WorldWideScience

Sample records for argentinian bufonid toads

  1. Male size does not correlate with fertilization success in two bufonid toads that show size-assortative mating

    OpenAIRE

    Xiao-Li FAN, Zhi-Hua LIN, Xiang JI

    2013-01-01

    We examined sexual size dimorphism (SSD), mating pattern, fertilization efficiency and female reproductive traits in two bufonid toads (Bufo gargarizans and Duttaphrynus melanostictus) to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gargarizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficiencies on average...

  2. Male size does not correlate with fertilization success in two bufonid toads that show size-assortative mating

    Directory of Open Access Journals (Sweden)

    Xiao-Li FAN, Zhi-Hua LIN, Xiang JI

    2013-12-01

    Full Text Available We examined sexual size dimorphism (SSD, mating pattern, fertilization efficiency and female reproductive traits in two bufonid toads (Bufo gargarizans and Duttaphrynus melanostictus to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gargarizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficiencies on average were higher in B. gargarizans (95% than in D. melanostictus (91%. Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects: (1 both showed size-assortative mating; (2 females did not tradeoff egg size against egg number; (3 male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length (SVL; and (4 the ratio of male to female SVL did not affect fertilization efficiency. Our data show that: (1 a female preference for large males is likely not important in terms of egg fertilization success; (2 a male preference for large females is likely important because larger females are more fecund; and (3 size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating [Current Zoology 59 (6: 740–746, 2013].

  3. Niche overlap and resource partitioning among five sympatric bufonids (Anura, Bufonidae from northeastern Argentina

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    Marta I. Duré

    2009-07-01

    Full Text Available The niche overlap and resource partitioning were analyzed for five sympatric bufonids from Northeastern Argentina: Rhinella schneideri, R. bergi, R. fernandezae, R. granulosa, and Melanophryniscus cupreuscapularis. The primary objectives were to analyze the diet and pattern of coexistence relative to the microhabitats among species. The bufonids, which are primarily terrestrial, exhibited a preference for small, hard prey such as formicids or coleopterans. The smallest species preferably consumed ants, while R. schneideri preferred beetles. Significant differences were detected for the diets of these five species. In addition, significant overlap in the trophic niche was noted for all species except between R. granulosa and R. schneideri. Studying the diet behaviors and trophic parameters of sympatric species provides important data for understandingthe community and for the development of conservation guidelines.

  4. Recent fluctuations of the Argentinian glaciers

    Science.gov (United States)

    Leiva, Juan Carlos

    1999-10-01

    Some of the results obtained in the glaciological research carried out since 1979 at the Argentinian Andes are shown in this paper. The research covers a wide latitudinal gap extending from the Agua Negra glacier in the province of San Juan to the Frı´as glacier situated at Mount Tronador. Agua Negra and Piloto glaciers show a very similar behavior of almost continuous retreat since 1965 while at the Plomo region a small advance period, starting in 1982, is observed in five of the 10 glaciers studied. Finally, the Frı´as glacier fluctuations record shows a very strong recession since 1850 only interrupted by the 1976 advance that continued in 1977.

  5. First occurrence of tetrodotoxin in a dendrobatid frog (Colostethus inguinalis), with further reports for the bufonid genus Atelopus.

    Science.gov (United States)

    Daly, J W; Gusovsky, F; Myers, C W; Yotsu-Yamashita, M; Yasumoto, T

    1994-03-01

    The water-soluble toxin present in skin of Colostethus inguinalis (Dendrobatidae) was identified as tetrodotoxin by fluorometric HPLC analysis. The amount of tetrodotoxin per frog skin was estimated by HPLC, mouse toxicity, and inhibition of [3H]saxitoxin binding to brain membranes as 0.1 to 1.2 micrograms. Small amounts of anhydrotetrodotoxin and 4-epietrodotoxin also were present. Tetrodotoxin-like activity was not detected by inhibition of [3H]saxitoxin binding in other species of Colostethus nor in other dendrobatids (Aromobates, Dendrobates, Phyllobates). Tetrodotoxin-like activity was present in extracts of skin of five species of Atelopus (Bufonidae). HPLC analysis identified tetrodotoxin as the major toxic component in Atelopus spumarius and A. varius, as a minor component in A. spurrelli, and as a trace component in A. ignescens and A. zeteki. The major tetrodotoxin-like compounds in the last three species were not identified. Tetrodotoxin-like activity was not detected by inhibition of [3H]saxitoxin binding in skin extracts from three other genera of bufonids. PMID:8016850

  6. Diseases of frogs and toads

    Science.gov (United States)

    Green, D.E.; Converse, K.A.; Majumdar, S.K.; Huffman, J.E.; Brenner, F.J.; Panah, A.I.

    2005-01-01

    This chapter presents information on infectious diseases of free-living frogs and toads that have completed metamorphosis. The diseases discussed in this chapter pertain principally to sub-adult and adult frogs and toads that are at least 60-90 days removed from completion of metamorphosis. The main emphasis of this chapter is the diseases found in amphibians of Canada and the United States. Diseases of recent metamorphs, larvae and amphibian eggs are presented in the chapters Diseases of Amphibian Eggs and Embryos and Diseases of Tadpoles. The smallest disease agents (viruses and bacteria) are presented first, followed by fungi, protozoa, helminths and ectoparasites. Diseases presented in this chapter are Ranaviral (iridovirus) infection Lucke frog herpesvirus (kidney cancer) Frog erythrocytic virus West Nile virus Red-leg disease (bacterial septicemia) Salmonellosis Chytrid fungal infection Basidiobolus fungi Dermosporidiosis Ichthyophoniasis Dermocystidium & Dermomycoides Myxozoa Ribeiroia flukes and Amphibian malformations Clinostomum metacercaria Aspects of each disease are presented to assist the biologist with recognition of diseases in the field. Hence, the major emphases for identification of diseases are the epizootiological aspects (host species, life stage, casualty numbers, etc) and gross findings ('lesions'). Descriptions of the microscopical, ultrastructural and cultural characteristics of each infectious agent were considered beyond the scope of this text. Detailed cultural and microscopical features of these disease agents are available in other reviews (Taylor et al., 2001; Green, 2001). Some diseases, while common in captive and zoo amphibians, are exceptionally rare in free-living frogs and toads, and therefore are omitted from this review. Among the diseases not presented are infections by chlamydia and mycobacteria, which occur principally in captive colonies of African clawed frogs (Xenopus, Hymenochirus, et al.) and northern leopard frogs

  7. critical habitat designated for the arroyo toad

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas (in general) of critical habitat designated for the arroyo toad. NOTE: THIS DATA SET INCLUDES APPROXIMATELY 900 ACRES OF LAND...

  8. INFLUENCE OF GM SOY EXPANSION ON THE ARGENTINIAN FOOD AND NUTRITION SECURITY

    OpenAIRE

    Zanasi, Cesare; Rota, Cosimo; Severi, Claudia; Demadonna, Anna

    2015-01-01

    The rapid expansion of Argentinian soy production, led by the increase in the international soy demand for food feed and biofuel production, deeply influenced the entire Argentinian society economy and environment. Genetically modified soy has become a strategic product for the Latin American country, strongly supporting the entire economy and the welfare state thanks to the income derived from soy production and export taxations. The influence of the GM soy production strongly modified in pa...

  9. Toad envenoming in dogs: effects and treatment

    OpenAIRE

    M. SAKATE; P. C. Lucas de Oliveira

    2000-01-01

    Toads (order: Anura; family: Bufonidae; genus: Bufo) are distributed throughout the world, but more species are found in areas of tropical and humid temperate climates. Although toads do not have a venom inoculation system, they are venomous animals because the glands covering the whole surface of their bodies secrete a milk-like venom of which composition is not yet completely known. Some of these glands are the bilateral glands located in post-orbital position. These glands, which are somew...

  10. A review of the geology of the Argentinian Fuegian Andes

    Science.gov (United States)

    Olivero, Eduardo B.; Martinioni, Daniel R.

