cytometry analyses revealed that necrosis is the main cell death pathway caused by BiV. Also, BiV induced NO release. The inhibition of both proliferative and cytotoxic effects with L-NAME were demonstrated, indicating that NO is important for these effects. Finally, BiV induced an increase in iNOS expression. Altogether, these results demonstrate that B. insularis venom have proliferative and cytotoxic effects on macrophages, with necrosis participation. We also suggest that BiV acts by inducing iNOS expression and causing NO release. PMID:26974665

  10. Evolution of CRISPs associated with toxicoferan-reptilian venom and mammalian reproduction.

    PubMed

    Sunagar, Kartik; Johnson, Warren E; O'Brien, Stephen J; Vasconcelos, Vítor; Antunes, Agostinho

    2012-07-01

    Cysteine-rich secretory proteins (CRISPs) are glycoproteins found exclusively in vertebrates and have broad diversified functions. They are hypothesized to play important roles in mammalian reproduction and in reptilian venom, where they disrupt homeostasis of the prey through several mechanisms, including among others, blockage of cyclic nucleotide-gated and voltage-gated ion channels and inhibition of smooth muscle contraction. We evaluated the molecular evolution of CRISPs in toxicoferan reptiles at both nucleotide and protein levels relative to their nonvenomous mammalian homologs. We show that the evolution of CRISP gene in these reptiles is significantly influenced by positive selection and in snakes (ω = 3.84) more than in lizards (ω = 2.33), whereas mammalian CRISPs were under strong negative selection (CRISP1 = 0.55, CRISP2 = 0.40, and CRISP3 = 0.68). The use of ancestral sequence reconstruction, mapping of mutations on the three-dimensional structure, and detailed evaluation of selection pressures suggests that the toxicoferan CRISPs underwent accelerated evolution aided by strong positive selection and directional mutagenesis, whereas their mammalian homologs are constrained by negative selection. Gene and protein-level selection analyses identified 41 positively selected sites in snakes and 14 sites in lizards. Most of these sites are located on the molecular surface (nearly 76% in snakes and 79% in lizards), whereas the backbone of the protein retains a highly conserved structural scaffold. Nearly 46% of the positively selected sites occur in the cysteine-rich domain of the protein. This directional mutagenesis, where the hotspots of mutations are found on the molecular surface and functional domains of the protein, acts as a diversifying mechanism for the exquisite biological targeting of CRISPs in toxicoferan reptiles. Finally, our analyses suggest that the evolution of toxicoferan-CRISP venoms might have been influenced by the specific predatory mechanism employed by the organism. CRISPs in Elapidae, which mostly employ neurotoxins, have experienced less positive selection pressure (ω = 2.86) compared with the "nonvenomous" colubrids (ω = 4.10) that rely on grip and constriction to capture the prey, and the Viperidae, a lineage that mostly employs haemotoxins (ω = 4.19). Relatively lower omega estimates in Anguimorph lizards (ω = 2.33) than snakes (ω = 3.84) suggests that lizards probably depend more on pace and powerful jaws for predation than venom. PMID:22319140

  11. Diversity, natural history, and geographic distribution of snakes in the Caatinga, Northeastern Brazil.

    PubMed

    Guedes, Thaís B; Nogueira, Cristiano; Marques, Otavio A V

    2014-01-01

    The present study is a synthesis on snake diversity and distribution in the Caatinga region of northeastern Brazil, providing an updated species list and data on natural history and geographic distribution. Our study is based on the careful revision of 7,102 voucher specimens, housed in 17 herpetological collections, complemented by data on taxonomic literature. We recorded a total of 112 snake species in the Caatinga, belonging to nine families: Anomalepididae, Leptotyphlopidae, Typhlopidae, Aniliidae, Boidae, Viperidae, Elapidae, Colubridae, and Dipsadidae. Our list includes at least 13 never recorded species for this region, as well as distribution records for all species known from the Caatinga (including expansion and new records of distribution). The snake assemblage of the Caatinga is complex, sharing species with other continental open areas (38.4%), forested areas (27.7%), and both open and forested areas (32.1%). The richest areas were isolated plateaus, followed by contact areas, semi-arid caatinga, and sandy dunes of the São Franscisco River. We identified 22 Caatinga endemic species with the sandy dunes of São Franscico River showing the highest endemism level (12 species, with six endemic species restricted to the area) followed by semi-arid caatinga, and isolated plateaus (eight endemic species each, and six and three endemic species with restricted distribution to each area, respectively). Most species show relatively restricted ranges in parts of the Caatinga. The snake assemblage in Caatinga includes mainly terrestrial species (38.4%), followed by fossorial/cryptozoic (26.8%), arboreal/semi-arboreal (26.8%), and aquatic/semi-aquatic (7.1%) species. Vertebrates are the most important dietary item (80.4%), with 56.6% of species being generalist consumers of this kind of prey; 24.4% are frog-eaters, 7.8% prey on caecilians/amphisbaenians, 6.7% lizard-eaters, 3.3% mammal-eaters, and 1.1% are fish-eaters. Only 18.7% of the snakes eat invertebrate prey, as arthropods, annelids, and mollusks. In relation to time of activity, 35.7% of snakes are both diurnal and nocturnal, 33.0% are strictly nocturnal, and 30.4% are diurnal. The data provided herein increase the list of Caatinga snake species from 50 to 112, and includes detailed maps and information on geographic distribution. The Caatinga snake assemblage shows high richness and endemism levels, and our results highlight the usefulness of basic natural history data and revision of voucher specimens as baseline information for biogeographic studies and conservation strategies.  PMID:25283535

  12. Development of Equine IgG Antivenoms against Major Snake Groups in Mozambique

    PubMed Central

    Guidolin, Felipe Raimondi; Caricati, Celso Pereira; Marcelino, José Roberto; da Silva, Wilmar Dias

    2016-01-01

    Background Snake envenoming is a significant public health problem in underdeveloped and developing countries. In sub-Saharan Africa, it is estimated that 90,000–400,000 envenomations occur each year, resulting in 3,500–32,000 deaths. Envenomings are caused by snakes from the Viperidae (Bitis spp. and Echis spp.) and Elapidae (Naja spp. and Dendroaspis spp.) families. The African continent has been suffering from a severe antivenom crisis and current antivenom production is only sufficient to treat 25% of snakebite cases. Our aim is to develop high-quality antivenoms against the main snake species found in Mozambique. Methods Adult horses primed with the indicated venoms were divided into 5 groups (B. arietans; B. nasicornis + B. rhinoceros; N. melanoleuca; N. mossambica; N. annulifera + D. polylepis + D. angusticeps) and reimmunized two times for antivenom production. Blood was collected, and plasma was separated and subjected to antibody purification using caprylic acid. Plasmas and antivenoms were subject to titration, affinity determination, cross-recognition assays and in vivo venom lethality neutralization. A commercial anti-Crotalic antivenom was used for comparison. Results The purified antivenoms exhibited high titers against B. arietans, B. nasicornis and B. rhinoceros (5.18 x 106, 3.60 x 106 and 3.50 x 106 U-E/mL, respectively) and N. melanoleuca, N. mossambica and N. annulifera (7.41 x 106, 3.07 x 106 and 2.60 x 106 U-E/mL, respectively), but lower titers against the D. angusticeps and D. polylepis (1.87 x 106 and 1.67 x 106 U-E/mL). All the groups, except anti-N. melanoleuca, showed significant differences from the anti-Crotalic antivenom (7.55 x 106 U-E/mL). The affinity index of all the groups was high, ranging from 31% to 45%. Cross-recognition assays showed the recognition of proteins with similar molecular weight in the venoms and may indicate the possibility of paraspecific neutralization. The three monospecific antivenoms were able to provide in vivo protection. Conclusion Our results indicate that the anti-Bitis and anti-Naja antivenoms developed would be useful for treating snakebite envenomations in Mozambique, although their effectiveness should to be increased. We propose instead the development of monospecific antivenoms, which would serve as the basis for two polyvalent antivenoms, the anti-Bitis and anti-Elapidae. Polyvalent antivenoms represent an increase in treatment quality, as they have a wider range of application and are easier to distribute and administer to snake envenoming victims. PMID:26730709

  13. Advanced Test Reactor Core Modeling Update Project Annual Report for Fiscal Year 2012

    SciTech Connect

    David W. Nigg, Principal Investigator; Kevin A. Steuhm, Project Manager

    2012-09-01

    Legacy computational reactor physics software tools and protocols currently used for support of Advanced Test Reactor (ATR) core fuel management and safety assurance, and to some extent, experiment management, are inconsistent with the state of modern nuclear engineering practice, and are difficult, if not impossible, to properly verify and validate (V&V) according to modern standards. Furthermore, the legacy staff knowledge required for application of these tools and protocols from the 1960s and 1970s is rapidly being lost due to staff turnover and retirements. In late 2009, the Idaho National Laboratory (INL) initiated a focused effort, the ATR Core Modeling Update Project, to address this situation through the introduction of modern high-fidelity computational software and protocols. This aggressive computational and experimental campaign will have a broad strategic impact on the operation of the ATR, both in terms of improved computational efficiency and accuracy for support of ongoing DOE programs as well as in terms of national and international recognition of the ATR National Scientific User Facility (NSUF). The ATR Core Modeling Update Project, targeted for full implementation in phase with the next anticipated ATR Core Internals Changeout (CIC) in the 2014-2015 time frame, began during the last quarter of Fiscal Year 2009, and has just completed its third full year. Key accomplishments so far have encompassed both computational as well as experimental work. A new suite of stochastic and deterministic transport theory based reactor physics codes and their supporting nuclear data libraries (HELIOS, KENO6/SCALE, NEWT/SCALE, ATTILA, and an extended implementation of MCNP5) has been installed at the INL under various licensing arrangements. Corresponding models of the ATR and ATRC are now operational with all five codes, demonstrating the basic feasibility of the new code packages for their intended purpose. Of particular importance, a set of as-run core depletion HELIOS calculations for all ATR cycles since August 2009, Cycle 145A through Cycle 151B, was successfully completed during 2012. This major effort supported a decision late in the year to proceed with the phased incorporation of the HELIOS methodology into the ATR Core Safety Analysis Package (CSAP) preparation process, in parallel with the established PDQ-based methodology, beginning late in Fiscal Year 2012. Acquisition of the advanced SERPENT (VTT-Finland) and MC21 (DOE-NR) Monte Carlo stochastic neutronics simulation codes was also initiated during the year and some initial applications of SERPENT to ATRC experiment analysis were demonstrated. These two new codes will offer significant additional capability, including the possibility of full-3D Monte Carlo fuel management support capabilities for the ATR at some point in the future. Finally, a capability for rigorous sensitivity analysis and uncertainty quantification based on the TSUNAMI system has been implemented and initial computational results have been obtained. This capability will have many applications as a tool for understanding the margins of uncertainty in the new models as well as for validation experiment design and interpretation.

  14. Development of 3D full-core ERANOS-2.2/MCNPX-2.7.0 models and neutronic analysis of the BFS-2 zero-power facility

    SciTech Connect

    Girardin, G.; Alonso, M.; Mikityuk, K.

    2012-07-01

    The present paper is addressing the development and validation against experimental data of 3D full-core models of the BFS-2 zero-power fast-reactor using both the deterministic system code ERANOS-2.2 and the stochastic code MCNPX-2.7.0. The model configuration of BFS considered for analysis is the BFS-62-3A benchmark. To extend the - deterministic/stochastic - code-to-code comparison, neutronic parameters, i.e. reactivity, neutron spectrum and reaction rates, were also simulated at the cell level with the Monte Carlo code SERPENT-1.1.7 with two modern data libraries, ENDF-B/VII and JEFF-3.1.1. The BFS-2 critical zero-power facility at the Inst. of Physics and Power Engineering (IPPE) was designed for simulations of the core and shielding of sodium-cooled, fast reactors, for neutron data validation and comparison with experimental results. At the BFS-2 facility, the BFS-62-3A critical benchmark experiment was set-up as a mock-up of the BN-600 reactor, with hybrid MOX fuel and stainless steel reflectors. A UO{sub 2} blanket and a large non-homogeneous stainless-steel reflector surround the core. The lattice is hexagonal of pitch 5.1 cm and metallic dowels are used to keep in central position cylindrical rods made of different types of material (fissile, fertile, blanket, plenum, shielding and absorber). A typical subassembly is formed in piling up various pellets of about 1 cm in height and 4.6 cm in diameter, conferring large heterogeneity in the axial direction. The full-core model development was a complex task due to the large number of subassemblies and the axial subassembly heterogeneity. In ERANOS-2.2, it was necessary to homogenize axially per region the pellets used to form the subassembly. The self-shielded macroscopic cross-sections were calculated using the cell code ECCO in association with JEFF-3.1 and ENDF/B-VI.8 data libraries. The core calculations were performed with broad cross-sections data in 33 neutron energy groups with the solver AVNM in the diffusion approximation, mostly. In MCNPX-2.7.0, a step-by-step approach was used, starting with a model in which the fissile rods were simulated on a homogeneous level, to finally integrate the actual heterogeneous description of the subassemblies. The code-to-code cell analysis performed between ECCO, SERPENT and MCNPX with different modern nuclear data library revealed that the results for the infinite multiplication factor between Monte Carlo and deterministic analysis are in good agreement ({Delta}p < 100 pcm). The differences between the results were observed to be larger for the neutron data libraries, with reactivity differences up to 350 pcm. (authors)

  15. Stellar

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This eerie, dark structure, resembling an imaginary sea serpent's head, is a column of cool molecular hydrogen gas (two atoms of hydrogen in each molecule) and dust that is an incubator for new stars. The stars are embedded inside finger-like protrusions extending from the top of the nebula. Each 'fingertip' is somewhat larger than our own solar system. The pillar is slowly eroding away by the ultraviolet light from nearby hot stars, a process called 'photoevaporation.' As it does, small globules of especially dense gas buried within the cloud is uncovered. These globules have been dubbed 'EGGs' -- an acronym for 'Evaporating Gaseous Globules.' The shadows of the EGGs protect gas behind them, resulting in the finger-like structures at the top of the cloud. Forming inside at least some of the EGGs are embryonic stars -- stars that abruptly stop growing when the EGGs are uncovered and they are separated from the larger reservoir of gas from which they were drawing mass. Eventually the stars emerge, as the EGGs themselves succumb to photoevaporation. The stellar EGGS are found, appropriately enough, in the 'Eagle Nebula' (also called M16 -- the 16th object in Charles Messier's 18th century catalog of 'fuzzy' permanent objects in the sky), a nearby star-forming region 7,000 light-years away in the constellation Serpens. The picture was taken on April 1, 1995 with the Hubble Space Telescope Wide Field and Planetary Camera 2. The color image is constructed from three separate images taken in the light of emission from different types of atoms. Red shows emission from singly-ionized sulfur atoms. Green shows emission from hydrogen. Blue shows light emitted by doubly-ionized oxygen atoms.

  16. STELLAR 'EGGS' EMERGE FROM MOLECULAR CLOUD (Star-Birth Clouds in M16)

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This eerie, dark structure, resembling an imaginary sea serpent's head, is a column of cool molecular hydrogen gas (two atoms of hydrogen in each molecule) and dust that is an incubator for new stars. The stars are embedded inside finger-like protrusions extending from the top of the nebula. Each 'fingertip' is somewhat larger than our own solar system. The pillar is slowly eroding away by the ultraviolet light from nearby hot stars, a process called 'photoevaporation'. As it does, small globules of especially dense gas buried within the cloud is uncovered. These globules have been dubbed 'EGGs' -- an acronym for 'Evaporating Gaseous Globules'. The shadows of the EGGs protect gas behind them, resulting in the finger-like structures at the top of the cloud. Forming inside at least some of the EGGs are embryonic stars -- stars that abruptly stop growing when the EGGs are uncovered and they are separated from the larger reservoir of gas from which they were drawing mass. Eventually the stars emerge, as the EGGs themselves succumb to photoevaporation. The stellar EGGS are found, appropriately enough, in the 'Eagle Nebula' (also called M16 -- the 16th object in Charles Messier's 18th century catalog of 'fuzzy' permanent objects in the sky), a nearby star-forming region 6,500 light-years away in the constellation Serpens. The picture was taken on April 1, 1995 with the Hubble Space Telescope Wide Field and Planetary Camera 2. The color image is constructed from three separate images taken in the light of emission from different types of atoms. Red shows emission from singly-ionized sulfur atoms. Green shows emission from hydrogen. Blue shows light emitted by doubly- ionized oxygen atoms. Credit: Jeff Hester and Paul Scowen (Arizona State University), and NASA Image files in GIF and JPEG format and captions may be accessed on Internet via anonymous ftp from oposite.stsci.edu in /pubinfo:

  17. Introduction to the symposium "New frontiers from marine snakes to marine ecosystems".

    PubMed

    Lillywhite, Harvey B; Brischoux, François

    2012-08-01

    Interest in sea snakes and mythological "sea serpents" dates to ancient times and is represented in the writings of Aristotle, early voyagers, and explorers, and references in the Bible. Since then, awareness of the myriad species of snakes inhabiting the oceans has grown at a gradual pace. Scientific investigations into the biology of marine snakes-especially those in behavior, physiology, and other disciplines requiring living animals or tissues-have been comparatively challenging owing to difficulties in acquiring, transporting, handling, and husbanding these secondarily marine vertebrates. A broadening perspective with increasing interest in these animals peaked during the 1960s and 1970s, and literature from this period contributed to a growing knowledge that marine snakes comprise a very diverse fauna and are a significant part of marine ecosystems. Two persons figured prominently as influential drivers of research on sea snakes during this period, namely William Dunson and Harold Heatwole, and this symposium recognizes the contributions of these two individuals. Following a decline in scientific publications on sea snakes during the 1980s and 1990s, there has been a renaissance of scientific interest in recent years, and a wealth of new research findings has improved the understanding of phylogeny and diversity of marine snakes while simultaneously recognizing threats to marine ecosystems arising from climate change and other anthropogenic causes. The purposes of the symposium are to (1) illustrate the importance and relevance of sea snakes as contributors to better understanding a range of issues in marine biology, (2) establish and promote the use of marine systems as models for investigating conceptual issues related to environment, changing climate, and persistence of biological communities, with focus on marine snakes as novel or useful examples, (3) promote interest in sea snakes as useful organisms for study by scientists in a range of disciplines who might presently work with other organisms or systems, and (4) identify leading-edge topics for which studies of marine snakes might contribute uniquely to the advancement of research. PMID:22537936

  18. Isotopic analysis of Bothrops atrox in Amazonian forest

    NASA Astrophysics Data System (ADS)

    Martinez, M. G.; Silva, A. M.; Chalkidis, H.; de Oliveira Júnior, R. C.; Camargo, P. B.

