Science.gov

Sample records for jararaca serpentes viperidae

  1. A nesting of vipers: Phylogeny and historical biogeography of the Viperidae (Squamata: Serpentes).

    PubMed

    Wüster, Wolfgang; Peppin, Lindsay; Pook, Catharine E; Walker, Daniel E

    2008-11-01

    Despite their medical interest, the phylogeny of the snake family Viperidae remains inadequately understood. Previous studies have generally focused either on the pitvipers (Crotalinae) or on the Old World vipers (Viperinae), but there has been no comprehensive molecular study of the Viperidae as a whole, leaving the affinities of key taxa unresolved. Here, we infer the phylogenetic relationships among the extant genera of the Viperidae from the sequences of four mitochondrial genes (cytochrome b, NADH subunit 4, 16S and 12S rRNA). The results confirm Azemiops as the sister group of the Crotalinae, whereas Causus is nested within the Viperinae, and thus not a basal viperid or viperine. Relationships among the major clades of Viperinae remain poorly resolved despite increased sequence information compared to previous studies. Bayesian molecular dating in conjunction with dispersal-vicariance analysis suggests an early Tertiary origin in Asia for the crown group Viperidae, and rejects suggestions of a relatively recent, early to mid-Tertiary origin of the Caenophidia. PMID:18804544

  2. 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

  3. 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

  4. Prospection, structural analysis and phylogenetic relationships of endogenous gamma-phospholipase A(2) inhibitors in Brazilian Bothrops snakes (Viperidae, Crotalinae).

    PubMed

    Estevão-Costa, Maria Inácia; Rocha, Bruno Coelho; de Alvarenga Mudado, Maurício; Redondo, Rodrigo; Franco, Glória Regina; Fortes-Dias, Consuelo Latorre

    2008-07-01

    During the last 20 years, there have been an increasing number of reports on endogenous phospholipase A(2) inhibitors (PLIs) in the sera of snakes. These studies have demonstrated the existence of three different structural classes of PLIs (alpha, beta and gamma). The gamma class members are potent inhibitors of phospholipases A(2) (PLA(2)) from the venom of Viperidae snakes. These enzymes, together with the mammalian pro-inflammatory PLA(2), belong to the IIA class of the PLA(2)-superfamily. Although coming from distinct sources, these phospholipases A(2) share main structural features. For this reason, gammaPLIs have been considered as potential models for the development of selective inhibitors of pro-inflammatory PLA(2) in humans. In spite of the rich diversity of the ophidian fauna in Brazil, only two gammaPLI representatives, from Crotalus durissus terrificus and Lachesis muta, have been described in Brazilian snakes so far. Here we investigated the presence of transcripts of novel gammaPLIs in six Bothrops species (Viperidae, Crotalinae) commonly found in our country: Bothrops alternatus, Bothrops erythromelas, Bothrops jararaca, Bothrops jararacussu, Bothrops moojeni and Bothrops neuwiedi. gammaPLI transcripts were present in every species analysed. The deduced mature proteins possessed 181 amino acid residues following a 19-residue signal peptide, similar to the gammaPLIs from C. d. terrificus taken as our model, with the exception of the deduced proteins from B. erythromelas and B. neuwiedi snakes. In these particular cases, an insertion of 4-amino acid residues was consistently present. A Bayesian tree was obtained for the Brazilian Bothrops gammaPLIs, showing four clusters: (1) L. muta and B. jararacussu, (2) B. alternatus, (3) B. erythromelas and B. neuwiedi, (4) B. jararaca and B. moojeni. Detailed structural analysis and further comparisons of these novel Bothrops inhibitors with gammaPLIs from New and Old World snakes are provided. PMID:18620721

  5. Inhibition of hemorrhagic and edematogenic activities of snake venoms by a broad-spectrum protease inhibitor, murinoglobulin; the effect on venoms from five different genera in Viperidae family.

    PubMed

    Ribeiro Filho, Wilker; Sugiki, Masahiko; Yoshida, Etsuo; Maruyama, Masugi

    2003-08-01

    In order to obtain basic data on the effect of broad-spectrum protease inhibitor against local symptoms of Viperidae snake envenomation, inhibitory capacity of rat murinoglobulin on local hemorrhagic and edematogenic activities of venoms from Crotalus atrox, Bothrops jararaca, Lachesis muta muta, Trimeresurus flavoviridis and Echis carinatus sochureki were examined. Murinoglobulin, pre-incubated with the crude venoms at 37 degrees C for 15 min, inhibited hemorrhagic activity of all five venoms to various extents. The activity of C. atrox was almost completely inhibited at the murinoglobulin/venom ratio (w/w) of 20. The activity of B. jararaca, Lachesis muta muta and T. flavoviridis venoms was considerably inhibited at the ratio of 20 (77.2, 80.0 and 86.2% inhibition, respectively), however some of the activity still remained even at the ratio of 40 (84.2, 79.8 and 86.2% inhibition, respectively). Among the five venoms, E. c. sochureki venom is quite resistant to murinoglobulin treatment and statistically significant inhibition was only found at the ratio of 40 (64.1% inhibition). Fibrinolytic and gelatinase activities were more susceptible to murinoglobulin inhibition. The treatment at the ratios of 10 and 20 almost completely inhibited respectively the fibrinolytic and the gelatinase activities of all the venoms. Murinoglobulin treatment also significantly inhibited the edematogenic activity of L. muta muta, T. flavoviridis and Echis carinatus sochureki. The treatment of murinoglobulin at the ratio of 40 considerably suppressed the swelling up to 60 min after subcutaneous injection of L. muta muta and E. c. sochureki venoms, and up to 30 min after T. flavoviridis venom injection. Murinoglobulin is a potent inhibitor against local effects of multiple snake venoms in Viperidae family. PMID:12906888

  6. [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

  7. 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

  8. Historical biogeography of the Western Rattlesnake (Serpentes: viperidae: Crotalus viridis), inferred from mitochondrial DNA sequence information.

    PubMed

    Pook, C E; Wüster, W; Thorpe, R S

    2000-05-01

    We infer the phylogeography of the Western Rattlesnake (Crotalus viridis) using phylogenetic analysis of mitochondrial DNA sequences from 1345 bp of the genes for cytochrome b and NADH dehydrogenase subunit 4. Two main clades are revealed: one includes populations from east and south of the Rocky Mountains (conventionally referred to as Crotalus viridis viridis and C. v. nuntius), and the other consists of populations west of the Rocky Mountains. Within the western clade, a population from southern Arizona (C. v. cerberus) represents the sister taxon to the remaining western populations. The conventional subspecies recognized in this species do not fully correspond to the phylogenetic pattern, and a review of the systematic status of several populations is needed. Our data allow the inferences that small body size evolved twice and that the ability of one population (C. v. concolor) to secrete highly lethal toxins related to Mojave toxin arose within the complex. Our phylogeny should represent the basis for further studies on the causes of geographical variation in this complex. PMID:10837156

  9. 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

  10. [Biological and immunological characteristics of the poison of Bothrops cotiara (Serpentes: Viperidae)].

    PubMed

    de Roodt, Adolfo Rafael; Estévez, Judith; Dolab, Jorge Adrián; Manzanelli, Marcelo Víctor; Piñeiro, Nicolás; Paniagua, Jorge Francisco; Vogt, Alejandro Urs

    2006-09-01

    Bothrops cotiara is a venomous snake sporadically found in the province of Misiones in Argentina, South of Brazil and Paraguay. Data on the clinics of the envenomation produced by its bite and on its venom are scarce. There is no information on the neutralizing capacity of the antivenoms available. In this study, the lethal potency, hemorrhagic, necrotizing, coagulant and thrombin-like, defibrinogenating, indirect hemolytic and fibrinolytic activities of the venom of B. cotiara specimens from the province of Misiones were determined. The toxic activities were within the range of those described for the other Bothrops species from Argentina, and the electrophoretic and chromatographic studies showed similarities with those described for the other bothropic venoms. The immunochemical reactivity of six South American anti Viper antivenoms (ELISA) have a strong reactivity with all the antivenoms studied. The neutralizing capacity of three of these therapeutic antivenoms against the lethal potency and hemorrhagic, necrotizing, coagulant, thrombin-like and hemolytic activities showed a very close neutralizing capacity. Our data strongly suggest that the antivenoms for therapeutic use available in this area of South America are useful to neutralize the toxic and enzymatic activities of the venom of this uncommon specie of Bothrops. PMID:18491630

  11. 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

  12. 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

  13. [Toxicity and neutralization of venoms from Peruvian snakes of the genera Bothrops and Lachesis (Serpentes: Viperidae)].

    PubMed

    Incio Ruiz, R; Incio Ruiz, L; Martínez-Vargas, A Z; Salas Arruz, M; Gutiérrez, J M

    1993-12-01

    The lethal potencies (Median Lethal Dose) of the venoms of Peruvian snakes (Bothrops atrox, Bothrops barnetti, Bothrops pictus and Lachesis muta muta) were determined in mice by using intravenous and intraperitoneal routes of injection. In addition, the neutralizing ability of three antivenoms (bothropic polyvalent, bothropic bivalent and lachetic) was studied by preincubation-type experiments. B. pictus venom had the highest lethality by the intraperitoneal route whereas B. atrox venom had the highest lethality when tested by the intravenous route. The three antivenoms were effective in neutralizing lethality of the homologous venoms. Bivalent antivenom was more effective than polyvalent antivenom in the neutralization of B. pictus venom. On the basis of these findings, the use of bivalent bothropic antivenom is recommended in the Pacific coastal regions of Perú, whereas polyvalent bothropic antivenom is recommended in the oriental jungle regions of the country. PMID:7701074

  14. 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

  15. Hypericum brasiliense plant extract neutralizes some biological effects of Bothrops jararaca snake venom

    PubMed Central

    Assafim, Mariane; de Coriolano, Eduardo Coriolano; Benedito, Sérgio Eufrázio; Fernandes, Caio Pinho; Lobo, Jonathas Felipe Revoredo; Sanchez, Eladio Florez; Rocha, Leandro Machado; Fuly, André Lopes

    2011-01-01

    Alternative treatments for snake bite are currently being extensively studied, and plant metabolites are considered good candidates for such purpose. Here, the ability of a crude ethanolic extract of Hypericum brasiliense plant in neutralizing Bothrops jararaca snake venom was investigated by in vitro (coagulation, hemolysis or proteolysis) and in vivo (hemorrhage, lethality and edema) biological assays. We describe for the first time the ability of H. brasiliense extracts to inhibit some pharmacological effects of a Brazilian snake venom. Inhibitory assays were performed by incubating B. jararaca venom with H. brasiliense extracts for 30min at room temperature before the assays were performed. The results showed that H. brasiliense extracts impaired lethality, edema, hemorrhage, hemolysis, proteolysis as well as fibrinogen or plasma clotting induced by B. jararaca venom. This indicates that H. brasiliense extracts can provide promising agents to treat B. jararaca envenomation. PMID:21654896

  16. A Double Take at 'Serpent' Drift

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit took this microscopic imager picture of the drift dubbed 'Serpent' on Spirit's 73rd martian day on Mars after successfully digging into the side of the drift. The image is the first-ever microscopic look inside a drift. It captures only the scuffed interior of the Serpent drift and is dominated by larger pea-shaped particles. These grains are not natural to the inside of the drift, but are crust particles that have tumbled into the scuffed area as a result of the digging. These grains lost their dust cover in the process of falling into the scuff, giving scientists clues about the strength -- or lack of strength -- of the bond between the dust and sand particles.

    Most interesting to scientists are the fine grains making up the interior of Serpent drift. The grains of sand found within drifts or dunes on Earth are usually about 200 micrometers (.008 inches) in diameter -- much like sand on a beach. On Earth, dunes are formed when sand particles of this size are bounced across a surface by wind and collect together as drifts. Smaller particles, like the ones making up Serpent drift, would not necessarily collect into a dune on Earth, but would more likely be distributed across the surface like dust. The fine grains making up the interior of Serpent drift are no larger than 50 or 60 micrometers (.002 inches) and can be compared to silt on Earth.

    How did this very fine material manage to accumulate into a drift? Earth-based tests that simulate the wind speed and atmospheric density of Mars have found it difficult to reproduce dunes with grain particles as small as those found in the Serpent drift. However, Earth-based tests cannot duplicate the gravity of Mars, which is one-third that of the gravity on Earth. This environmental factor is a likely contributor to the diminutive material making up Serpent drift.

  17. A Double Take at 'Serpent' Drift

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit took this microscopic imager picture of the drift dubbed 'Serpent' on Spirit's 73rd martian day on Mars after successfully digging into the side of the drift. The image, which has a black box at the top caused by missing data, captures a transition part of the drift where lighter, undisturbed material meets disturbed, darker material. The microscopic view of the undisturbed material reveals sphere-like grains with diameters between one and two millimeters (.04 and .08 inches), which are similar to the grains Spirit observed in other drift areas near Spirit's landing site, Gusev Crater. These larger grains form a single layer or crust on the surface of the drift and are covered in a fine layer of martian dust.

    Most interesting to scientists are the fine grains making up the interior of Serpent drift. The grains of sand found within drifts or dunes on Earth are usually about 200 micrometers (.008 inches) in diameter--much like sand on a beach. On Earth, dunes are formed when sand particles of this size are bounced across a surface by wind and collect together as drifts. Smaller particles, like the ones making up Serpent drift, would not necessarily collect into a dune on Earth, but would more likely be distributed across the surface like dust. The fine grains making up the interior of Serpent drift are no larger than 50 or 60 micrometers (.002 inches) and can be compared to silt on Earth.

    How did this very fine material managed to accumulate into a drift? Earth-based tests that simulate the wind speed and atmospheric density of Mars have found it difficult to reproduce dunes with grain particles as small as those found in the Serpent drift. However, Earth-based tests cannot duplicate the gravity of Mars, which is one-third that of the gravity on Earth. This environmental factor is a likely contributor to the diminutive material making up Serpent drift.

  18. 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

  19. 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

  20. When continents collide: phylogeny, historical biogeography and systematics of the medically important viper genus Echis (Squamata: Serpentes: Viperidae).

    PubMed

    Pook, Catharine E; Joger, Ulrich; Stümpel, Nikolaus; Wüster, Wolfgang

    2009-12-01

    We analyze the phylogeny of the medically important and taxonomically unresolved viper genus Echis using four mitochondrial gene fragments. The results show that the populations of the genus fall into four main clades: the Echis carinatus, E. coloratus, E. ocellatus and E. pyramidum groups. The E. pyramidum and E. coloratus groups are sister taxa but the interrelationships of this clade and the E. ocellatus and E. carinatus groups are unresolved. The initial divergence of the genus appears to coincide with the collision between Afro-Arabia and Eurasia, and that between the E. coloratus and E. pyramidum clades appears to be associated with the opening of the Red Sea. Later land connections between Africa and Arabia may have contributed to shaping the distribution of the E. pyramidum complex. The present distribution of E. carinatus may be the result of range expansion from southern India. Taxonomically, our results provide molecular evidence for the validity of Echis omanensis, E. khosatzkii, E. borkini and E. jogeri, for the presence of unsuspected genetic diversity within the E. pyramidum complex in eastern Africa, and for the conspecificity of E. carinatus and E. multisquamatus. The status of E. leucogaster remains to be confirmed. PMID:19666129

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. Antivenom Effects of 1,2,3-Triazoles against Bothrops jararaca and Lachesis muta Snakes

    PubMed Central

    Domingos, Thaisa F. S.; Moura, Laura de A.; Carvalho, Carla; Campos, Vinícius R.; Jordão, Alessandro K.; Cunha, Anna C.; Ferreira, Vitor F.; de Souza, Maria Cecília B. V.; Sanchez, Eladio F.; Fuly, André L.