    2001-06-01

    Seven stratigraphic units reflect the tectonic evolution of the Argentinian Fuegian Andes: Basement (Paleozoic-Jurassic); Lemaire Formation (Upper Jurassic); Yahgan-Beauvoir formations (Lower Cretaceous); Cerro Matrero Formation (Upper Cretaceous); Rı´o Claro Formation (Paleocene); La Despedida Group (Eocene); and Cabo Peña Formation (uppermost Eocene-Lower Oligocene). Basement rocks (garnet, quartz-sericite, and chlorite schists; and amphibolites) are unconformably covered by the Lemaire Formation (rhyolites; basalts; slates; and acidic volcaniclastic breccias, tuffs, conglomerates, and turbidites), formed during extensional tectonism. The post-rift Yahgan Formation (deep-marine black mudstones, andesitic volcaniclastic turbidites and tuffs) interfingers northward with the Beauvoir Formation (slope and platform black mudstones), and covers the Lemaire Formation unconformably. The Yahgan Formation represents an andesitic, volcaniclastic apron, coeval with a Pacific volcanic-arc, filling a marginal basin floored with oceanic crust. The Late Cretaceous compressional orogeny resulted in tectonic inversion, closure of the marginal basin, peak metamorphism and folding, and initial uplifting of the Fuegian Andes. By the latest Cretaceous-earliest Paleogene, the Andes were exposed to subaerial erosion, and the lowest Danian Rı´o Claro Formation bears clear evidence of an Andean clastic provenance. The Rı´o Claro Formation represents the first molasse deposits of the foreland stage of evolution of the Fuegian Andes. Earliest Paleogene north-verging thrust propagation deformed the Rı´o Claro Formation and older units, producing northward depocenter migration. La Despedida Group rests unconformably on the Rı´o Claro Formation and is involved in the thrust and fold belt. Important Eocene compression resulted in thrusting of central Andean basement schists and the Lemaire Formation over Lower Cretaceous and continental Paleogene rocks, respectively. In the

  11. Sulfate transport in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Simonsen, K

    1988-01-01

    -circuited preparations resulted in a significant stimulation of the passive Cl- and SO2(-4) permeabilities. 6. It is suggested that SO2(-4) and Cl- ions are transported along the same pathway of the m.r. cells. Depending on the transport mode of the apical Cl- transport system, electro-diffusion, active transport......1. In short-circuited toad skin preparations exposed bilaterally to NaCl-Ringer's containing 1 mM SO2(-4), influx of sulfate was larger than efflux showing that the skin is capable of transporting sulfate actively in an inward direction. 2. This active transport was not abolished by substituting...... apical Na+ for K+. 3. Following voltage activation of the passive Cl- permeability of the mitochondria-rich (m.r.) cells sulfate flux-ratio increased to a value predicted from the Ussing flux-ratio equation for a monovalent anion. 4. In such skins, which were shown to exhibit vanishingly small leakage...

  12. Genetic polymorphism of milk protein loci in Argentinian Holstein cattle

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    Bonvillani Adriana Gloria

    2000-01-01

    Full Text Available Some alleles of milk protein loci are associated with superior cheese production characteristics. The genetic polymorphism of the milk protein loci alphas1-casein, beta-casein, k-casein and beta-lactoglobulin was examined in Argentinian Holstein cattle. Samples from 12 herds of four regions of Córdoba were analyzed by starch gel electrophoresis. The chi² test was used to assess whether the populations were in Hardy-Weinberg equilibrium. Genotypic diversity was analyzed by the Shannon-Weaver index. The observed genotypic frequencies were analyzed by Hedrick's genetic identity and the genetic distance of Balakrishnan and Sanghvi. The allelic and genotypic frequencies were similar to those of other Holstein populations. The genotypic frequencies of the alphas1-casein and beta-casein loci were in equilibrium, whereas in some populations the k-casein and beta-lactoglobulin loci were not. According to the Shannon-Weaver index the total genetic diversity within each herd was greater than 96%. The high values of identity agreed with the low genetic distances among populations. We conclude that there is extensive genetic homogeneity in Holstein cattle in Córdoba Province and that it would be feasible to select for B alleles at the k-casein and b-lactoglobulin loci in order to improve the quality of milk available for cheese manufacturing.

  13. The Construction of National Memory Through Popular Culture. The Case of the Argentinian TV Show,

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    Elizondo Oviedo, María Verónica

    2010-07-01

    Full Text Available This article addresses the borders of the complex television sign through the analysis of the Argentinian TV show "Peter Capusotto y sus videos". In it we find that humor is used as a mechanism to dismantle binary hierarchic political and social oppositions. The program is presented as a musical and comedy TV show where concepts such as popular culture and mass culture are questioned through different false musicians. We focus our attention in the character of Bombita Rodríguez, el Palito Ortega montonero due to the controversy generated in the cultural scene by the fact of bringing up recent aspects of Argentinian history.

  14. Toads on Lava: Spatial Ecology and Habitat Use of Invasive Cane Toads (Rhinella marina) in Hawai’i

    OpenAIRE

    Georgia Ward-Fear; Greenlees, Matthew J.; Richard Shine

    2016-01-01

    Most ecological research on cane toads (Rhinella marina) has focused on invasive populations in Australia, ignoring other areas where toads have been introduced. We radio-tracked and spool-tracked 40 toads, from four populations on the island of Hawai'i. Toads moved extensively at night (mean 116 m, from spool-tracking) but returned to the same or a nearby retreat-site each day (from radio-tracking, mean distance between successive retreat sites 11 m; 0 m for 70% of records). Males followed s...

  15. Estimation of temporary emigration in male toads

    Science.gov (United States)

    Muths, E.; Scherer, R. D.; Corn, P.S.; Lambert, B.A.

    2006-01-01

    Male boreal toads (Bufo boreas) are thought to return to the breeding site every year but, if absent in a particular year, will be more likely to return the following year. Using Pollock's robust design we estimated temporary emigration (the probability a male toad is absent from a breeding site in a given year) at three locations in Colorado, USA: two in Rocky Mountain National Park and one in Chaffee County. We present data that suggest that not all male toads return to the breeding site every year. Our analyses indicate that temporary emigration varies by site and time (for example, from 1992 to 1998, the probability of temporary emigration ranged from 10% to 29% and from 3% to 95% at Lost Lake and Kettle Tarn, respectively). Although the results provide weak evidence that males are more likely to return after a year's hiatus, a general pattern of state-dependent temporary emigration was not supported. We also hypothesized relationships between temporary emigration and a number of weather variables. While some competitive models included weather covariates, imprecise and variable estimates of the effects of these covariates precluded fully defining their impact on temporary emigration. ?? 2006 by the Ecological Society of America.

  16. Kinematics of Chinese toad Bufo gargarizans

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A three-dimensional motion force tester for animal was used to measure the reaction forces of the feet of a Chinese toad (B. gargarizans) against a horizontal solid surface on which it crawled. The motion behavior of the Chinese toad was recorded by a high-speed camera on line. The motor function of every foot was analyzed. It was found that the lateral force represents the control ability of side-to-side locomotion, controls the lateral movement, and maintains a stable state for the sustainable creeping gesture. The forefeet play the assistant role and the hind feet play the main role in driving. The normal force of the forefeet is significantly greater than that of the hind feet, so the forefeet play the main role in supporting the body and the hind feet play the assistant role. The normal force is significantly greater than the lateral force and the driving force as well. There is little change for the friction force and the support angle of the all four feet. The average value of the support angle is 70°–80°. The Chinese toad’s vola friction coefficient of the forefeet is less than that of the hind feet. The above results indicate that the difference in kinematics and the material characteristic of the contact skin of the Chinese toad. The results could be useful to the structure design and gait optimization of some robots.