    2012-12-01

    The poisoning of snakes is considered a public health problem, especially in populations from rural areas of tropical and subtropical countries. In Brazil, the 26,000 snakebites, 90% are of the genus Bothrops, and Bothrops atrox species predominant in the Amazon region including all the Brazilian Amazon. Research shows that using stable isotopes, we can verify the isotopic composition of tissues of animals that depend mainly on food, water ingested and inhaled gases. For this study, samples taken from Bothrops atrox (B. atrox), in forest using pitfall traps and fall ("Pitt-fall traps with drift fence"). The analyzes were performed by mass spectrometry, where the analytical error is 0.3‰ for carbon and 0.5‰ to nitrogen. The results of the forest animals are significantly different from results of animal vivarium. The average values of the tissues and venoms of snakes of the forest for carbon-13 and nitrogen-15 are: ?13C = -24.68‰ and ?15N = 14.22‰ and mean values of tissue and poisons snakes vivarium (Instituto Butantan) to carbon-13 and nitrogen-15 are ?13C = -20.47‰ and ?15N = 8.36‰, with a significantly different due to different sources of food animals. Based on all results isotopic ?13C and ?15N, we can suggest that changes as the power of the serpent, (nature and captivity), changes occur in relation to diet and environment as the means of the isotopic data are quite distinct, showing that these changes can also cause metabolic changes in the body of the animal itself and the different periods of turnover of each tissue analyzed.

  19. High conversion Th-U{sup 233} fuel assembly for current generation of PWRs

    SciTech Connect

    Baldova, D.; Fridman, E.

    2012-07-01

    This paper presents a preliminary design of a high conversion Th-U{sup 233} fuel assembly applicable for current generation of Pressurized Water Reactor (PWRs). The considered fuel assembly has a typical 17 x 17 PWR lattice. However in order to increase the conversion of Th{sup 232} to U{sup 233}, the assembly was subdivided into the two regions called seed and blanket. The central seed region has a higher than blanket U{sup 233} content and acts as a neutron source for the peripheral blanket region. The latest acts as a U{sup 233} breeder. While the seed fuel pins have a standard dimensions the blanket fuel radius was increased in order to reduce the moderation and to facilitate the resonance neutron absorption in blanket Th{sup 232}. The U{sup 233} content in the seed and blanket regions was optimized to achieve maximal initial to discharged fissile inventory ratio (FIR) taking into account the target fuel cycle length of 12 months with 3-batch reloading scheme. In this study the neutronic calculations were performed on the fuel assembly level using Helios deterministic lattice transport code. The fuel cycle length and the core k{sub eff} were estimated by applying the Non Linear Reactivity Model. The applicability of the HELIOS code for the analysis of the Th-based high conversion designs was confirmed with the help of continuous-energy Monte-Carlo code SERPENT. The results of optimization studies show that for the heterogeneous seed and blanket (SB) fuel assembly the FIR of about 0.95 can be achieved. (authors)

  20. Chimeric creatures in Greek mythology and reflections in science.

    PubMed

    Bazopoulou-Kyrkanidou, E

    2001-04-15

    "The Chimaera" in Homer's Iliad, "was of divine stock, not of men, in the forepart a lion, in the hinder a serpent, and in the midst a goat, ellipsis Bellerophon slew her, trusting in the signs of the gods." In Hesiod's Theogony it is emphasized that "Chimaera ellipsis had three heads, one of a grim-eyed lion, another of a goat, and another of a snakeellipsis". In addition to this interspecies animal chimera, human/animal chimeras are referred to in Greek mythology, preeminent among them the Centaurs and the Minotaur. The Centaurs, as horse/men, first appear in Geometric and early Archaic art, but in the literature not until early in the fifth century B.C. The bullheaded-man Minotaur, who is not certainly attested in the literary evidence until circa 500 B.C., first appears in art about 650 B.C. Attempts, in the fourth century B.C. and thereafter, to rationalize their mythical appearance were in vain; their chimeric nature retained its fascinating and archetypal form over the centuries. Early in the 1980s, experimental sheep/goat chimeras were produced removing the reproductive barrier between these two animal species. Late in the 1990s, legal, political, ethical, and moral fights loomed over a patent bid on human/animal chimeras. Chimeric technology is recently developed; however, the concept of chimerism has existed in literary and artistic form in ancient mythology. This is yet another example where art and literature precede scientific research and development. PMID:11337752

  1. Optimizing the implementation of the target motion sampling temperature treatment technique - How fast can it get?

    SciTech Connect

    Tuomas, V.; Jaakko, L.

    2013-07-01

    This article discusses the optimization of the target motion sampling (TMS) temperature treatment method, previously implemented in the Monte Carlo reactor physics code Serpent 2. The TMS method was introduced in [1] and first practical results were presented at the PHYSOR 2012 conference [2]. The method is a stochastic method for taking the effect of thermal motion into account on-the-fly in a Monte Carlo neutron transport calculation. It is based on sampling the target velocities at collision sites and then utilizing the 0 K cross sections at target-at-rest frame for reaction sampling. The fact that the total cross section becomes a distributed quantity is handled using rejection sampling techniques. The original implementation of the TMS requires 2.0 times more CPU time in a PWR pin-cell case than a conventional Monte Carlo calculation relying on pre-broadened effective cross sections. In a HTGR case examined in this paper the overhead factor is as high as 3.6. By first changing from a multi-group to a continuous-energy implementation and then fine-tuning a parameter affecting the conservativity of the majorant cross section, it is possible to decrease the overhead factors to 1.4 and 2.3, respectively. Preliminary calculations are also made using a new and yet incomplete optimization method in which the temperature of the basis cross section is increased above 0 K. It seems that with the new approach it may be possible to decrease the factors even as low as 1.06 and 1.33, respectively, but its functionality has not yet been proven. Therefore, these performance measures should be considered preliminary. (authors)

  2. Transmutation Analysis of Enriched Uranium and Deep Burn High Temperature Reactors

    SciTech Connect

    Michael A. Pope

    2012-07-01

    High temperature reactors (HTRs) have been under consideration for production of electricity, process heat, and for destruction of transuranics for decades. As part of the transmutation analysis efforts within the Fuel Cycle Research and Development (FCR&D) campaign, a need was identified for detailed discharge isotopics from HTRs for use in the VISION code. A conventional HTR using enriched uranium in UCO fuel was modeled having discharge burnup of 120 GWd/MTiHM. Also, a deep burn HTR (DB-HTR) was modeled burning transuranic (TRU)-only TRU-O2 fuel to a discharge burnup of 648 GWd/MTiHM. For each of these cases, unit cell depletion calculations were performed with SCALE/TRITON. Unit cells were used to perform this analysis using SCALE 6.1. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were first set by using Serpent calculations to match a spectral index between unit cell and whole core domains. In the case of the DB-HTR, the unit cell which was arrived at in this way conserved the ratio of fuel to moderator found in a single block of fuel. In the conventional HTR case, a larger moderator-to-fuel ratio than that of a single block was needed to simulate the whole core spectrum. Discharge isotopics (for 500 nuclides) and one-group cross-sections (for 1022 nuclides) were delivered to the transmutation analysis team. This report provides documentation for these calculations. In addition to the discharge isotopics, one-group cross-sections were provided for the full list of 1022 nuclides tracked in the transmutation library.

  3. Isotopic change in the tissues of Bothrops atrox in captivity collected from environments of the eastern Amazon

    NASA Astrophysics Data System (ADS)

    Martinez, M. G.; Chalkidis, H. D.; Amazonas, D. R.; da Silva, A. M.; De Oliveira, R., Jr.; Camargo, P. B.

    2013-12-01

    The Bothrops atrox is little studied because it is sympatric Amazonian animals, and very little is known about the ecology and natural history of this species. It has a generalist diet and the distribution of this species is very wide. The adult animals forage mostly on the ground, while the younger animals prefer to stay on the vegetation. They are easily find in the rainy months in areas near lakes and seasonally flooded and are difficult to find in the driest months, a period where there is less availability of preys in these environments. Due to its aggressiveness, is considered one of the most feared snakes in South America and in the eastern Amazon, being responsible for the largest number of snakebites in the region. Through stable isotope carbon-13 and nitrogen-15, is intended to characterize the variations of the feeding habits of these collected animals in different environments and also when they are kept in captivity, feeding the animal's bioterium. The serpents were collected in environments with different land uses, such as native forest, savannah, pasture and have been brought to the serpentarium Integrated College Tapajos (FIT), being retained in order to Samplings throughout the experiment with feeding mice's own bioterium. When these snakes came from different locations, samples were collected scales and blood (T0), before receiving the new supply (captive), and every time we fed the mice the vivarium, new tissue samples were collected, (T1, T2, T3) to exchange all the nature of food for the food captivity.Based on the results of δ13C and δ15N, the samples collected in the tissues of snakes of different environments (nature and captivity), it was observed that changes in food sources reflect changes in tissues (blood and scales), also reflecting the production of poison different periods of turnover of absorbed material in those tissues, contributing to the study of animal ecology and behavior in relation to habitat.

  4. Organization and operation of the marine ornamental fish and invertebrate export fishery in Puerto Rico.

    PubMed

    Legorel, Richard S; Hardin, Mark P; Ter-Ghazaryan, Diana

    2005-05-01

    This fishery was examined utilizing public records, stakeholder interviews, and operational site visits to describe the fishery for the Puerto Rico Coral Reef Advisory Committee as a first step toward development of policies for the effective management of these natural resources. The fishery is not large, including fewer than 20 licensed fishers operating primarily on the west end of the island. Only three operators export product, with the remaining fishers providing specimens to the exporters based upon customer orders. Most collection of coral reef species occurs over hard rubble zones mixed with relic reef structures and rock, or on the sides and frontal areas of active reefs. Other species are collected from among mangrove prop root zones, tidal flats, and seagrass beds. Collections are made using simple barrier and dip nets for fish and motile invertebrates such as shrimp. Invertebrates such as crabs, starfish, and sea cucumbers are commonly collected by overturning small rocks, gathering the specimens, and then replacing the rocks in their original positions. Specimens are carried to the boat and transferred to individual cup holders to maximize survival. Although statements concerning former use of chemicals to assist capture were noted, no evidence of current chemical use was observed. Specimens are held in re-circulating seawater systems onshore until collections are aggregated and shipped. The fishery strives to operate with mortality of<1%, as mortalities of>3% are described as unacceptable to customers. More than 100 fish species are collected in this fishery, but the top ten species account for >70% of the total numbers and >60% of the total value of the fishery, with a single species, Gramma loreto (Royal Gramma), comprising >40% of the numbers. More than 100 species of invertebrates are collected, but this fishery is also dominated by a handful of species, including anemones, hermit crabs, turbo snails, serpent starfish, and feather duster polychaetes. PMID:17465154

  5. Carbon Isotopes of Alkanes in Hydrothermal Abiotic Organic Synthesis Processes at High Temperatures and Pressures: An Experimental Study

    NASA Technical Reports Server (NTRS)

    Fu, Qi; Socki, Richard A.; Niles, Paul B.

    2010-01-01

    Observation of methane in the Martian atmosphere has been reported by different detection techniques [1-4]. With more evidence showing extensive water-rock interaction in Martian history [5-7], abiotic formation by Fischer-Tropsch Type (FTT) synthesis during serpentization reactions may be one possible process responsible for methane generation on Mars [8, 9]. While the experimental studies performed to date leave little doubt that chemical reactions exist for the abiotic synthesis of organic compounds by mineral surface-catalyzed reactions [10-12], little is known about the reaction pathways by which CO2 and/or CO are reduced under hydrothermal conditions. Carbon and hydrogen isotope measurements of alkanes have been used as an effective tool to constrain the origin and reaction pathways of hydrocarbon formation. Alkanes generated by thermal breakdown of high molecular weight organic compounds have carbon and hydrogen isotopic signatures completely distinct from those formed abiotically [13-15]. Recent experimental studies, however, showed that different abiogenic hydrocarbon formation processes (e.g., polymerization vs. depolymerization) may have different carbon and hydrogen isotopic patterns [16]. Results from previous experiments studying decomposition of higher molecular weight organic compounds (lignite) also suggested that pressure could be a crucial factor affecting fractionation of carbon isotopes [17]. Under high pressure conditions, no experimental data are available describing fractionation of carbon isotope during mineral catalyzed FTT synthesis. Thus, hydrothermal experiments present an excellent opportunity to provide the requisite carbon isotope data. Such data can also be used to identify reaction pathways of abiotic organic synthesis under experimental conditions.

  6. Hydrogen Isotope Measurements of Organic Acids and Alcohols by Pyrolysis-GC-MS-TC-IRMS: Application to Analysis of Experimentally Derived Hydrothermal Mineral-Catalyzed Organic Products

    NASA Technical Reports Server (NTRS)

    Socki, Richard A.; Fu, Qi; Niles, Paul B.; Gibson, Everett K., Jr.

    2012-01-01

    We report results of experiments to measure the H isotope composition of organic acids and alcohols. These experiments make use of a pyroprobe interfaced with a GC and high temperature extraction furnace to make quantitative H isotope measurements. This work compliments our previous work that focused on the extraction and analysis of C isotopes from the same compounds [1]. Together with our carbon isotope analyses our experiments serve as a "proof of concept" for making C and H isotope measurements on more complex mixtures of organic compounds on mineral surfaces in abiotic hydrocarbon formation processes at elevated temperatures and pressures. Our motivation for undertaking this work stems from observations of methane detected within the Martian atmosphere [2-5], coupled with evidence showing extensive water-rock interaction during Mars history [6-8]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization [9,10]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [11-13]. Our H isotope measurements utilize an analytical technique combining Pyrolysis-Gas Chromatograph-Mass Spectrometry-High Temperature Conversion-Isotope Ratio Mass Spectrometry (Py-GC-MS-TC-IRMS). This technique is designed to carry a split of the pyrolyzed GC-separated product to a Thermo DSQII quadrupole mass spectrometer as a means of making qualitative and semi-quantitative compositional measurements of separated organic compounds, therefore both chemical and isotopic measurements can be carried out simultaneously on the same sample.

  7. Phylogeography of the Mekong mud snake (Enhydris subtaeniata): the biogeographic importance of dynamic river drainages and fluctuating sea levels for semiaquatic taxa in Indochina

    PubMed Central

    Lukoschek, Vimoksalehi; Osterhage, Jennifer L; Karns, Daryl R; Murphy, John C; Voris, Harold K

    2011-01-01

    During the Cenozoic, Southeast Asia was profoundly affected by plate tectonic events, dynamic river systems, fluctuating sea levels, shifting coastlines, and climatic variation, which have influenced the ecological and evolutionary trajectories of the Southeast Asian flora and fauna. We examined the role of these paleogeographic factors on shaping phylogeographic patterns focusing on a species of semiaquatic snake, Enhydris subtaeniata (Serpentes: Homalopsidae) using sequence data from three mitochondrial fragments (cytochrome b, ND4, and ATPase—2785 bp). We sampled E. subtaeniata from seven locations in three river drainage basins that encompassed most of this species’ range. Genetic diversities were typically low within locations but high across locations. Moreover, each location had a unique suite of haplotypes not shared among locations, and pairwise ?ST values (0.713–0.998) were highly significant between all location pairs. Relationships among phylogroups were well resolved and analysis of molecular variance (AMOVA) revealed strong geographical partitioning of genetic variance among the three river drainage basins surveyed. The genetic differences observed among the populations of E. subtaeniata were likely shaped by the Quaternary landscapes of Indochina and the Sunda Shelf. Historically, the middle and lower Mekong consisted of strongly dissected river valleys separated by low mountain ranges and much of the Sunda Shelf consisted of lowland river valleys that served to connect faunas associated with major regional rivers. It is thus likely that the contemporary genetic patterns observed among populations of E. subtaeniata are the result of their histories in a complex terrain that created abundant opportunities for genetic isolation and divergence yet also provided lowland connections across now drowned river valleys. PMID:22393504

  8. CURRENT BUILDUP IN EMERGING SERPENTINE FLUX TUBES

    SciTech Connect

    Pariat, E.; Masson, S.; Aulanier, G.

    2009-08-20

    The increase of magnetic flux in the solar atmosphere during active-region formation involves the transport of the magnetic field from the solar convection zone through the lowest layers of the solar atmosphere, through which the plasma {beta} changes from >1 to <1 with altitude. The crossing of this magnetic transition zone requires the magnetic field to adopt a serpentine shape also known as the sea-serpent topology. In the frame of the resistive flux-emergence model, the rising of the magnetic flux is believed to be dynamically driven by a succession of magnetic reconnections which are commonly observed in emerging flux regions as Ellerman bombs. Using a data-driven, three-dimensional (3D) magnetohydrodynamic numerical simulation of flux emergence occurring in active region 10191 on 2002 November 16-17, we study the development of 3D electric current sheets. We show that these currents buildup along the 3D serpentine magnetic-field structure as a result of photospheric diverging horizontal line-tied motions that emulate the observed photospheric evolution. We observe that reconnection can not only develop following a pinching evolution of the serpentine field line, as usually assumed in two-dimensional geometry, but can also result from 3D shearing deformation of the magnetic structure. In addition, we report for the first time on the observation in the UV domain with the Transition Region and Coronal Explorer (TRACE) of extremely transient loop-like features, appearing within the emerging flux domain, which link several Ellermam bombs with one another. We argue that these loop transients can be explained as a consequence of the currents that build up along the serpentine magnetic field.