    2013-01-01

    Snake venoms are complex mixtures of proteins of both enzymes and nonenzymes, which are responsible for producing several biological effects. Human envenomation by snake bites particularly those of the viperid family induces a complex pathophysiological picture characterized by spectacular changes in hemostasis and frequently hemorrhage is also seen. The present work reports the ability of six of a series of 1,2,3-triazole derivatives to inhibit some pharmacological effects caused by the venoms of Bothrops jararaca and Lachesis muta. In vitro assays showed that these compounds were impaired in a concentration-dependent manner, the fibrinogen or plasma clotting, hemolysis, and proteolysis produced by both venoms. Moreover, these compounds inhibited biological effects in vivo as well. Mice treated with these compounds were fully protected from hemorrhagic lesions caused by such venoms. But, only the B. jararaca edema-inducing activity was neutralized by the triazoles. So the inhibitory effect of triazoles derivatives against some in vitro and in vivo biological assays of snake venoms points to promising aspects that may indicate them as molecular models to improve the production of effective antivenom or to complement antivenom neutralization, especially the local pathological effects, which are partially neutralized by antivenoms. PMID:23710441

  8. Anti-hemorrhagic activity of four Brazilian vegetable species against Bothrops jararaca venom.

    PubMed

    Nishijima, Catarine Massucato Nishijima; Rodrigues, Clenilson Martins; Silva, Marcelo Aparecido; Lopes-Ferreira, Mônica; Vilegas, Wagner; Hiruma-Lima, Clélia Akiko

    2009-01-01

    Around 20,000 snakebites are reported annually in Brazil and 90% of them are inflicted by species of the genus Bothrops. Intravenous administration of antibothropic antivenom neutralizes the systemic actions, but it is of little effect on the reversal of local symptoms and often induces adverse reactions, a context that drives the search for complementary treatments for snakebite accidents. Vegetable extracts with a range of antiophidian activities constitute an excellent alternative. In this study, we investigated the anti-hemorrhagic effects of Mouriri pusa Gardn. (Melastomataceae), Byrsonima crassa Niedenzu (Malpighiaceae), Davilla elliptica St. Hill. (Dilleniaceae) and Strychnos pseudoquina St. Hil. (Loganiaceae) against Bothrops jararaca venom. The methanolic extracts from M. pusa (leaves), B. crassa (leaves) and D. elliptica (leaves) showed total neutralization capacity against local hemorrhages. The amenthoflavone and quercetin fractions from B. crassa and the flavonoids fractions (quercetin and myricetin) from M. pusa and D. elliptica also showed total neutralization capacity. We conclude that flavonoids derived from myricetin, quercetin and amenthoflavone play an important role in the anti-hemorrhagic potential of these Brazilian vegetables species against B. jararaca venom. PMID:19305361

  9. 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)

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 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

  15. 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)

  16. 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.

  17. 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)

  18. A prothrombin activator from Bothrops erythromelas (jararaca-da-seca) snake venom: characterization and molecular cloning.

    PubMed Central

    Silva, Márcia B; Schattner, Mirta; Ramos, Celso R R; Junqueira-de-Azevedo, Inácio L M; Guarnieri, Míriam C; Lazzari, María A; Sampaio, Claudio A M; Pozner, Roberto G; Ventura, Janaina S; Ho, Paulo L; Chudzinski-Tavassi, Ana M

    2003-01-01

    A novel prothrombin activator enzyme, which we have named 'berythractivase', was isolated from Bothrops erythromelas (jararaca-da-seca) snake venom. Berythractivase was purified by a single cation-exchange-chromatography step on a Resource S (Amersham Biosciences) column. The overall purification (31-fold) indicates that berythractivase comprises about 5% of the crude venom. It is a single-chain protein with a molecular mass of 78 kDa. SDS/PAGE of prothrombin after activation by berythractivase showed fragment patterns similar to those generated by group A prothrombin activators, which convert prothrombin into meizothrombin, independent of the prothrombinase complex. Chelating agents, such as EDTA and o -phenanthroline, rapidly inhibited the enzymic activity of berythractivase, like a typical metalloproteinase. Human fibrinogen A alpha-chain was slowly digested only after longer incubation with berythractivase, and no effect on the beta- or gamma-chains was observed. Berythractivase was also capable of triggering endothelial proinflammatory and procoagulant cell responses. von Willebrand factor was released, and the surface expression of both intracellular adhesion molecule-1 and E-selectin was up-regulated by berythractivase in cultured human umbilical-vein endothelial cells. The complete berythractivase cDNA was cloned from a B. erythromelas venom-gland cDNA library. The cDNA sequence possesses 2330 bp and encodes a preproprotein with significant sequence similarity to many other mature metalloproteinases reported from snake venoms. Berythractivase contains metalloproteinase, desintegrin-like and cysteine-rich domains. However, berythractivase did not elicit any haemorrhagic response. These results show that, although the primary structure of berythractivase is related to that of snake-venom haemorrhagic metalloproteinases and functionally similar to group A prothrombin activators, it is a prothrombin activator devoid of haemorrhagic activity. This is a feature not observed for most of the snake venom metalloproteinases, including the group A prothrombin activators. PMID:12225292

  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. 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

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

    PubMed

    Flix-Silva, Juliana; Souza, Thiago; Menezes, Yamara A S; Cabral, Brbara; Cmara, Rafael B G; Silva-Junior, Arnbio 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. 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)

  5. 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

  6. Quantitative and qualitative morphologic, cytochemical and ultrastructural characteristics of blood cells in the Crested Serpent eagle and Shikra.

    PubMed

    Salakij, Chaleow; Kasorndorkbua, Chaiyan; Salakij, Jarernsak; Suwannasaeng, Pimsuda; Jakthong, Pattarapong

    2015-08-01

    The Crested Serpent eagle (Spilornis cheela) is a bird of prey found in the tropical rain forest in Thailand. The Shikra (Accipiter badius) is a sparrow hawk and common resident in Thailand. Blood samples from 9 Crested Serpent eagles and 12 Shikras were obtained from September 2010 to November 2014. They were clinically healthy and negative for blood parasites detectable by light microscopy and molecular techniques (partial cytochrome b gene for avian malaria and partial 18S rRNA gene for trypanosome). Cytochemical staining (Sudan black B, peroxidase, α-naphthyl acetate esterase, and β-glucuronidase) and transmission electron microscopy were performed. Hematological results were reported as the mean ± standard deviation and median. Heterophils were the most prevalent leukocytes in the Crested Serpent eagle, but in the Shikra, lymphocytes were the most prevalent leukocytes. In the Shikra, some vacuoles were observed in the cytoplasm of the eosinophils. All blood cells in both types of raptors stained positively for β-glucuronidase but negatively for peroxidase. The ultrastructure of heterophils showed more clearly differentiate long rod granules in Crested Serpent eagle and spindle-shaped granules in Shikra. The ultrastructure of the eosinophils in the Crested Serpent eagle revealed varied electron-dense, round-shaped granules with round, different electron-dense areas in the centers of some granules, which differed from the structure reported for other raptors. These quantitative results may be useful for clinical evaluations of Crested Serpent eagles and Shikras that are undergoing rehabilitation for release. PMID:26563029

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

    PubMed

    Ćalić, 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

  8. 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

  9. 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 μg) 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

  10. 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

  11. 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.

  12. 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%.

  13. 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.

  14. 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

  15. [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

  16. 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), α and β 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 α and β subunits of CLP of P. chamissonis might have a α-subunit scaffold in common with Viperidae species, whose highly variable C-terminal region might have allowed the diversification in α and β 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

  17. 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

  18. 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

  19. 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

  20. [Cammalanus Railliet and Henry, 1915 (Nematoda, Camallanidae). Parasite from Hydrodynastes gigas (Reptilia, Serpentes, Colubridae) from Argentine Chaco].

    PubMed

    Ramallo, G

    1996-01-01

    Adult specimens of Camallanus genus (Nematoda, Camallanidae), parasitizing a Hydrodynastes gigas (Serpentes, Colubridae) from Chaco in the North East of Argentina, are described for the first time. The morphologic and morphometric parasitological studies were carried out using diaphanization by lactophenol technique. The specimens described were drawn and photographed. With this investigation the analysis of the reptilian pathologies, the knowledge of which is necessary to make projects, to manage and control the biomedic aspects in breeders, zoos and/or reserves has started. Thus, it enables us to know associated nematofauna providing facts about the biodiversity of nematode parasites of reptiles. PMID:9302777

  1. 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)

  2. 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.

  3. 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.

  4. 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

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

    PubMed

    Glaw, Frank; Kucharzewski, Christoph; Khler, Jrn; Vences, Miguel; Nagy, Zoltn T

    2013-01-01

    Herpetological surveys in the dry forests of the limestone massif Montagne des Franais 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 Franais 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

  6. Multiple regulatory safeguards confine the expression of the GATA factor Serpent to the hemocyte primordium within the Drosophila mesoderm.

    PubMed

    Spahn, Philipp; Huelsmann, Sven; Rehorn, Klaus-Peter; Mischke, Stefanie; Mayer, Melanie; Casali, Andreu; Reuter, Rolf

    2014-02-01

    serpent (srp) encodes a GATA-factor that controls various aspects of embryogenesis in Drosophila, such as fatbody development, gut differentiation and hematopoiesis. During hematopoiesis, srp expression is required in the embryonic head mesoderm and the larval lymph gland, the two known hematopoietic tissues of Drosophila, to obtain mature hemocytes. srp expression in the hemocyte primordium is known to depend on snail and buttonhead, but the regulatory complexity that defines the primordium has not been addressed yet. Here, we find that srp is sufficient to transform trunk mesoderm into hemocytes. We identify two disjoint cis-regulatory modules that direct the early expression in the hemocyte primordium and the late expression in mature hemocytes and lymph gland, respectively. During embryonic hematopoiesis, a combination of snail, buttonhead, empty spiracles and even-skipped confines the mesodermal srp expression to the head region. This restriction to the head mesoderm is crucial as ectopic srp in mesodermal precursors interferes with the development of mesodermal derivates and promotes hemocytes and fatbody development. Thus, several genes work in a combined fashion to restrain early srp expression to the head mesoderm in order to prevent expansion of the hemocyte primordium. PMID:24360907

  7. 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.

  8. 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.

  9. 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

  10. Snakes, rotators, serpents and the octahedral group

    SciTech Connect

    Fieguth, T.

    1986-04-01

    Specific configurations of horizontal and vertical bending magnets are given that, when acting on the spin polarization vector of a particle beam, generate a group of 24 operators isomorphic to the group of rotational symmetries of a cube, known as the octahedral group. Some of these configurations have the feature of converting transversely polarized beams to longitudinally polarized beams (or vice versa) at the midpoint of the configuration for, in principle, all beam energies. Since the first order optical transfer matrix for each half of these configurations is nearly that of a drift region, the external geometry remains unchanged and midpoint dispersion is not introduced. Changing field strengths and/or polarities allows a configuration to serve as either a Snake(1/sup st/ or 2/sup nd/ kind) or a Rotator, where in both cases the spin polarization is longitudinal at the midpoint. In this conceptualization, emphasis has been placed on electron beams and, indeed, for these beams some practical applications can be envisioned. However, due to the relatively high integrated field strengths required, application of these concepts to proton beams may be more promising.

  11. 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)

  12. 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

  13. Complete mitochondrial genome of Sinovipera sichuanensis (Reptilia: Squamata: Viperidae).

    PubMed

    Zhu, Fei; Liu, Qin; Zhong, Guanghui; Xiao, Rong; Fang, Min; Guo, Peng

    2016-09-01

    Sinovipera sichuanensis is one of the Asian green pit vipers with less concern. It is endemic to China and only known in Hejiang, Sichuan Province and Jiangkou, Guizhou Province. In this study, we report the complete mitochondrial genome and characterize each partition. The complete mitochondrial genome is 17 225 bp in length containing 2 rRNAs, 13 protein-coding genes, 2 control regions and 22 tRNAs. We use Bayesian Inference (BI) and Maximum Likelihood (ML) methods to infer the phylogenetic relationship of S. sichuanensis. Both BI and ML analyses strongly support that S. sichuanensis is independent from the other two Asian green pit vipers. PMID:26406352

  14. Isolation of protein factors from opossum (Didelphis albiventris) serum which protect against Bothrops jararaca venom.

    PubMed

    Farah, M F; One, M; Novello, J C; Toyama, M H; Perales, J; Moussatché, H; Domont, G B; Oliveira, B; Marangoni, S

    1996-09-01

    The fractionation of Didelphis albiventris serum by DEAE-Sephadex A50 yields a fraction (DA2) which protects the opossum against Bothrops venom. One polypeptide (DA2-II) responsible for this protection was isolated from fraction DA2 by ion exchange chromatography and biochemically characterized. DA2-II is a 43,000 mol. wt glycoprotein with the following N-terminal sequence: LKAMDTTPPLKIKKEPVK. Pairwise comparison of the amino acid sequence with four anti-hemorrhagic factors isolated from other opossum species indicated that DA2-II possesses high similarity (60-80%) with these proteins. PMID:8896201

  15. 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

  16. 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

  17. 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

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

    PubMed

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

    2016-01-01

    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

  19. The rod and the serpent: history's ultimate healing symbol.

    PubMed

    Antoniou, Stavros A; Antoniou, George A; Learney, Robert; Granderath, Frank A; Antoniou, Athanasios I

    2011-01-01

    The snake has served as a medical emblem for more than 2400 years, since its association with the ancient Greek god of medicine and healing, Asclepius, in the 4th century BC. Its symbolic background can be traced further back to the worship of gods of earth's blossom in ancient Egypt and earth-related deities of the archaic period of Greek antiquity. It is featured entwined around a staff of knowledge and wisdom in most anaglyphs depicting Asclepius. The snake was impressed in the Old and the New Testament as well as in the Christian tradition as a symbol of sin, rejuvenation, death, resurrection, asthenia, and therapy. It is postulated that the double-snake motif was reintroduced by Renaissance philosophers as a medical emblem due to the symbolic connections of Hermes with deliverance and redemption. However, its use during the last two centuries seems to lack substantial historical background. The historical, mythological, and traditional retrospection of the snake's symbolism validates its appropriateness in the health-care field. PMID:20556606

  20. 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

  1. 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

  2. The complete mitochondrial genome of Gloydius intermedius (Squamata: Viperidae: Crotalinae) from China.

    PubMed

    Xu, Chunzhu; Zhao, Shuai; Li, Cheng; Dou, Huashan

    2016-07-01

    The mitochondrial genome sequence of Gloydius intermedius is analyzed and presented for the first time. The genome was 17, 226 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 2 control region. The overall base composition was A (32.4%), C (28.8%), T (25.9%), and G (12.9%). The base compositions clearly presented the A-C skew, which was most obvious in the protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of G. intermedius. Mitochondrial genome analyses based on MP, ML, NJ and Bayesian analyses yielded identical phylogenetic trees, indicating a close phylogenetic affinity of the 13 Crotalinae species. It appeared that no less than two major phyletic lineages were present in Crotalinae. The main clades within the Crotalinae supported are: A clade including the Protobothrops. A clade (G. brevicaudus, G. ussuriensis, G. intermedius, G. saxatilis) with the Ovophis appeared as the sister taxon to Protobothrops and was supported by bootstrap values of 88%. The four Gloydius species formed a paraphyletic group with the high bootstrap value (100 %) in all examinations. PMID:26006286

  3. Sequencing and analysis of the complete mitochondrial genome of Gloydius saxatilis (Squamata: Viperidae: Crotalinae).

    PubMed

    Xu, Chunzhu; Xie, Fei; Liu, Yichen; Zhao, Shuai; Wang, Yongsheng; Ma, Teng; Zhao, Tianqing

    2016-07-01

    The mitochondrial genome sequence of Gloydius saxatilis is analyzed and presented for the public for the first time. The genome was 17,218 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 2 control regions. The overall base composition was A (32.3%), C (28.9%), T (25.8%), and G (13.0%). The base compositions presented clearly the A-C skew, which was most obviously in the protein-coding genes. The extended termination-associated sequence domain, the central conserved domain and the conserved sequence block domain are defined in the mitochondrial genome control region of G. saxatilis. Mitochondrial genomes analyses based on MP, ML, NJ and Bayesian analyses yielded identical phylogenetic trees, indicating a close phylogenetic affinity of the thirteen Crotalinae species. It appeared that no less than two major phyletic lineages were present in Crotalinae. The main clades within the Crotalinae supported are: A clade including the Protobothrops. A clade (G. brevicaudus, G. ussuriensis, G. intermedius, G. saxatilis) with the Ovophis as the sister taxon to Protobothrops and was supported by bootstrap values of 88%. The four Gloydius species formed a paraphyletic group with the high bootstrap value (100%) in all examinations. PMID:25806581

  4. 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

  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. 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

  8. 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

  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. 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

  11. 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…

  12. 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

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

    PubMed

    Brischoux, Franois; 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

  14. 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

  15. [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

  16. 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

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

    PubMed

    de Oliveira, Leonardo; da Costa Prudente, Ana Lcia; 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

  18. A phylogenetic analysis of Pseudonaja (Hydrophiinae, Elapidae, Serpentes) based on mitochondrial DNA sequences.

    PubMed

    Skinner, Adam; Donnellan, Stephen C; Hutchinson, Mark N; Hutchinson, Rhonda G

    2005-11-01

    A phylogenetic analysis of mitochondrial ND4 and adjacent tRNA sequences for a geographically extensive series of specimens reveals nine major clades within Pseudonaja, of which six are largely coincident with nominal taxa (P. affinis, P. guttata, P. inframacula, P. ingrami, P. modesta, and P. textilis). The remaining three clades are composed of specimens presently referred to P. nuchalis. Two of these clades correspond with the "Darwin" and "Southern" morphs of previous authors, while the third clade incorporates the "Orange with black head" and "Pale head, grey nape" morphs. We are unable to confirm the presence of consistent karyotypic differences between "Orange with black head" and "Pale head, grey nape" specimens, however, P. inframacula, P. textilis, and P. nuchalis "Darwin" are found to exhibit distinctive karyotypes, as previously reported. These results, in conjunction with additional observations of karyotpic and morphological variation, are consistent with nine historically-independent lineages (i.e., species) within Pseudonaja. There is strong support for a clade composed of P. affinis, P. inframacula, P. ingrami, P. textilis, and the three P. nuchalis lineages, and for the relationships (P. inframacula, P. nuchalis "Southern") and (P. nuchalis "Darwin", P. nuchalis "Orange with black head"--"Pale head, grey nape" ). PMID:16098768

  19. Complex evolution in the Neotropics: the origin and diversification of the widespread genus Leptodeira (Serpentes: Colubridae).