  17. Toads on Lava: Spatial Ecology and Habitat Use of Invasive Cane Toads (Rhinella marina in Hawai'i.

    Directory of Open Access Journals (Sweden)

    Georgia Ward-Fear

    Full Text Available Most ecological research on cane toads (Rhinella marina has focused on invasive populations in Australia, ignoring other areas where toads have been introduced. We radio-tracked and spool-tracked 40 toads, from four populations on the island of Hawai'i. Toads moved extensively at night (mean 116 m, from spool-tracking but returned to the same or a nearby retreat-site each day (from radio-tracking, mean distance between successive retreat sites 11 m; 0 m for 70% of records. Males followed straighter paths during nocturnal movements than did females. Because moist sites are scarce on the highly porous lava substrate, Hawai'ian toads depend on anthropogenic disturbance for shelter (e.g. beneath buildings, foraging (e.g. suburban lawns, golf courses and breeding (artificial ponds. Foraging sites are further concentrated by a scarcity of flying insects (negating artificial lights as prey-attractors. Habitat use of toads shifted with time (at night, toads selected areas with less bare ground, canopy, understory and leaf-litter, and differed between sexes (females foraged in areas of bare ground with dense understory vegetation. Cane toads in Hawai'i thrive in scattered moist patches within a severely arid matrix, despite a scarcity of flying insects, testifying to the species' ability to exploit anthropogenic disturbance.

  18. Toads on Lava: Spatial Ecology and Habitat Use of Invasive Cane Toads (Rhinella marina) in Hawai'i.

    Science.gov (United States)

    Ward-Fear, Georgia; Greenlees, Matthew J; Shine, Richard

    2016-01-01

    Most ecological research on cane toads (Rhinella marina) has focused on invasive populations in Australia, ignoring other areas where toads have been introduced. We radio-tracked and spool-tracked 40 toads, from four populations on the island of Hawai'i. Toads moved extensively at night (mean 116 m, from spool-tracking) but returned to the same or a nearby retreat-site each day (from radio-tracking, mean distance between successive retreat sites 11 m; 0 m for 70% of records). Males followed straighter paths during nocturnal movements than did females. Because moist sites are scarce on the highly porous lava substrate, Hawai'ian toads depend on anthropogenic disturbance for shelter (e.g. beneath buildings), foraging (e.g. suburban lawns, golf courses) and breeding (artificial ponds). Foraging sites are further concentrated by a scarcity of flying insects (negating artificial lights as prey-attractors). Habitat use of toads shifted with time (at night, toads selected areas with less bare ground, canopy, understory and leaf-litter), and differed between sexes (females foraged in areas of bare ground with dense understory vegetation). Cane toads in Hawai'i thrive in scattered moist patches within a severely arid matrix, despite a scarcity of flying insects, testifying to the species' ability to exploit anthropogenic disturbance. PMID:27027738

  19. The late Oligocene flora from the Río Leona Formation, Argentinian Patagonia

    OpenAIRE

    Césari, Silvia N.; Panti, Carolina; Roberto R Pujana; Francis, Jane E.; Sergio A Marenssi

    2015-01-01

    A late Oligocene plant macrofossil assemblage is described from the Río Leona Formation, Argentinian Patagonia. This includes a fern, “Blechnum turbioensis” Frenguelli, one species of conifer, and sixteen angiosperm taxa. Rosaceae, Myrtaceae, Proteaceae, Lauraceae, Anacardiaceae and Typhaceae are represented by one species in each family. Five species are considered to be members of the Fabales. Three leaf taxa together with Carpolithus seeds are placed in the Nothofagaceae. Palynomorphs and ...

  20. Biogeographic patterns of Colombian frogs and toads

    International Nuclear Information System (INIS)

    Using the data provided in Ruiz-Carranza et al. (1996) the distributions of the 540 species of frogs and toads are partitioned among ten ecogeographic units of Colombia defined on the basis of precipitation and elevation. Some lowlands areas (pacific lowlands, Amazonian) exhibit high diversity (85-94 species) but lowlands areas in general are impoverished (30-52 species), especially when contrasted with upland areas. The three Andean cordilleras harbor between 87 and 121 species of frogs and toads, demonstrating that the biodiversity of Colombia resides primarily in its montane components, not in its lowland rain forests. When biological endemicity is separated from political endemicity, five areas of high endemicity remain (the three Andean cordilleras, the Sierra Nevada de Santa Marta, and the pacific lowlands). We endeavor to explain this description by recourse to cladistic analyses of several groups of leptodactylid frogs where we find that the general pattern of diversification is by means of horizontal diversification (allopatric speciation) with a minor contribution from vertical diversification

  1. Thyroid anatomy and topography of toad (Bufo marinus ictericus)

    International Nuclear Information System (INIS)

    The autoradiographic method is used for the study of the toad's thyroid of Bufo marinus ictericus by 131I. Histolological proceedings are done. Comparative evaluations with bibliographic informations are presented. (M.A.C.)

  2. Final Critical Habitat for the Houston toad (Bufo houstonensis)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Houston toad (Bufo houstonensis) based on the description provided in the Federal...

  3. Conservation genetics of an island toad: Bufo bufo in Jersey

    OpenAIRE

    John W. Wilkinson; Trevor J C Beebee; Griffiths, Richard A.

    2007-01-01

    On Jersey (British Channel Islands), common toads often reproduce in small, urban ponds. This atypical breeding strategy has implications for their persistence and they have declined on the island in recent times. We used polymorphic microsatellite markers to compare genetic diversity in Bufo bufo from five different ponds in Jersey with two populations from north-west France. Genetic diversity of Jersey toads was comparable with that of populations elsewhere in Europe. Numbers of breeding fe...

  4. The 'Prof. Dr. Rómulo Lambre' Collection: an Argentinian sample of modern skeletons.

    Science.gov (United States)

    Salceda, S A; Desántolo, B; Mancuso, R García; Plischuk, M; Inda, A M

    2012-08-01

    This paper describes the 'Prof. Dr. Rómulo Lambre' skeletal collection. The Lambre Collection is housed in the School of Medical Sciences of the National University of La Plata and it consists of skeletal remains ceded by the Municipal Cemetery of La Plata. The collection has more than four hundred skeletons, with information on age, sex, nationality, date and cause of death. It was created for teaching and research purposes in compliance with current legislation, and its management meets guidelines specified in the Declaration of the Argentinian Association for Biological Anthropology on Research Ethics on Human Remains (2007). PMID:22769855

  5. Diet composition of the invasive cane toad (Chaunus marinus) on Rota, Northern Mariana Islands

    Science.gov (United States)

    Reed, R.N.; Bakkegard, K.A.; Desy, G.E.; Plentovich, S.M.

    2007-01-01

    The cane or marine toad (Chaunus marinus, formerly Bufo marinus) was introduced to the Northern Mariana Islands starting in the 1930s. The effects of this exotic predator on native vertebrates (especially lizards) are largely unknown. We analysed the stomach contents of 336 cane toads collected from the island of Rota, with the goal of estimating the level of toad predation on native vertebrates. Beetles, ants, millipedes, and grasshoppers/crickets comprised the majority of prey classes consumed by toads. The introduced Brahminy blindsnake (Ramphotyphlops braminus; N = 6) and conspecific cane toads (N = 4) were the vertebrates most commonly found in toad stomachs. Skinks (Emoia; N = 2) were the only native vertebrates represented in our sample. The small numbers of nocturnal terrestrial vertebrates native to Rota likely translates to relatively low rates of predation by cane toads on native vertebrates.