  9. Depletion Analysis of Modular High Temperature Gas-cooled Reactor Loaded with LEU/Thorium Fuel

    SciTech Connect

    Sonat Sen; Gilles Youinou

    2013-02-01

    Thorium based fuel has been considered as an option to uranium-based fuel, based on considerations of resource utilization (Thorium is more widely available when compared to Uranium). The fertile isotope of Thorium (Th-232) can be converted to fissile isotope U-233 by neutron capture during the operation of a suitable nuclear reactor such as High Temperature Gas-cooled Reactor (HTGR). However, the fertile Thorium needs a fissile supporter to start and maintain the conversion process such as U-235 or Pu-239. This report presents the results of a study that analyzed the thorium utilization in a prismatic HTGR, namely Modular High Temperature Gas-Cooled Reactor (MHTGR) that was designed by General Atomics (GA). The collected for the modeling of this design come from Chapter 4 of MHTGR Preliminary Safety Information Document that GA sent to Department of Energy (DOE) on 1995. Both full core and unit cell models were used to perform this analysis using SCALE 6.1 and Serpent 1.1.18. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were set to match the spectral index between unit cell and full core domains. It was found that for the purposes of this study an adjusted unit cell model is adequate. Discharge isotopics and one-group cross-sections were delivered to the transmutation analysis team. This report provides documentation for these calculations

  10. Cross-Cultural Astronomy in Informal Education Settings - Collaboration with Integrity

    NASA Astrophysics Data System (ADS)

    Maryboy, Nancy; Hawkins, I.; Begay, D.; Sakimoto, P.

    2008-05-01

    The richness of astronomical knowledge and traditions from diverse cultures can engage participants of all ages and backgrounds. We will present astronomy-focused programs for museums, planetariums, and community centers designed to enhance participation of underserved populations in celebrating the International Year of Astronomy (IYA) in 2009. We will share examples of how the indigenous astronomies from the Southwestern US and Mesoamerica can be juxtaposed with Western astronomy to enhance education efforts and understanding for all audiences. In these examples, the traditional knowledge has been highlighted and incorporated into the realm of innovative and unique multimedia resources that engage students and the public, and which often ignite a deeper and more authentic interest in western astronomy and astrophysics. We will discuss approaches to displaying the Navajo sky in a digital planetarium in a manner that is true to the Navajo worldview and that also presents images and information from Western astronomy. We will share multi-media resources that highlight the importance of solar alignments in architecture and in landscape within the context of the seasons. We will also discuss how we are exploring ways to protect the intellectual property rights of indigenous sky knowledge while making aspects of it available to the general public. Our collaboration upholds the integrity of both Western and Indigenous astronomy knowledge and research protocols, and honors indigenous languages. We will discuss collaborative and relationship-based evaluation strategies emerging from the above efforts and from a new effort, Cosmic Serpent, a professional development program to increase the capacity of museum practitioners to bridge indigenous and western science learning in informal settings. We will provide links and information to access products and programs to engage all audiences in the wonder, complexity, and beauty of our Universe. We acknowledge the generous support of NASA/SMD and NSF DRL/ISE.

  11. Transcriptomic analysis of the venom gland of the red-headed krait (Bungarus flaviceps) using expressed sequence tags

    PubMed Central

    2010-01-01

    Background The Red-headed krait (Bungarus flaviceps, Squamata: Serpentes: Elapidae) is a medically important venomous snake that inhabits South-East Asia. Although the venoms of most species of the snake genus Bungarus have been well characterized, a detailed compositional analysis of B. flaviceps is currently lacking. Results Here, we have sequenced 845 expressed sequence tags (ESTs) from the venom gland of a B. flaviceps. Of the transcripts, 74.8% were putative toxins; 20.6% were cellular; and 4.6% were unknown. The main venom protein families identified were three-finger toxins (3FTxs), Kunitz-type serine protease inhibitors (including chain B of ?-bungarotoxin), phospholipase A2 (including chain A of ?-bungarotoxin), natriuretic peptide (NP), CRISPs, and C-type lectin. Conclusion The 3FTxs were found to be the major component of the venom (39%). We found eight groups of unique 3FTxs and most of them were different from the well-characterized 3FTxs. We found three groups of Kunitz-type serine protease inhibitors (SPIs); one group was comparable to the classical SPIs and the other two groups to chain B of ?-bungarotoxins (with or without the extra cysteine) based on sequence identity. The latter group may be functional equivalents of dendrotoxins in Bungarus venoms. The natriuretic peptide (NP) found is the first NP for any Asian elapid, and distantly related to Australian elapid NPs. Our study identifies several unique toxins in B. flaviceps venom, which may help in understanding the evolution of venom toxins and the pathophysiological symptoms induced after envenomation. PMID:20350308

  12. [Relationships between venomous function and innate immune function].

    PubMed

    Goyffon, Max; Saul, Frederick; Faure, Grazyna

    2015-01-01

    Venomous function is investigated in relation to innate immune function in two cases selected from scorpion venom and serpent venom. In the first case, structural analysis of scorpion toxins and defensins reveals a close interrelation between both functions (toxic and innate immune system function). In the second case, structural and functional studies of natural inhibitors of toxic snake venom phospholipases A2 reveal homology with components of the innate immune system, leading to a similar conclusion. Although there is a clear functional distinction between neurotoxins, which act by targeting membrane ion channels, and the circulating defensins which protect the organism from pathogens, the scorpion short toxins and defensins share a common protein folding scaffold with a conserved cysteine-stabilized alpha-beta motif of three disulfide bridges linking a short alpha helix and an antiparallel beta sheet. Genomic analysis suggests that these proteins share a common ancestor (long venom toxins were separated from an early gene family which gave rise to separate short toxin and defensin families). Furthermore, a scorpion toxin has been experimentally synthetized from an insect defensin, and an antibacterial scorpion peptide, androctonin (whose structure is similar to that of a cone snail venom toxin), was shown to have a similar high affinity for the postsynaptic acetylcholine receptor of Torpedo sp. Natural inhibitors of phospholipase A2 found in the blood of snakes are associated with the resistance of venomous snakes to their own highly neurotoxic venom proteins. Three classes of phospholipases A2 inhibitors (PLI-α, PLI-β, PLI-γ) have been identified. These inhibitors display diverse structural motifs related to innate immune proteins including carbohydrate recognition domains (CRD), leucine rich repeat domains (found in Toll-like receptors) and three finger domains, which clearly differentiate them from components of the adaptive immune system. Thus, in structure, function and phylogeny, venomous function in both vertebrates and invertebrates are clearly interrelated with innate immune function. PMID:26820828

  13. Sun-Earth Day 2005: Ancient Observatories: Timeless Knowledge

    NASA Astrophysics Data System (ADS)

    Thieman, J. R.; Cline, T.; Lewis, E.; Hawkins, I.; Odenwald, S.; Mayo, L.

    2005-05-01

    The NASA Sun-Earth Connection Education Forum (SECEF) annually promotes an event called Sun-Earth Day. For Sun-Earth Day 2005 SECEF has selected a theme called "Ancient Observatories: Timeless Knowledge. This year's Sun-Earth Day theme is your ticket to a fascinating journey through time as we explore centuries of sun watching by a great variety of cultures. From ancient solar motion tracking to modern solar activity monitoring the Sun has always occupied an important spot in mankind's quest to understand the Universe. Sun-Earth Day events usually are centered on the spring equinox around March 21, but this year there has already been a webcast from the San Francisco Exploratorium and the Native American ruins at Chaco Canyon, New Mexico on the day of winter solstice 2004. There will be another webcast on March 20 live from Chichen Itza, Mexico highlighting the solar alignment that makes a serpent appear on one of the ancient pyramids. The website http://sunearthday.nasa.gov has been developed to provide the necessary resources and opportunities for participation by scientists and educators in giving school or general public programs about Sun-Earth Day. The goal is to involve as much of the student population and the public in this event as possible and to help them understand the importance of the Sun for ancient and modern peoples. Through engaging activities available on the website, classrooms and museums can create their own event or participate in one of the opportunities we make available. Scientists, educators, amateur astronomers, and museums are invited to register on the website to receive a free packet of materials about Sun-Earth Day for use in making presentations or programs about the event. Past and future Sun-Earth Days will be discussed as well.

  14. Detecting Mantle Anisotropy with Marine CSEM Sounding

    NASA Astrophysics Data System (ADS)

    Constable, S.; Key, K. W.; Behrens, J. P.; MacGregor, L.; Evans, R. L.

    2010-12-01

    We can detect transverse electrical anisotropy in the oceanic crust and upper mantle using circular transmitter tows around a pair of highly sensitive controlled-source electromagnetic (CSEM) receivers. Our long-wire electromagnetic (LEM) receivers, equipped with 100-200 m antennas, improve signal to noise by about an order of magnitude over standard EM receivers using 8-10 m antennas. LEMs work well in deep water where voltage noise from electrodes and amplifiers dominates, and electric field noise from magnetotelluric signals and water motion is low. When combined with SUESI, our marine EM transmitter, which emits 300 amps across a 250 m antenna, noise floors of 10-17~V/Am2 may be obtained at 2-4 Hz over 40-minute stacks. Towing a transmitter in a 30 km circle around an orthogonal pair of LEMs samples propagation though the crust and upper mantle in all horizontal directions. This purely azimuthal geometry generates linearly polarized data for an isotropic earth, but in the presence of anisotropy the minor axis of the polarization ellipse develops a characteristic clover-leaf pattern when plotted against source-receiver direction, and the major axis becomes elongated. We have conducted such experiments on 40 Ma lithosphere offshore California (the APPLE experiment), and 24 Ma lithosphere as it subducts into the Nicaraguan trench (part of the SERPENT expedition). Both regions produce remarkably similar results, with increased conductivity in the fossil ridge-parallel directions, which we interpret to be caused by serpentinized mantle-penetrating faults. This pattern of anisotropy is modified in the outer rise of the trench, as the lithosphere bends and shallower (crustal) fractures develop.

  15. Identification of fat-cell enhancer regions in Drosophila melanogaster.

    PubMed

    Miller, J M; Oligino, T; Pazdera, M; López, A J; Hoshizaki, D K

    2002-02-01

    The insect fat body is a dynamic tissue involved in maintaining homeostasis. It functions not only in energy storage and intermediary metabolism but also in detoxification, communication and the immune response. Some of these functions are confined to distinct groups of fat body cells. In Drosophila melanogaster, discrete precursor-cell clusters populate the fat body [Hoshizaki, D.K., Blackburn, T., Price, C., Ghosh, M., Miles, K., Ragucci, M. and Sweis, R. (1994) Embryonic fat-cell lineage in Drosophila melanogaster. Development 120: 2489-2499; Hoshizaki, D.K., Lunz, R., Ghosh, M. and Johnson, W. (1995) Identification of fat-cell enhancer activity in Drosophila melanogaster using P-element enhancer traps. Genome 38: 497-506; Riechmann, V., Rehorn, K.P., Reuter, R. and Leptin, M. (1998) The genetic control of the distinction between fat body and gonadal mesoderm in Drosophila. Development 125: 713-723]. Whether these clusters populate defined morphological regions or whether they represent the precursors to functionally similar groups of fat-body cells has not been formally demonstrated. We have identified a 2.1 kb enhancer region from serpent (srp), a GATA transcription factor gene that is sufficient to induce fat-cell formation. This enhancer region drives expression in specific groups of precursor-cell clusters, which we show give rise to defined regions of the mature embryonic fat body. We present evidence that srp expression in different precursor fat cells is controlled by independent cis-acting regulatory regions, and we have tested the role of trans-acting factors in the specification of some of these cells. We suggest that the different positional cues regulating srp expression, and therefore general fat-cell specification, might also be involved in the functional specialization of fat cells. This may be a common mechanism in insects to explain the origin of biochemically distinct regions of the larval/adult fat body. PMID:11841504

  16. Failure to restore vision after optic nerve regeneration in reptiles: interspecies variation in response to axotomy.

    PubMed

    Dunlop, Sarah A; Tee, Lisa B G; Stirling, R Victoria; Taylor, Andrew L; Runham, Phil B; Barber, Andy B; Kuchling, Gerald; Rodger, Jenny; Roberts, J Dale; Harvey, Alan R; Beazley, Lyn D

    2004-10-18

    Optic nerve regeneration within the reptiles is variable. In a snake, Viper aspis, and the lizard Gallotia galloti, regeneration is slow, although some retinal ganglion cell (RGC) axons eventually reach the visual centers (Rio et al. [1989] Brain Res 479:151-156; Lang et al. [1998] Glia 23:61-74). By contrast, in a lizard, Ctenophorus ornatus, numerous RGC axons regenerate rapidly to the visual centers, but unless animals are stimulated visually, the regenerated projection lacks topography and animals remain blind via the experimental eye (Beazley et al. [2003] J. Neurotrauma 20:1263-1269). V. aspis, G. galloti, and C. ornatus belong respectively to the Serpentes, Lacertidae, and Agamidae within the Eureptilia, the major modern group of living reptiles comprising the Squamata (snakes, lizards, and geckos) and the Crocodyllia. Here we have extended the findings on Eureptilia to include two geckos (Gekkonidae), Cehyra variegata and Nephrurus stellatus. We also examined a turtle, Chelodina oblonga, the Testudines being the sole surviving representatives of the Parareptilia, the more ancient reptilian group. In all three species, visually elicited behavioral responses were absent throughout regeneration, a result supported electrophysiologically; axonal tracing revealed that only a small proportion of RGC axons crossed the lesion and none entered the contralateral optic tract. RGC axons failed to reach the chiasm in C. oblonga, and in G. variegata, and N. stellatus RGC axons entered the opposite optic nerve; a limited ipsilateral projection was seen in G. variegata. Our results support a heterogeneous response to axotomy within the reptiles, each of which is nevertheless dysfunctional. PMID:15368531

  17. Evolution of the mitochondrial genome in snakes: Gene rearrangements and phylogenetic relationships

    PubMed Central

    Yan, Jie; Li, Hongdan; Zhou, Kaiya

    2008-01-01

    Background Snakes as a major reptile group display a variety of morphological characteristics pertaining to their diverse behaviours. Despite abundant analyses of morphological characters, molecular studies using mitochondrial and nuclear genes are limited. As a result, the phylogeny of snakes remains controversial. Previous studies on mitochondrial genomes of snakes have demonstrated duplication of the control region and translocation of trnL to be two notable features of the alethinophidian (all serpents except blindsnakes and threadsnakes) mtDNAs. Our purpose is to further investigate the gene organizations, evolution of the snake mitochondrial genome, and phylogenetic relationships among several major snake families. Results The mitochondrial genomes were sequenced for four taxa representing four different families, and each had a different gene arrangement. Comparative analyses with other snake mitochondrial genomes allowed us to summarize six types of mitochondrial gene arrangement in snakes. Phylogenetic reconstruction with commonly used methods of phylogenetic inference (BI, ML, MP, NJ) arrived at a similar topology, which was used to reconstruct the evolution of mitochondrial gene arrangements in snakes. Conclusion The phylogenetic relationships among the major families of snakes are in accordance with the mitochondrial genomes in terms of gene arrangements. The gene arrangement in Ramphotyphlops braminus mtDNA is inferred to be ancestral for snakes. After the divergence of the early Ramphotyphlops lineage, three types of rearrangements occurred. These changes involve translocations within the IQM tRNA gene cluster and the duplication of the CR. All phylogenetic methods support the placement of Enhydris plumbea outside of the (Colubridae + Elapidae) cluster, providing mitochondrial genomic evidence for the familial rank of Homalopsidae. PMID:19038056

  18. Release of Oceanic Intraplate Magmatic CO2, Carbonatization, and Decarbonatization Reactions in the Lower Oceanic Lithosphere and Subducting Slabs and Associated Intraplate and Intraslab Earthquakes

    NASA Astrophysics Data System (ADS)

    Kirby, S. H.

    2011-12-01

    Release of free CO2 from ascending mafic magmas is thought to be important for intraplate magmatic systems under the ocean basins and gives insight into the cause of deep mantle earthquakes such as those that occur under the Island of Hawai'i at depths of 20 to 60 km via pore-pressure effects. Moreover, this hypothesis is consistent with the occurrence of CO2-filled inclusions along healed fractures in mantle xenoliths in Hawai'ian in ultramafic xenoliths of presumed mantle or deep-crustal origin. The positive pressure effect on CO2 solubility in mafic melts implies that this volatile boils out of such magmas as they ascend and enables fracture and frictional sliding at mantle depths by reducing the effective normal stresses. It is likely that such CO2 is stored along such fractures and faults during the active stage of plume magmatic activity and that during cooling, this CO2 reacts with mantle silicates to form magnesite and dolomite as oceanic lithosphere cools. Such carbonates are much weaker than mantle peridotites (Holyoke and Kronenberg, this session) and are therefore expected to localize strain along such carbonated zones where the oceanic plate is under tectonic stresses. Such conditions are found in the zone of bending near trenches and within subducting slabs where double zones of seismicity are locally present. Localized plastic deformation and viscous heating leading to free CO2 release through decarbonatization and perhaps melting may enable seismogenesis at such depths in mantle lithosphere. This model for the lower zones of double seismic zones where the enabling fluid comes from below the plate from plume magmatic processes (Kirby, 1995; Seno and Yamanaka, 1996) is much more appealing than positing fluid penetration and serpentization downward through the entire oceanic lithosphere from the ocean floor followed by serpentinite dehydration upon subsequent heating during slab descent.

  19. Molecular systematics of new world gopher, bull, and pinesnakes (Pituophis: Colubridae), a transcontinental species complex.

    PubMed

    Rodríguez-Robles, J A; De Jesús-Escobar, J M

    2000-01-01

    Pituophis melanoleucus (gopher, bull, and pinesnakes) is among the most widely distributed polytypic species complexes in North America, with most authors recognizing from a single transcontinental species (the melanoleucus complex, composed of 15 subspecies) to four (monotypic and polytypic) species. We used mitochondrial gene sequences from the two middle American species, P. deppei and P. lineaticollis, and from 13 subspecies from most of the range of the melanoleucus complex to test various phylogenetic hypotheses for Pituophis. Maximum parsimony and maximum likelihood methods identified the same major clades within Pituophis and indicated that two segments of the melanoleucus complex, the lodingi-melanoleucus-mugitus eastern pinesnake clade and the affinis-annectens-bimaris-catenifer-deserticola- sayi-ruthveni-vertebr alis clade from central and western United States and northern Mexico, represent divergent, allopatric lineages with no known intergradation zone. We recognize each of these two groupings as a different species. Our data also indicate that some ruthveni are more closely related to sayi than to other ruthveni. Nonetheless, ruthveni is an allopatric taxon diagnosable from its closest relatives by a combination of morphometric characters, and because it is likely that at least some of these traits are independent and genetically inherited, we interpret this as evidence that ruthveni has attained the status of independent evolutionary lineage, despite the fact that it retains strong genetic affinities with sayi. The endemic Baja Californian gopher snakes (bimaris and vertebralis) are considered by some taxonomists as a different species, P. vertebralis, but we discovered that these serpents belong to two different clades and hence we do not agree with the recognition of P. vertebralis as presently defined. In summary, we believe that three distinct species are included in the melanoleucus complex, Pituophis melanoleucus (sensu stricto), P. catenifer, and P. ruthveni, and that their recognition better represents the evolutionary diversity within this species complex. PMID:10631041

  20. Purification and characterization of islet hormones (insulin, glucagon, pancreatic, polypeptide and somatostatin) from the Burmese python, Python molurus.