    PubMed

    Daza, Juan M; Smith, Eric N; Páez, Vivian P; Parkinson, Christopher L

    2009-12-01

    Lineage diversification in the Neotropics is an interesting topic in evolutionary biology but is also one of the least understood. The abiotic and biotic complexity of the region precludes generalizations that can be drawn regarding the historical evolutionary processes responsible for the diversity observed. The snake genus Leptodeira provides an excellent opportunity to investigate such processes because it spans the entire Neotropical region. In this study, we infer the phylogenetic position of Leptodeira within Dipsadinae, estimate evolutionary relationships among and within Leptodeira species, and estimate the diversification time and biogeography of the genus. Three mitochondrial gene regions were sequenced for individuals representing all the Leptodeira species and most subspecies currently recognized. Additionally, two nuclear protein-coding gene regions were sequenced for representatives of each species and several genera within the Dipsadinae. We infer that several Leptodeira species are either paraphyletic or polyphyletic as currently recognized, and that most recognized subspecies are not monophyletic lineages. Despite the taxonomic discordance with evolutionary relationships, clades appear to correspond very well to major biogeographic regions of Mexico, Central America and South America. Our results thus highlight the important role of the Miocene and Pliocene for lineage diversification in the Neotropics. Additionally, our time estimates suggest that recent intraspecific phylogeographic structure is likely the result of habitat and climatic fluctuations during the Pleistocene. Cumulatively, our inferences of lineage diversification within Leptodeira suggest a complex evolutionary scenario in the Mexican transition zone and a north to south expansion with a final colonization of the tropics in South America. PMID:19643196

  20. When colour patterns reflect phylogeography: new species of Dasypeltis (Serpentes: Colubridae: Boigini) from West Africa.

    PubMed

    Trape, Sébastien; Mediannikov, Oleg; Trape, Jean-François

    2012-07-01

    Six colour phases are currently known in the genus Dasypeltis in West Africa, three in the D. scabra complex and three in the D. fasciata complex. Molecular phylogenetic analysis reveals that all correspond to distinct species. D. parascabra sp. nov. is described from wet savannah areas of Guinea and Ivory Coast. D. latericia is given full specific rank. The validity of D. sahelensis, D. gansi and D. confusa - three species recently described on the basis of colour pattern and biogeography - is confirmed. D. fasciata is confined to rain forest areas of West and Central Africa. D. scabra is absent from West Africa. PMID:22847016

  1. 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

  2. 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

  3. Ultrastructure and wear patterns of the ventral epidermis of four snake species (Squamata, Serpentes).

    PubMed

    Klein, Marie-Christin G; Gorb, Stanislav N

    2014-10-01

    Snakes are limbless tetrapods highly specialized for sliding locomotion. This locomotion leads to the skin being exposed to friction loads, especially on the ventral body side, which leads to wear. It is presumed that snakes therefore have specific optimizations for minimizing abrasion. Scales from snakes with habitat, locomotor and/or behavior specializations have specific gradients in material properties that may be due to different epidermal architecture. To approach this issue we examined the skin of Lampropeltis getula californiae (terrestrial), Epicrates cenchria cenchria (generalist), Morelia viridis (arboreal), and Gongylophis colubrinus (burrowing) with a focus on (i) the ultrastructure of the ventral epidermis and (ii) the qualitative abrasion pattern of the ventral scales. Scanning and transmission electron microscopy revealed variations in the structure, thickness, layering, and material composition of the epidermis between the species. Furthermore, SEM and white light interferometer images of the scale surface showed that the abrasion patterns differed, even when the snakes were reared on the same substrate. These data support the idea that (i) a specific gradient in material properties may be due to a variation in epidermis architecture (thickness/ultrastructure) and (ii) this variation may be an optimization of material properties for specific ways of life. PMID:25169958

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

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

    PubMed Central

    Brischoux, François; Bonnet, Xavier; Shine, Richard

    2009-01-01

    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

  10. Preliminary Results From the Serpentinite, Extension and Regional Porosity Experiment Across the Nicaraguan Trench (SERPENT)

    NASA Astrophysics Data System (ADS)

    Key, K. W.; Constable, S.; Evans, R. L.; Naif, S.; Matsuno, T.; Lizarralde, D.

    2010-12-01

    Water plays an important role in the volcanic processes occurring at convergent margins, as the release of water from the downgoing slab affects the rheology of the mantle, increases melting by lowering the solidus temperature, and alters the chemistry of arc-lavas. Yet, one of the major uncertainties in terms of fluid inputs into the subduction factory concerns the extent of serpentinization of the oceanic upper mantle and the volumes of water that are being carried into the subduction system through this route. In April 2010 we conducted a large-scale marine electromagnetic experiment along a 300 km profile offshore Nicaragua in a region that shows evidence for substantial fault related fluid circulation in the crust and possibly upper mantle, and high Ba/La ratios and water contents in adjacent onshore volcanics that suggest a strong slab fluid input into the arc-melting. Our project is the largest combined controlled-source electromagnetic (CSEM) and magnetotelluric (MT) data set ever collected on an active subduction zone. During the single 28 day research cruise aboard the R/V Melville we collected 54 stations of broadband marine magnetotelluric (MT) data and deep-towed nearly 800 km of controlled-source electromagnetic (CSEM) data. Robust multiple-station array processing of the MT data yields high quality MT responses from 10 to 20,000 s period. The MT responses are fairly 1D over the abyssal plain, showing the effects of a thin veneer of conductive sediments overlying a resistive lithosphere and a deeper conductive mantle. The responses become strongly 2D on the trench outer rise and exhibit large 3D distortions at the bottom of the trench, likely due to a combination of effects from severe topography and seafloor conductivity variations. Two circular CSEM tows of 30 km radius were measured by special long-wire EM (LEM) sensors on the abyssal plain and the outer rise. The LEM data reveals a distinct pattern of electromagnetic polarization that is characteristic of mantle transverse anisotropy. Since the conductive axis is aligned with the fossil ridge-parallel direction and reactivated normal faults in the trench, we interpret this to be caused by conductive serpentinized mantle penetrating faults. Conventional CSEM data recorded at a broad suite of transmission frequencies along the 300 km long profile and a 50 km along strike profile provide constraints on crustal conductivity variations. The analysis of these data is ongoing and will provide a comprehensive picture of the electrical conductivity structure from the seafloor to the upper mantle, representing the entire input into this part of the Central American subduction system. Since conductivity is highly dependent on thermal structure, crack porosity and the presence of serpentinite, our experiment will provide constraints on the depth of active fluid circulation within the oceanic crust and mantle, the variation of fluid circulation with distance from the trench and hence with the degree of plate bending, and the extent of dewatering of the subducting slab in the shallow portion of the mantle wedge.

  11. 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.

  12. 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…

  13. 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

  14. 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...

  15. 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.

  16. 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

  17. 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

  18. 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

  19. Evolution of rattlesnakes (Viperidae; Crotalus) in the warm deserts of western North America shaped by Neogene vicariance and Quaternary climate change.

    PubMed

    Douglas, Michael E; Douglas, Marlis R; Schuett, Gordon W; Porras, Louis W

    2006-10-01

    During Pleistocene, the Laurentide ice sheet rearranged and diversified biotic distributions in eastern North America, yet had minimal physical impact in western North America where lineage diversification is instead hypothesized to result from climatic changes. If Pleistocene climatic fluctuations impacted desert species, the latter would reflect patterns of restricted gene flow concomitant with indications of demographic bottlenecks. Accordingly, molecular evidence for refugia should be present within these distributions and for subsequent range expansions as conditions improved. We sought answers to these questions by evaluating mitochondrial DNA (mtDNA) sequences from four species of rattlesnakes [Crotalus mitchellii (speckled rattlesnake), Crotalus cerastes (sidewinder), Crotalus tigris (tiger rattlesnake), Crotalus ruber (red diamond rattlesnake)] with distributions restricted to desert regions of southwestern North America. We inferred relationships using parsimony and maximum likelihood, tested intraspecific clades for population expansions, applied an isolation-with-migration model to determine bi-directional migration rates (m) among regions, and inferred divergence times for species and clades by applying a semiparametric penalized likelihood approach to our molecular data. Evidence for significant range expansion was present in two of eight regions in two species (Crotalus mitchellii pyrrhus, C. tigris region north). Two species (C. cerastes, C. mitchellii) showed a distribution concomitant with northward displacement of Baja California from mainland México, followed by vicariant separation into subclades. Effects of Pleistocene climate fluctuations were found in the distributions of all four species. Three regional diversification patterns were identified: (i) shallow genetic diversity that resulted from Pleistocene climatic events (C. tigris, C. ruber); (ii) deep Pleistocene divisions indicating allopatric segregation of subclades within refugia (C. mitchellii, C. cerastes); and (iii) lineage diversifications that extended to Pliocene or Late Miocene (C. mitchellii, C. cerastes). Clade-diversifying and clade-constraining effects impacted the four species of rattlesnakes unequally. We found relatively high levels of molecular diversification in the two most broadly distributed species (C. mitchellii, C. cerastes), and lower levels of genetic diversification in the two species (C. tigris, C. ruber) whose ranges are relatively more restricted. Furthermore, in several cases, the distributions of subspecies were not congruent with our molecular information. We suggest regional conservation perspectives for southwestern deserts cannot rely upon subspecies as biodiversity surrogates, but must instead employ a molecular and deep historical perspective as a primary mechanism to frame biodiversity reserves within this region. PMID:16968275

  20. 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

  1. 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

  2. "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…

  3. 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…

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. Plio-pleistocene diversification and connectivity between mainland and Tasmanian populations of Australian snakes (Drysdalia, Elapidae, Serpentes).

    PubMed

    Dubey, Sylvain; Keogh, J Scott; Shine, Richard

    2010-09-01

    The genus Drysdalia contains three recognised species of elapid (front-fanged) snakes, distributed across south-eastern Australia (including Tasmania). Here we aim to clarify the biogeography and phylogeographical relationships of this poorly documented region. We conducted molecular phylogenetic and dating analyses, using mitochondrial genes (ND4 and cyt-b). Our analyses suggest that divergence events among the three extant species, and among major lineages within those species, are congruent with Plio-pleistocene climatic variations. Two highly divergent genetic lineages within Drysdalia coronoides occur in Tasmania. Molecular dating suggests that these lineages were isolated from the mainland in the Pleistocene. PMID:20430104

  9. 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

  10. 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 horizontal magnetic gradient. Although a source of noise from the perspective of imaging the lithosphere, the motionally induced magnetic fields also present new opportunities for remote sensing in ocean and climate studies.

  11. 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

  12. 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

  13. Lessons Learned from Cosmic Serpent: A Professional Development Project for Informal Educators on Science and Native Ways of Knowing

    NASA Astrophysics Data System (ADS)

    Peticolas, L. M.; Maryboy, N.; Begay, D.; Paglierani, R.; Frappier, R.; Teren, A.

    2011-09-01

    How can one engage native communities and the public alike in understanding nature and our universe? Our approach has been to bring together practitioners at informal science centers, cultural museums, and tribal museums to develop relationships cross-culturally, to learn about different ways of studying and learning about nature and our universe, and to start to develop informal education programs or exhibits at their institution through their new understandings and peer networks. The design of this National Science Foundation (NSF) grant has been to provide an initial week-long professional development workshop in a region in the Western U.S. with a follow-up workshop in that region the following year, culminating in a final conference for all participants. We focus on three regions: the southwest (Utah, Arizona, New Mexico, and Colorado), the northwest (Alaska, Washington, and Oregon); and California. We are in our third year of our four-year grant and have in this time organized and run three regional week-long workshops and a follow-up workshop in the southwest. We have learned many lessons through this work, including: the importance of incorporating workshop participants as presenters in the workshop agenda; how the content of astronomy, ecology, and health resonates with these museum professionals and can easily be discussed with different world views in this type of cross-cultural science education; and how to best present different ways of knowing how nature and our universe work (science) in a manner that provides a context for science educators and museum professionals. In this article, we share these and other lessons we have learned from the leadership perspective of bringing together such a diverse and under-represented-in-science group of educators.

  14. Lessons Learned from Cosmic Serpent, a professional development project for informal educators on science and native ways of knowing

    NASA Astrophysics Data System (ADS)

    Peticolas, L. M.; Maryboy, N.; Begay, D.; Paglierani, R.

    2010-12-01

    How can one engage native communities and the public alike in understanding nature and our universe? Our approach has been to bring together practitioners at informal science centers, cultural museums, and tribal museums to develop relationships cross culturally, learn about different ways of studying and learning about nature and our universe, and start to develop informal education programs or exhibits at their institution through their new understandings and peer networks. The design of the grant has been to provide an initial week-long professional development workshop in a region in the Western U.S. with a follow-up workshop in that region the following year, culminating in a final conference for all participants. We focus on three regions: the southwest (SW - Utah, Arizona, New Mexico and Colorado); the northwest (Alaska, Washington, and Oregon); and California. We are in our fourth year of our four year grant and have in this time organized and run three regional week-long workshops and two follow-up workshops (in the SW and NW). We have learned many lessons through this work, including: the importance of incorporating workshop participants as presenters in the workshop agenda; how the content of astronomy, earth science, ecology, and health resonates with these museum professionals and can easily be discussed with different world views in this type of cross cultural science education; and how to best present different ways of knowing how nature and our universe work (science) in a manner that provides a context for science educators and museum professionals. In our poster presentation, we will share these and other lessons we have learned from the leadership perspective of bringing together such a diverse and under-represented-in-science group of educators.

  15. 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

  16. A perspective on natural products research and ethnopharmacology in Mexico: the eagle and the serpent on the prickly pear cactus.