  6. Study of the characteristic parameters of the normal voices of Argentinian speakers

    Directory of Open Access Journals (Sweden)

    Edgardo Bonzi

    2014-02-01

    Full Text Available The voice laboratory permits to study the human voices using a method that is objective and noninvasive. In this work, we have studied the parameters of the human voice such as pitch, formant, jitter, shimmer and harmonic-noise ratio of a group of young people. This statistical information of parameters is obtained from Argentinian speakers. Received: 29 December 2013, Accepted: 27 May 2014; Reviewed by: J. Brum, Instituto de Física, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Edited by: E. Mizraji; DOI: http://dx.doi.org/10.4279/PIP.060002 Cite as: E V Bonzi, G B Grad, A M Maggi, M R Muñoz, Papers in Physics 6, 060002 (2014

  7. Evaluation of Argentinian industrial capacity and of suppliers for nuclear installations

    International Nuclear Information System (INIS)

    This work describes and analyses the Argentinian system of purchasing, the laws and decrees which must be observed by the State enterprises and dependent bodies such as the National Atomic Energy Commission (C.N.E.A.). Within the system there are regulations which must be observed by the State suppliers, and to which the purchasing bodies must conform. Furthermore, there is a thorough analysis of the methods implemented before beginning the construction of the third nuclear plant in Argentina, the Atucha II Nuclear Plant. For this, all the existing antecedents were taken into account, insofar as they were related to the prior projects, and an exhaustive questionnaire was elaborated, in which the examined enterprises described in detail their installed capacity, their antecedents, their human resources, etc. The data thus obtained were evaluated and the task was concluded by drawing up lists of the possible enterprises to supply the most diverse components, services or equipment required both by the electrical plant and for any other large scale work. The evaluation obtained would allow an analysis of the foreign offers concerning the entire project and of the possible participation with each bidder of Argentinian industry and engineering. A description is given of the advanced method used to assess bidders with respect to such participation, to assess the replies to the questionnaire, which were analysed in detail, and the weighting factors applied to each item. Also described are some major contracts concluded with enterprises in the country. These contracts relate to the external acquisition of technology for nuclear plants and the essential points are outlined. Also analysed are the results obtained during the execution of the programmes of technology transfer and training, both for parts of different enterprises selected to produce the components, and for the State, through C.N.E.A. and ENACE S.A. 6 refs, 5 tabs

  8. DIET OF THE SOUTHERN TOAD FROM THE SOUTHERN EVERGLADES

    Science.gov (United States)

    We examined the diet of a February-May sample of the southern toad (Bufo Terrestris) from the Everglades National Park. Above the familial level, 13 taxa were consumed, but ants (Hymenoptera) and beetles (Coleoptera) were consumed most by, and in the greatest number of s...

  9. Determinants of Instrumental Extinction in Terrestrial Toads ("Bufo arenarum")

    Science.gov (United States)

    Muzio, Ruben N.; Ruetti, Eliana; Papini, Mauricio R.

    2006-01-01

    Previous research in a water-reinforced instrumental training situation with toads ("Bufo arenarum") has shown that performance in both acquisition and extinction is poorer after partial, rather than continuous reinforcement training. In Experiment 1, the performance of a group receiving 24 trials on a 50% partial reinforcement schedule was poorer…

  10. Behavior of toads, Bufo bufo, in a dynamic environment.

    Science.gov (United States)

    Lychakov, D V

    2009-01-01

    Susceptibility to motion sickness was tested by exposing free moving toads to rotation of a stimulator modeled after an amusement park Ferris Wheel. The stimulator provided a gentle stimulation of frequency 0.25 Hz and centrifugal acceleration 0.143 g during 120 min or more without external visual cues. No emetic or prodromal behavioral response was elicited during or after rotation. During rotation the amount of motor activity in most toads increased evidently. The most active toads attempted to climb out of the test chamber. It was inferred that experimental rotation was rather a stressful stimulus which initiated an escape response. In addition, during rotation the number of eye retractions and urination incidences increased, but appetite after rotation was inhibited. During rotation the motionless toads performed small regular head movements with period equal to rotation period of stimulator. These oscillations were probably vestibular (otolith) reaction to oscillating acceleration. The proposed resonance hypothesis gives a general idea of why lower vertebrates are immune to motion sickness.

  11. Shifts in life history as a response to predation in western toads (Bufo boreas)

    OpenAIRE

    Chivers, Douglas P.; Marco, Adolfo; Kiesecker, Joseph M.; Wildy, Erica L.; Andrew R. Blaustein

    1999-01-01

    Larval western toads (Bufo boreas) are known to exhibit antipreda­ tor behavior in response to both chemical alarm cues released from injured conspecifics and chemical cues of predatory invertebrates. In this study, we tested whether long-term exposure to predator and alarm cues resulted in an adaptive shift in life history characteristics of the toads. We raised groups of tadpoles in the presence of: (1) predatory backswimmers (Notonecta spp.) that were fed toad tadpoles, (2) nonpredatory w...

  12. The induction of neoplastic lesions by aflatoxin-B1 in the Egyptian toad (Bufo regularis).

    Science.gov (United States)

    el-Mofty, M M; Sakr, S A

    1988-01-01

    The carcinogenic activity of aflatoxin-B1, the metabolic product of the mold Aspergillus flavus (a commonly occurring contaminant of groundnuts and other foodstuffs), was tested using the Egyptian toad (Bufo regularis). Injecting the toads with aflatoxin-B1 at a dose level of 0.01 mg/50 g body wt in 1 ml corn oil once a week for 15 weeks induced hepatocellular carcinomas in 19% of the experimental toads. Four toads developed tumors in the kidney due to metastases from the primary hepatocellular carcinomas.

  13. Travelling waves for the cane toads equation with bounded traits

    International Nuclear Information System (INIS)

    In this paper, we study propagation in a non-local reaction–diffusion–mutation model describing the invasion of cane toads in Australia (Phillips et al 2006 Nature 439 803). The population of toads is structured by a space variable and a phenotypical trait and the space diffusivity depends on the trait. We use a Schauder topological degree argument for the construction of some travelling wave solutions of the model. The speed c* of the wave is obtained after solving a suitable spectral problem in the trait variable. An eigenvector arising from this eigenvalue problem gives the flavour of the profile at the edge of the front. The major difficulty is to obtain uniform L∞ bounds despite the combination of non-local terms and a heterogeneous diffusivity. (paper)

  14. Travelling waves for the cane toads equation with bounded traits

    Science.gov (United States)

    Bouin, Emeric; Calvez, Vincent

    2014-09-01

    In this paper, we study propagation in a non-local reaction-diffusion-mutation model describing the invasion of cane toads in Australia (Phillips et al 2006 Nature 439 803). The population of toads is structured by a space variable and a phenotypical trait and the space diffusivity depends on the trait. We use a Schauder topological degree argument for the construction of some travelling wave solutions of the model. The speed c* of the wave is obtained after solving a suitable spectral problem in the trait variable. An eigenvector arising from this eigenvalue problem gives the flavour of the profile at the edge of the front. The major difficulty is to obtain uniform L∞ bounds despite the combination of non-local terms and a heterogeneous diffusivity.

  15. Isoflurane, sevoflurane and desflurane use in cane toads (Rhinella marina).

    Science.gov (United States)

    Morrison, Kaleigh E; Strahl-Heldreth, Danielle; Clark-Price, Stuart C

    2016-01-01

    Anaesthetic chamber concentrations of isoflurane, sevoflurane and desflurane that resulted in loss of righting reflex within 15 minutes in 50 per cent of toads (Rhinella marina) exposed (ED50-LRR<15MIN) were identified. The median and range ED50-LRR<15MIN was 1.4 (0.9-1.4) per cent for isoflurane, 1.75 (1.1-1.9) per cent for sevoflurane and 4.4 (4.3-5.5) per cent for desflurane. Subsequently, toads were exposed to 1.5 times the ED50-LRR<15MIN and times to loss and return of righting reflex were identified. All toads for all anaesthetics lost righting reflex. The median and range loss of righting reflex was 4:00 (3:00-5:30) minutes for isoflurane, 4:45 (3:30-7:00) minutes for sevoflurane, and 4:15 (4:00-5:30) minutes for desflurane and was not different between anaesthetics. Time to return of righting reflex was 175 (123-211) minutes for isoflurane, 192 (116-383) minutes for sevoflurane and 74 (52-220) minutes for desflurane. Time to return of righting reflex was significantly shorter for desflurane compared with isoflurane or sevoflurane. The use of isoflurane, sevoflurane or desflurane can be used to provide immobilisation to cane toads and potentially other anurans. Induction times are likely similar when using an anaesthetic chamber to provide anaesthesia. However recovery time may take twice as long when utilising isoflurane or sevoflurane over desflurane. PMID:27651914

  16. Habitat use and movement of the endangered Arroyo Toad (Anaxyrus californicus) in coastal southern California

    Science.gov (United States)

    Gallegos, Elizabeth; Lyren, Lisa M.; Lovich, Robert E.; Mitrovich, Milan J.; Fisher, Robert N.