    PubMed

    Conlon, J M; Secor, S M; Adrian, T E; Mynarcik, D C; Whittaker, J

    1997-08-29

    Insulin was purified from an extract of the pancreas of the Burmese python, Python molurus (Squamata:Serpentes) and its primary structure established as: A Chain: Gly-Ile-Val-Glu-Gln-Cys-Cys-Glu-Asn-Thr10-Cys-Ser-Leu-Tyr-Glu-Leu- Glu-Asn-Tyr-Cys20-Asn. B-Chain: Ala-Pro-Asn-Gln-His-Leu-Cys-Gly-Ser-His10-Leu-Val-Glu-Ala-Leu-Tyr- Leu-Val-Cys-Gly20-Asp-Arg-Gly-Phe-Tyr-Tyr-Ser-Pro-Arg-Ser30. With the exception of the conservative substitution Phe --> Tyr at position B25, those residues in human insulin that comprise the receptor-binding and those residues involved in dimer and hexamer formation are fully conserved in python insulin. Python insulin was slightly more potent (1.8-fold) than human insulin in inhibiting the binding of [125I-Tyr-A14] insulin to the soluble full-length recombinant human insulin receptor but was slightly less potent (1.5-fold) than human insulin for inhibiting binding to the secreted extracellular domain of the receptor. The primary structure of python glucagon contains only one amino acid substitution (Ser28 --> Asn) compared with turtle/duck glucagon and python somatostatin is identical to that of mammalian somatostatin-14. In contrast, python pancreatic polypeptide (Arg-Ile-Ala-Pro-Val-Phe-Pro-Gly-Lys-Asp10-Glu-Leu-Ala-Lys-Phe- Tyr20-Thr-Glu-Leu-Gln-Gln-Tyr-Leu-Asn-Ser-Ile30-Asn-Arg-Pro-Arg -Phe.NH2) contains only 35 instead of the customary 36 residues and the amino acid sequence of this peptide has been poorly conserved between reptiles and birds (18 substitutions compared with alligator and 20 substitutions compared with chicken). PMID:9350978

  1. Ophiolite suture in Central Anatolia: New insights from the Sivas Basin (Turkey)

    NASA Astrophysics Data System (ADS)

    Legeay, Etienne; Ringenbach, Jean-Claude; Mohn, Geoffroy; Kergaravat, Charlie; Callot, Jean-Paul

    2015-04-01

    The closure of the Neotethys is classically associated with the obduction of ophiolitic rocks, defining successive suture zones. Theses Alpine-Himalayan ophiolites reflect a complex and still poorly understood paleogeographic framework. In Turkey, various types of ophiolite have been described, involving supra subduction zone and ophiolitic melanges as well. Hence reconstructions of the Anatolian continent assumed the amalgamation of one or more continental fragments during the Mesozoic-Early Cenozoic time. The Sivas Basin is located in a key position at the junction of three crustal domains: the Pontides to the North, the Anatolide - Tauride platforms to the South, and the Central Anatolian Crystalline Complex to the West. These blocks are separated to the North by the Izmir-Ankara-Erzican suture zone (IAESZ), and by the Inner Tauride suture zone (ITSZ) to the South. Ophiolitic outcrops are common in this area, mainly on the basin borders, and sometimes within the central part. These green rocks have been previously related to the ophiolitic melange from the IAESZ in Northern part and to the ITSZ for the southern parts. Recent fieldwork on the southern edge of the Sivas Basin allows a proper description of the ophiolitic complex, including from bottom to top: (1) a large volume of intensely serpentinized peridotites, strongly veined with chrysotile, with minor gabbroic intrusions; (2) upward, serpentinized mantle rocks affected by a cataclastic deformation associated with tectonic breccias and ophicalcites ; and eventually, (3) on the top of the mantle, silicates deposits similar to radiolarian cherts cover by sedimentary breccias with mantle clasts. New geochemical analysis and subsurface data confirm the existence of a southward obducted slice of ophiolite over more than 100km from North to South, forming the basement of the Sivas Basin since the Campanian. This southward obduction related to the IAESZ appears similar to slow spreading ridge or hyper-extended domains derived ophiolites. We interpret the parent body as related to the exhumation of mantle rocks along low angle detachment faults either during the rifting or the oceanic accretion. The peridotites record a high serpentization degree, increasing toward the surface. Outcropping of the mantle rocks at the sea floor is responsible for the reworking of materials as tectonosedimentary breccias (ophicalcites). The emplacement of the gabbro will be constrained by U-Pb zircon geochronology.

  2. Profiling the venom gland transcriptomes of Costa Rican snakes by 454 pyrosequencing

    PubMed Central

    2011-01-01

    Background A long term research goal of venomics, of applied importance for improving current antivenom therapy, but also for drug discovery, is to understand the pharmacological potential of venoms. Individually or combined, proteomic and transcriptomic studies have demonstrated their feasibility to explore in depth the molecular diversity of venoms. In the absence of genome sequence, transcriptomes represent also valuable searchable databases for proteomic projects. Results The venom gland transcriptomes of 8 Costa Rican taxa from 5 genera (Crotalus, Bothrops, Atropoides, Cerrophidion, and Bothriechis) of pitvipers were investigated using high-throughput 454 pyrosequencing. 100,394 out of 330,010 masked reads produced significant hits in the available databases. 5.165,220 nucleotides (8.27%) were masked by RepeatMasker, the vast majority of which corresponding to class I (retroelements) and class II (DNA transposons) mobile elements. BLAST hits included 79,991 matches to entries of the taxonomic suborder Serpentes, of which 62,433 displayed similarity to documented venom proteins. Strong discrepancies between the transcriptome-computed and the proteome-gathered toxin compositions were obvious at first sight. Although the reasons underlaying this discrepancy are elusive, since no clear trend within or between species is apparent, the data indicate that individual mRNA species may be translationally controlled in a species-dependent manner. The minimum number of genes from each toxin family transcribed into the venom gland transcriptome of each species was calculated from multiple alignments of reads matched to a full-length reference sequence of each toxin family. Reads encoding ORF regions of Kazal-type inhibitor-like proteins were uniquely found in Bothriechis schlegelii and B. lateralis transcriptomes, suggesting a genus-specific recruitment event during the early-Middle Miocene. A transcriptome-based cladogram supports the large divergence between A. mexicanus and A. picadoi, and a closer kinship between A. mexicanus and C. godmani. Conclusions Our comparative next-generation sequencing (NGS) analysis reveals taxon-specific trends governing the formulation of the venom arsenal. Knowledge of the venom proteome provides hints on the translation efficiency of toxin-coding transcripts, contributing thereby to a more accurate interpretation of the transcriptome. The application of NGS to the analysis of snake venom transcriptomes, may represent the tool for opening the door to systems venomics. PMID:21605378

  3. Deterministic Modeling of the High Temperature Test Reactor

    SciTech Connect

    Ortensi, J.; Cogliati, J. J.; Pope, M. A.; Ferrer, R. M.; Ougouag, A. M.

    2010-06-01

    Idaho National Laboratory (INL) is tasked with the development of reactor physics analysis capability of the Next Generation Nuclear Power (NGNP) project. In order to examine INL’s current prismatic reactor deterministic analysis tools, the project is conducting a benchmark exercise based on modeling the High Temperature Test Reactor (HTTR). This exercise entails the development of a model for the initial criticality, a 19 column thin annular core, and the fully loaded core critical condition with 30 columns. Special emphasis is devoted to the annular core modeling, which shares more characteristics with the NGNP base design. The DRAGON code is used in this study because it offers significant ease and versatility in modeling prismatic designs. Despite some geometric limitations, the code performs quite well compared to other lattice physics codes. DRAGON can generate transport solutions via collision probability (CP), method of characteristics (MOC), and discrete ordinates (Sn). A fine group cross section library based on the SHEM 281 energy structure is used in the DRAGON calculations. HEXPEDITE is the hexagonal z full core solver used in this study and is based on the Green’s Function solution of the transverse integrated equations. In addition, two Monte Carlo (MC) based codes, MCNP5 and PSG2/SERPENT, provide benchmarking capability for the DRAGON and the nodal diffusion solver codes. The results from this study show a consistent bias of 2–3% for the core multiplication factor. This systematic error has also been observed in other HTTR benchmark efforts and is well documented in the literature. The ENDF/B VII graphite and U235 cross sections appear to be the main source of the error. The isothermal temperature coefficients calculated with the fully loaded core configuration agree well with other benchmark participants but are 40% higher than the experimental values. This discrepancy with the measurement stems from the fact that during the experiments the control rods were adjusted to maintain criticality, whereas in the model, the rod positions were fixed. In addition, this work includes a brief study of a cross section generation approach that seeks to decouple the domain in order to account for neighbor effects. This spectral interpenetration is a dominant effect in annular HTR physics. This analysis methodology should be further explored in order to reduce the error that is systematically propagated in the traditional generation of cross sections.

  4. Hubble Unveils Colorful and Turbulent Star-Birth Region on 100,000th Orbit Milestone

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for orientation annotation

    In commemoration of NASA's Hubble Space Telescope completing its 100,000th orbit in its 18th year of exploration and discovery, scientists at the Space Telescope Science Institute in Baltimore, Md., have aimed Hubble totake a snapshot of a dazzling region of celestial birth and renewal.

    Hubble peered into a small portion of the nebula near the star cluster NGC 2074 (upper, left). The region is a firestorm of raw stellar creation, perhaps triggered by a nearby supernova explosion. It lies about 170,000 light-years away near the Tarantula nebula, one of the most active star-forming regions in our Local Group of galaxies.

    The three-dimensional-looking image reveals dramatic ridges and valleys of dust, serpent-head 'pillars of creation,' and gaseous filaments glowing fiercely under torrential ultraviolet radiation. The region is on the edge of a dark molecular cloud that is an incubator for the birth of new stars.

    The high-energy radiation blazing out from clusters of hot young stars already born in NGC 2074 is sculpting the wall of the nebula by slowly eroding it away. Another young cluster may be hidden beneath a circle of brilliant blue gas at center, bottom.

    In this approximately 100-light-year-wide fantasy-like landscape, dark towers of dust rise above a glowing wall of gases on the surface of the molecular cloud. The seahorse-shaped pillar at lower, right is approximately 20 light-years long, roughly four times the distance between our Sun and the nearest star, Alpha Centauri.

    The region is in the Large Magellanic Cloud (LMC), a satellite of our Milky Way galaxy. It is a fascinating laboratory for observing star-formation regions and their evolution. Dwarf galaxies like the LMC are considered to be the primitive building blocks of larger galaxies.

    This representative color image was taken on August 10, 2008, with Hubble's Wide Field Planetary Camera 2. Red shows emission from sulfur atoms, green from glowing hydrogen, and blue from glowing oxygen.

  5. Results for Phase I of the IAEA Coordinated Research Program on HTGR Uncertainties

    SciTech Connect

    Strydom, Gerhard; Bostelmann, Friederike; Yoon, Su Jong

    2015-01-01

    The quantification of uncertainties in design and safety analysis of reactors is today not only broadly accepted, but in many cases became the preferred way to replace traditional conservative analysis for safety and licensing analysis. The use of a more fundamental methodology is also consistent with the reliable high fidelity physics models and robust, efficient, and accurate codes available today. To facilitate uncertainty analysis applications a comprehensive approach and methodology must be developed and applied. High Temperature Gas-cooled Reactors (HTGR) has its own peculiarities, coated particle design, large graphite quantities, different materials and high temperatures that also require other simulation requirements. The IAEA has therefore launched a Coordinated Research Project (CRP) on the HTGR Uncertainty Analysis in Modeling (UAM) in 2013 to study uncertainty propagation specifically in the HTGR analysis chain. Two benchmark problems are defined, with the prismatic design represented by the General Atomics (GA) MHTGR-350 and a 250 MW modular pebble bed design similar to the HTR-PM (INET, China). This report summarizes the contributions of the HTGR Methods Simulation group at Idaho National Laboratory (INL) up to this point of the CRP. The activities at INL have been focused so far on creating the problem specifications for the prismatic design, as well as providing reference solutions for the exercises defined for Phase I. An overview is provided of the HTGR UAM objectives and scope, and the detailed specifications for Exercises I-1, I-2, I-3 and I-4 are also included here for completeness. The main focus of the report is the compilation and discussion of reference results for Phase I (i.e. for input parameters at their nominal or best-estimate values), which is defined as the first step of the uncertainty quantification process. These reference results can be used by other CRP participants for comparison with other codes or their own reference results. The status on the Monte Carlo modeling of the experimental VHTRC facility is also discussed. Reference results were obtained for the neutronics stand-alone cases (Ex. I-1 and Ex. I-2) using the (relatively new) Monte Carlo code Serpent, and comparisons were performed with the more established Monte Carlo codes MCNP and KENO-VI. For the thermal-fluids stand-alone cases (Ex. I-3 and I-4) the commercial CFD code CFX was utilized to obtain reference results that can be compared with lower fidelity tools.

  6. The Thousand-Ruby Galaxy

    NASA Astrophysics Data System (ADS)

    2008-09-01

    ESO's Wide Field Imager has captured the intricate swirls of the spiral galaxy Messier 83, a smaller look-alike of our own Milky Way. Shining with the light of billions of stars and the ruby red glow of hydrogen gas, it is a beautiful example of a barred spiral galaxy, whose shape has led to it being nicknamed the Southern Pinwheel. Messier 83, M83 ESO PR Photo 25/08 Spiral Galaxy Messier 83 This dramatic image of the galaxy Messier 83 was captured by the Wide Field Imager at ESO's La Silla Observatory, located high in the dry desert mountains of the Chilean Atacama Desert. Messier 83 lies roughly 15 million light-years away towards the huge southern constellation of Hydra (the sea serpent). It stretches over 40 000 light-years, making it roughly 2.5 times smaller than our own Milky Way. However, in some respects, Messier 83 is quite similar to our own galaxy. Both the Milky Way and Messier 83 possess a bar across their galactic nucleus, the dense spherical conglomeration of stars seen at the centre of the galaxies. This very detailed image shows the spiral arms of Messier 83 adorned by countless bright flourishes of ruby red light. These are in fact huge clouds of glowing hydrogen gas. Ultraviolet radiation from newly born, massive stars is ionising the gas in these clouds, causing the great regions of hydrogen to glow red. These star forming regions are contrasted dramatically in this image against the ethereal glow of older yellow stars near the galaxy's central hub. The image also shows the delicate tracery of dark and winding dust streams weaving throughout the arms of the galaxy. Messier 83 was discovered by the French astronomer Nicolas Louis de Lacaille in the mid 18th century. Decades later it was listed in the famous catalogue of deep sky objects compiled by another French astronomer and famous comet hunter, Charles Messier. Recent observations of this enigmatic galaxy in ultraviolet light and radio waves have shown that even its outer desolate regions (farther out than those seen in this image) are populated with baby stars. X-ray observations of the heart of Messier 83 have shown that its centre is a hive of vigorous star formation, held deep within a cloud of superheated gas, with temperatures of 7 million degrees Celsius. Messier 83 is also one of the most prolific producers of supernovae, that is, exploding stars: this is one of the two galaxies, which had 6 supernovae in the past 100 years. One of these, SN 1957D was observable for 30 years! The Wide Field Imager (WFI) is a specialised astronomical camera attached to the 2.2-metre Max-Planck Society/ESO telescope, sited at the La Silla observatory in Chile. Located nearly 2400 m above sea level, atop the mountains of the Atacama Desert, ESO's La Silla enjoys some of the clearest and darkest skies on the whole planet, making the site ideally suited for studying the farthest depths of the Universe. To make this image, the WFI stared at M83 for roughly 100 minutes through a series of specialist filters, allowing the faint detail of the galaxy to reveal itself. The brighter stars in the foreground are stars in our own galaxy, whilst behind M83 the darkness is peppered with the faint smudges of distant galaxies.

  7. How to Steal a Million Stars?

    NASA Astrophysics Data System (ADS)

    2006-02-01

    Based on observations with ESO's Very Large Telescope, a team of Italian astronomers reports [1] that the stellar cluster Messier 12 must have lost to our Milky Way galaxy close to one million low-mass stars. ESO PR Photo 04a/06 ESO PR Photo 04a/06 The Central Part of Messier 12 "In the solar neighbourhood and in most stellar clusters, the least massive stars are the most common, and by far", said Guido De Marchi (ESA), lead author of the study. "Our observations with ESO's VLT show this is not the case for Messier 12." The team, which also includes Luigi Pulone and Francesco Paresce (INAF, Italy), measured the brightness and colours of more than 16,000 stars within the globular cluster Messier 12 [2] with the FORS1 multi-mode instrument attached to one of the Unit Telescopes of ESO's VLT at Cerro Paranal (Chile). The astronomers could study stars that are 40 million times fainter than what the unaided eye can see (magnitude 25). Located at a distance of 23,000 light years in the constellation Ophiuchus (The Serpent-holder), Messier 12 got its name by being the 12th entry in the catalogue of nebulous objects compiled in 1774 by French astronomer and comet chaser Charles Messier. It is also known to astronomers as NGC 6218 and contains about 200,000 stars, most of them having a mass between 20 and 80 percent of the mass of the Sun. "It is however clear that Messier 12 is surprisingly devoid of low-mass stars", said De Marchi. "For each solar-like star, we would expect roughly four times as many stars with half that mass. Our VLT observations only show an equal number of stars of different masses." ESO PR Photo 04b/06 ESO PR Photo 04b/06 Loosing Stars in the Milky Way Globular clusters move in extended elliptical orbits that periodically take them through the densely populated regions of our Galaxy, the plane, then high above and below, in the 'halo'. When venturing too close to the innermost and denser regions of the Milky Way, the 'bulge', a globular cluster can be perturbed, the smallest stars being ripped away. "We estimate that Messier 12 lost four times as many stars as it still has", said Francesco Paresce. "That is, roughly one million stars must have been ejected into the halo of our Milky Way." The total remaining lifetime of Messier 12 is predicted to be about 4.5 billion years, i.e. about a third of its present age. This is very short compared to the typical expected globular cluster's lifetime, which is about 20 billion years. The same team of astronomers had found in 1999, another example of a globular cluster that lost a large fraction of its original content (see ESO PR 04/99). The scientists hope to discover and study many more clusters like these, since catching clusters while being disrupted should clarify the dynamics of the process that shaped the halo of our home galaxy, the Milky Way. High resolution images and their captions are available on this page. A press release on this is also issued by INAF in Italian and is available at www.inaf.it/comunicati_stampa/cs070206/Inaf-04-06.html.