    PubMed

    Heinrich, Michael; Frei Haller, Barbara; Leonti, Marco

    2014-03-28

    Mexico's extraordinarily rich cultural and floristic diversity has fascinated explorers and researchers ever since the "New World" was discovered for and by Europeans. For many decades, natural product research has been a very active field of research in Mexico, and there also are some ongoing ethnopharmacological research efforts. This review provides an overview and critical appraisal on some key developments in these fields and examples of medicinal plants used by indigenous communities that have become of great local importance in Mexican popular medicine. In this review, the focus is on plants with effects on the CNS, diabetes, metabolic syndrome, inflammatory processes, and gastrointestinal disorders. While some of the major food plants consumed worldwide originate from southern North America, only very few medicinal plants have become of major global importance. Opuntia species are now used increasingly to manage diabetes and metabolic syndrome and represent an example of a novel medicinal product/supplement. Undoubtedly, narcotic and mind-altering drugs both have received the widest scientific interest and have attracted considerable popular attention. The history of use of the indigenous Mexican Materia Medica in the context of research on local and popular resources specifically with regard to the diverse challenges in the context of studying the world's biodiversity and the development of comparative and semiquantitative ethnobotanical research methods is discussed herein. Natural product and ethnopharmacological research in Mexico seems to have been influenced by the political and societal developments originating from the Convention on Biological Diversity (CBD) and subsequent conventions, which have not yet had the desired effect of giving value to these local resources, as they might deserve. Their equitable and sustainable implementation remains a challenge. Natural product research and ethnopharmacology will play a key role in developing an adequate evidence base for such products derived from local and traditional knowledge in Mexico. PMID:24559070

  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. 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

  19. 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

  20. 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

  1. ["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

  2. 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

  3. A new species of Imantodes Duméril, 1853 (Serpentes, Dipsadidae) from the Eastern Cordillera of Colombia.

    PubMed

    Missassi, Alexandre F R; Prudente, Ana L C

    2015-01-01

    We describe a new species of Imantodes, morphologically similar to I. chocoensis, from the Eastern Cordillera of Colombia. This new species is distinguished from all congeners by the following combination of morphological characters: smooth dorsal scale rows 17/17/15; apical pits absent; infralabials 12-13; ventrals 227-236; subcaudals 147-148; presence of loreal scale; cloacal plate divided; dark temporal stripe on the suture between the lower edge of temporal scales and upper region of supralabials; dorsum of body light brown with dark brown transversal streaks, weakly evident in lateral view; hemipenis in situ extending to the level of 11th subcaudal and reaches the 10th subcaudal when everted; hemipenis with sulcus spermaticus expanded at the base of capitulum and extending distally. Additionally, we discuss the lateral expansion of the sulcus spermaticus in the new species, similar to that of species of Leptodeira. PMID:26249972

  4. 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

  5. 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

  6. 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

  7. "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

  8. 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

  9. 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

  10. The phylogeny of cobras inferred from mitochondrial DNA sequences: evolution of venom spitting and the phylogeography of the African spitting cobras (Serpentes: Elapidae: Naja nigricollis complex).

    PubMed

    Wüster, Wolfgang; Crookes, Steven; Ineich, Ivan; Mané, Youssouph; Pook, Catharine E; Trape, Jean-François; Broadley, Donald G

    2007-11-01

    We use phylogenetic analysis of 1333 bp of mitochondrial DNA sequence to investigate the phylogeny and historical biogeography of the cobra-like elapid snakes, with special reference to the evolution of spitting and the phylogeography of the African spitting cobras, a radiation widespread in open vegetational formations throughout sub-Saharan Africa. Our results suggest that spitting adaptations appear to have evolved three times in cobras, but alternative scenarios cannot be rejected. The Asiatic Naja are monophyletic and originate from a single colonization of Asia from Africa. The radiation of the African spitting Naja appears to date back to the early Miocene and many speciation events in the group predate the Pliocene expansion of grasslands and the radiation of large grazing mammals in Africa. The cladogenic events in this complex appear to have been triggered by both ecological changes and tectonic events associated with the formation and expansion of the African Rift Valley. Taxonomically, our data confirm the inclusion of Boulengerina and Paranaja within Naja, and reveal a clade of African rainforest cobras including N. melanoleuca, Paranaja multifasciata and Boulengerina that constitutes the sister clade of the African open-formation non-spitting cobras. Naja nigricollis is polyphyletic, and we therefore recognize N. nigricincta as a separate species, more closely related to N. ashei and N. mossambica than to N. nigricollis. PMID:17870616

  11. A new species of Serpentirhabdias Tkach, Kuzmin & Snyder, 2014 (Nematoda: Rhabdiasidae) parasitic in the brown ground snake Atractus major Boulenger (Reptilia: Serpentes: Dipsadidae) in Brazil.

    PubMed

    Kuzmin, Yuriy; Melo, Francisco Tiago de Vasconcelos; dos Santos, Jeannie Nascimento

    2014-10-01

    Serpentirhabdias atracti n. sp. is described based on specimens discovered in the lung of Atractus major Boulenger from Caxiuanã National Forest, Pará, Brazil. The new species is assigned to Serpentirhabdias Tkach, Kuzmin & Snyder, 2014 based on morphological characters (comparatively thin body cuticle without prominent inflations, arrangement of circumoral papillae in two lateral groups, pre-equatorial position of vulva, eggs in uteri at early cleavage stages), as well as because of its parasitism in snakes. The new species is most similar to S. vellardi (Pereira, 1928) due to the absence of lips and buccal capsule, similar body dimensions, and the specificity to dipsadid snakes in Brazil. The two species differ in the shape of the tail (bulbous dilatation in the posterior part followed by a thread-like tail tip present in S. atracti n. sp.), the width of the oesophagus, and the size of the excretory glands. Serpentirhabdias atracti n. sp. is the sixth species of this genus found in the Neotropical Region. PMID:25204597

  12. 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

  13. 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

  14. 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

  15. 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

  16. Recruitment of striatonigral disinhibitory and nigrotectal inhibitory GABAergic pathways during the organization of defensive behavior by mice in a dangerous environment with the venomous snake Bothrops alternatus (Reptilia, Viperidae).

    PubMed

    Almada, Rafael Carvalho; Coimbra, Norberto Cysne

    2015-06-01

    The neuropsychopharmacological basis of fear- or panic-related behavior has been the focus of several studies. Some mesencephalic tectum (MT) structures, such as the superior colliculus (SC) and dorsal periaqueductal gray matter (dPAG), are considered to be responsible for the control of defensive responses evoked during threatening situations. Furthermore, the pars reticulata of the substantia nigra (SNpr) sends inputs to the SC that can work as a sensory channel to MT neurons fundamental for the elaboration of defensive responses. The purpose of the present study was to investigate the role of striato-nigral GABAergic inputs in the activity of nigro-tectal outputs during the elaboration of defensive behavior using a GABA(A) receptor selective blockade in the MT of mice confronted pre-treated with Bothrops alternatus. Mice with injections of physiological saline into the SNpr and treated with a GABA(A) receptor selective antagonist in the MT displayed an increase in panic-related behavior, expressed by an increase in the duration of freezing, frequency of nonoriented escape and frequency of total escape responses during the confrontation with the snake. However, intra-SNpr injections of cobalt chloride followed by MT injections of bicuculline caused a significant decrease in the duration of freezing and total escape responses. In addition, intra-SNpr injections of lidocaine followed by MT injections of bicuculline caused an increase in panic-related behavior. The results highlight the involvement of SNpr and MT structures in the organization of defensive behaviors and suggest an inhibitory control of striatonigral-nigrotectal pathways during the elaboration of fear- and panic-related behavior. PMID:25727065

  17. 77 FR 70457 - Endangered Species; Marine Mammals; Receipt of Applications for Permit

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

    ... Departments and Agencies of January 21, 2009--Transparency and Open Government (74 FR 4685; January 26, 2009... Varanidae Viperidae (includes Crotalus unicolor but not Crotalus willardi) Species: Grand Cayman blue...

  18. 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.

  19. Geophysics could explain Ancient Maya Myth

    NASA Astrophysics Data System (ADS)

    Bruchez, Margaret Sabom

    According to Maya mythology, the splendor of the principal entity, the Feathered Serpent, is exalted at Lake Atitlán in southwestern Guatemala. A chance look at a phenomenon in the natural environment reveals the possible geophysical basis of this myth.More than poetic fancy, the flight of the Feathered Serpent could refer to the dissipation of a soliton wave formed in the 130-km2 caldera lake. In the myth, recounted in the sixteenth century document los anales de los caqchiqueles, the newly acceded leader of the Kaqchikel-speaking Maya tribe rises from the lake transformed as the Feathered Serpent [Recinos and Goetz, 1953, p. 76]. Residents claim a gigantic serpent, Xocomil, still lives in the waters.

  20. Geophysics Could Explain Ancient Maya Myth

    NASA Astrophysics Data System (ADS)

    Sabom Bruchez, Margaret

    2005-03-01

    According to Maya mythology, the splendor of the principal entity, the Feathered Serpent, is exalted at Lake Atitlán in southwestern Guatemala. A chance look at a phenomenon in the natural environment reveals the possible geophysical basis of this myth. More than poetic fancy, the flight of the Feathered Serpent could refer to the dissipation of a soliton wave formed in the 130-km2 caldera lake. In the myth, recounted in the sixteenth century document los anales de los caqchiqueles, the newly acceded leader of the Kaqchikel-speaking Maya tribe rises from the lake transformed as the Feathered Serpent [Recinos and Goetz, 1953, p. 76]. Residents claim a gigantic serpent, Xocomil, still lives in the waters.

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. 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)

  6. Interior view, detail view of the balustrade; the balustrade is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view, detail view of the balustrade; the balustrade is cast bronze and consists of two ribbed posts alternating with a single post decorated with twisted serpents - New Post Office Building, Twelfth Street and Pennsylvania Avenue, Washington, District of Columbia, DC

  7. 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.

  8. 78 FR 14539 - Notice of Receipt of Pesticide Products; Registration Applications To Register New Uses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-06

    ... azarole, Chinese quince, Japanese quince, medlar, tejocote including cultivars, varieties, and/or hybrids... (bulb), garlic (bulbs of common, great-headed, serpent), lily (bulb), onion (bulbs of common, Chinese... subgroup 3-07B including Chinese chive (fresh leaves), chive (fresh leaves), elegans hosta,...

  9. 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

  10. Proteome-derived peptide library for the elucidation of the cleavage specificity of HF3, a snake venom metalloproteinase.

    PubMed

    Bertholim, Luciana; Zelanis, André; Oliveira, Ana K; Serrano, Solange M T

    2016-05-01

    The Proteomic Identification of Cleavage Sites (PICS) approach was employed for profiling the substrate specificity of HF3, a hemorrhagic snake venom metalloproteinase (SVMP) from Bothrops jararaca. A tryptic peptide library from human plasma was subject to HF3 cleavage and amino acid occurrence for P6 to P6' sites was mapped. 71 cleavage sites were detected and revealed a clear preference for leucine at P1' position, followed by hydrophobic residues in P2'. PICS confirmed existing data on prime site specificity of SVMPs. PMID:27020778

  11. 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

  12. Reference toxins for antivenin standardization*

    PubMed Central

    Schöttler, W. H. A.

    1958-01-01

    Potency determinations in mice of venom samples from snakes of the species Bothrops jararaca, which had been caught in an area of less than 10 000 km2, gave the following principal results: (1) Various methods of drying—i.e., closed and continuous vacuum-drying at 5° and 37°C and freeze-drying (lyophilization)—had no different effect on the potency of venoms. (2) Venom samples which display no differences in the final results of intravenous assay may be distinguishable if the observation time is limited to one or two hours. (3) Venom samples obtained from snakes caught no more than about 50 km apart may be of different potencies. (4) Different titres may be obtained for an antivenin, if different samples of venom from the same snake species are employed as reference preparations in the assay. From physiological experiments on dogs and rabbits, in conjunction with observations made in tests on mice, it is evident that B. jararaca venom causes death in circulatory collapse through a mechanism which is as yet unknown. Two physiologically (and probably immunologically) distinct hypotensory factors seem to be present in this venom. The conclusions drawn from the investigation is that consistent and reproducible reference preparations of snake venoms for antivenin assay can probably be obtained only from snakes that are bred and kept in captivity under constant environmental conditions. PMID:13585080

  13. Does the Jet Stream Indicate the Presence of Transient EMFs also Detected by Native American Environmental Scientists? These Variable EMFs May Impact Regional Power Failures.

    NASA Astrophysics Data System (ADS)

    Pawa Matagamon, Sagamo; Balam Matagmaon, Chan

    2003-10-01

    Ohios Serpent Mound, and other instruments like a schist-like-slate serpent effigy may be monitors that detect transient and periodic electromagnetic field (EMF) effects. Physics courses show that ionic beams transversely entering magnetic fields are deflected at constant velocity into circular paths. Our abstracts of earlier APS/AAPT meetings used this analysis as the basis for tornado and hurricane modeling. Ionized jet streams will be deflected if they penetrate a new, transient region of magnetic fields. Clockwise horizontal deflection of a positively ionized jet stream requires this time-varying magnetic field to be directed perpendicularly away from the earth. One model is that a north magnetic field from a secondary magnetic dipole acts within an anthropomorphized Mother Earth, (M E). Power grid failures are influenced by M Es predictable voltages superposed onto grid frequencies via Faradays Law! Mayan youth and rulers seem to have detected the equivalent.

  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. 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)

  17. Venomous snakebite in Thailand. II: Clinical experience.

    PubMed

    Pochanugool, C; Wildde, H; Bhanganada, K; Chanhome, L; Cox, M J; Chaiyabutr, N; Sitprija, V

    1998-05-01

    We reviewed a total of 2,525 snakebite patients in Bangkok. Of these, 1,415 were bitten by venomous snakes, 91 by neurotoxic snakes of genus Naja or Bungarus and 1,324 by snakes of family Viperidae or Crotalidae. Seventy-one percent of bites were on the lower extremity. There were two fatal cobra bites; both patients were dead on arrival at the hospital. Bites from vipers caused morbidity but no deaths. Species-specific antivenins are effective in reversing respiratory failure from cobra bites and coagulopathies from bites by Viperidae and Crotalidae snakes. However, early respiratory and wound care will save lives even in the absence of specific cobra and krait antivenin. Care of a snakebite victim should consist of immobilization and bandaging of the bitten limb with elastic bandages during transport to the hospital, early surgical debridement of necrotic tissue, appropriate infusion of antivenin, aggressive respiratory support, management of shock and infection, and peritoneal dialysis or hemodialysis. Incision of bite wounds, suctioning, application of ice, and tourniquets are of no proven value and may be dangerous. All snakebite victims in southeast Asia should survive if they receive early competent care. PMID:9597849

  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. 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

  20. Structure and Function of Snake Venom Proteins Affecting Platelet Plug Formation

    PubMed Central

    Matsui, Taei; Hamako, Jiharu; Titani, Koiti

    2009-01-01

    Many snake venom proteins have been isolated that affect platelet plug formation by interacting either with platelet integrins, membrane glycoprotein Ib (GPIb), or plasma von Willebrand factor (VWF). Among them, disintegrins purified from various snake venoms are strong inhibitors of platelet aggregation. Botrocetin and bitiscetin derived from Bothrops jararaca and Bitis arietans venom, respectively, induce VWF-dependent platelet agglutination in vitro. Several GPIb-binding proteins have also been isolated from snake venoms. In this review, we focus on the structure and function of those snake venom proteins that influence platelet plug formation. These proteins are potentially useful as reagents for the sub-diagnosis of platelet disorder or von Willebrand disease, as well as for clinical and basic research of thrombosis and hemostasis. PMID:22069544

  1. Immunological studies on BaH1 and BaP1, two hemorrhagic metalloproteinases from the venom of the snake Bothrops asper.