    2011-01-01

    Information on the habitat use and movement patterns of Arroyo Toads (Anaxyrus californicus) is limited. The temporal and spatial characteristics of terrestrial habitat use, especially as it relates to upland use in coastal areas of the species' range, are poorly understood. We present analyses of radiotelemetry data from 40 individual adult toads tracked at a single site in coastal southern California from March through November of 2004. We quantify adult Arroyo Toad habitat use and movements and interpret results in the context of their life history. We show concentrated activity by both male and female toads along stream terraces during and after breeding, and, although our fall sample size is low, the continued presence of adult toads in the floodplain through the late fall. Adult toads used open sandy flats with sparse vegetation. Home-range size and movement frequency varied as a function of body mass. Observed spatial patterns of movement and habitat use both during and outside of the breeding period as well as available climatological data suggest that overwintering of toads in floodplain habitats of near-coastal areas of southern California may be more common than previously considered. If adult toads are not migrating out of the floodplain at the close of the breeding season but instead overwinter on stream terraces in near-coastal areas, then current management practices that assume toad absence from floodplain habitats may be leaving adult toads over-wintering on stream terraces vulnerable to human disturbance during a time of year when Arroyo Toad mortality is potentially highest.

  17. Diazinon mediated biochemical changes in the African toad (Bufo regularis

    Directory of Open Access Journals (Sweden)

    Isioma Tongo

    2012-07-01

    Full Text Available The sublethal toxicity of diazinon to the adult African toad, Bufo regularis was assessed using an integration of biomarkers. Changes in acetylcholinesterase (AChE, corticosterone and total protein levels were assessed in the serum, brain, liver, lungs and gastrointestinal tract (GIT and the results supported by bioaccumulation data. The biomarkers were chosen as indicators of key physiological functions: AChE for neurotoxicity, corticosterone and total protein levels as indicators of oxidative stress. Toads were exposed to 0.01, 0.02, 0.03 and 0.04 g/L for 28 days. Brain AChE activity reduced by 96% in the highest concentration (0.04 g/L compared to the control brain. Similarly, AChE activities in serum, liver, lungs and GIT tissues (88%, 88%, 87, 87% umg-1 protein respectively were also inhibited in the toads. Corticosterone and total protein levels in the tissues decreased compared to the control. The accumulation results obtained showed accumulation in the tissues (liver>serum>brain> lung>GIT, with a direct relationship between tissue concentration and changes in the biochemical indices. The alterations in all the indices were significantly concentration dependent. The biomarkers described in this study could be useful complementary indices in the risk assessment of diazinon pesticide.

  18. Insights into ecological and reproductive aspects of two cryptogenic peracarid crustaceans of the Argentinian coast

    Directory of Open Access Journals (Sweden)

    Anna Fricke

    2015-09-01

    Full Text Available AbstractPeracarid crustaceans belong to the most important agglomerating macrofauna in sedimentary habitats. The amphipod Monocorophium insidiosumCRAWFORD, 1937 and the tanaid Tanais dulongii AUDOUIN, 1926 are listed as invasive species. In the present study, we investigated the ecology of M. insidiosum and T. aff. dulongii from the Argentinian coast. Both crustaceans were breeding under laboratory conditions to study their fecundity and growth. Additionally their behavior and potential interspecific relations have been investigated in four different laboratory experiments. We evaluated tube building capabilities (experiment 1, and tested gender specific responses of M. insdiosum to the presence of empty (experiments 2 and 3, and inhabited T. aff. dulongii tubes (experiment 4. Our results showed high fecundity (three generations within four weeks and growth rates (duplication of body lengths in two weeks for M. insidiosum. Two tube construction strategies were distinguished: a tube changing behavior for the amphipod M. insidiosum, showing greater construction activity for females, and tube keeping behavior for T. aff. dulongii. Overall, tanaid tubes were frequently claimed by M. insidiosum, demonstrating a close interspecific relationship and resulting in decreased sediment aggregating activity. In the light of our observations it may be affirmed that these invasive species are probably frequently distributed along the Patagonian Atlantic coast and will still spread in future.

  19. Soil physical quality changes under different management systems after 10 years in Argentinian Humid Pampa

    Science.gov (United States)

    Costa, J. L.; Aparicio, V. C.; Cerda, A.

    2014-08-01

    The Argentinian Humid Pampa extends over about 60 million ha, 90% of which are agricultural lands. The southeast of the Buenos Aires Province is part of the Humid Pampa (1 206 162 ha). The main crops are wheat, sunflower, corn and soybean. The management systems used in the area are: moldboard plow (MP), chisel plow (CP) and no-till (NT). Excessive soil cultivation under MP causes decreases in the soil organic carbon content (SOC). Adopting NT may reduce the effects of intensive agriculture, through the maintenance and accumulation of SOC. However, the soil compaction under NT causes degradation of the soil structure, reduces the soil water availability and reduces the soil hydraulic conductivity. We evaluated the evolution of the soil physical parameters in three management systems. After 10 years of experiments in four farmers' fields, we found that: soil bulk density was significantly higher under NT. The change in mean weight diameter (CMWD) of aggregates increased as the management system became more intensive. We did not find significant differences in time and management systems in hydraulic conductivity at tension (h)0 cm and h=20 cm. The reduction in total porosity under NT is mainly a product of a reduction in the percentage of mesopores in the soil. Time had no statistically significant effect on the SOC content. The management system did not affect the yields of crop. In this work, the results indicate a modification of some soil physical parameters (porosity, near-saturated hydraulic conductivity, soil structure) due to uninterrupted agricultural production.

  20. The accreditation process of careers in MERCOSUR: would the veterinary career in Uruguay achieve accreditation in accordance with the required standards of the Argentinian and Brazilian agencies?

    Directory of Open Access Journals (Sweden)

    José Passarini

    2015-06-01

    Full Text Available MERCOSUR created the ARCU-SUR system as a regional mechanism for accreditation of undergraduate programmes. The Veterinary career in Uruguay achieved accreditation by ARCU-SUR in 2010. As re-accreditation approaches an evaluation of the career with the Brazilian and Argentinian national standards of accreditation was simulated due to their strong influence on the definition of the regional criteria. Institutional self-assessment was updated and compared with the accreditation indicators of the Brazilian and Argentinian agencies. The idea of quality of the accreditation system in Brazil emphasizes the training of the teaching staff while in Argentina emphasizes the teaching and learning processes. The career could achieve accreditation with the Argentinian parameters but should improve aspects of the academic training of their teachers to achieve accreditation in Brazil. This work made it possible to adjust the Development Plan of the Faculty of Veterinary Medicine.

  1. Determining the effects of cattle grazing treatments on Yosemite toads (Anaxyrus [=Bufo] canorus in montane meadows.

    Directory of Open Access Journals (Sweden)

    Susan K McIlroy

    Full Text Available Amphibians are experiencing a precipitous global decline, and population stability on public lands with multiple uses is a key concern for managers. In the Sierra Nevada Mountains (California, USA, managers have specifically identified livestock grazing as an activity that may negatively affect Yosemite toads due to the potential overlap of grazing with toad habitat. Grazing exclusion from Yosemite toad breeding and rearing areas and/or entire meadows have been proposed as possible management actions to alleviate the possible impact of cattle on this species. The primary objective of this study was to determine if different fencing treatments affect Yosemite toad populations. We specifically examined the effect of three fencing treatments on Yosemite toad breeding pool occupancy, tadpoles, and young of the year (YOY. Our hypothesis was that over the course of treatment implementation (2006 through 2010, Yosemite toad breeding pool occupancy and early life stage densities would increase within two fencing treatments relative to actively grazed meadows due to beneficial changes to habitat quality in the absence of grazing. Our results did not support our hypothesis, and showed no benefit to Yosemite toad presence or early life stages in fenced or partially fenced meadows compared to standard USDA Forest Service grazing levels. We found substantial Yosemite toad variation by both meadow and year. This variation was influenced by meadow wetness, with water table depth significant in both the tadpole and YOY models.