  8. Broken formations, melanges and olistostromes in Puerto Plata area (Northern Dominican Republic) as a record of subduction and collisional processes between the Caribbean and North-American plates

    NASA Astrophysics Data System (ADS)

    Hernaiz Huerta, Pedro Pablo; Valera Fernando, Pérez; de Los Santos Manuel, Abad; Jacques, Monthel; de Neira Alberto, Díaz

    2010-05-01

    The Northern Cordillera of the Dominican Republic records the (oblique) subduction and collisional processes occurred between the Caribbean and North-American plates during Upper Cretaceous to Lower Paleogene times. The boundary between these two plates can be traced within this range disrupted by an Upper Paleogene to present intense left-lateral strike-slip tectonism, onset after collision. In the western part of the range this boundary might be defined by the Camu fault. In the coastal area of Puerto Plata, located on the northern block of the Camu fault, basement rocks belonging to the subducting plate (the Puerto Plata Basement Complex) and several related units probably formed in an accretionary prism, preserve in a large (300 km2) outcrop of chaotic formations presumably formed (and exhumed) during collision. They include from broken formations and tectonic melanges to olistostromes and other coeval sedimentary deposits. The Puerto Plata Basement Complex (PPBC) consists of highly faulted and dismembered blocks formed by discontinuous but sometimes coherent outcrops of serpentinized or massive peridotite, pods of ultramafic cumulates, massive or banded gabbros and Los Caños Fm, a thick sequence of gross bedded volcaniclastic material with interbedded basaltic (sometimes pillowed) or andesitic flows. All these rocks bear low grade metamorphism and lack a general deformation fabric apart from occasional transformation to mylonites due to localized shearing. The PPBC has been interpreted as a fragment of oceanic crust, belonging to the subducting (North-American) slab that has been exhumed as a tectonic melange or a broken complex. The Imbert Fm, of Palaeocene-Eocene age, is formed by a well bedded succession of white very fine grained porcelaneous tuffs, with eventual intercalations of cherts, limestones and marls that, towards the lower part, is interbedded with volcanic-derived graywackes and limolites, and more occasionally, thick beds of conglomerates and debris. These last ones typically incorporate fragments of serpentized peridotites and blocks of the volcanic rocks identified in the PPBC. The Imbert Fm is also internally disrupted and although not a single clear contact can be observed in the field, it is considered to rest unconformably over the complex, so postdating its exhumation. A separate mappable unit of serpentinitic brecchias has recently been identified mainly distributed along the outer limits of the PPBC but also in several scattered outcrops inside it. The unit is dominantly made of fragments and blocks of serpentinized peridotites, embedded in an abundant matrix of the same composition and includes also blocks of Los Caños and Imbert Fm, as well as other exotic blocks of unknown origin. In the southeastern limit of the complex, close to the Camu fault, there is a particular high concentration of exotic blocks derived from metamorphic rocks (greenschists, anfibolites, marbles and even blueschists) not exposed in any neighbouring areas and thus suggesting a deep-sited, subduction-related, feeding. The basal contact of this unit with the rocks of the PPBC is usually faulted and difficult to observe in the field, but cartographic patterns suggest that it is an unconformity. Outcrops of serpentinitic breccias show a wide variety of internal chaotic organization, from pods of tectonic melanges to the most frequent block-in matrix fabric, but most of them also show evidences of sedimentary rework. In the easternmost part of the PPBC, the serpentinitic brecchias are, in turn, the base of an olistostromic complex widely represented in the region, the San Marcos Fm. The olistostrome includes similar exotic blocks than observed in the serpentinitic brecchias and blocks and olistolithes derived from the PPBC but, mainly, from the Imbert Fm. According to the described relationships, the serpentinitic breccias and San Marcos olistostrome are considered partially coeval and laterally equivalent to the Imbert Fm.

  9. Latest climate changes in Romania :tornadoes

    NASA Astrophysics Data System (ADS)

    Pop, Elena

    2014-05-01

    Latest climate changes in Romania :tornadoes As climate change has been considered a research priority in the European Strategy for enduring development , I have done a detailed research with my students of the new climate change that has been going on in Romania for the past decade. More precisely I have studied together with my students the phenomenon of tornadoes that have seriously affected on some occasions some our our country's locations, such as Facaeni, in the county of Ialomita, in August 2002. A quite unusual phenomenon occurred on that location situated at 44.56 degrees northern latitude and at 27.89 degrees eastern longitude, that caused severe damage to the local environment and three persons lost their lives in the process, as well as other thirty people suffering from bad injuries. The magnitude of that strong phenomenon rose on the Fujita scale at level F3 which implied wing gusts between 252-300 km/ hour . A main cause of occurrence of such a severe weather was the difference in temperature of two huge air masses, one of Polar origin, and other coming from tropical latitudes . Their crossroads was on that precise territory of Romania. The duration of the worst part of the tornado path lasted only for two minutes, but the consequences of its passage were colossal : total destruction of 33 households, and other 395 were partially damaged, 1,000 people afflicted by the devastation and 100 acres of acacia tree forest ripped off the ground. The first ever recorded tornado phenomenon in Romania was around 1894-1896, considered at that time " a freak of nature" was seen as a cloud formation abnormality , an uncontrolled force of nature that had a huge impact , and at the same time, it vanished into "thin air " fast. The most affected areas in Romania by tornadoes are the south-eastern planes where the cloud formations can create fast columns of air rotating up to 500 km/hour. The local people compared the cloud funnels created on the planes to "serpents " that eat and spit out roofs, animals, trucks and concrete road poles. I have minutely searched with my students all the data of that tornado, the direction of wind gusts, we have calculated the force of the impact by studying the photos taken on that occasion. I have also done some research on other tornadoes that have taken place In Movilita and Brezoaele the past years. I have studied the increase of the centrifugal force and that of Coriolis in the context of repetition of such dangerous atmospheric phenomena that showed their apparition as ten per year in Romania. Therefore the average Coriolis parameter is 10-4 s-1, for a typical atmospheric speed of 10 m/s (22 mph) the radius is 100 km (62 mi), with a period of about 17 hours. The lowering of the air pressure occurring on such occasions has been one of my concerns as well the the speed of the cloud column rotation. All these phenomena are the effect of the climate change occurring all over our Planet due to pollution. As you can see the devastation produced by such extreme climate lead to spontaneous floods and later desertification on the south-eastern part of our country. References : 1. Craciun, Cristina, Bala, Bogdan, Tornadele din Romania, http://dezechilibrenaturale.blogspot.ro/2013/02/tornadele-din-romania.html 2. Bell, Aurora, Tornadele in Romania, http://vremea.meteoromania.ro/node/33 3. Lemon, R. Leslie, Stan-Sion, Aurora, Soci , Cornel, Corduneanu, Elena, A strong, long -track, Romanian tornado, http://www.sciencedirect.com/science/article/pii/S0169809503000632 Author : Mrs. Elena Pop, Science teacher at "Lucian Blaga" Secondary School, Ocna Mures, Romania

  10. Radium-226 in cattails, Typha latifolia, and bone of muskrat, Ondatra zibethica (L.), from a watershed with uranium tailings near the city of Elliot Lake, Canada.

    PubMed

    Mirka, M A; Clulow, F V; Davé, N K; Lim, T P

    1996-01-01

    Radium-226 concentrations were measured in the main food plants (cattails, Typha latifolia) and bone of adult muskrats (Ondatra zibethica (L.)), taken from a study area near Quirke Lake in the Serpent River drainage basin. This watershed receives drainage containing radionuclides from the U tailings near the City of Elliot Lake, Ontario, Canada. Two control sites (one local, one 130 km distant) were also sampled. Radium-226 levels in cattails varied by plant part and place of collection. Roots sampled in the study area had the highest mean (226)Ra level (1135.0 mBq g(-1)), stems and leaves had 284.2 and 275.9 mBq g(-1), respectively (dry-weight basis, n = 6 in all cases). Local and distant control cattails carried much lower (226)Ra levels (20.2 and 15.2 mBq g(-1) dry weight, respectively, using pooled equal portions of all plant parts, n = 3 in both cases). Muskrats from waters with mean total (226)Ra levels in the period, 1984-1987 greater than 75.0 mBq litre(-1) ('study-high' sites), near U tailings within 10 km of Quirke Lake, had a mean (geometric) bone level of (226)Ra of 344.9 mBq g(-1) (dry-weight basis, n = 36); those from nearby waters, containing < 75.0 mBq litre(-1) of (226)Ra ('study-low' sites), had a mean bone level (80.3 mBq g(-1), n = 9) similar to animals taken in unaffected local control areas 20 km from the tailings (79.1 mBq g(-1), n = 12); animals from the distant control area, near Sudbury, Ontario, had the lowest mean burden (11.5 mBq g(-1), n = 24). Levels were unrelated to age or sex of the animals. Dry-weight based (226)Ra concentration ratios (bone concentration/plant tissue concentration) were calculated to range from 0.3-1.4 in the study-high area to 2.4-6.3 in the local control area. Wet-weight based concentration ratios were about 4.3 times higher. Concentration ratios were similar to values calculated for other species and in general agreement with values calculated for humans. The muskrat is judged to be a useful indicator (biomonitor) of environmental (226)Ra levels as there is a highly significant positive correlation coefficient (r = 0.74) between bone and ambient (water) concentrations of the radionuclide (F79 = 95.04, P < 0.0001) Estimated yearly (226)Ra intake by people eating muskrats was calculated to be below the current allowable level set by Canadian regulatory authorities. PMID:15091452

  11. An update review on Commiphora molmol and related species.

    PubMed

    Tonkal, Abdulkader M D; Morsy, Tosson A

    2008-12-01

    The origins of myrrh and frankincense are traced to the Arabian Peninsula. According to Herodotus (5th century BC): "Arabia is the only country which produces frankincense, myrrh, cassia, and cinnamon.., the trees bearing the frankincense are guarded by winged serpents of small size and various colors." Diodorus Siculus wrote, in the second half of the first century BC, that "all of Arabia exudes a most delicate fragrance; even the seamen passing by Arabia can smell the strong fragrance that gives health and vigor." He also mentioned gold mines so pure that no smelting was necessary. The Magi, carrying myrrh, frankincense, and gold, came from the East: Arabia. The frankincense trade route, with transport by donkeys and later by camel caravans, reached Jerusalem and Egypt from the Dhofar region of what is today Oman, through Yemen, turning north to follow the Red Sea coast. It is likely that the same or similar species of the resin-bearing plants grew across the Red Sea in the area that is now Somalia and Ethiopia, while the collection of the gum resins was initiated in Arabia. Myrrh contributed much in the human welfare. Schistosomiasis was known in ancient Egypt since remote times. Haematuria with urinary bladder disturbances was mentioned in four Papyrus papers dated back to 1950-1900 BC, and Schistosoma ova was detected in a cirrhotic liver of a mummy from 1200 BC (Ruffer, 1910). Also, Fasciola eggs were detected in a mummy (Looss, 1896). Fascioliasis infected over 17 million people worldwide causing marked morbidity and mortality (Haseeb et al., 2002). Schistosomiasis affected over 200 million people in 74 countries and territories worldwide (WHO, 1999) causing several chronic complications. Both were incriminated to predispose or accompanied human hepatitis and predisposed to HCV (Wahib et al., 2006). Most zoonotic helminthes induced immune response (Nutman, 2001) characterized by producing of type 2 cytokines, Ig G1, IgG2, IgE antibodies and eosinophil and mast cell activation (Hoffman et al., 2002). Treatment of fascioliasis required high or drug multiple doses with side effect (Farid et al., 1990). In schistosomiasis, praziquantel (PZQ) in use for > 20 years was faced with low efficacy (Leishout et al., 1998), or with increased resistance (Coles et al., 1986; Watt et al., 1988; Herrera et al., 1994; Ismail et al., 1994; 1999; Tonelli et al., 1995; Stelma et al., 1995; Fallon et al., 1997; Bennett et al., 1997; Boisier et al., 1998; Periera et al., 1998; Kusel and Hagan, 1999; Liang et al., 2000; King et al., 2000; N'Goran et al., 2003; Raso et al., 2004), potentiality of carcinogenicity, genotoxicity (Rosenkranz et al., 1995), mutagenicity (Montero et al., 1993), big dose lethality and enhanced clastogenicity of environmental pollutants (Anwar, 1994). On the other hand, Nomicos (2007) in USA reported that since antiquity, the genus Commiphora is composed of more than 200 species, and exploited as a natural drug to treat pain, skin infections, inflammatory conditions, diarrhea, and periodontal diseases. He added that in more recent history, products derived from C. myrrha and various other species of Commiphora are becoming recognized to possess significant antiseptic, anesthetic, and antitumor properties. Traditional practice and evidence-based research have supported that these properties are directly attributable to terpenoids (especially furanoses-quiterpenes), the active compounds present in myrrh essential oil. Very recently, current studies have focused on applying clinical trial methodologies to validate its use as an antineoplastic, an antiparasitic agent, and as an adjunct in healing wounds. Weeks and Simpson (2007) in USA presented the molecular phylogeny of Commiphora, a predominantly tropical African, arid-adapted tree genus to test the monophyly of its taxonomic sections and to identify clades to help direct future study of this species-rich and geographically widespread taxon. The multiple fossil calibrations of Commiphora phylogeny proved that it is sister to Vietnamese Burse

  12. First Super-Earth Atmosphere Analysed

    NASA Astrophysics Data System (ADS)

    2010-12-01

    The atmosphere around a super-Earth exoplanet has been analysed for the first time by an international team of astronomers using ESO's Very Large Telescope. The planet, which is known as GJ 1214b, was studied as it passed in front of its parent star and some of the starlight passed through the planet's atmosphere. We now know that the atmosphere is either mostly water in the form of steam or is dominated by thick clouds or hazes. The results will appear in the 2 December 2010 issue of the journal Nature. The planet GJ 1214b was confirmed in 2009 using the HARPS instrument on ESO's 3.6-metre telescope in Chile (eso0950) [1]. Initial findings suggested that this planet had an atmosphere, which has now been confirmed and studied in detail by an international team of astronomers, led by Jacob Bean (Harvard-Smithsonian Center for Astrophysics), using the FORS instrument on ESO's Very Large Telescope. "This is the first super-Earth to have its atmosphere analysed. We've reached a real milestone on the road toward characterising these worlds," said Bean. GJ 1214b has a radius of about 2.6 times that of the Earth and is about 6.5 times as massive, putting it squarely into the class of exoplanets known as super-Earths. Its host star lies about 40 light-years from Earth in the constellation of Ophiuchus (the Serpent Bearer). It is a faint star [2], but it is also small, which means that the size of the planet is large compared to the stellar disc, making it relatively easy to study [3]. The planet travels across the disc of its parent star once every 38 hours as it orbits at a distance of only two million kilometres: about seventy times closer than the Earth orbits the Sun. To study the atmosphere, the team observed the light coming from the star as the planet passed in front of it [4]. During these transits, some of the starlight passes through the planet's atmosphere and, depending on the chemical composition and weather on the planet, specific wavelengths of light are absorbed. The team then compared these precise new measurements with what they would expect to see for several possible atmospheric compositions. Before the new observations, astronomers had suggested three possible atmospheres for GJ 1214b. The first was the intriguing possibility that the planet was shrouded by water, which, given the close proximity to the star, would be in the form of steam. The second possibility was that this is a rocky world with an atmosphere consisting mostly of hydrogen, but with high clouds or hazes obscuring the view. The third option was that this exoplanet was like a mini-Neptune, with a small rocky core and a deep hydrogen-rich atmosphere. The new measurements do not show the telltale signs of hydrogen and hence rule out the third option. Therefore, the atmosphere is either rich in steam, or it is blanketed by clouds or hazes, similar to those seen in the atmospheres of Venus and Titan in our Solar System, which hide the signature of hydrogen.. "Although we can't yet say exactly what that atmosphere is made of, it is an exciting step forward to be able to narrow down the options for such a distant world to either steamy or hazy," says Bean. "Follow-up observations in longer wavelength infrared light are now needed to determine which of these atmospheres exists on GJ 1214b." Notes [1] The number of confirmed exoplanets reached 500 on 19 November 2010. Since then, more exoplanets have been confirmed. For the latest count, please visit: http://exoplanet.eu/catalog.php [2] If GJ 1214 were seen at the same distance from us as our Sun, it would appear 300 times fainter. [3] Because the star GJ1214 itself is quite faint - more than 100 times fainter in visible light than the host stars of the two most widely studied hot Jupiter exoplanets - the large collecting area of the Very Large Telescope was critical for acquiring enough signal for these measurements. [4] GJ 1214b's atmospheric composition was studied using the FORS instrument on the Very Large Telescope, which can perform very sensitive spectroscopy of multiple objects in the near-infrared part of the spectrum. FORS was one of the first instruments installed on the Very Large Telescope. More information This research is presented in a paper to appear in Nature on 2 December 2010. The team is composed of Jacob Bean (Harvard-Smithsonian Center for Astrophysics, USA), Eliza Miller-Ricci Kempton (University of California, Santa Cruz, USA) and Derek Homeier (Institute for Astrophysics, Göttingen, Germany). ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and VISTA, the world's largest survey telescope. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".