    PubMed

    Rucavado, A; Borkow, G; Ovadia, M; Gutiérrez, J M

    1995-08-01

    No immunological cross-reactivity was observed between BaH1 and BaP1, two hemorrhagic metalloproteinases isolated from B. asper venom, by gel immunodiffusion, Western blotting and neutralization studies. Cross-reactivity was detected with antisera against these toxins in several crotaline and viperine snake venoms by ELISA, whereas no reactivity was observed with either antiserum against the venoms of Bothrops nummifer, Crotalus durissus terrificus, Vipera russelli and several elapid venoms. Antiserum against native BaH1 neutralized hemorrhagic activity of the venoms of B. asper, B. atrox, B. jararaca, Crotalus atrox, C. durissus durissus, Echis carinatus and Trimeresurus flavoviridis, being ineffective against the venoms of Agkistrodon bilineatus and Lachesis muta. PMID:8533144

  2. Molecular diversity of snake venom nerve growth factors.

    PubMed

    Trummal, Katrin; Tõnismägi, Külli; Paalme, Viiu; Järvekülg, Lilian; Siigur, Jüri; Siigur, Ene

    2011-09-15

    Nerve growth factor (NGF) is a protein which stimulates the differentiation and maintenance of sympathetic and embryonic sensory neurons. Snake venoms are a rich source of NGF. Due to small quantities it is sometimes difficult and laborious to isolate NGF from the venoms. In this study the use of Ni-NTA-agarose for isolation of NGF is studied. Anti-Vipera lebetina NGF antibodies were used for identification of NGF during Ni-NTA-agarose fractionation as well as for cross-reaction studies with 21 snake venoms. All studied venoms contained NGF. The molecular masses of the NGFs from Echis ocellatus, Agkistrodon contortrix contortrix, A. bilineatus, A. blomhoffii, A. saxatilis, Calloselasma rhodostoma, Bothrops jararaca and B. lanceolatus were determined for the first time. Some previous results of the NGF studies are revaluated. PMID:21801740

  3. 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

  4. High-level expression, purification, characterization and structural prediction of a snake venom metalloproteinase inhibitor in Pichia pastoris.

    PubMed

    Shi, Yi; Ji, Ming-Kai; Xu, Jian-Wen; Lin, Xu; Lin, Jian-Yin

    2012-03-01

    Snake venom metalloproteinase inhibitor BJ46a is from the serum of the venomous snake Bothrops jararaca. It has been proven to possess the capacity to inhibit matrix metalloproteinases (MMPs), likely based on its structural similarity to MMPs. This report describes the successful expression, purification, and characterization of the recombinant protein BJ46a in Pichia pastoris. Purified recombinant protein BJ46a was found to inhibit MMPs. Structural modeling was completed and should provide the foundation for further functional research. To our knowledge, this is the first report on the large scale expression of BJ46a, and it provides promise as a method for generation of BJ46a and investigation of its potential use as a new drug for treatment of antitumor invasion and metastasis. PMID:22307654

  5. 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

  6. BJ46a, a snake venom metalloproteinase inhibitor. Isolation, characterization, cloning and insights into its mechanism of action.

    PubMed

    Valente, R H; Dragulev, B; Perales, J; Fox, J W; Domont, G B

    2001-05-01

    Fractionation of the serum of the venomous snake Bothrops jararaca with (NH4)2SO4, followed by phenyl-Sepharose and C4-reversed phase chromatographies, resulted in the isolation of the anti-hemorrhagic factor BJ46a. BJ46a is a potent inhibitor of the SVMPs atrolysin C (class P-I) and jararhagin (P-III) proteolytic activities and B. jararaca venom hemorrhagic activity. The single-chain, acidic (pI 4.55) glycoprotein has a molecular mass of 46 101 atomic mass units determined by MALDI-TOF MS and 79 kDa by gel filtration and dynamic laser light scattering, suggesting a homodimeric structure. mRNA was isolated from the liver of one specimen and transcribed into cDNA. The cDNA pool was amplified by PCR, cloned into a specific vector and used to transform competent cells. Clones containing the complete coding sequence for BJ46a were isolated. The deduced protein sequence was in complete agreement with peptide sequences obtained by Edman degradation. BJ46a is a 322-amino-acid protein containing four putative N-glycosylation sites. It is homologous to the proteinase inhibitor HSF (member of the fetuin family, cystatin superfamily) isolated from the serum of the snake Trimeresurus flavoviridis, having 85% sequence identity. This is the first report of a complete cDNA sequence for an endogenous inhibitor of snake venom metalloproteinases (SVMPs). The sequence reveals that the only proteolytic processing required to obtain the mature protein is the cleavage of the signal peptide. Gel filtration analyses of the inhibitory complexes indicate that inhibition occurs by formation of a noncovalent complex between BJ46a and the proteinases at their metalloproteinase domains. Furthermore, the data shows that the stoichiometry involved in this interaction is of one inhibitor monomer to two enzyme molecules, suggesting an interesting mechanism of metalloproteinase inhibition. PMID:11358523

  7. 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

  8. 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

  9. [A survey on the venomous snakes of the vicinity of Kindia (Guinea) and considerations on the treatment of snakebite].

    PubMed

    Baldé, M C; Mané, Y; Trape, J F

    2009-02-01

    Between June and December 2004, snake collections were undertaken in eight villages of the vicinity of Kindia, an area of Guinea Conakry where the incidence of snakebite is among the highest reported in the world. A total of 916 specimens were collected, including 90 Elapidae (9.8 %) and 174 Viperidae (19.0%). The Black Mamba Dendroaspis polylepis was represented by eight specimens, i.e. almost 1% of the snakes collected. This species, which is considered as very rare in West Africa, appears common in this area of Guinea. The current difficulties for the treatment of snakebite due to the high increase of the cost of antivenom therapy are discussed. PMID:19499730

  10. [Snake envenomation in French Guiana].

    PubMed

    Chippaux, J P

    2002-01-01

    French Guiana is a French Overseas Department in South America. Ninety-five percent of the territory is a tropical rainforest. Its rich fauna includes seven families of snakes but only 3 are potentially venomous. Less than 12% of species and, depending on biotope, 10 to 30% of specimens collected are dangerous for humans. The annual incidence of snakebite is less than 50 bites per 100,000 inhabitants overall but increases to 600 per 100,000 for persons active in the rainforest where the risk is highest. The most common envenomation by Viperidae such as Bothrops, which is abundant throughout French Guiana, induces inflammation, necrosis and hemorrhage. Crotalus durissus, a rattlesnake living in coastal savannah, or Micrurus sp cause neuromuscular poisoning. Coral snakes are encountered throughout French Guiana, but envenomation is very rare. Antivenom therapy must be administered by the intravenous route in association with symptomatic treatment and, if necessary, resuscitation in a specialized care unit. PMID:12192717

  11. Venomous snakebites.

    PubMed

    Adukauskienė, Dalia; Varanauskienė, Eglė; Adukauskaitė, Agnė

    2011-01-01

    More than 5 million people are bitten by venomous snakes annually and more than 100,000 of them die. In Europe, one person dies due to envenomation every 3 years. There is only one venomous snake species in Lithuania--the common adder (Vipera berus)--which belongs to the Viperidae family; however, there are some exotic poisonous snakes in the zoos and private collections, such as those belonging to the Elapidae family (cobras, mambas, coral snakes, etc.) and the Crotalidae subfamily of the Viperidae family (pit vipers, such as rattlesnakes). Snake venom can be classified into hemotoxic, neurotoxic, necrotoxic, cardiotoxic, and nephrotoxic according to the different predominant effects depending on the family (i.e., venom of Crotalidae and Viperidae snakes is more hemotoxic and necrotoxic, whereas venom of Elapidae family is mainly neurotoxic). The intoxication degree is estimated according to the appearance of these symptoms: 1) no intoxication ("dry" bite); 2) mild intoxication (local edema and pain); 3) moderate intoxication (pain, edema spreading out of the bite zone, and systemic signs); 4) severe intoxication (shock, severe coagulopathy, and massive edemas). This topic is relevant because people tend to make major mistakes providing first aid (e.g., mouth suction, wound incision, and application of ice or heat). Therefore, this article presents the essential tips on how first aid should be performed properly according to the "Guidelines for the Management of Snake-Bites" by the World Health Organization (2010). Firstly, the victim should be reassured. Rings or other things must be removed preventing constriction of the swelling limb. Airway/breathing must be maintained. The bitten limb should be immobilized and kept below heart level to prevent venom absorption and systemic spread. Usage of pressure bandage is controversial since people usually apply it improperly. Incision, mouth suction, or excision should not be performed; neither a tourniquet nor ice or heat should be applied. A doctor must monitor respiratory rate, blood pressure, heart rate, renal function, fluid balance, and coagulation status. The only specific treatment method is antivenin--serum with antibodies against antigens of snake venom. Antivenins against pit vipers used in the United States are Antivenin Crotalidae Polyvalent (ACP) and a more purified and hence causing less adverse reactions--Crotalidae Polyvalent Immune Fab (CroFab). In Europe, a polyvalent antiserum against Viperidae family snakes (including the common adder) can be used. Antivenins often may cause severe hypersensitivity reactions because of their protein nature. The bite of the common adder (the only poisonous snake in such countries as Lithuania and Great Britain) relatively rarely results in death; thus, considering the risk of dangerous reactions the antivenin causes itself, the usage of it is recommended to be limited only to life-threatening conditions. PMID:22123554

  12. 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

  13. Inhibitory effect of tea polyphenols on local tissue damage induced by snake venoms.

    PubMed

    Pithayanukul, P; Leanpolchareanchai, J; Bavovada, R

    2010-01-01

    The methanolic extract of fresh tea leaves of Camellia sinensis L. (Theaceae) (CS) was assayed for its potential to inhibit enzymes with hydrolytic activity in Naja naja kaouthia Lesson (Elapidae) and Calloselasma rhodostoma Kuhl (Viperidae) venoms. These snake venom enzymes are responsible for the early effects of envenomation, such as local tissue damage and inflammation. The CS extract inhibited phospholipase A(2), proteases, hyaluronidase and L-amino acid oxidase in both venoms by in vitro neutralization and inhibited the hemorrhagic and the dermonecrotic activities of the venoms in vivo. It is suggested that the inhibitory potential of the CS extract against local tissue damage induced by snake venoms may be attributed to complexation and chelation between the venom proteins and the phenolic contents of the extract. PMID:19585481

  14. 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

  15. The phylogeny and classification of caenophidian snakes inferred from seven nuclear protein-coding genes.

    PubMed

    Vidal, Nicolas; Delmas, Anne-Sophie; David, Patrick; Cruaud, Corinne; Couloux, Arnaud; Hedges, S Blair

    2007-02-01

    More than 80% of the approximately 3000 living species of snakes are placed in the taxon Caenophidia (advanced snakes), a group that includes the families Acrochordidae, Viperidae, Elapidae, Atractaspididae, and the paraphyletic 'Colubridae'. Previous studies using DNA sequences have involved few nuclear genes (one or two). Several nodes have therefore proven difficult to resolve with statistical significance. Here, we investigated the higher-level relationships of caenophidian snakes with seven nuclear protein-coding genes and obtained a well-supported topology. Accordingly, some adjustments to the current classification of Caenophidia are made to better reflect the relationships of the groups. The phylogeny also indicates that, ancestrally, caenophidian snakes are Asian and nocturnal in origin, although living species occur on nearly all continents and are ecologically diverse. PMID:17303545

  16. 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

  17. 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

  18. Snake venom galactoside-binding lectins: a structural and functional overview.

    PubMed

    Sartim, Marco A; Sampaio, Suely V

    2015-01-01

    Snake venom galactoside-binding lectins (SVgalLs) comprise a class of toxins capable of recognizing and interacting with terminal galactoside residues of glycans. In the past 35 years, since the first report on the purification of thrombolectin from Bothrops atrox snake venom, several SVgalLs from Viperidae and Elapidae snake families have been described, as has progressive improvement in the investigation of structural/functional aspects of these lectins. Moreover, the advances of techniques applied in protein-carbohydrate recognition have provided important approaches in order to screen for possible biological targets. The present review describes the efforts over the past 35 years to elucidate SVgalLs, highlighting their structure and carbohydrate recognition function involved in envenomation pathophysiology and potential biomedical applications. PMID:26413085

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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)

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. Transcriptome analysis of the Amazonian viper Bothrops atrox venom gland using expressed sequence tags (ESTs).

    PubMed

    Neiva, Márcia; Arraes, Fabricio B M; de Souza, Jonso Vieira; Rádis-Baptista, Gandhi; Prieto da Silva, Alvaro R B; Walter, Maria Emilia M T; Brigido, Marcelo de Macedo; Yamane, Tetsuo; López-Lozano, Jorge Luiz; Astolfi-Filho, Spartaco

    2009-03-15

    Bothrops atrox is a highly dangerous pit viper in the Brazilian Amazon region. We produced a global catalogue of gene transcripts to identify the main toxin and other protein families present in the B. atrox venom gland. We prepared a directional cDNA library, from which a set of 610 high quality expressed sequence tags (ESTs) were generated by bioinformatics processing. Our data indicated a predominance of transcripts encoding mainly metalloproteinases (59% of the toxins). The expression pattern of the B. atrox venom was similar to Bothrops insularis, Bothrops jararaca and Bothrops jararacussu in terms of toxin type, although some differences were observed. B. atrox showed a higher amount of the PIII class of metalloproteinases which correlates well with the observed intense hemorrhagic action of its toxin. Also, the PLA2 content was the second highest in this sample compared to the other three Bothrops transcriptomes. To our knowledge, this work is the first transcriptome analysis of an Amazonian rain forest pit viper and it will contribute to the body of knowledge regarding the gene diversity of the venom gland of members of the Bothrops genus. Moreover, our results can be used for future studies with other snake species from the Amazon region to investigate differences in gene patterns or phylogenetic relationships. PMID:19708221

  14. Complete amino-acid sequence, crystallization and preliminary X-ray diffraction studies of leucurolysin-a, a nonhaemorrhagic metalloproteinase from Bothrops leucurus snake venom

    PubMed Central

    Ferreira, Rodrigo Novaes; Rates, Breno; Richardson, Michael; Guimarães, Beatriz Gomes; Sanchez, Eládio Oswaldo Flores; de Castro Pimenta, Adriano Monteiro; Nagem, Ronaldo Alves Pinto

    2009-01-01

    Leucurolysin-a (leuc-a) is a class P-I snake-venom metalloproteinase isolated from the venom of the South American snake Bothrops leucurus (white-tailed jararaca). The mature protein is composed of 202 amino-acid residues in a single polypeptide chain. It contains a blocked N-terminus and is not glycosylated. In vitro studies revealed that leuc-a dissolves clots made either from purified fibrinogen or from whole blood. Unlike some other venom fibrinolytic metalloproteinases, leuc-a has no haemorrhagic activity. Leuc-a was sequenced and was crystallized using the hanging-drop vapour-diffusion technique. Crystals were obtained using PEG 6000 or PEG 1500. Diffraction data to 1.80 and 1.60 Å resolution were collected from two crystals (free enzyme and the endogenous ligand–protein complex, respectively). They both belonged to space group P212121, with very similar unit-cell parameters (a = 44.0, b = 56.2, c = 76.3 Å for the free-enzyme crystal). PMID:19652343

  15. Molecular cloning and expression of catrocollastatin, a snake-venom protein from Crotalus atrox (western diamondback rattlesnake) which inhibits platelet adhesion to collagen.