  2. The weight of «tradition» in multilateral commercial negotiations. The argentinian case during the Doha Round

    Directory of Open Access Journals (Sweden)

    Julieta Zelicovich

    2014-05-01

    Full Text Available The article studies the impact of ‘tradition’ as a variable inside the analyses of foreign policy. For that end, it considers a particular case, the participation of Argentina in multilateral commercial negotiations. The central argument signals that, for Argentina, the negotiating tradition has had an important role as a guidance in foreign policy actions regarding multilateral commercial negotiations, especially in the moments of crisis. In addition, that, within this tradition, the main variable in the configuration of Argentinian options has been the development strategy.

  3. Argentinian pistachio oil and flour: a potential novel approach of pistachio nut utilization.

    Science.gov (United States)

    Martínez, Marcela Lilian; Fabani, María Paula; Baroni, María Verónica; Huaman, Rocío Nahime Magrini; Ighani, Marcelo; Maestri, Damián M; Wunderlin, Daniel; Tapia, Alejandro; Feresin, Gabriela Egly

    2016-05-01

    In order to searching a potential novel approach to pistachio utilization, the chemical and nutritional quality of oil and flour from natural, roasted, and salted roasted pistachios from Argentinian cultivars were evaluated. The pistachio oil has high contents of oleic and linoleic acid (53.5 - 55.3, 29 - 31.4 relative abundance, respectively), tocopherols (896 - 916 μg/g oil), carotenoids (48 - 56 μg/g oil) and chlorophylls (41 - 70 μg/g oil), being a good source for commercial edible oil production. The processing conditions did not affect significantly the fatty acid and minor composition of pistachio oil samples. The content of total phenolic (TP) and flavonoids (FL) was not significantly modified by the roasting process, whereas free radical scavenging (DPPH radical) and antioxidant power decreased in a 20% approximately. Furthermore, salted roasted pistachio flour (SRPF) showed a significant decrease in TP and FL content in comparison to others samples. The phenolic profile of pistachio flours evaluated by LC-ESI-QTOF-MS. The major compounds identified were (+)-catechin (38 - 65.6 μg/g PF d.w.), gallic acid (23 - 36 μg/g PF d.w.) and cyanidin-3-O-galactoside (21 - 23 μg/g PF d.w.). The treatments effects on the phenolics constituents of pistachio flour. Roasting caused a significant reduction of some phenolics, gallic acid and (+)- catechin, and increased others, naringenin and luteolin. Salting and roasting of pistachio increased garlic acid and naringenin content. PMID:27407192

  4. Adrenocortical function in cane toads from different environments.

    Science.gov (United States)

    Hernández, Sandra E; Sernia, Conrad; Bradley, Adrian J

    2016-05-01

    The adrenocortical function of cane toads (Rhinella marina) exposed to different experimental procedures, as well as captured from different environments, was assessed by challenging the hypothalamic-pituitary-adrenal (HPA) axis. It was found that restriction stress as well as cannulation increased plasma corticosterone (B) levels for up to 12h. A single dose of dexamethasone (DEX 2mg/kg) significantly reduced B levels demonstrating its potential for use in the evaluation of the HPA axis in amphibia. We also demonstrate that 0.05 IU/g BW (im) of synthetic adrenocorticotropic hormone (ACTH) significantly increased plasma B levels in cane toads. Changes in size area of the cortical cells were positively associated with total levels of B after ACTH administration. We also found differences in adrenal activity between populations. This was assessed by a DEX-ACTH test. The animals captured from the field and maintained in captivity for one year at the animal house (AH) present the highest levels of total and free B after ACTH administration. We also found that animals from the front line of dispersion in Western Australia (WA) present the weakest adrenal response to a DEX-ACTH test. The animals categorized as long established in Queensland Australia (QL), and native in Mexico (MX), do not shown a marked difference in the HPA activity. Finally we found that in response to ACTH administration, females reach significantly higher levels of plasma B than males. For the first time the adrenocortical response in cane toads exposed to different experimental procedures, as well as from different populations was assessed systematically. PMID:26877241

  5. Ion transport by mitochondria-rich cells in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Ussing, H H; Spring, K R

    1987-01-01

    The optical sectioning video imaging technique was used for measurements of the volume of mitochondria-rich (m.r.) cells of the isolated epithelium of toad skin. Under short-circuit conditions, cell volume decreased by about 14% in response to bilateral exposure to Cl-free (gluconate substitution......) solutions, apical exposure to a sodium-free solution, or to amiloride. Serosal exposure to ouabain resulted in a large increase in volume, which could be prevented either by the simultaneous application of amiloride in the apical solution or by the exposure of the epithelium to bilateral Cl-free solutions...

  6. A challenge of regional integration: the Southern Argentinian pipeline enlargement; Desafio de integracao regional: ampliacao do gasoduto Sul-Argentino

    Energy Technology Data Exchange (ETDEWEB)

    Sardi, Oscar; Sosa, Damian [Transportadora de Gas del Sur S.A., Buenos Aires (Argentina); Duarte Filho, Arno [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2005-07-01

    The enlargement of the pipelines of Southern Argentina comprised the construction of around 500 km of 30' and 36' loops in the first semester of 2005 and presented many peculiarities. It has been the first enlargement of the argentinian pipeline system since the country's default statement, in 2001, and it has been financed and built by a bi national Brazilian-Argentinian consortium. It has also been the first time that a governmental trusteeship has been used in such an enterprise in Argentina to guarantee the necessary funds. The increasing demand of natural gas to industries and power generation plants brought about by Argentina's recent growth has stated the sense of urgency: the construction must be on duty in June 2005, ready to increase de flow of gas to the Provincia de Buenos Aires and Great Buenos Aires regions. This has represented also a technical challenge, due to the small time to built the loops, the geographical distribution of the construction, which extends from Patagonia to the Great Buenos Aires region and the meteorological conditions of the period of the construction. The article describes the negotiations done to assemble the construction's financial and managerial frameworks, the building and the solutions found to face the challenge and to meet the deadline. (author)

  7. Cane toads lack physiological enhancements for dispersal at the invasive front in Northern Australia

    Directory of Open Access Journals (Sweden)

    Christopher R. Tracy

    2011-11-01

    Many invasive species have evolved behavioural and morphological characteristics that facilitate their dispersal into new areas, but it is unclear how selection on this level of the phenotype filters through to the underlying physiology. Cane toads have been dispersing westward across northern tropical Australia for more than 70 years. Previous studies of cane toads at the invasive front have identified several behavioural, morphological and locomotory characteristics that have evolved to facilitate dispersal of toads. We assessed a range of physiological characteristics associated with locomotory abilities in toads from the long-established, east coast of Australia, from the invasive front, and from a site in between these locations. We measured time to exhaustion and respiratory gases of toads exercising on a treadmill, time to recovery from exhaustion, blood properties (lactate, haematocrit, haemoglobin, red blood cell count, blood cell volume, and muscle properties associated with locomotion (activities of the enzymes citrate synthase and lactate dehydrogenase, and pH buffering capacity. None of the measured physiological parameters supported the hypothesis that toads from the invasive front possess physiological adaptations that facilitate dispersal compared to toads from areas colonised in the past. The strongest difference among the three groups of toads, time to exhaustion, showed exactly the opposite trend; toads from the long-established populations in the east coast had the longest time to exhaustion. Successful colonisers can employ many characteristics to facilitate their dispersal, so the extent to which behaviour, morphology and physiology co-evolve remains an interesting question. However, in the present case at least, behavioural adaptations do not appear to have altered the organism's underlying physiology.