  13. The Development of WARP - A Framework for Continuous Energy Monte Carlo Neutron Transport in General 3D Geometries on GPUs

    NASA Astrophysics Data System (ADS)

    Bergmann, Ryan

    Graphics processing units, or GPUs, have gradually increased in computational power from the small, job-specific boards of the early 1990s to the programmable powerhouses of today. Compared to more common central processing units, or CPUs, GPUs have a higher aggregate memory bandwidth, much higher floating-point operations per second (FLOPS), and lower energy consumption per FLOP. Because one of the main obstacles in exascale computing is power consumption, many new supercomputing platforms are gaining much of their computational capacity by incorporating GPUs into their compute nodes. Since CPU-optimized parallel algorithms are not directly portable to GPU architectures (or at least not without losing substantial performance), transport codes need to be rewritten to execute efficiently on GPUs. Unless this is done, reactor simulations cannot take full advantage of these new supercomputers. WARP, which can stand for ``Weaving All the Random Particles,'' is a three-dimensional (3D) continuous energy Monte Carlo neutron transport code developed in this work as to efficiently implement a continuous energy Monte Carlo neutron transport algorithm on a GPU. WARP accelerates Monte Carlo simulations while preserving the benefits of using the Monte Carlo Method, namely, very few physical and geometrical simplifications. WARP is able to calculate multiplication factors, flux tallies, and fission source distributions for time-independent problems, and can run in both criticality or fixed source modes. WARP can transport neutrons in unrestricted arrangements of parallelepipeds, hexagonal prisms, cylinders, and spheres. WARP uses an event-based algorithm, but with some important differences. Moving data is expensive, so WARP uses a remapping vector of pointer/index pairs to direct GPU threads to the data they need to access. The remapping vector is sorted by reaction type after every transport iteration using a high-efficiency parallel radix sort, which serves to keep the reaction types as contiguous as possible and removes completed histories from the transport cycle. The sort reduces the amount of divergence in GPU ``thread blocks,'' keeps the SIMD units as full as possible, and eliminates using memory bandwidth to check if a neutron in the batch has been terminated or not. Using a remapping vector means the data access pattern is irregular, but this is mitigated by using large batch sizes where the GPU can effectively eliminate the high cost of irregular global memory access. WARP modifies the standard unionized energy grid implementation to reduce memory traffic. Instead of storing a matrix of pointers indexed by reaction type and energy, WARP stores three matrices. The first contains cross section values, the second contains pointers to angular distributions, and a third contains pointers to energy distributions. This linked list type of layout increases memory usage, but lowers the number of data loads that are needed to determine a reaction by eliminating a pointer load to find a cross section value. Optimized, high-performance GPU code libraries are also used by WARP wherever possible. The CUDA performance primitives (CUDPP) library is used to perform the parallel reductions, sorts and sums, the CURAND library is used to seed the linear congruential random number generators, and the OptiX ray tracing framework is used for geometry representation. OptiX is a highly-optimized library developed by NVIDIA that automatically builds hierarchical acceleration structures around user-input geometry so only surfaces along a ray line need to be queried in ray tracing. WARP also performs material and cell number queries with OptiX by using a point-in-polygon like algorithm. WARP has shown that GPUs are an effective platform for performing Monte Carlo neutron transport with continuous energy cross sections. Currently, WARP is the most detailed and feature-rich program in existence for performing continuous energy Monte Carlo neutron transport in general 3D geometries on GPUs, but compared to production codes like Serpent and MCNP, WARP has limited capabilities. Despite WARP's lack of features, its novel algorithm implementations show that high performance can be achieved on a GPU despite the inherently divergent program flow and sparse data access patterns. WARP is not ready for everyday nuclear reactor calculations, but is a good platform for further development of GPU-accelerated Monte Carlo neutron transport. In it's current state, it may be a useful tool for multiplication factor searches, i.e. determining reactivity coefficients by perturbing material densities or temperatures, since these types of calculations typically do not require many flux tallies. (Abstract shortened by UMI.)

  14. A Vanishing Star Revisited

    NASA Astrophysics Data System (ADS)

    1999-07-01

    VLT Observations of an Unusual Stellar System Reinhold Häfner of the Munich University Observatory (Germany) is a happy astronomer. In 1988, when he was working at a telescope at the ESO La Silla observatory, he came across a strange star that suddenly vanished off the computer screen. He had to wait for more than a decade to get the full explanation of this unusual event. On June 10-11, 1999, he observed the same star with the first VLT 8.2-m Unit Telescope (ANTU) and the FORS1 astronomical instrument at Paranal [1]. With the vast power of this new research facility, he was now able to determine the physical properties of a very strange stellar system in which two planet-size stars orbit each other. One is an exceedingly hot white dwarf star , weighing half as much as the Sun, but only twice as big as the Earth. The other is a much cooler and less massive red dwarf star , one-and-a-half times the size of planet Jupiter. Once every three hours, the hot star disappears behind the other, as seen from the Earth. For a few minutes, the brightness of the system drops by a factor of more than 250 and it "vanishes" from view in telescopes smaller than the VLT. A variable star named NN Serpentis ESO PR Photo 30a/99 ESO PR Photo 30a/99 [Preview - JPEG: 400 x 468 pix - 152k] [Normal - JPEG: 800 x 936 pix - 576k] [High-Res - JPEG: 2304 x 2695 pix - 4.4M] Caption to ESO PR Photo 30a/99 : The sky field around the 17-mag variable stellar system NN Serpentis , as seen in a 5 sec exposure through a V(isual) filter with VLT ANTU and FORS1. It was obtained just before the observation of an eclipse of this unsual object and served to centre the telescope on the corresponding sky position. The field shown here measures 4.5 x 4.5 armin 2 (1365 x 1365 pix 2 ; 0.20 arcsec/pix). The field is somewhat larger than that shown in Photo 30b/99 and has the same orientation to allow comparison: North is about 20° anticlockwise from the top and East is 90° clockwise from that direction. The unsual star in question is designated NN Serpentis , or just NN Ser . As the name indicates, it is located in the constellation of Serpens (The Serpent), about 12° north of the celestial equator. A double letter, here "NN", is used to denote variable stars [2]. It is a rather faint object of magnitude 17, about 25,000 times fainter than what can be perceived with the unaided eye. The distance is about 600 light-years (180 pc). In July 1988, Reinhold Häfner performed observations of NN Ser (at that time still known by its earlier name PG 1550+131 ) with the Danish 1.54-m telescope at La Silla. He was surprised, but also very pleased to discover that it underwent a very deep eclipse every 187 minutes. Within less than 2 minutes, the brightness dropped by a factor of more than 100 (5 magnitudes). During the next 9 minutes, the star completely disappeared from view - it was too faint to be observed with this telescope. It then again reappeared and the entire event was over after just 11 minutes. Why eclipses are so important for stellar studies An eclipse occurs when one of the stars in a binary stellar system moves in front of the other, as seen by the observer. The effect is similar to what happens during a solar eclipse when the Moon moves in front of the Sun. In both cases, the eclipse may be partial or total , depending on whether or not the eclipsed star (or the Sun) is completely hidden from view. The occurence of eclipses in stellar systems, as seen from the Earth, depends on the spatial orientation of the orbital plane and the sizes of the two stars. Two eclipses take place during one orbital revolution, but they may not both be observable. The physical properties of the two stars in a binary system (e.g., the sizes of the stars, the size and shape of the orbit, the distribution of the light on the surfaces of the stars, their temperatures etc.) can be determined from the measured "light-curve" of the system (a plot of brightness vrs. time). The stars are always too close to each other to be seen as anything but a point of light. The light-curve thus describes the way the total brightness of the two stars changes during one orbital revolution, including the variation of the combined light of the two components as they cover each other during the eclipses. Already in 1988, it was concluded that the eclipse observed in NN Ser must be caused by a bright and hot star (a white dwarf ) being hidden by another body, most probably a red dwarf star . Because of the dramatic effect, this object soon became known as the "Vanishing Star" , cf. ESO Press Release 09/88 (8 December 1988). Critical information missing for NN Ser One particularly critical piece of information is needed for a light-curve study to succeed, that is whether the eclipse is "total" or "partial" . If during the eclipse one star is entirely hidden by the other, we only see the light of the star in front. In that case, the measured amount of light does not change during the phase of totality. The light-curve is "flat" at the bottom of the minimum and the measured brightness indicates the intrinsic luminosity of the eclipsing star. Moreover, for a given orbit, the duration of the totality is proportional to the size of that star. This crucial information was not available for NN Ser . The brightness at minimum was simply too faint to allow any measurements of the system with available telescopes during this phase. For this reason, the properties of the eclipsing star could only be guessed. Reaching for the bottom The new VLT observations have overcome this. Thanks to the powerful combination of the 8.2-m ANTU telescope and the multi-mode FORS1 instrument, it was possible to measure the complete lightcurve of NN Ser , also during the darkest phase of the eclipse. This extreme observation demanded most careful preparation. Since there is very little light available, the longest possible integration time must be used in order to collect a sufficient number of photons and to achieve a reasonable photometric accuracy. However, the eclipse only lasts a few minutes and it would only be possible to exposure and read-out a few, normal exposures from the CCD camera, not enough to fully characterize the light curve at minimum. Reinhold Häfner decided to use another method. By having the telescope perform a controlled change of position on the sky ("drift") during the exposure, the light from NN Ser before, during and after the eclipse will not be registered on the same spot of the camera detector, but rather along a line. He carefully chose a direction in which this line would not cross those of other stars in the neighbourhood of NN Ser . This was ensured by rotating FORS1 to a predetermined position angle. The drift rate was fixed as one pixel (0.20 arcsec) per 3 seconds of time, a compromise between the necessary integration time and desired time resolution that would give the best chance to document the exact shape of the light-curve . In theory, this would then allow the measurement of the intensity along the recorded trail of NN Ser and hence its brightness at any given time during the eclipse. But how deep would the eclipse be? Would the resulting exposure on each pixel at minimum light be long enough to register a measurable signal? Seeing the light from the cool star! ESO PR Photo 30b/99 ESO PR Photo 30b/99 [Preview - JPEG: 400 x 464 pix - 156k] [Normal - JPEG: 800 x 927 pix - 584k] [High-Res - JPEG: 2292 x 2662 pix - 4.1M] ESO PR Photo 30c/99 ESO PR Photo 30c/99 [Preview - JPEG: 472 x 400 pix - 48k] [Normal - JPEG: 943 x 800 pix - 96k] Caption to ESO PR Photo 30b/99 : 18.5-min "drift" exposure with VLT ANTU and FORS1 of the sky field around the variable stellar system NN Ser (indicated with an arrow). The telescope moved 1 pixel (0.20 arcsec) every 3 seconds so that the images of the stars in the field are trailed from left to right. After some minutes, the very deep eclipse of NN Ser begins when the brightness drops dramatically during the first partial phase. The star is clearly visible at a constant level all through the total phase at minimum light. It then brightens during the second partial phase and is back to the former level after approximately 10.5 min. The FORS1 instrument was rotated by about 70° to ensure that the trail of NN Ser would not overlap those of the neighbouring stellar images during this special exposure. The field shown measures 2.7 x 2.7 armin 2 and may be compared with that shown in Photo 30a/99; it has the same orientation. Caption to ESO PR Photo 30c/99 : The light-curve of the variable stellar system NN Ser , as extracted from the drift exposure shown in Photo 30b/99 . The count rate is proportional to the brightness of the object; it is about 18,000 counts/pix outside the eclipse and decreases to about 70 counts during the total eclipse (since the full range of the eclipse is shown here, this low level is almost indistinguishable from 0 in this figure). Various properties of the two stars in the NN Ser system may be determined from the shape of the light-curve. The fact that the light-curve is "flat" at the bottom is a clear sign that the eclipse is total , i.e. the hot white dwarf star is completely hidden behind the cool red dwarf star. As ESO PR Photo 30b/99 shows, ANTU and FORS1 did manage this difficult observation! Aided by an excellent seeing of 0.5 arcsec, i.e. a good concentration of the light on each pixel, the recorded signal from NN Ser - although very faint - is well measurable at all times during the eclipse . In the mean, about 70 counts/pixel were registered at the minimum, down from about 18,000 outside the eclipse ( Photo 30c/99 ). The ratio is then about 250, corresponding to just over 6 magnitudes. The measured magnitude during eclipse is 23.0 in the V-band (green-yellow; wavelength 550 nm). Of even greater importance is the fact that the light-curve is found to be perfectly flat at the bottom, i.e. the eclipse is most certainly total . The white dwarf star is therefore being completely hidden as it moves behind the cooler and larger star, and we see only the latter during the eclipse. As explained above, this then allows to determine many of its properties. For instance, the fact that the light-curve has no obvious "soft shoulders" at the beginning and end of the total phase indicates that the white dwarf abruptly disappears from view. Thus the faint star cannot have a very extended atmosphere, otherwise the brightness change would have been more gradual. The total phase was found to last 7 m 37 s and each of the partial phases only 1 m 26 s. This shows that the orbit must be nearly perpendicular to the plane of the sky. This angle is referred to as the orbital inclination ; for NN Ser , it must be in the interval between 84° - 90°. A preliminary analysis indicates that the diameter of the cool star is between 200,000 and 245,000 km, i.e. about 1.5 times that of planet Jupiter. The white dwarf is even smaller; its diameter is between 25,000 and 31,000 km, or about twice the size of the Earth. The distance between the two stars is 660,000 km, or half the size of the Sun. Thus NN Ser is really a very small system - it would easily fit into our central star! The surface temperatures are widely different, about 55,000 and 2,800 degrees, respectively. By adding to this analysis earlier measurements of the orbital velocity of the white dwarf star, it is possible to estimate the mass of the cool star as between 0.10 and 0.14 solar masses. The white dwarf is significantly heavier, about 0.57 solar masses. Stellar objects with masses below approx. 0.08 solar mass are believed to be brown dwarfs , i.e. "still-born" stars in which nuclear fusion did not ignite. Since the mass of the cool star in NN Ser is near this limit, could it perhaps be such an object? A spectrum of the cool star ESO PR Photo 30d/99 ESO PR Photo 30d/99 [Preview - JPEG: 480 x 400 pix - 60k] [Normal - JPEG: 960 x 800 pix - 136k] Caption to ESO PR Photo 30d/99 : The spectrum of the cool dwarf star in the variable stellar system NN Ser . The 5 min exposure was obtained during the total phase of the eclipse, when the magnitude of the system was V = 23.0. Several TiO bands are clearly visible in this slightly smoothed tracing. A few deep and narrow "absorption" features are residuals from sky subtraction. The original resolution is 0.55 nm/pix. A spectral type of M6 or later is deduced for NN Ser . The spectrum of a more nearby (and hence much brighter) M6.5 dwarf star (temperature approx. 2600 degrees) is shown below for comparison. The VLT has already delivered the answer: it turns out to be no . The cool component of NN Ser may be a very small and faint object, but it is a real star that harbours nuclear processes in its interior. The temperature is on the high side for a brown dwarf, but the definite proof can only be obtained from the spectrum. ANTU and FORS1 were able to obtain a spectrum of NN Ser during the total eclipse, i.e. at a time when the visual magnitude was 23.0, cf. Photo 30d/99 . The exposure had to be limited to 5 min only, in order to ensure that there would be no contamination by extra light from the much brighter white dwarf companion star, as this is the case during the partial phases of the eclipse. Despite the difficult circumstances, it was possible to record a faint spectrum in the 600 - 900 nm (red - near-IR) wavelength interval. Although it is quite noisy, several molecular bands of TiO (titanium oxide) are well visible; VO (vanadium oxide) bands may also be present. They allow the classification of the spectrum as that of a very-late-type star, of spectral type M6 or later . This is in reasonable agreement with the mentioned temperature around 2800 degrees. In any case, this spectrum is quite unlike that of a brown dwarf, thus confirming that the cool companion star in NN Ser is a normal hydrogen-burning red dwarf star . NN Ser: a "missing link" in stellar theory The binary system NN Ser is now in an evolutionary stage that is referred to as the pre-cataclysmic phase. It will be followed by the cataclysmic phase , during which a gas stream will flow from the larger star to the smaller one. This phenomenon is characterized by frequent and abrupt increase in brightness. While many stars are known that are now in that unstable phase, only a few stars have ever been found to be in the preceding, transitory phase. Of these, NN Ser is the only one that has such a deep eclipse and for which it has now become possible to determine quite well the properties of the two components. NN Ser thus represents a most welcome example of a "missing link" in the theory of stellar evolution. It is therefore of great interest to perform further observations of such a rare object. They will include attempts to obtain more spectra to define the spectral type of the cool star very accurately. This will allow a critical check of current theories of atmospheres and evolutionary computations for the smallest and lightest stars. But for now, Reinhold Häfner looks forward to further nights at Paranal with the ESO astronomers there. "We worked together in a wonderful way during these demanding observations", he said, "and without their great support all of this would have been next to impossible!" Notes [1] These observations were carried out during "guaranteed observing time", allocated to the three German institutes that built the FORS instrument. More details about this instrument and related issues are available in ESO Press Release 14/98. [2] Astronomers designate variable stars according to the constellation in which they are seen in the sky and the order in which they are recognized as having variable brightness. For historical reasons, the first variable star in a given constellation (that is not already known by a greek letter, e.g. "Delta Cephei") is designated as "R" (e.g. "R Coronae Borealis"), the second as "S", etc. until "Z". Then follow "RR", "RS",..."RZ", "SS"..."SZ" until "ZZ" and only then from the beginning of the alphabet, "AA"..."AZ", "BA".. etc. until "QZ". How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http://www.eso.org../ ). ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

  15. SINFONI Opens with Upbeat Chords

    NASA Astrophysics Data System (ADS)