    PubMed Central

    Zhou, Q; Smith, J B; Grossman, M H

    1995-01-01

    A 50 kDa protein that inhibits platelet adhesion to collagen has been isolated from snake venom of Crotalus atrox (western diamondback rattlesnake) and has been named 'catrocollastatin'. The cDNA cloning of catrocollastatin has been accomplished. A full-length cDNA of 2310 bp with an open reading frame between nucleotides 51 and 1880 was obtained. The deduced amino acid sequence consists of 609 amino acids. The cDNA-predicted amino acid sequence is highly similar to that of haemorrhagic metalloproteinase jararhagin from Bothrops jararaca venom, HR1B from Trimeresurus flavoviridis, Ht-e from C. atrox and trigramin from T. gramineus. Like jararhagin and HR1B, catrocollastatin is a multidomain molecule composed of an N-terminal domain, a metalloproteinase domain, a disintegrin-like domain and a cysteine-rich C-terminal domain. In the disintegrin-like domain, the frequently seen RGD (Arg-Gly-Asp) sequence is replaced by SECD (Ser-Glu-Cys-Asp). This cDNA was expressed in Spodoptera frugiperda (fall armyworm) (Sf9) insect cells using a baculovirus expression system. Like native catrocollastatin, the expressed protein is capable of selectively blocking collagen-induced platelet aggregation. This is the first full-length clone of a high-molecular-mass haemorrhagin to be expressed. Images Figure 1 Figure 4 PMID:7733877

  16. 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

  17. 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

  18. Pioneers of anti-venomous serotherapy: Dr Vital Brazil (1865-1950).

    PubMed

    Hawgood, B J

    1992-01-01

    Dr Vital Brazil was a great humanitarian and pioneer of medical science. His main work arose from his concern with poisonous snakebite accidents to labourers working the land. Vital Brazil estimated that, at the beginning of this century, deaths due to crotaline snakebites in the State of São Paulo, Brazil, were nearly 3000 per year, representing a mortality rate of about 25%, the majority being due to bothropic envenomation. After reading a report of Calmette's anti-Naja serum, Vital Brazil raised monovalent serum against the venom of Bothrops jararaca and the venom of Crotalus durissus terrificus. In 1989 this led to the first demonstration of the specificity of anti-venomous serum and later, the first production of polyvalent serum for therapeutic use. As Director of the newly founded Institute Butantan in São Paulo, Vital Brazil was actively engaged in every aspect of serotherapeutic treatment. This included organizing a unique system of exchanging anti-ophidic serum for snakes as well as a wide-ranging teaching programme. His many outstanding contributions to the fields of immunology, public health, toxinology and herpetology required not only a very high level of observational, deductive and practical ability but also an unswerving vision and sense of duty; this was allied to great administrative skill and exceptional energy. PMID:1519249

  19. The anticoagulant effect of Bothrops castelnaudi snake venom (Castelnaud's pit viper).

    PubMed

    Kamiguti, A S; Sousa e Silva, M C; Morena, P; Nahas, L

    1985-01-01

    An inhibitory effect of Bothrops castelnaudi venom was observed on the following systems: prothrombin time, activated partial thromboplastin time, thrombin time, thromboplastin generation time, activation of factor X by Russell's viper venom and Russell's viper venom activated factor X (factor Xa). This effect did not require previous incubation and was prevented by the addition of Bothrops-antivenom. The prolonged activated partial thromboplastin time was not shortened by increased phospholipid concentration (0.5-10 mg/ml), suggesting that the inhibitory effect is not due to an anti-phospholipid activity. No significant fibrinogenolytic activity was detected upon incubation of human fibrinogen with the venom, since physiological levels of thrombin-clottable material were still present. Compared to Bothrops jararaca venom, the proteolytic activity on casein and on azocoll was very low. Thrombin-induced clots of human plasma and fibrinogen were not lysed by the venom within 24 hr. The results indicate that the anticoagulant effect of Bothrops castelnaudi venom is exerted at least at two levels of the blood coagulation mechanism: (1) before prothrombin activation, by inhibiting factor X-activation and factor Xa activity; (2) by direct action on thrombin. PMID:3895581

  20. 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

  1. 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.

  2. Can Portable Technology Capture Subtle Phenomena, Related to Quakes, Hurricanes, Tornados, and Volcanoes, Culturally Reported in the Americas by an Equivalent of ``Kokopelli'' or Ñari Huallac, i.e., the EMF?

    NASA Astrophysics Data System (ADS)

    Ataide, Jade; McLeod, Roger

    2006-03-01

    Peruvians who produced the CD ÑARI HUALAC say this name of their home village represents two of their few original words, meaning ``serpent God.'' Arizona, hurricane, mullah, Molocket, Millinocket and Allagash of Maine, Allahpata, and Apalachicola of FL, and Allegheny of PA are some partial cognates for these ancient words. They are culturally detected aspects of the EMF, like Kokopelli, the ``hunchbacked, flute-playing, dancing around'' icon of our southwest. That aspect of `flutes' indicated by tinnitus, and its co-associated symptoms of Meuniere's syndrome, along with the sensation of `pins and needles', signify the rotation of secondary magnetic poles, stimulating nerve endings with their EMF that technology can detect, here and in Brazil. Can they fool us about some religious concepts?

  3. 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.

  4. Presence of a radioactive gas in archaeological excavations, determination and mitigation.

    PubMed

    Balcázar, M; Gómez, S; Peña, P; Zavala Arredondo, J; Gazzola, J; Villamares, A

    2014-01-01

    During recent archaeological discovery and excavation of a tunnel build approximately 2000 years ago by the Teotihuacans under the feathered serpent temple, in Mexico, abnormal radon concentrations up to 700 Bq m(-3) were measured at several excavation stages. The tunnel is at 15m below the earth surface with a vertical rectangular entrance of 4×4 m(2), a semi cylindrical shape of 3m in diameter, with a probable length of 100 m. This study supports the assumption that at the opening of the tunnel radon concentration was around 5500 Bq m(-3); however, although natural convection in the tunnel atmosphere naturally pups radon out, it build up to a maximum concentration of 2000 Bq m(-3). This paper presents the identification of the radon problem in this archaeological site, dose determination, and the mitigation actions that reduced the radon concentration down to 40 Bq m(-3) that ensure a negligible radon risk for archaeologist. PMID:23938077

  5. 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.

  6. An elastica arm scale

    PubMed Central

    Bosi, F.; Misseroni, D.; Dal Corso, F.; Bigoni, D.

    2014-01-01

    The concept of a ‘deformable arm scale’ (completely different from a traditional rigid arm balance) is theoretically introduced and experimentally validated. The idea is not intuitive, but is the result of nonlinear equilibrium kinematics of rods inducing configurational forces, so that deflection of the arms becomes necessary for equilibrium, which would be impossible for a rigid system. In particular, the rigid arms of usual scales are replaced by a flexible elastic lamina, free to slide in a frictionless and inclined sliding sleeve, which can reach a unique equilibrium configuration when two vertical dead loads are applied. Prototypes designed to demonstrate the feasibility of the system show a high accuracy in the measurement of load within a certain range of use. Finally, we show that the presented results are strongly related to snaking of confined beams, with implications for locomotion of serpents, plumbing and smart oil drilling. PMID:25197248

  7. 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.

  8. 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

  9. Numerous Sinusoidal and Other EMF Phenomena, At Present and Former Native American Sites, May Be Superimposing Themselves onto Regional Power Grids.

    NASA Astrophysics Data System (ADS)

    Cadran, Lawrence R.; Mc Leod, Roger D.; Mc Leod, David M.

    2003-10-01

    Periodic electromagnetic field signals (EMF), sometimes noticeable as faint blue-light or other phenomena, frequently are also detected at sites associated with Native Americans. We first noticed this sort of information in the vicinity of Wendell, MA about fourteen years ago. Similar and other signals are apparent at Americas Stonehenge, AS, in North Salem, NH. Connecticut provided our first evidence of superposition of two such waves at the Gungywamp site north of Groton, CT. A Maine location first showed orthogonally oriented trajectories in neighborhoods formerly frequented by Molocket and Metallak and their relatives near Rumford and Rangeley, ME. Florida exhibits similar signals in the vicinity of Hollywood and at Miamis Tequesta instrument, as does a separate site in CT. Powerful thunderstorms in the vicinity of a stone serpent effigy in Ohio cause EMF pulsations. Such signals are possibly superimposing themselves onto power-grids, where frequency changes and system instabilities may occur, according to the elementary physics involved.

  10. 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.

  11. 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.

  12. Hunter-gatherers and other primates as prey, predators, and competitors of snakes.

    PubMed

    Headland, Thomas N; Greene, Harry W

    2011-12-27

    Relationships between primates and snakes are of widespread interest from anthropological, psychological, and evolutionary perspectives, but surprisingly, little is known about the dangers that serpents have posed to people with prehistoric lifestyles and nonhuman primates. Here, we report ethnographic observations of 120 Philippine Agta Negritos when they were still preliterate hunter-gatherers, among whom 26% of adult males had survived predation attempts by reticulated pythons. Six fatal attacks occurred between 1934 and 1973. Agta ate pythons as well as deer, wild pigs, and monkeys, which are also eaten by pythons, and therefore, the two species were reciprocally prey, predators, and potential competitors. Natural history data document snake predation on tree shrews and 26 species of nonhuman primates as well as many species of primates approaching, mobbing, killing, and sometimes eating snakes. These findings, interpreted within the context of snake and primate phylogenies, corroborate the hypothesis that complex ecological interactions have long characterized our shared evolutionary history. PMID:22160702

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

    PubMed

    Calle, P P; Rivas, J; Muoz, 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. 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

  16. Cytogenetics and molecular data in snakes: a phylogenetic approach.

    PubMed

    Oguiura, N; Ferrarezzi, H; Batistic, R F

    2009-01-01

    Snakes are among the most successful groups of reptiles, numbering about 3,000 extant species. In spite of centuries of comparative anatomical and morphological studies, many aspects of snake systematics remain unsolved. To better understand the evolution and diversity of genomic characteristics in Serpentes, we analyzed online sequence data of mitochondrial and nuclear genes, as well as cytogenetic data and reviewed other genomic characteristics such as toxin genes. After the analysis of the whole-genome and chromosomal organization, we find that: (1) cytogenetic comparisons could provide a useful tool to investigate intergeneric and tribal relationships within the extremely diverse neotropical xenodontine snakes; (2) toxin genes could also help to understand snake evolution if special care is taken to choose the sequences because of the difficulty in avoiding paralogs; (3) snake phylogeny based on mitochondrial genome sequences is largely consistent with the relationship obtained using nuclear genes. PMID:20215738

  17. 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.

  18. [On gods, snakes and staffs--the emblem of the medical profession].

    PubMed

    Rabinerson, David; Salzer, Liat; Gabbay-Benziv, Rinnat

    2014-10-01

    The commonly accepted emblems of the Medical Profession are the staff of the Greek god of medicine--Asklepios (or Asclepius], on which one serpent is entwined. Later, around the 16th century C.E., the wand of the herald of the Greek Gods, e.g., Hermes, on which two snakes are entwined and facing each other, became popular as the emblem of the medical profession. We elaborate on the history of the evolution of these emblems as symbols of medicine, including earlier influences from the times of the ancient Egyptians and Babylonians, which were followed by Judeo-Christian traditions and concepts. The relevance of the use of the wand of Hermes as an emblem of our profession is further discussed. PMID:25518083

  19. Origins of the ancient constellations: I. The Mesopotamian traditions

    NASA Astrophysics Data System (ADS)

    Rogers, J. H.

    1998-02-01

    In the sky-map of ancient Babylon, constellations had two different roles, and thus developed into two overlapping traditions. One set of constellations represented the gods and their symbols; the other set represented rustic activities and provided a farming calendar. Many constellations were shared by the two traditions, but in some regions of sky there were alternative divine and rustic figures. These figures developed in stages from ~3200 BC to ~500 BC. Of the divine set, the most important (although the last to be finalised) were the twelve zodiacal signs, plus several associated animals (the serpent, crow, eagle, and fish), which were all transmitted to the classical Greek sky-map that we still use today. Conversely, the rustic constellations of workers and tools and animals were not transmitted to the West. However, a few of them may have survived in Bedouin Arab sky-maps of the first millennium AD.

  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. 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

  2. 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

  3. 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.

  4. Toward Reanalysis of the Tight-Pitch HCLWR-PROTEUS Phase II Experiments

    NASA Astrophysics Data System (ADS)

    Perret, Grégory; Vlassopoulos, Efstathios; Hursin, Mathieu; Pautz, Andreas

    2016-03-01

    The HCLWR-Proteus Phase II experiments were conducted from 1985 to 1990 in the zero-power reactor Proteus at PSI in Switzerland. The experimental program was dedicated to the physics of high conversion light water reactors and in particular to the measurement of reactor parameters such as reaction rate traverses, spectral indices, absorber reactivity worths and void coefficients. The HCLWR experiments are especially interesting because they generated knowledge in the epithermal range of the neutron flux spectrum, for which little integral experimental data is available. In an effort to assess the interest of this experimental data to validate modern nuclear data and improve their uncertainties, a preliminary re-analysis of selected configurations was conducted with Monte-Carlo codes (MCNP6/SERPENT2) and modern nuclear data libraries (ENDF/B-VII.0, JEFF-3.1.1 and JENDL-4.0). The spectral ndices, flux spectra and sensitivity coefficients on k∞ were calculated using cell models representative of the tight-pitch measurement configurations containing 11% PuO2-UO2 fuel rods in different moderation conditions (air, water and dowtherm). Spectral index predictions using the three nuclear data libraries agreed within two standard deviations with the measured values. The only exception is the Pu-242-capture-to-Pu-239-fission ratio, which was overestimated with all libraries by more than four standard deviations, i.e. 13%, in the non-moderated configuration. In this configuration, Pu-242 captures are few since the flux spectrum in the Pu-242 capture resonance region (between 1eV and 1keV) is small making this spectral index hard to measure. Sensitivity coefficient predictions with both MCNP6 and SERPENT2 were in good agreement.

  5. 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.

  6. 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

  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. 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

  9. 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

  10. '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

  11. Molecular Cloning, Characterization, and Chromosome Mapping of Reptilian Estrogen Receptors

    PubMed Central

    Katsu, Yoshinao; Matsubara, Kazumi; Kohno, Satomi; Matsuda, Yoichi; Toriba, Michihisa; Oka, Kaori; Guillette, Louis J.; Ohta, Yasuhiko; Iguchi, Taisen

    2010-01-01

    In many vertebrates, steroid hormones are essential for ovarian differentiation during a critical developmental stage as well as promoting the growth and differentiation of the adult female reproductive system. Although studies have been extensively conducted in mammals and a few fish, amphibians, and bird species, the molecular mechanisms of sex steroid hormone (estrogens) action have been poorly examined in reptiles. Here, we evaluate hormone receptor and ligand interactions in two species of snake, the Okinawa habu (Protobothrops flavoviridis, Viperidae) and the Japanese four-striped rat snake (Elaphe quadrivirgata, Colubridae) after the isolation of cDNAs encoding estrogen receptor α (ESR1) and estrogen receptor β (ESR2). Using a transient transfection assay with mammalian cells, the transcriptional activity of reptilian (Okinawa habu, Japanese four-striped rat snake, American alligator, and Florida red-belly freshwater turtle) ESR1 and ESR2 was examined. All ESR proteins displayed estrogen-dependent activation of transcription via an estrogen-response element-containing promoter; however, the responsiveness to various estrogens was different. Further, we determined the chromosomal locations of the snake steroid hormone receptor genes. ESR1 and ESR2 genes were localized to the short and long arms of chromosome 1, respectively, whereas androgen receptor was localized to a pair of microchromosomes in the two snake species examined. These data provide basic tools that allow future studies examining receptor-ligand interactions and steroid endocrinology in snakes and also expands our knowledge of sex steroid hormone receptor evolution. PMID:20926589

  12. 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

  13. [Mortality from snake bites, wild and domestic animal bites and arthropod stings in the savannah zone of eastern Senegal].