  8. The identity of the South African toad Sclerophrys capensis Tschudi, 1838 (Amphibia, Anura).

    Science.gov (United States)

    Ohler, Annemarie; Dubois, Alain

    2016-01-01

    The toad species Sclerophrys capensis Tschudi, 1838 was erected for a single specimen from South Africa which has never been properly studied and allocated to a known species. A morphometrical and morphological analysis of this specimen and its comparison with 75 toad specimens referred to five South African toad species allowed to allocate this specimen to the species currently known as Amietophrynus rangeri. In consequence, the nomen Sclerophrys must replace Amietophrynus as the valid nomen of the genus, and capensis as the valid nomen of the species. This work stresses the usefulness of natural history collections for solving taxonomic and nomenclatural problems.

  9. Sensory feedback and coordinating asymmetrical landing in toads.

    Science.gov (United States)

    Cox, S M; Gillis, Gary B

    2016-06-01

    Coordinated landing requires anticipating the timing and magnitude of impact, which in turn requires sensory input. To better understand how cane toads, well known for coordinated landing, prioritize visual versus vestibular feedback during hopping, we recorded forelimb joint angle patterns and electromyographic data from five animals hopping under two conditions that were designed to force animals to land with one forelimb well before the other. In one condition, landing asymmetry was due to mid-air rolling, created by an unstable takeoff surface. In this condition, visual, vestibular and proprioceptive information could be used to predict asymmetric landing. In the other, animals took off normally, but landed asymmetrically because of a sloped landing surface. In this condition, sensory feedback provided conflicting information, and only visual feedback could appropriately predict the asymmetrical landing. During the roll treatment, when all sensory feedback could be used to predict an asymmetrical landing, pre-landing forelimb muscle activity and movement began earlier in the limb that landed first. However, no such asymmetries in forelimb preparation were apparent during hops onto sloped landings when only visual information could be used to predict landing asymmetry. These data suggest that toads prioritize vestibular or proprioceptive information over visual feedback to coordinate landing. PMID:27247440

  10. Sensory feedback and coordinating asymmetrical landing in toads.

    Science.gov (United States)

    Cox, S M; Gillis, Gary B

    2016-06-01

    Coordinated landing requires anticipating the timing and magnitude of impact, which in turn requires sensory input. To better understand how cane toads, well known for coordinated landing, prioritize visual versus vestibular feedback during hopping, we recorded forelimb joint angle patterns and electromyographic data from five animals hopping under two conditions that were designed to force animals to land with one forelimb well before the other. In one condition, landing asymmetry was due to mid-air rolling, created by an unstable takeoff surface. In this condition, visual, vestibular and proprioceptive information could be used to predict asymmetric landing. In the other, animals took off normally, but landed asymmetrically because of a sloped landing surface. In this condition, sensory feedback provided conflicting information, and only visual feedback could appropriately predict the asymmetrical landing. During the roll treatment, when all sensory feedback could be used to predict an asymmetrical landing, pre-landing forelimb muscle activity and movement began earlier in the limb that landed first. However, no such asymmetries in forelimb preparation were apparent during hops onto sloped landings when only visual information could be used to predict landing asymmetry. These data suggest that toads prioritize vestibular or proprioceptive information over visual feedback to coordinate landing.

  11. Molecular characterization of MHC class II in the Australian invasive cane toad reveals multiple splice variants.

    Science.gov (United States)

    Lillie, Mette; Cui, Jian; Shine, Richard; Belov, Katherine

    2016-07-01

    The cane toad has gained notoriety for its invasion across the Australian landscape, with significant impacts on the native Australian fauna. The invasion has accelerated over time, with invading cane toads adapted for highly dispersive traits. This, however, has come at the cost of the immune system, with lower investment in some immune functions. To investigate the cane toad's immunogenetics, we characterized four major histocompatibility complex (MHC) class IIA and three MHC class IIB loci. Preliminary observations suggest very low allelic diversity at all loci. We also observed various splice isoforms. One isoform seen at one class IIA and two class IIB loci was missing exon 2, which is essential to peptide binding and presentation. The other isoform, observed at a class IIA locus, is likely to be a soluble MHC product. These results may suggest a significant role of alternative splicing of MHC loci in the Australian cane toad. PMID:27233954

  12. Towed Optical Assessment Device (TOAD) Data to Support Benthic Habitat Mapping since 2001

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Optical validation data were collected using a Tethered Optical Assessment Device (TOAD), an underwater sled equipped with an underwater digital video camera and...

  13. Vascular aspects of water uptake mechanisms in the toad skin: perfusion, diffusion, confusion

    DEFF Research Database (Denmark)

    Willumsen, Niels; Viborg, Arne L; Hillyard, Stanley D

    2007-01-01

    Blood cell flow (BCF) in the water absorbing "seat patch" region of toad skin was measured with laser Doppler flow cytometry. BCF of dehydrated toads increased by a factor of 6-8 when water contact was made and declined gradually as toads rehydrated. Water absorption was initially stimulated...... and declined in parallel with BCF. Water absorption measured during the initial rehydration period did not correlate with BCF and hydrated toads injected with AVT increased water absorption without an increase in BCF indicating the lack of an obligate relation between blood flow and water absorption...... coupling explains the greater absorption from dilute salt solutions. Rehydration from 10 mM CaCl2 was stimulated above that of DI water by a similar degree as with 50 mM NaCl suggesting the anion might control water permeability of the skin....

  14. Differences and Similarities among Parotoid Macrogland Secretions in South American Toads: A Preliminary Biochemical Delineation

    OpenAIRE

    Juliana Mozer Sciani; Cláudia Blanes Angeli; Antoniazzi, Marta M.; Carlos Jared; Daniel Carvalho Pimenta

    2013-01-01

    Amphibians are known by cutaneous glands, spread over the skin, containing toxins (proteins, peptides, biogenic amines, steroidal bufadienolides, and alkaloids) used as chemical defense against predators and microbial infection. Toads are characterized by the presence of parotoid macroglands. The common toads have lately been divided into two genera: Bufo (Europe, Asia, and Africa) and Rhinella (South America). Basal Rhaebo genus is exclusively of Central America and Amazon region. Although R...

  15. Temperature, hydric environment, and prior pathogen exposure alter the experimental severity of chytridiomycosis in boreal toads

    Science.gov (United States)

    Murphy, Peter J.; St-Hilaire, Sophie; Corn, Paul Stephen

    2011-01-01

    Prevalence of the pathogen Batrachochytrium dendrobatidis (Bd), implicated in amphibian population declines worldwide, is associated with habitat moisture and temperature, but few studies have varied these factors and measured the response to infection in amphibian hosts. We evaluated how varying humidity, contact with water, and temperature affected the manifestation of chytridiomycosis in boreal toads Anaxyrus (Bufo) boreas boreas and how prior exposure to Bd affects the likelihood of survival after re-exposure, such as may occur seasonally in long-lived species. Humidity did not affect survival or the degree of Bd infection, but a longer time in contact with water increased the likelihood of mortality. After exposure to ~106 Bd zoospores, all toads in continuous contact with water died within 30 d. Moreover, Bd-exposed toads that were disease-free after 64 d under dry conditions, developed lethal chytridiomycosis within 70 d of transfer to wet conditions. Toads in unheated aquaria (mean = 15°C) survived less than 48 d, while those in moderately heated aquaria (mean = 18°C) survived 115 d post-exposure and exhibited behavioral fever, selecting warmer sites across a temperature gradient. We also found benefits of prior Bd infection: previously exposed toads survived 3 times longer than Bd-naïve toads after re-exposure to 106 zoospores (89 vs. 30 d), but only when dry microenvironments were available. This study illustrates how the outcome of Bd infection in boreal toads is environmentally dependent: when continuously wet, high reinfection rates may overwhelm defenses, but periodic drying, moderate warming, and previous infection may allow infected toads to extend their survival.