    2004-08-01

    First Observations with New VLT Instrument Hold Great Promise [1] Summary The European Southern Observatory, the Max-Planck-Institute for Extraterrestrial Physics (Garching, Germany) and the Nederlandse Onderzoekschool Voor Astronomie (Leiden, The Netherlands), and with them all European astronomers, are celebrating the successful accomplishment of "First Light" for the Adaptive Optics (AO) assisted SINFONI ("Spectrograph for INtegral Field Observation in the Near-Infrared") instrument, just installed on ESO's Very Large Telescope at the Paranal Observatory (Chile). This is the first facility of its type ever installed on an 8-m class telescope, now providing exceptional observing capabilities for the imaging and spectroscopic studies of very complex sky regions, e.g. stellar nurseries and black-hole environments, also in distant galaxies. Following smooth assembly at the 8.2-m VLT Yepun telescope of SINFONI's two parts, the Adaptive Optics Module that feeds the SPIFFI spectrograph, the "First Light" spectrum of a bright star was recorded with SINFONI in the early evening of July 9, 2004. The following thirteen nights served to evaluate the performance of the new instrument and to explore its capabilities by test observations on a selection of exciting astronomical targets. They included the Galactic Centre region, already imaged with the NACO AO-instrument on the same telescope. Unprecedented high-angular resolution spectra and images were obtained of stars in the immediate vicinity of the massive central black hole. During the night of July 15 - 16, SINFONI recorded a flare from this black hole in great detail. Other interesting objects observed during this period include galaxies with active nuclei (e.g., the Circinus Galaxy and NGC 7469), a merging galaxy system (NGC 6240) and a young starforming galaxy pair at redshift 2 (BX 404/405). These first results were greeted with enthusiasm by the team of astronomers and engineers [2] from the consortium of German and Dutch Institutes and ESO who have worked on the development of SINFONI for nearly 7 years. The work on SINFONI at Paranal included successful commissioning in June 2004 of the Adaptive Optics Module built by ESO, during which exceptional test images were obtained of the main-belt asteroid (22) Kalliope and its moon. Moreover, the ability was demonstrated to correct the atmospheric turbulence by means of even very faint "guide" objects (magnitude 17.5), crucial for the observation of astronomical objects in many parts of the sky. SPIFFI - SPectrometer for Infrared Faint Field Imaging - was developed at the Max Planck Institute for Extraterrestrische Physik (MPE) in Garching (Germany), in a collaboration with the Nederlandse Onderzoekschool Voor Astronomie (NOVA) in Leiden and the Netherlands Foundation for Research in Astronomy (ASTRON), and ESO. PR Photo 24a/04: SINFONI Adaptive Optics Module at VLT Yepun (June 2004) PR Photo 24b/04: SINFONI at VLT Yepun, now fully assembled (July 2004) PR Photo 24c/04: "First Light" image from the SINFONI Adaptive Optics Module PR Photo 24d/04: AO-corrected Image of a 17.5-magnitude Star PR Photo 24e/04: SINFONI undergoing Balancing and Flexure Tests at VLT Yepun PR Photo 24f/04: SINFONI "First Light" Spectrum of HD 130163 PR Photo 24g/04: Members of the SINFONI Adaptive Optics Module Commissioning Team PR Photo 24h/04: Members of the SPIFFI Commissioning Team PR Photo 24i/04: The Principle of Integral Field Spectroscopy (IFS) PR Photo 24j/04: The Orbital Motion of Linus around (22) Kalliope PR Photo 24k/04: SINFONI Observations of the Galactic Centre Region PR Photo 24l/04: SINFONI Observations of the Circinus Galaxy PR Photo 24m/04: SINFONI Observations of the AGN Galaxy NGC 7469 PR Photo 24n/04: SINFONI Observations of NGC 6240 PR Photo 24o/04: SINFONI Observations of the Young Starforming Galaxies BX 404/405 PR Video Clip 07/04: The Orbital Motion of Linus around (22) Kalliope SINFONI: A powerful and complex instrument ESO PR Photo 24a/04 ESO PR Photo 24a/04 The SINFONI Adaptive Optics Module Commissioning Setup [Preview - JPEG: 427 x 400 pix - 230k] [Normal - JPEG: 854 x 800 pix - 551k] ESO PR Photo 24b/04 ESO PR Photo 24b/04 SINFONI at the VLT Yepun Cassegrain Focus [Preview - JPEG: 414 x 400 pix - 222k] [Normal - JPEG: 827 x 800 pix - 574k] Captions: ESO PR Photo 24a/04 shows the SINFONI Adaptive Optics Module, installed at the 8.2-m VLT YEPUN telescope during the first tests in June 2004. At this time, SPIFFI was not yet installed. The blue ring is the Adaptive Optics Module. The yellow parts, with a weight of 800 kg, simulate SPIFFI. The IR Test Imager is located inside the yellow ring. On ESO PR Photo 24b/04, the Near-Infrared Spectrograph SPIFFI in its cryogenic aluminium cylinder has now been attached. A new and very powerful astronomical instrument, a world-leader in its field, has been installed on the Very Large Telescope at the Paranal Observatory (Chile), cf. PR Photos 24a-b/04. Known as SINFONI ("Spectrograph for INtegral Field Observation in the Near-Infrared"), it was mounted in two steps at the Cassegrain focus of the 8.2-m VLT YEPUN telescope. First Light of the completed instrument was achieved on July 9, 2004 and various test observations during the subsequent commissioning phase were carried out with great success. SINFONI has two parts, the Near Infrared Integral Field Spectrograph, also known as SPIFFI (SPectrometer for Infrared Faint Field Imaging), and the Adaptive Optics Module. SPIFFI was developed at the Max Planck Institute for Extraterrestrische Physik (MPE) (Garching, Germany), in a collaboration with the Nederlandse Onderzoekschool Voor Astronomie (NOVA) in Leiden, the Netherlands Foundation for Research in Astronomy (ASTRON) (The Netherlands), and the European Southern Observatory (ESO) (Garching, Germany). The Adaptive Optics (AO) Module was developed by ESO. Once fully commissioned, SINFONI will provide adaptive-optics assisted Integral Field Spectroscopy in the near-infrared 1.1 - 2.45 µm waveband. This advanced technique provides simultaneous spectra of numerous adjacent regions in a small sky field, e.g., of an interstellar nebula, the stars in a dense stellar cluster or a galaxy. Astronomers refer to these data as "3D-spectra" or "data cubes" (i.e., one spectrum for each small area in the two-dimensional sky field), cf. Appendix A. The SINFONI Adaptive Optics Module is based on a 60-element curvature system, similar to the Multi Application Curvature Adaptive Optics devices (MACAO), developed by the ESO Adaptive Optics Department and of which three have already been installed at the VLT (ESO PR 11/03); the last one in August 2004. Provided a sufficiently bright reference source ("guide star") is available within 60 arcsec of the observed field, the SINFONI AO module will ultimately offer diffraction-limited images (resolution 0.050 arcsec) at a wavelength of 2 µm. At the centre of the field, partial correction can be performed with guide stars as faint as magnitude 17.5. In about 6-months' time, it will benefit from a sodium Laser Guide Star, achieving a much better sky coverage than what is now possible. SPIFFI is a fully cryogenic near-infrared integral field spectrograph allowing observers to obtain simultaneously spectra of 2048 pixels within a 64 x 32 pixel field-of-view. In conjunction with the AO Module, it performs spectroscopy with slit-width sampling at the diffraction limit of an 8-m class telescope. For observations of very faint, extended celestial objects, the spatial resolution can be degraded so that both sensitivity and field-of-view are increased. SPIFFI works in the near-infrared wavelength range (1.1 - 2.45 µm) with a moderate spectral resolving power (R = 1500 to 4500). More information about the way SPIFFI functions will be found in Appendix A. "First Light with SINFONI's Adaptive Optics Module ESO PR Photo 24c/04 ESO PR Photo 24c/04 SINFONI AO "First Light" Image [Preview - JPEG: 400 x 482 pix - 106k] [Normal - JPEG: 800 x 963 pix - 256k] ESO PR Photo 24d/04 ESO PR Photo 24d/04 AO-corrected image of 17.5-magnitude Star [Preview - JPEG: 509 x 400 pix - 80k] [Normal - JPEG: 1018 x 800 pix - 182k] Captions: ESO PR Photo 24c/04 shows the "First Light" image obtained with the SINFONI AO Module and a high-angular-resolution near-infrared Test Camera during the night of May 31 - June 1, 2004. The magnitude of the observed star is 11 and the seeing conditions median. The diffraction limit at wavelength 2.2 µm of the 8.2-m telescope (FWHM 0.06 arcsec) was reached and is indicated by the bar. ESO PR Photo 24d/04: Image of a very faint guide star (visual magnitude 17.5), obtained with the SINFONI AO Module. To the right, the seeing-limited K-band image (FWHM 0.38 arcsec). To the left, the AO-corrected image (FWHM 0.145 arcsec). The ability to perform AO corrections on very faint guide objects is essential for SINFONI in order to observe very faint extragalactic objects. Because of the complexity of SINFONI, with its two modules, it was decided to perform the installation on the 8.2-m VLT Yepun telescope in two steps. The Adaptive Optics module was completely dismounted at ESO-Garching (Germany) and the corresponding 6 tons of equipment was air-freighted from Frankfurt to Santiago de Chile. The subsequent transport by road arrived at the Paranal Observatory on April 21, 2004. After 6 weeks of reintegration and testing in the Integration Hall, the AO Module was mounted on Yepun on May 30 - 31, together with a high-angular-resolution near-infrared Test Camera, cf. PR Photo 24a/04. Technical "First-Light" with this system was achieved around midnight on May 31st by observing a 11-magnitude star, cf. PR Photo 24c/04, reaching right away the theoretical diffraction limit of the 8.2-m telescope (0.06 arcsec) at this wavelength (2.2 µm). Following this early success, the ESO AO team continued the full on-sky tuning and testing of the AO Module until June 8, setting in particular a new world record by reaching a limiting guide-star magnitude of 17.5, two-and-a-half magnitudes (a factor of 10) fainter than ever achieved with any telescope! The ability to perform AO corrections on very faint guide objects is essential for SINFONI in order to observe very faint extragalactic objects. During this commissioning period, test observations were performed of the binary asteroid (22) Kalliope and its moon Linus. They were made by the ESO AO team and served to demonstrate the high performance of this ESO-built Adaptive Optics (AO) system at near-infrared wavelengths. More information about these observations, including a movie of the orbital motion of Linus is available in Appendix B. "First Light" with SINFONI ESO PR Photo 24e/04 ESO PR Photo 24e/04 SINFONI Undergoing Balancing and Flexure Tests at VLT Yepun [Preview - JPEG: 427 x 400 pix - 269k] [Normal - JPEG: 854 x 800 pix - 730k] ESO PR Photo 24f/04 ESO PR Photo 24f/04 SINFONI "First Light" Spectrum [Preview - JPEG: 427 x 400 pix - 94k] [Normal - JPEG: 854 x 800 pix - 222k] Captions: ESO PR Photo 24e/04 shows SINFONI attached to the Cassegrain focus of the 8.2-m VLT Yepun telescope during balancing and flexure tests. ESO PR Photo 24f/04: "First Light" "data cube" spectrum obtained with SINFONI on the bright star HD 130163 on July 9, 2004, as seen on the science data computer screen. This 7th-magnitude A0 V star was observed in the near-infrared H-band with a moderate seeing of 0.8 arcsec. The width of the slitlets in this image is 0.25 arcsec. The exposure time was 1 second. The fully integrated SPIFFI module was air-freighted from Frankfurt to Santiago de Chile and arrived at Paranal on June 5, 2004. The subsequent cool-down to -195 °C was done and an extensive test programme was carried through during the next two weeks. Meanwhile, the AO Module was removed from the telescope and the "wedding" with SPIFFI was celebrated on June 20 in the Paranal Integration Hall. All went well and the first AO-corrected test spectra were obtained immediately thereafter. The extensive tests of SINFONI continued at this site until July 7, 2004, when the instrument was declared fit for work at the telescope. The installation at the 8.2-m VLT Yepun telescope was then accomplished on July 8 - 9, cf. PR Photos 24b/04 and 24e/04. "First Light" was achieved in the early evening of July 9, 2004, only 30 min after the telescope enclosure was opened. At 19:30 local time, SINFONI recorded the first AO-corrected "data cube" with spectra of HD 130163, cf. PR Photo 24f/04. This 7th-magnitude star was observed in the near-infrared H-band with a moderate seeing of 0.8 arcsec. Test Observations with SINFONI ESO PR Photo 24k/04 ESO PR Photo 24k/04 SINFONI Observations of the Galactic Centre [Preview - JPEG: 427 x 400 pix - 213k] [Normal - JPEG: 854 x 800 pix - 511k] ESO PR Photo 24o/04 ESO PR Photo 24o/04 SINFONI Observations of the Distant Galaxy Pair BX 404/405 [Preview - JPEG: 481 x 400 pix - 86k] [Normal - JPEG: 962 x 800 pix - 251k] Captions: ESO PR Photo 24k/04: The coloured image (background) shows a three-band composite image (H, K, and L-bands) obtained with the AO imager NACO on the 8.2-m VLT Yepun telescope. On July 15, 2004, the new SINFONI instrument, mounted at the Cassegrain focus of the same telescope, observed the innermost region (the central 1 x 1 arcsec) of the Milky Way Galaxy in the combined H+K band (1.45 - 2.45 µm) during a total of 110 min "on-source". The insert (upper left) shows the immediate neighbourhood of the central black hole as seen with SINFONI. The position of the black hole is marked with a yellow circle. Later in the night (03:37 UT on July 16), a flare from the black hole ocurred (a zoom-in is shown in the insert at the lower left) and the first-ever infrared spectrum of this phenomenon was observed. It was also possible to register for the first time in great detail the near-infrared spectra of young massive stars orbiting the black hole; some of these are shown in the inserts at the upper right; stars are identified by their "S"-designations. The lower right inserts show the spectra of stars in "IRS 13 E", a very compact cluster of very young and massive stars, located about 3.5 arcsec to the south-west of the black hole. The wavefront reference ("guide") star employed for these AO observations is comparably faint (red magnitude approx. 15), and it is located about 20 arcsec away from the field centre. The seeing during these observations was about 0.6 arcsec. The width of the slitlets was 0.025 arcsec. See Appendix G for more detail. ESO PR Photo 24o/04 shows the distant galaxy pair BX 404/405, as recorded in the K-band (wavelength 2 µm, centered on the redshifted H-alpha line), without AO-correction because of the lack of a nearby, sufficiently bright "guide" star. The width of each slitlet was 0.25 arcsec and the seeing about 0.6 arcsec. The integration time on the galaxy was 2 hours "on-source". The image shown has been reconstructed by combining all of the spectral elements around the H-alpha spectral line. The spectrum of BX 405 (upper right) clearly reveals signs of a velocity shear while that of BX 404 does not. This may be a sign of rotation, a possible signature of a young disc in this galaxy. More information can be found in Appendix C. Until July 22, test observations on a number of celestial objects were performed in order to tune the instrument, to evaluate the performance and to demonstrate its astronomical capabilities. In particular, spectra were obtained of various highly interesting celestial objects and sky regions. Details about these observations (and some images obtained with the AO Module alone) are available in the Appendices to this Press Release: * a video of the motion of the moon Linus around the main-belt asteroid (22) Kalliope, providing the best view of this binary system obtained so far (Appendix B), * images and first-ever detailed spectra of many of the stars that move near the massive black hole at the Galactic Centre, with crucial information on the nature of the individual stars and their motions (Appendix C), * images and spectra of the heavily dust-obscured, active centre of the Circinus galaxy, one of the closest active galaxies, showing ordered rotation in this area and distinct broad and narrow components of the spectral line of Ca7+-ions (Appendix D), * images and spectra of the less obscured central area of NGC 7469, a more distant active galaxy, with spectral lines of molecular hydrogen and carbon monoxide showing a very different distribution of these species (Appendix E), * images and spectra of the Infrared Luminous Galaxy (ULIRG) NGC 6240, a typical galaxy merger, displaying important differences between the two nuclei (Appendix F), and * images and spectra of the young starforming galaxies BX 404/405, casting more light on the formation of disks in spiral galaxies (Appendix G) The SINFONI Teams ESO PR Photo 24g/04 ESO PR Photo 24g/04 Members of the SINFONI Adaptive Optics Commissioning Team [Preview - JPEG: 646 x 400 pix - 198k] [Normal - JPEG: 1291 x 800 pix - 618k] ESO PR Photo 24h/04 ESO PR Photo 24h/04 Members of the SPIFFI Commissioning Team [Preview - JPEG: 491 x 400 pix - 193k] [Normal - JPEG: 982 x 800 pix - 482k] Captions: ESO PR Photo 24g/04 Members of the SINFONI Adaptice Optics Commissioning Team in the VLT Control Room in the night between June 7 - 8, 2004. From left to right and top to bottom: Thomas Szeifert, Sebastien Tordo, Stefan Stroebele, Jerome Paufique, Chris Lidman, Robert Donaldson, Enrico Fedrigo, Markus Kissler Patig, Norbert Hubin, Henri Bonnet. ESO PR Photo 24h/04: Members of the SPIFFI Commissioning Team on August 17. From left to right, Roberto Abuter, Frank Eisenhauer, Andrea Gilbert and Matthew Horrobin. The first SINFONI results have been greeted with enthusiasm, in particular by the team of astronomers and engineers from the consortium of German and Dutch institutes and ESO who worked on the development of SINFONI for nearly 7 years. Some of the members of the Commissioning Teams are depicted in PR Photos 24g/04 and 24h/04; in addition to the SPIFFI team members present on the second photo, Walter Bornemann, Reinhard Genzel, Hans Gemperlein, Stefan Huber have also been working on the reintegration/commissioning in Paranal. Notes [1] This press release is issued in coordination between ESO, the Max-Planck-Institute for Extraterrestrial Physics (MPE) in Garching, Germany, and the Nederlandse Onderzoekschool Voor Astronomie in Leiden, The Netherlands. A German version is available at http://www.mpg.de/bilderBerichteDokumente/dokumentation/pressemitteilungen/2004/pressemitteilung20040824/index.html and a Dutch version at http://www.astronomy.nl/inhoud/pers/persberichten/30_08_04.html. [2] The SINFONI team consists of Roberto Abuter, Andrew Baker, Walter Bornemann, Ric Davies, Frank Eisenhauer (SPIFFI Principal Investigator), Hans Gemperlein, Reinhard Genzel (MPE Director), Andrea Gilbert, Armin Goldbrunner, Matthew Horrobin, Stefan Huber, Christof Iserlohe, Matthew Lehnert, Werner Lieb, Dieter Lutz, Nicole Nesvadba, Claudia Röhrle, Jürgen Schreiber, Linda Tacconi, Matthias Tecza, Niranjan Thatte, Harald Weisz (Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany), Anthony Brown, Paul van der Werf (NOVA, Leiden, The Netherlands), Eddy Elswijk, Johan Pragt, Jan Kragt, Gabby Kroes, Ton Schoenmaker, Rik ter Horst (ASTRON, Dwingeloo, The Netherlands), Henri Bonnet (SINFONI Project Manager), Roberto Castillo, Ralf Conzelmann, Romuald Damster, Bernard Delabre, Christophe Dupuy, Robert Donaldson, Christophe Dumas, Enrico Fedrigo, Gert Finger, Gordon Gillet, Norbert Hubin (Head of Adaptive Optics Dept.), Andreas Kaufer, Franz Koch, Johann Kolb, Andrea Modigliani, Guy Monnet (Head of Telescope Systems Division), Chris