    PubMed

    Trape, J F; Pison, G; Guyavarch, E; Mane, Y

    2002-08-01

    From 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern Senegal. Of 4,228 deaths registered during this period, 26 were brought on by snakebites, 4 by invertebrate stings and 8 by other wild or domestic animals. The average annual mortality rate from snakebite was 14 deaths per 100,000 population. Among persons aged 1 year or more, 0.9% (26/2,880) of deaths were caused by snakebite and this cause represented 28% (26/94) of the total number of deaths by accident. We also investigated the snake fauna of the area. Of 1,280 snakes belonging to 34 species that were collected, one-third were dangerous and the proportion of Viperidae, Elapidae and Atractaspididae was 23%, 11% and 0.6%, respectively. The saw-scaled viper Echis ocellatus was the most abundant species (13.6%). Other venomous species were Causus maculatus (6.5%), Naja katiensis (5.5%), Bitis arietans (2.7%), Elapsoidea trapei (2.4%), Naja nigricollis (1.2%), Naja melanoleuca (1.1%), Atractaspis aterrima (0.4%), Dendroaspis polylepis (0.3%) and Naja haje (0.1%). PMID:12404858

  14. High mortality from snakebite in south-eastern Senegal.

    PubMed

    Trape, J F; Pison, G; Guyavarch, E; Mane, Y

    2001-01-01

    Over 24 years, from 1976 to 1999, we conducted a prospective study of overall and cause-specific mortality among the population of 42 villages of south-eastern Senegal. Of 4228 deaths registered during this period, 26 were caused by snakebite, 4 by invertebrate stings and 8 by other wild or domestic animals. The average annual mortality rate from snakebite was 14 deaths per 100,000 population. Among persons aged > or = 1 year, 0.9% (26/2880) of deaths were caused by snakebite and this cause represented 28% (26/94) of total deaths by accidents. We also investigated the snake fauna of the area. Of 1280 snakes belonging to 34 species that were collected, one-third were dangerous and the proportion of Viperidae, Elapidae and Atractaspidae was 23%, 11% and 0.6%, respectively. The saw-scaled viper Echis ocellatus was the most abundant species (13.6%). Other venomous species were Causus maculatus (6.5%), Naja katiensis (5.5%), Bitis arietans (2.7%), Elapsoidea trapei (2.4%), Naja nigricollis (1.2%), Naja melanoleuca (1.1%), Atractaspis aterrima (0.4%), Dendroaspis polylepis (0.3%) and Naja haje (0.1%). PMID:11579888

  15. Retrospective review of snake bite victims.

    PubMed

    Nazim, Muhammad H; Gupta, Sanjay; Hashmi, Syed; Zuberi, Jamshed; Wilson, Alison; Roberts, Lawrence; Karimi, Kamran

    2008-01-01

    Venomous snakebites are a rare but dangerous and potentially deadly condition in the U.S.. Most bites in the U. S. result from envenomation with snakes of the family Viperidae, subfamily Crotalinae, which includes rattlesnakes and copperheads. Treatment includes a comprehensive work-up to look for possible hematologic, neurologic, renal, and cardiovascular abnormalities, local wound care, systemic antivenom administration, tetanus prophylaxis, antibiotics in the presence of infection and surgical treatment if needed, which may include debridement, fasciotomy and rarely amputation. All these patients should be observed for a minimum of 8 hours. Any evidence of envenomation mandates a minimum of 24 hours of in-hospital observation. A grading system to classify the severity of envenomation is described. The most commonly used antivenom in the U.S. is CroFab, which has a much lower incidence of acute or delayed allergic reactions compared to the older antivenoms. When allergic reactions do occur, they are usually of mild to moderate severity. With the improved risk-benefit ratio of CroFab, antivenom is indicated with any grade of envenomation. In this a retrospective study, we will review our experience with 25 snakebite victims admitted to the West Virginia University over a five years period. PMID:18846756

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

    PubMed

    Fita, Dídac S; Costa Neto, Eraldo M; Schiavetti, Alexandre

    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

  17. 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 Aα chain quickly and to a lesser extent the Bβ 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 μg/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

  18. Isolation and biochemical characterization of a new thrombin-like serine protease from Bothrops pirajai snake venom.

    PubMed

    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 Cu(2+) 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

  19. 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

  20. 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

  1. 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

  2. Autolysis at the disintegrin domain of patagonfibrase, a metalloproteinase from Philodryas patagoniensis (Patagonia Green Racer; Dipsadidae) venom.

    PubMed

    Peichoto, María E; Paes Leme, Adriana F; Pauletti, Bianca A; Batista, Isabel Correia; Mackessy, Stephen P; Acosta, Ofelia; Santoro, Marcelo L

    2010-09-01

    Patagonfibrase is a 57.5-kDa hemorrhagic metalloproteinase isolated from the venom of Philodryas patagoniensis (Patagonia Green Racer), a South American rear-fanged snake. Herein we demonstrate that patagonfibrase undergoes autolysis at its pH optimum (7.5) and at 37 degrees C, primarily producing a approximately 32.6 kDa fragment composed of disintegrin-like and cysteine-rich domains, as identified by mass spectrometry and N-terminal sequencing. The autolysis site for production of this fragment is similar to that observed for metalloproteinases from front-fanged Viperidae snake venoms. In the presence of Ca(2+), patagonfibrase was only partially autolysed, giving rise mainly to one fragment of approximately 52.2 kDa. In addition, calcium markedly enhanced the azocaseinolytic activity of patagonfibrase. Our findings contribute to the understanding of the structural and mechanistic bases of this family of metalloenzymes that are widely distributed among snake venoms, demonstrating that important post-translational modifications such as proteolysis can also contribute to the diversity and complexity of proteins found in rear-fanged snake venoms. PMID:20538077

  3. 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

  4. 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

  5. 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

  6. 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

  7. Fatal snakebite in Australia.

    PubMed

    White, J; Pounder, D J

    1984-06-01

    More than 20 venomous snakes found in Australia belong to the family Elapidae . Although their venom delivery system is less efficient than that of the Viperidae , their venoms are extremely potent. The active components of Australian elapid venoms include neurotoxins, myotoxins , hemolysins, and factors producing hypocoagulability. The groups at particular risk of snakebite are children, agricultural workers, bushwalkers , and herpetologists . A high index of suspicion must be maintained when investigating cases of sudden unexpected death in these groups. The bite wound itself may be particularly easily overlooked as there is little local reaction to many elapid bites. The necropsy findings in fatalities are predictable from the known properties of the venoms of the various species. However, these findings are non-specific and the diagnosis ultimately rests upon the demonstration of the presence of venom by immunoassay. For this purpose swabs from the bite site, the overlying clothing, the excised bite site, the local and regional lymph nodes, urine, and blood may be used. PMID:6731405

  8. Snake venom phospholipases A2: a new class of antitumor agents.

    PubMed

    Rodrigues, Renata S; Izidoro, Luiz Fernando M; de Oliveira, Robson J; Sampaio, Suely V; Soares, Andreimar M; Rodrigues, Veridiana M

    2009-01-01

    Phospholipases A(2) (PLA(2)) are enzymes of high medical scientific interest due to their involvement in a large number of human inflammatory diseases. PLA(2) constitute a diverse family of enzymes which catalyses the hydrolysis of the sn-2 ester bond in glycerophospholipids and exhibit a wide range of physiological and pathological effects. The ubiquitous nature of PLA(2) highlights the important role they play in many biological processes, as cell signaling and cell growth, including the generation of proinflammatory lipid mediators such as prostaglandin and leukotrienes, regulation of lipid mediators. The activity and expression of several PLA(2) isoforms are increased in several human cancers, suggesting that these enzymes have a central role in both tumor development and progression and can be targets for anti-cancer drugs. On the other hand, some PLA(2) isolated from Viperidae venoms are capable to induce antitumoral activity. In summary PLA(2) from snake venoms can be a new class of anticancer agents and provide new molecular and biological insights of cancer development. PMID:19689415

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. Snake bite in Nigeria.

    PubMed

    Habib, A G; Gebi, U I; Onyemelukwe, G C

    2001-09-01

    Four families of venomous snakes are found in Nigeria--Viperidae, Elapidae, Colubridae and Actraspididae but three species carpet viper (Echis ocellatus), black-necked spitting cobra (Naja nigricollis) and puff adder (Bitis arietans), belonging to the first two families, are the most important snakes associated with envenoming in Nigeria. The incidence of bites has been reported as 497 per 100,000 population per year with a 12 percent natural mortality, with Echis ocellatus accounting for at least 66 percent in certain foci. Bites occur more often while victims were farming, herding or walking although the spitting cobra may bite victims who roll upon it in their sleep. Carpet viper venom contains a prothrombin activating procoagulant, haemorrhagin and cytolytic fractions which cause haemorrhage, incoagulable blood, shock and local reactions/ necrosis. The spitting cobra bite manifests with local tissue reaction and occassionally with bleeding from the site of bite, but no classic neurotoxic feature has been observed except following Egyptian cobra (N. haje) bites. Cardiotoxicity and renal failure may occassionally occur following bites by the carpet viper and the puff adder. In the laboratory, haematological and other features are noted and immunodiagnosis has a role in species identification. Immobilisation of the bitten limb is probably the single most important first aid measure. Antivenom should be used cautiously when indicated. As only 8.5 percent of snake bite victims attend hospitals in Nigeria, health education should be the main preventive measure, mean-while, the study of immunisation of occupationally predisposed individuals in endemic areas should be intensified. A new Fab fragment antivenom specific to Nigerian Echis ocellatus was investigated clinically, just as the local herbs-Aristolochia spp, Guiera spp and Schummaniophyton spp are investigated experimentally. PMID:14510123

  17. Phospholipase A(2) 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 μg/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

  18. 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.

  19. 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

  20. Genetic Identification of Spirometra decipiens Plerocercoids in Terrestrial Snakes from Korea and China

    PubMed Central

    Jeon, Hyeong-Kyu; Park, Hansol; Lee, Dongmin; Choe, Seongjun; Kim, Kyu-Heon; Sohn, Woon-Mok; Eom, Keeseon S.

    2016-01-01

    Human sparganosis is a zoonotic disease caused by infection with larval forms (procercoid/plerocercoid) of Spirometra spp. The purpose of this study was to identify Spirometra spp. of infected snakes using a multiplex PCR assay and phylogenetic analysis of mitochondrial DNA sequence data from the spargana of terrestrial snakes obtained from Korea and China. A total of 283 snakes were obtained that included 4 species of Colubridae comprising Rhabdophis tigrinus tigrinus (n=150), Dinodon rufozonatum rufozonatum (n=64), Elaphe davidi (n=2), and Elaphe schrenkii (n=7), and 1 species of Viperidae, Agkistrodon saxatilis (n=60). The snakes were collected from the provinces of Chungbuk, Chungnam, and Gyeongbuk in Korea (n=161), and from China (n=122). The overall infection rate with spargana was 83% (235/283). The highest was recorded for D. rufozonatum rufozonatum (100%), followed by A. saxatilis (85%) and R. tigrinus tigrinus (80%), with a negative result for E. davidi (0%) and E. schrenkii (0%). The sequence identities between the spargana from snakes (n=50) and Spirometra erinaceieuropaei (KJ599680) or S. decipiens (KJ599679) control specimens were 90.8% and 99.2%, respectively. Pairwise genetic distances between spargana (n=50) and S. decipiens ranged from 0.0080 to 0.0107, while those between spargana and S. erinaceieuropaei ranged from 0.1070 to 0.1096. In this study, all of the 904 spargana analyzed were identified as S. decipiens either by a multiplex PCR assay (n=854) or mitochondrial cox1 sequence analysis (n=50). PMID:27180576

  1. 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

  2. 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

  3. A survey of hemoparasite infections in free-ranging mammals and reptiles in French Guiana.

    PubMed

    de Thoisy, B; Michel, J C; Vogel, I; Vié, J C

    2000-10-01

    Blood smears of 1,353 free-ranging mammals (35 species) and 112 reptiles (31 species) from French Guiana were examined for hemoparasites. Parasites from 3 major groups were recorded: Apicomplexa (including hemogregarines, piroplasms, and Plasmodium spp.), Trypanosomatidae, and Filaroidea. Fifty percent of the individuals (86% of the species) were infected by parasites from at least 1 group. Hemogregarines, identified as Hepatozoon sp., infected numerous snakes with high prevalences (30-100%); infection is reported for the first time in 5 host genera of snakes: Clelia, Oxybelis, Pseustes, Rhinobotryum, and Bothriopsis. Infections were also observed in 4 marsupial species and 1 rodent. Hepatozoon spp. recorded in Didelphis albiventris (Marsupialia) and Coendou prehensilis (Rodentia) may be new species. Plasmodium sp. were observed in 2 snake species, Dipsas indica (Colubridae) and Bothrops atrox (Viperidae). Plasmodium brasilianum was recorded in all 5 primate species examined. Piroplasms were observed in all mammal orders except primates. Large terrestrial rodents were the main hosts of members of the Babesidae; 42% of Myoprocta acouchy, 36% of Dasyprocta agouti, and 44% of Agouti paca were infected. Trypanosomes were common in mammals and were recorded in 70% of the examined genera. Trypanosoma cruzi-like infections were reported in 21 mammal species, including sloths, rodents, carnivores, and primates. Microfilariae were also widespread, with higher prevalences in sloths, anteaters, and porcupines (>40% of the individuals infected) and in tamarins (95% infected). This survey highlights some potential anthropozoonotic risks due to the recent further evidence of Plasmodium brasilianum and P. malariae as a single species and to the increased diversity of hosts for Trypanosoma cruzi. PMID:11128476

  4. 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

  5. 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 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  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. 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.

  13. Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor.

    PubMed

    Feng, Jinfeng; Kang, Xiaoxu; Zuo, Qingyun; Yuan, Chao; Wang, Weijun; Zhao, Yuhang; Zhu, Limin; Lu, Hanwei; Chen, Juying

    2016-01-01

    In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO) was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002) peak at about 10.278°, whereas graphite has (002) peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH) level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product. PMID:26938538

  14. 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

  15. Joseph Clover and the cobra: a tale of snake envenomation and attempted resuscitation with bellows in London, 1852.

    PubMed

    Ball, C

    2010-07-01

    The Industrial Revolution saw the creation of many new jobs, but probably none more curious than that of zookeeper. The London Zoological Gardens, established for members in 1828, was opened to the general public in 1847. In 1852 the "Head Keeper in the Serpent Room", Edward Horatio Girling, spent a night farewelling a friend departing for Australia. He arrived at work in an inebriated state and was bitten on the face by a cobra that he was handling in a less than sensible manner. He was taken by cab to University College Hospital where he was resuscitated by a number of doctors, including Joseph Clover then the resident medical officer to the hospital and later to become the leading anaesthetist in London. Clover recorded this event in his diary along with the resuscitation method used. The patient eventually died but his treatment created a flurry of correspondence in the medical and lay press. Interestingly, the attempted resuscitation was with bellows, which had been abandoned by the Royal Humane Society twenty years earlier Clover records other cases of resuscitation with bellows at University College Hospital during his time as a resident medical officer there (1848 to 1853). There is a casebook belonging to Joseph Clover in the Geoffrey Kaye Museum, in Melbourne. This story is one of the many interesting stories uncovered during a study of this book and Clover's other personal papers. PMID:20715640

  16. 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

  17. 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

  18. 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.

  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. 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

  1. 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).

  2. 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

  3. 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

  4. 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?

  5. 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?

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. Nova Scotia: ``Feu Follet" At Cheticamp, and Also the Phenomena At L'Sitkuk of the Mi'Kmaw, May Be Electromagnetic In Nature.

    NASA Astrophysics Data System (ADS)

    Ochs, Michael Ann; McLeod, Roger D.

    2001-11-01

    There is a strong tradition that ``feu follet" exists at the cemetery associated with the Acadian French at Cheticamp. It is described as a blue light, and may actually be the equivalent of an ascending, positively charged stream of ions in the atmosphere, just like the blue-light column that is often a precursor of a storm's lightning-strike. Similar phenomena are at America's Stonehenge, at a stone serpent effigy site in Ohio, and just north of the Lakes Memphremagog and Magog of Vermont and Canada. At the Bear River L'sitkuk Reservation area, which seems to us to have been a most unsuitable site, was deliberately chosen by the Mi'kmaw for their living area. Was this because certain properties of the electromagnetic field (EMF) are evident to them there, which also seem to be reflected in their legends? We hope to establish that these disparate cultures and their separate worldviews can be confirmed by the presence of particular EMF signatures. *This paper does not represent the views of the United States Environmental Protection Agency.

  12. Micrurus snake venoms activate human complement system and generate anaphylatoxins

    PubMed Central

    2012-01-01

    Background The genus Micrurus, coral snakes (Serpentes, Elapidae), comprises more than 120 species and subspecies distributed from the south United States to the south of South America. Micrurus snake bites can cause death by muscle paralysis and further respiratory arrest within a few hours after envenomation. Clinical observations show mainly neurotoxic symptoms, although other biological activities have also been experimentally observed, including cardiotoxicity, hemolysis, edema and myotoxicity. Results In the present study we have investigated the action of venoms from seven species of snakes from the genus Micrurus on the complement system in in vitro studies. Several of the Micrurus species could consume the classical and/or the lectin pathways, but not the alternative pathway, and C3a, C4a and C5a were generated in sera treated with the venoms as result of this complement activation. Micrurus venoms were also able to directly cleave the α chain of the component C3, but not of the C4, which was inhibited by 1,10 Phenanthroline, suggesting the presence of a C3α chain specific metalloprotease in Micrurus spp venoms. Furthermore, complement activation was in part associated with the cleavage of C1-Inhibitor by protease(s) present in the venoms, which disrupts complement activation control. Conclusion Micrurus venoms can activate the complement system, generating a significant amount of anaphylatoxins, which may assist due to their vasodilatory effects, to enhance the spreading of other venom components during the envenomation process. PMID:22248157

  13. 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)

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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?

  19. Propagation of Nuclear Data Uncertainties for ELECTRA Burn-up Calculations

    NASA Astrophysics Data System (ADS)

    Sjöstrand, H.; Alhassan, E.; Duan, J.; Gustavsson, C.; Koning, A. J.; Pomp, S.; Rochman, D.; Österlund, M.

    2014-04-01

    The European Lead-Cooled Training Reactor (ELECTRA) has been proposed as a training reactor for fast systems within the Swedish nuclear program. It is a low-power fast reactor cooled by pure liquid lead. In this work, we propagate the uncertainties in 239Pu transport data to uncertainties in the fuel inventory of ELECTRA during the reactor lifetime using the Total Monte Carlo approach (TMC). Within the TENDL project, nuclear models input parameters were randomized within their uncertainties and 740 239Pu nuclear data libraries were generated. These libraries are used as inputs to reactor codes, in our case SERPENT, to perform uncertainty analysis of nuclear reactor inventory during burn-up. The uncertainty in the inventory determines uncertainties in: the long-term radio-toxicity, the decay heat, the evolution of reactivity parameters, gas pressure and volatile fission product content. In this work, a methodology called fast TMC is utilized, which reduces the overall calculation time. The uncertainty of some minor actinides were observed to be rather large and therefore their impact on multiple recycling should be investigated further. It was also found that, criticality benchmarks can be used to reduce inventory uncertainties due to nuclear data. Further studies are needed to include fission yield uncertainties, more isotopes, and a larger set of benchmarks.

  20. Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor †

    PubMed Central

    Feng, Jinfeng; Kang, Xiaoxu; Zuo, Qingyun; Yuan, Chao; Wang, Weijun; Zhao, Yuhang; Zhu, Limin; Lu, Hanwei; Chen, Juying

    2016-01-01

    In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO) was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002) peak at about 10.278°, whereas graphite has (002) peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH) level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product. PMID:26938538

  1. Does the Corona Borealis Supercluster form a giant binary-like system?

    NASA Astrophysics Data System (ADS)

    Baiesi Pillastrini, Giovanni C.

    2016-05-01

    The distribution of local gravitational potentials generated by a complete volume-limited sample of galaxy groups and clusters filling the Corona Borealis region has been derived to search for new gravitational hints in the context of clustering analysis unrevealed by alternative methodologies. Mapping such a distribution as a function of spatial positions, the deepest potential wells in the sample trace unambiguously the locations of the densest galaxy cluster clumps providing the physical keys to bring out gravitational features connected to the formation, composition and evolution of the major clustered structures filling that region. As expected, the three deepest potential wells found at Equatorial coordinates: (˜230°, ˜28°, z ˜ 0.075), (˜240°, ˜27°, z ˜ 0.09) and, (227°, 5.8°, z ˜ 0.0788) correspond to massive superclusters of galaxy groups and clusters identified as the Corona Borealis, A2142 and Virgo-Serpent, respectively. However, the deepest isopotential contours around the Corona Borealis and A2142 superclusters seem to suggest a gravitational feature similar to a giant binary-like system connected by a filamentary structure. To a first approximation, it seems unlikely that this hypothesized system could be gravitationally bound.

  2. Combining Total Monte Carlo and Benchmarks for Nuclear Data Uncertainty Propagation on a Lead Fast Reactor's Safety Parameters

    NASA Astrophysics Data System (ADS)

    Alhassan, E.; Sjöstrand, H.; Duan, J.; Gustavsson, C.; Koning, A. J.; Pomp, S.; Rochman, D.; Österlund, M.

    2014-04-01

    Analyses are carried out to assess the impact of nuclear data uncertainties on keff for the European Lead Cooled Training Reactor (ELECTRA) using the Total Monte Carlo method. A large number of 239Pu random ENDF-formatted libraries generated using the TALYS based system were processed into ACE format with NJOY-99.336 code and used as input into the Serpent Monte Carlo neutron transport code to obtain distribution in keff. The mean of the keff distribution obtained was compared with the major nuclear data libraries, JEFF-3.1.1, ENDF/B-VII.1 and JENDL-4.0. A method is proposed for the selection of benchmarks for specific applications using the Total Monte Carlo approach. Finally, an accept/reject criterion was investigated based on χ2 values obtained using the 239Pu Jezebel criticality benchmark. It was observed that nuclear data uncertainties in keff were reduced considerably from 748 to 443 pcm by applying a more rigid acceptance criteria for accepting random files.

  3. Emergence of undulatory magnetic flux tubes by small scale reconnections

    NASA Astrophysics Data System (ADS)

    Pariat, E.; Aulanier, G.; Schmieder, B.; Georgoulis, M. K.; Rust, D. M.; Bernasconi, P. N.

    With Flare Genesis Experiment (FGE), a balloon borne observatory launched in Antarctica on January 2000, series of high spatial resolution vector magnetograms, Dopplergrams, and Hα filtergrams have been obtained in an emerging active region (AR 8844). Previous analyses of this data revealed the occurence of many short-lived and small-scale Hα brightenings called 'Ellerman bombs' (EBs) within the AR. We performed an extrapolation of the field above the photosphere using the linear force-free field approximation. The analysis of the magnetic topology reveals a close connexion between the loci of EBs and the existence of ``Bald patches'' regions (BPs are regions where the vector magnetic field is tangential to the photosphere). Among 47 identified EBs, we found that 23 are co-spatial with a BP, while 19 are located at the footpoint of very flat separatrix field lines passing throught a distant BP. We reveal for the first time that some of these EBs/BPs are magneticaly connected by low-lying lines, presenting a 'sea-serpent' shape. This results leads us to conjecture that arch filament systems and active regions coronal loops do not result from the smooth emergence of large scale Ω loops, but rather from the rise of flat undulatory flux tubes which get released from their photospheric anchorage by reconnection at BPs, whose observational signature is Ellerman bombs.

  4. 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

  5. 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 μM) significantly increased BK-induced contractions (BK; 1 μM) 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 μM) 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 μg BPP-Cdc (69.7%), and this result was similar to that obtained with 50 μg 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 μg) 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

  6. 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

  7. 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

  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. 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

  10. 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

  11. 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

  12. In vitro neuromuscular activity of snake venoms.

    PubMed

    Hodgson, Wayne C; Wickramaratna, Janith C

    2002-09-01

    1. Snake venoms consist of a multitude of pharmacologically active components used for the capture of prey. Neurotoxins are particularly important in this regard, producing paralysis of skeletal muscles. These neurotoxins can be classified according to their site of action (i.e. pre- or post-synaptic). 2. Presynaptic neurotoxins, which display varying phospholipase A2 activities, have been identified in the venoms of the four major families of venomous snakes (i.e. Crotalidae, Elapidae, Hydrophiidae and Viperidae). The blockade of transmission produced by these toxins is usually characterized by a triphasic effect on acetylcholine release. Considerable work has been directed at identifying the binding site(s) on the presynaptic nerve terminal for these toxins, although their mechanism of action remains unclear. 3. Post-synaptic neurotoxins are antagonists of the nicotinic receptor on the skeletal muscle. Depending on their sequence, post-synaptic toxins are subdivided into short- and long-chain toxins. These toxins display different binding kinetics and different affinity for subtypes of nicotinic receptors. Post-synaptic neurotoxins have only been identified in venoms from the families Elapidae and Hydrophiidae. 4. Due to the high cost of developing new antivenoms and the reluctance of many companies to engage in this area of research, new methodologies are required to test the efficacy of existing antivenoms to ensure their optimal use. While chicken eggs have proven useful for the examination of haemorrhagic venoms, this procedure is not suited to venoms that primarily display neurotoxic activity. The chick biventer cervicis muscle has proven useful for this procedure, enabling the rapid screening of antivenoms against a range of venoms. 5. Historically, the lethality of snake venoms has been based on murine LD50 studies. Due to ethical reasons, these studies are being superseded by in vitro studies. Instead, the time taken to produce 90% inhibition of nerve-mediated twitches (i.e. t90) in skeletal muscle preparations can be determined. However, these two procedures result in different rank orders because they are measuring two different parameters. While murine LD50 determinations are based on "quantity", t90 values are based on how "quick" a venom acts. Therefore, knowledge of both parameters is still desirable. 6. In vitro neuromuscular preparations have proven to be invaluable tools in the examination of snake venoms and isolated neurotoxins. They will continue to play a role in further elucidating the mechanism of action of these highly potent toxins. Further study of these toxins may provide more highly specific research tools or lead compounds for pharmaceutical agents. PMID:12165047

  13. 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

  14. 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.

  15. 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)

  16. 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

  17. 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)

  18. 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:

  19. 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.

  20. A new species of Australotaenia (Cestoda: Proteocephalidea) from a snake in Cambodia: host switching or postcyclic parasitism in a distant region?

    PubMed

    de Chambrier, Alain; Scholz, Tomás

    2012-12-01

    Australotaenia de Chambrier et de Chambrier, 2010 has been proposed to accommodate two species of proteocephalidean cestodes from hylid frogs (Litoria spp.) in Australia. Recently, apparently congeneric cestode, for which the name A. bunthangi sp. n. is proposed, was found in the homalopsid snake Enhydris enhydris (Schneider) (Serpentes: Homalopsidae) from South-East Asia (Cambodia). This finding indicates a much wider range of definitive hosts of species of this genus, i.e. amphibians and reptiles, which is exceptional among proteocephalideans. Postcyclic parasitism, i.e. predation of the definitive host infected with sexually mature parasites, cannot be excluded but does not seem to be probable. In addition, the occurrence of A. bunthangi in the former Indochina extends the range of the geographical distribution of the genus to another zoogeographical region. The new species differs from both species of Australotaenia in the relative size of an apical organ, the diameter of which equals to that of suckers (versus much smaller in the remaining species, in which the width of the apical organ represents less than 2/3 of the diameter of the suckers), much smaller scolex and suckers (width 150 microm and diameter of suckers 50-55 microm versus 245-420 microm and 100-140 microm, respectively), and longer body (224 mm versus 57-121 mm). In addition, A. bunthangi differs from A. hylae (Johnston, 1912) (type-species of the genus) by the number of testes (46-64 versus 74-106 in A. hylae) and by the ovary width/proglottis width ratio (55-65% versus 68-71% in A. hylae). Australotaenia bunthangi differs from A. grobeli de Chambrier et de Chambrier, 2010 by relative size of the cirrus-sac (its length represents 18-24% of the width of the proglottis versus 27-33% in A. grobeli) and by the diameter of the embryophore (25-27 microm versus 18-23 microm in A. grobeli). PMID:23327009

  1. 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.

  2. 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.

  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. 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.

  5. 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.

  6. 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.

  7. 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)

  8. 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

  9. 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.

  10. 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

  11. 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

  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. 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

  15. [History of the treatment of varices].

    PubMed

    Janbon, C; Laborde, J C; Quere, I

    1994-01-01

    Diseases of the vein and particularly varicose veins have been recognized since antiquity. The Ebers papyrus, dated 1550 b.c., mentions serpent-shaped dilatation of the lower limbs. The Acropolis tablet of the IVth century b.c. concerning Dr Amynos allows us to visualize an enlarged lower limb clearly showing a varicosity. From 460-377 b.c., Hippocrates noted that a loose tourniquet leads to haemorrhages but that when the tourniquet is tight gangrene ensues and finally that standing up can exaggerate leg ulcerations. Of course much progress has been made since Hippocrates. The school at Alexandria, with Herophilus and Erasistrates speak of vascular ligatures. Their work was unfortunately lost in the fire of the Alexandria library in 391 a.d. Galien himself described varicose vein ligatures in 200 a.d. Leonardo de Vinci's magnificent anatomic studies of veins are widely known. In 1525, Ambroise Paré described leg bandaging for ulcers beginning from the foot up to the knee. In 1585, Fabrice d'Acquapendente described venous valves. In 1676, Wiseman invented the first supportive stockings made of leather and in 1854, Unna described in Vienna the supportive boot which now carries his name. Shortly thereafter new medical and surgical techniques were developed for the treatment of varicose veins. Pravaz, in 1860, invented a syringe which now carries his name and initiated sclerotherapy. At the end of the XIXth century, Trendelenburg performed the first ligatures of the greater saphenous veins. In 1905, and 1906, Keller and Mayo performed the first ablation of the greater saphenous vein and in 1906, Carrel reported the first venous transplantation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7798808

  16. 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: δ13C = -24.68‰ and δ15N = 14.22‰ and mean values of tissue and poisons snakes vivarium (Instituto Butantan) to carbon-13 and nitrogen-15 are δ13C = -20.47‰ and δ15N = 8.36‰, with a significantly different due to different sources of food animals. Based on all results isotopic δ13C and δ15N, 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  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. 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

  4. Clear New View of a Classic Spiral

    NASA Astrophysics Data System (ADS)

    2010-05-01

    ESO is releasing a beautiful image of the nearby galaxy Messier 83 taken by the HAWK-I instrument on ESO's Very Large Telescope (VLT) at the Paranal Observatory in Chile. The picture shows the galaxy in infrared light and demonstrates the impressive power of the camera to create one of the sharpest and most detailed pictures of Messier 83 ever taken from the ground. The galaxy Messier 83 (eso0825) is located about 15 million light-years away in the constellation of Hydra (the Sea Serpent). It spans over 40 000 light-years, only 40 percent the size of the Milky Way, but in many ways is quite similar to our home galaxy, both in its spiral shape and the presence of a bar of stars across its centre. Messier 83 is famous among astronomers for its many supernovae: vast explosions that end the lives of some stars. Over the last century, six supernovae have been observed in Messier 83 - a record number that is matched by only one other galaxy. Even without supernovae, Messier 83 is one of the brightest nearby galaxies, visible using just binoculars. Messier 83 has been observed in the infrared part of the spectrum using HAWK-I [1], a powerful camera on ESO's Very Large Telescope (VLT). When viewed in infrared light most of the obscuring dust that hides much of Messier 83 becomes transparent. The brightly lit gas around hot young stars in the spiral arms is also less prominent in infrared pictures. As a result much more of the structure of the galaxy and the vast hordes of its constituent stars can be seen. This clear view is important for astronomers looking for clusters of young stars, especially those hidden in dusty regions of the galaxy. Studying such star clusters was one of the main scientific goals of these observations [2]. When compared to earlier images, the acute vision of HAWK-I reveals far more stars within the galaxy. The combination of the huge mirror of the VLT, the large field of view and great sensitivity of the camera, and the superb observing conditions at ESO's Paranal Observatory makes HAWK-I one of the most powerful near-infrared imagers in the world. Astronomers are eagerly queuing up for the chance to use the camera, which began operation in 2007 (eso0736), and to get some of the best ground-based infrared images ever of the night sky. Notes [1] HAWK-I stands for High-Acuity Wide-field K-band Imager. More technical details about the camera can be found in an earlier press release (eso0736). [2] The data used to prepare this image were acquired by a team led by Mark Gieles (University of Cambridge) and Yuri Beletsky (ESO). Mischa Schirmer (University of Bonn) performed the challenging data processing. More information 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".

  5. 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.

  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. 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.)

  9. 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 Bursera tonkinensis and that its crown group radiation corresponds with the onset of the Miocene. Auffray (2007) in France studied the impact of two types of antioxidant on sebum squalene peroxidation by UV irradiation. The first type was free radical scavenger (Butyl hydroxyl toluene and an olive extract rich in hydroxytyrosol). The second type was the essential oil of C. myrrha, a singlet oxygen quencher. These properties were confirmed using the 2,2-diphenyl-1-picrylhydrazyl test for anti-radical capacity and 1,3-diphenylisobenzofuran test for the capacity to quench singlet oxygen. Also, the author extended an ex vivo method to classify the efficacy of cosmetics to protect squalene by collecting sebum in vivo and irradiating it in a controlled way. The squalene monohydroperoxide formation was monitored by high performance liquid chromatography. This method compared the efficiency of 3 antioxidants at 0.6% in a cosmetic formulation to protect squalene from photo oxidation. The data showed that essential oil of C. myrrha gave the best protection against squalene peroxidation, and that squalene peroxidation during solar exposure was mainly because of singlet oxygen and not due to free radical attack, and that sun care cosmetics should make use not only of free radical scavengers but also of singlet oxygen quenchers. This study aimed to review more than 70 out of hundreds papers (Pub-med-indexed for Medline) on the medical importance and safety of Commiphora molmol and other Commiphora species. PMID:19209761

  10. 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".

  11. 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.

  12. 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.