Lidman, Jochen Liske, Jean Louis Lizon, Markus Kissler-Patig (SINFONI Instrument Scientist), Jerome Paufique, Juha Reunanen, Silvio Rossi, Riccardo Schmutzer, Armin Silber, Stefan Ströbele (SINFONI System Engineer), Thomas Szeifert, Sebastien Tordo, Leander Mehrgan, Joerg Stegmeier, Reinhold Dorn (European Southern Observatory). Contacts Frank Eisenhauer Max-Planck-Institut für Extraterrestrische Physik (MPE) Garching, Germany Phone: +49-89-30000-3563 Email: eisenhau@mpe.mpg.de Paul van der Werf Leiden Observatory Leiden, The Netherlands Phone: +31-71-5275883 Email: pvdwerf@strw.leidenuniv.nl Henri Bonnet European Southern Observatory (ESO) Email: hbonnet@eso.org Reinhard Genzel Max-Planck-Institut für Extraterrestrische Physik (MPE) Garching, Germany Phone: +49-89-30000-3280 Email: Norbert Hubin European Southern Observatory (ESO) Email: nhubin@eso.org Appendix A: Integral Field Spectroscopy as a Powerful Discovery Tool ESO PR Photo 24i/04 ESO PR Photo 24i/04 How Integral Field Spectroscopy Works [Preview - JPEG: 400 x 425 pix - 127k] [Normal - JPEG: 800 x 850 pix - 366k] Caption: ESO PR Photo 24i/04 shows the principle of Integrated Field Spectroscopy (IFS). The detailed explanation is found in the text. How does SINFONI work? What is Integral Field Spectroscopy (IFS)? The idea of IFS is to obtain a spectrum of each defined spatial element ("spaxel") in the field-of-view. Several techniques to do this are available - in SINFONI, the slicer principle is applied. This involves (PR Photo 24i/04) that * the two-dimensional field-of-view is cut into slices, the so-called slitlets (short slits in contrast to normal long-slit spectroscopy), * the slitlets are then arranged next to each other to form a pseudo-long-slit, * a grating is used to disperse the light, and * the photons are detected with a Near-InfraRed detector. Following data reduction, the set of generated spectra can be re-arranged in the computer to form a 3-dimensional "data cube" of two spatial, and one wavelength dimension. Thus the term "3D-Spectroscopy" is sometimes used for IFS. Appendix B: Linus' orbital motion around Kalliope ESO PR Photo 24j/04 ESO PR Photo 24j/04 Asteroid Kalliope and its Moon Linus [Preview - JPEG: 400 x 427 pix - 50k] [Normal - JPEG: 800 x 854 pix - 136k] ESO PR Video 07/04 ESO PR Video 07/04 The Motion of Linus around Kalliope [MPG: 800 x 800 pix - 128k] [AVI : 800 x 800 pix - 176k] [Animated GIF : 800 x 800 pix - 592k] Caption: ESO PR Photo 24j/04 and Video Clip 07/04 show the best-ever images of the moon Linus orbiting Asteroid (22) Kalliope. It was obtained with the SINFONI Adaptive Optics Module and a high-angular-resolution near-infrared Test Camera during commissioning in June 2004. At minimum separation, the satellite approaches Kalliope to 0.33 arcsec, i.e. the angle under which a 1 Euro coin is seen at a distance of 15 kilometers. At maximum separation, the angular distance is nearly twice as large. For clarity, the brightness of the asteroid has been artificially decreased by a factor of 15, to the level of the moon. This image processing technique also permits to perceive the variation of the asteroid's shape as Kalliope spins around its own axis with a period of 4.15 hours. The asteroid, with an angular diameter of 0.11 arcsec, is barely resolved in these VLT images (resolution 0.06 arcsec at wavelength 2.2 µm). The satellite measures about 50 km acroos and orbits Kalliope at a distance of about 1000 kilometers. ESO Video Clip 07/04 shows the 3.6-day orbital motion of the satellite (moon) Linus around the main-belt asteroid (22) Kalliope. Kalliope orbits the Sun between Mars and Jupiter; it measures about 180 km across and the diameter of its moon is 50 km. This system was observed with the SINFONI AO Module for short periods over four consecutive nights. Linus moves around Kalliope in a circular orbit, at a distance of 1000 km and with a direction of motion similar to the rotation of Kalliope (prograde rotation); the orbital plane of the moon was seen under a 60°-angle with respect to the line-of-sight. The unobserved parts of this orbit are indicated by a dotted line. A hypothetical observer on the surface of Kalliope would live in a strange world: the days would be 14 hours long, and the sky would be filled by a moon five times bigger than our own! The brightness changes of the Linus images is due to variations in the sky conditions at the time of the observations. Rapid changes in the atmosphere result in variations in the sharpness of the corrected images. During the first two nights, seeing conditions were very good, but less so during the last two nights; this can be seen as a slight loss of sharpness of the corresponding satellite images. The discovery of this asteroid satellite, named Linus after the son of Kalliope, the Greek muse of heroic poetry, was first reported in September 2001 by a group of astronomers using the Canadian-France-Hawaii telescope on Mauna Kea (Hawaii, USA). Although previously believed to consist of metal-rich material, the discovery of Linus allowed the scientists to determine the mean density of Kalliope as ~ 2 g/cm3, a rather low value and not consistent with a metal-rich object. Kalliope is now believed to be a "rubble-pile" stony asteroid. Its porous interior is due to a catastrophic collision with another, smaller asteroid early in its history and which also gave birth to Linus. Other references related to Kalliope can be found in the International Astronomical Union Circular (IAUC) 7703 (2001) and a research article "A low density M-type asteroid in the main-belt" by Margot and Brown (Science 300, 193, 2003). Appendix C: Stars at the Galactic Centre and a Flare from the Black Hole ESO PR Photo 24k/04 ESO PR Photo 24k/04 SINFONI Observations of the Galactic Centre [Preview - JPEG: 427 x 400 pix - 213k] [Normal - JPEG: 854 x 800 pix - 511k] Caption: ESO PR Photo 24k/04: The coloured image (background) shows a three-band composite image (H, K, and L-bands) obtained with the AO imager NACO on the 8.2-m VLT Yepun telescope. On July 15, 2004, the new SINFONI instrument, mounted at the Cassegrain focus of the same telescope, observed the innermost region (the central 1 x 1 arcsec) of the Milky Way Galaxy in the combined H+K band (1.45 - 2.45 µm) during a total of 110 min "on-source". The insert (upper left) shows the immediate neighbourhood of the central black hole as seen with SINFONI. The position of the black hole is marked with a yellow circle. Later in the night (03:37 UT on July 16), a flare from the black hole ocurred (a zoom-in is shown in the insert at the lower left) and the first-ever infrared spectrum of this phenomenon was observed. It was also possible to register for the first time in great detail the near-infrared spectra of young massive stars orbiting the black hole; some of these are shown in the inserts at the upper right; stars are identified by their "S"-designations. The lower right inserts show the spectra of stars in "IRS 13 E", a very compact cluster of very young and massive stars, located about 3.5 arcsec to the south-west of the black hole. The wavefront reference ("guide") star employed for these AO observations is comparably faint (red magnitude approx. 15), and it is located about 20 arcsec away from the field centre. The seeing during these observations was about 0.6 arcsec. The width of the slitlets was 0.025 arcsec. The Milky Way Centre is a unique laboratory for studying physical processes that are thought to be common in galactic nuclei. The Galactic Centre is not only the best studied case of a supermassive black hole, but the region also hosts the largest population of high-mass stars in the Galaxy. Diffraction-limited near-IR integral field spectroscopy offers a unique opportunity for exploring in detail the physical phenomena responsible for the active phases of this supermassive black hole, and for studying the dynamics and evolution of the star cluster in its immediate vicinity. Earlier observations with the VLT have been described in ESO PR 17/02 and ESO PR 26/03. With the new SINFONI observations, some of which are displayed in PR Photo 24k/04, it was possible to obtain for the first time very detailed near-infrared spectra of several young and massive stars orbiting the black hole at the centre of our galaxy. The presence of spectral signatures from ionised hydrogen (the Bracket-gamma line) and Helium clearly classify these stars as young, massive early-type stars. They are comparatively short-lived, and the large fraction of such stars in the immediate vicinity of a supermassive black hole is a mystery. The first SINFONI observations of the stellar populations in the innermost Galactic Centre region will now help to explain the origin and formation process of those stars. Moreover, the observed spectral features allow measuring their motions along the line-of-sight (the "radial velocities"). Combining them with the motions in the sky (the "proper motions") obtained from previous observations with the NACO instrument (ESO PR 17/02), it is now possible to determine all orbital parameters for the "S"-stars. This in turn makes it possible to measure directly the mass and the distance of the supermassive black hole at the centre of our galaxy. But not only this! Even more exciting, it became possible to register for the first time the infrared spectrum of a flare from the Galactic Centre black hole (cf. ESO PR 26/03). From the earlier imaging observations, it is known that such outbursts occur approximately once every 4 hours, giving us a uniquely detailed glimpse of a black hole feeding on left-over gas in its close surroundings. It is only the innovative technique of SINFONI - providing spectra for every pixel in a diffraction-limited image - that made it possible to capture the infrared spectrum of such a flare. Such spectra from SINFONI will soon allow to understand better the physics and mechanisms involved in the flare emission. Appendix D: The Active Circinus Galaxy ESO PR Photo 24l/04 ESO PR Photo 24l/04 SINFONI Observations of the Circinus Galaxy [Preview - JPEG: 824 x 400 pix - 324k] [Normal - JPEG: 412 x 800 pix - 131k] Caption: ESO PR Photo 24l/04: The Circinus galaxy - one of the nearest galaxies with an active centre (AGN) - was observed in the K-band (wavelength 2 µm) using the nucleus to guide the SINFONI AO Module. The seeing was 0.5 arcsec and the width of each slitlet 0.025 arcsec; the total integration time on the galaxy was 40 min. At the top is a K-band image of the central arcsec of the galaxy (left insert) and a K-band spectrum of the nucleus (right). In the lower half are images (left) in the light of ionised hydrogen (the Brackett-gamma line) and molecular hydrogen lines (H2), together with their combined rotation curve (middle), as well as images of the broad and narrow components of the high excitation [Ca VIII] spectral line (right). The false-colours in the images represent regions of different surface brightness. At a distance of about 13 million light-years, the Circinus galaxy is one of the nearest galaxies with a very active black hole at the centre. It is seen behind a highly obscured sky field, only 3° from the Milky Way main plane in the southern constellation of this name ("The Pair of Compasses"). Using the nucleus of this galaxy to guide the AO Module, SINFONI was able to zoom in on the central arcsec region - only 60 light-years across - and to map the immediate environment of the black hole at the centre, cf. PR Photo 24l/04. The K-band (wavelength 2 µm) image (insert at the upper left) displays a very compact structure; the emission recorded at this wavelength comes from hot dust heated by radiation from the accretion disc around the black hole. However, as may be seen in the two inserts below, both the emission from ionized hydrogen (the Brackett-gamma line) and molecular hydrogen (H2) are more extended, up to about 30 light-years. As these spectral lines (cf. the spectral tracing at the upper right) are quite narrow and show ordered rotation up to ±40km/s, it is likely that they arise from star formation in a disk around the central black hole. A surprise from the SINFONI observations is that the spectral line of Ca7+-ions (seven times ionised Calcium atoms, or [Ca VIII], which are produced by the ionizing effect of very energetic ultraviolet radiation) in this area appears to have distinct broad and narrow components (images at the lower right). The broad component is centred on the region around the black hole, and probably arises in the so-called "Broad-Line Region". The narrow component is displaced to the north-west and most likely indicates a region where there is a direct line-of-sight from the black hole to some gas clouds. Appendix E: The Active Nucleus in NGC 7469 ESO PR Photo 24m/04 ESO PR Photo 24m/04 SINFONI Observations of NGC 7469 [Preview - JPEG: 470 x 400 pix - 116k] [Normal - JPEG: 939 x 800 pix - 324k] Caption: ESO PR Photo 24m/04: NGC 7469 was observed in K band (wavelength 2 µm) using the nucleus to guide the adaptive optics. The width of each slitlet was 0.025 arcsec and the seeing was 1.1 arcsec. The total integration time on the galaxy was 70 min "on-source". To the upper left is a K-band image (2 µm) of the central arcsec of the NGC7469 and to the upper right, the spectrum of the nucleus. To the lower left is an image of the molecular hydrogen line, together with its rotation curve. There is an image in the light of ionized hydrogen (Bracket-gamma line) at the lower middle and an image of the CO 2-0 absorption bandhead which traces young stars (lower right). The galaxy NGC 7469 (seen north of the celestial equator in the constellation Pegasus) also hosts an active galactic nucleus, but contrary to the Circinus galaxy, it is relatively unobscured. Since NGC 7469 is at a much larger distance, about 225 million light-years, the 0.15 arcsec resolution achieved by SINFONI here corresponds to about 165 light-years. The K-band image (PR Photo 24m/04) shows the bright, compact nucleus of this galaxy, and the spectrum displays very broad lines of ionized hydrogen (the Brackett-gamma line) and helium. This emission arises in the "Broad-Line" region which is still unresolved, as shown by the Brackett-gamma image. On the other hand, the molecular hydrogen extends up to 650 light-years from the centre and shows an ordered rotation. In contrast, the image obtained in the light of CO-molecules - which directly traces late-type stars typical for starbursts - appears very compact. These results confirm those obtained by means of earlier AO observations, but with the new SINFONI data corresponding to various spectral lines, the detailed, two-dimensional structure and motions close to the central black hole are now clearly revealed for the first time. Appendix F: The Galaxy Merger NGC 6240 ESO PR Photo 24n/04 ESO PR Photo 24n/04 SINFONI Observations of NGC 6240 [Preview - JPEG: 506 x 400 pix - 96k] [Normal - JPEG: 1011 x 800 pix - 277k] Caption: ESO PR Photo 24n/04: The galaxy merger system NGC 6240 was observed with SINFONI in the K-band (wavelength 2 µm). This object has two nuclei; the image of the southern one is also shown enlarged, together with the corresponding spectrum. The width of each slitlet was 0.025 arcsec and the seeing was 0.8 arcsec. The total integration time on the galaxy was 80 min. The false-colours in the images represent regions of different surface brightness. The infrared-luminous galaxy NGC 6240 in the constellation Ophiuchus (The Serpent-holder) is in many ways the prototype of a gas-rich, infrared-(ultra-)luminous galaxy merger. This system has two rapidly rotating, massive bulges/nuclei at a projected angular separation of 1.6 arcsec. Each of them contains a powerful starburst region and a luminous, highly obscured, X-ray-emitting supermassive black hole. As such, NGC 6240 is probably a nearby example of dust and gas-rich galaxy merger systems seen at larger distances. NGC6240 is also the most luminous, nearby source of molecular hydrogen emission. It was observed in the K-band (wavelength 2 µm), using a faint star at a distance of about 35 arcsec as the AO "guide" star. The starburst activity is traced by the ionized gas and occurs mostly at the two nuclei in regions measuring around 650 light-years across. The distribution of the molecular gas is very different. It follows a complex spatial and dynamical pattern with several extended streamers. The high-resolution SINFONI data now makes it possible - for the first time - to investigate the distribution and motion of the molecular gas, as well as the stellar population in this galaxy with a "resolution" of about 80 light-years. Appendix G: Motions in the Young Star-Forming Galaxies BX 404/405 ESO PR Photo 24o/04 ESO PR Photo 24o/04 SINFONI Observations of the Distant Galaxy Pair BX 404/405 [Preview - JPEG: 481 x 400 pix - 86k] [Normal - JPEG: 962 x 800 pix - 251k] Caption: ESO PR Photo 24o/04 shows the distant galaxy pair BX 404/405, as recorded in the K-band (wavelength 2 µm, centered on the redshifted H-alpha line), without AO-correction because of the lack of a nearby, sufficiently bright "guide" star. The width of each slitlet was 0.25 arcsec and the seeing about 0.6 arcsec. The integration time on the galaxy was 2 hours "on-source". The image shown has been reconstructed by combining all of the spectral elements around the H-alpha spectral line. The spectrum of BX 405 (upper right) clearly reveals signs of a velocity shear while that of BX 404 does not. This may be a sign of rotation, a possible signature of a young disc in this galaxy. How and when did the discs in spiral galaxies like the Milky Way form? This is one of the longest-standing puzzles in modern cosmology. Two general models presently describe how disk galaxies may form. One is based on a scenario in which there is a gentle collapse of gas clouds that collide and lose momentum. They sink towards a "centre", thereby producing a disc of gas in which stars are formed. The other implies that galaxies grow through repeated mergers of smaller gas-rich galaxies. Together they first produce a spherical mass distribution at the centre and any remaining gas then settles into a disk. Recent studies of stars in the Milky Way system and nearby spiral galaxies suggest that the discs now present in these systems formed about 10,000 million years ago. This corresponds to the epoch when we observe galaxies at redshifts of about 1.5 - 2.5. Interestingly, studies of galaxies at these distances seem consistent with current ideas about when disks may have formed, and there is some evidence that most of the mass in the galaxies was also assembled at that time. In any case, the most direct way to verify such a connection is to observe galaxies at redshifts 1.5-2.5, in order to elucidate whether their observed properties are consistent with velocity patterns of rotating disks of gas and stars. This would be visible as a "velocity shear", i.e., a significant difference in velocity of neigbouring regions. In addition, such observations may provide a good test of the above mentioned hypotheses for how discs may have formed. Various groups of astrophysicists in the US and Europe have developed observational selection criteria which may be used to identify galaxies with properties similar to those expected for young disc galaxies. Observations with SINFONI was made of one of these objects, the galaxy pair BX 404/405 discovered by a group of astronomers at Caltech (USA). For BX 405, clear signs were found of a "velocity shear" like that expected for rotation of a forming disk, but the other object does not show this. It may thus be that the properties of star-forming galaxies at this epoch are quite complex and that only some of them have young disks.