  16. Biotic Resistance to an Alien Amphibian: Larval Competition between Japanese Frogs and Invasive Cane Toads

    Science.gov (United States)

    2016-01-01

    Understanding negative effects of native species on introduced taxa may suggest novel ways to control the invasive species by enhancing such effects. Previous studies have reported that the larvae of invasive cane toads (Rhinella marina) are suppressed by competition with the larvae of native anurans in Australia, but not in North America. We conducted laboratory trials to measure the effect of exposure to the larvae of Japanese frogs (Microhyla ornata, Fejervarya sakishimensis, Rhacophorus owstoni) on rates of survival, growth and development of cane toad tadpoles in Ishigaki Island, in southern Japan. Survival rates were not affected by native species, but competition with Dicroglossids and Rhacophorids (but not Microhylids) strongly reduced rates of growth and development in the tadpoles of cane toads. Dicroglossid tadpoles also reduced the body condition to toad tadpoles in addition to effects on SVL and mass. Encouraging populations of native frogs in toad-invaded areas of Japan thus may help to reduce the numbers of invasive cane toads. PMID:27253973

  17. Determination of heavy metals for the quality control in Argentinian herbal medicines by ETAAS and ICP-OES.

    Science.gov (United States)

    Gomez, María R; Cerutti, Soledad; Sombra, Lorena L; Silva, María F; Martínez, Luis D

    2007-06-01

    The determination of trace elements in Hypericum perforatum leaves and flowers, their teas, tinctures and tablets was carried out by Electrothermal Atomic Absorption Spectrometry (ETAAS) and Ultrasonic Nebulization System coupled to Inductively Coupled Plasma Optical Emission Spectrometry (USN-ICP-OES). Hypericum perforatum (St. John's wort), is a phytomedicine used for the treatment of depression. Samples were collected from different sources in the argentinian market. Heavy metals contents in the investigated samples were found at different levels. Chromium and cobalt were undetectable above their limits of detection in both liquid and solid samples; while aluminum, cadmium, lead, iron and vanadium were present in the majority of samples. The analytical results obtained for all metals indicate that they were present at concentration well below the acceptable daily intake recommended by the World Health Organization. Based on the results obtained in the present work, it is concluded that the present techniques are suitable for the routine determination of heavy metals concentration in phytopharmaceuticals.

  18. CEPF Western Ghats Special Series: Description of tadpole stages of the Malabar Tree Toad Pedostibes tuberculosis Gunther, 1875 (Anura: Bufonidae

    Directory of Open Access Journals (Sweden)

    K.P. Dinesh

    2014-10-01

    Full Text Available Pedostibes tuberculosus, the Malabar tree toad, was described 137 years ago from the Malabar region (now the coastal parts of Kerala of the Western Ghats. Since the description of this arboreal toad, not much information is available on the natural history, breeding habits and life cycle except for its description, range of distribution and advertisement call details. In the present account, the tadpole stages of this toad from Gosner tadpole Stage 21 to 45 are presented and the phytotelmatic mode of life of this toad has been confirmed by locating the tadpoles within the Ochlandra reed culm.

  19. Isotopic and fluid-inclusion constraints on the formation of polymetallic vein deposits in the central Argentinian Patagonia

    Science.gov (United States)

    Dejonghe, Léon; Darras, Benoît; Hughes, Guillermo; Muchez, Philippe; Scoates, James S.; Weis, Dominique

    2002-03-01

    The lead isotope compositions of galena and the fluid-inclusion systematics of nine barite-bearing polymetallic (Au, Ag, Pb, Zn) deposits of the central Argentinian Patagonia (Chubut and Rio Negro provinces) have been investigated to constrain the compositions and sources of the mineralizing fluids. Most of the deposits occur as veins, with less common wall-rock disseminations and/or stockworks, and are low-sulfidation epithermal deposits hosted in Jurassic volcanic rocks. Fluid-inclusion homogenization temperatures (Th) from quartz and sphalerite from the deposits fall within the range of 100-300 °C, with the highest measured average temperatures for the most eastern deposits (Mina Angela - 298 °C; Cañadón Bagual - 343 °C). The salinities of the hydrothermal fluids at all deposits were low to moderate (≤10.4 equiv. wt% NaCl). Three groups of ore deposits can be defined on the basis of 206Pb/204Pb ratios for galena and these show a general decrease from west to east (from 18.506 to 18.000). The central Argentinian Patagonia deposits have distinctly less radiogenic lead isotope compositions than similar deposits from Peru and Chile, except for the porphyry copper deposits of central and southern Peru. Galena from the Mina Angela deposit is characterized by very low radiogenic lead isotope compositions (18.000Precambrian basement. The geographic trend in lead isotope compositions of both galena and whole rocks indicates a crustal contribution which increases eastwards, also reflected in the strontium-neodymium isotope systematics of the host lavas. Finally, due to the lack of precise age determinations for the central Patagonian polymetallic deposits, a potential link with Andean porphyry copper systems remains an open question.

  20. The All Optical New Universal Gate Using TOAD

    Directory of Open Access Journals (Sweden)

    Goutam Kumar Maity

    2014-06-01

    Full Text Available Since the seventies of the past century the reversible logic has originated as an unconventional form of computing. It is new relatively in the area of extensive applications in quantum computing, low power CMOS, DNA computing, digital signal processing (DSP, nanotechnology, communication, optical computing, computer graphics, bio information, etc .Here we present and configure a new TAND gate in all-optical domain and also in this paper we have explained their principle of operations and used a theoretical model to fulfil this task, finally supporting through numerical simulations. In the field of ultra-fast all-optical signal processing Terahertz Optical Asymmetric Demultiplexer (TOAD, semiconductor optical amplifier (SOA-based, has an important function. The different logical (composing of Boolean function operations can be executed by designed circuits with TAND gate in the domain of universal logic-based information processing.

  1. Influence of demography and environment on persistence in toad populations

    Science.gov (United States)

    Lambert, Brad A.; Schorr, Robert A.; Schneider, Scott C.; Muths, Erin L.

    2016-01-01

    Effective conservation of rare species requires an understanding of how potential threats affect population dynamics. Unfortunately, information about population demographics prior to threats (i.e., baseline data) is lacking for many species. Perturbations, caused by climate change, disease, or other stressors can lead to population declines and heightened conservation concerns. Boreal toads (Anaxyrus boreas boreas) have undergone rangewide declines due mostly to the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), with only a few sizable populations remaining in the southern Rocky Mountains, USA, that are disease-free. Despite the apparent region-wide occurrence of Bd, our focal populations in central Colorado were disease free over a 14-year capture-mark-recapture study until the recent discovery of Bd at one of the sites. We used recapture data and the Pradel reverse-time model to assess the influence of environmental and site-specific conditions on survival and recruitment. We then forecast changes in the toad populations with 2 growth models; one using an average lambda value to initiate the projection, and one using the most recent value to capture potential effects of the incursion of disease into the system. Adult survival was consistently high at the 3 sites, whereas recruitment was more variable and markedly low at 1 site. We found that active season moisture, active season length, and breeding shallows were important factors in estimating recruitment. Population growth models indicated a slight increase at 1 site but decreasing trends at the 2 other sites, possibly influenced by low recruitment. Insight into declining species management can be gained from information on survival and recruitment and how site-specific environmental factors influence these demographic parameters. Our data are particularly useful because they provide baseline data on demographics in populations before a disease outbreak and enhance our ability to detect changes

  2. Determination of pesticide aerial drift and associated effects to the endangered Wyoming toad (Bufo baxteri) at Mortenson and Hutton National Wildlife Refuges and potential reintroduction sites

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The endangered Wyoming toad is confined to Mortenson National Wildlife Refuge (NWR) in southeast Wyoming. Reasons for the decline of the toad are unknown, but it is...

  3. Effects of amphibian chytrid fungus on individual survival probability in wild boreal toads

    Science.gov (United States)

    Pilliod, D.S.; Muths, E.; Scherer, R. D.; Bartelt, P.E.; Corn, P.S.; Hossack, B.R.; Lambert, B.A.; Mccaffery, R.; Gaughan, C.

    2010-01-01

    Chytridiomycosis is linked to the worldwide decline of amphibians, yet little is known about the demographic effects of the disease. We collected capture-recapture data on three populations of boreal toads (Bufo boreas [Bufo = Anaxyrus]) in the Rocky Mountains (U.S.A.). Two of the populations were infected with chytridiomycosis and one was not. We examined the effect of the presence of amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]; the agent of chytridiomycosis) on survival probability and population growth rate. Toads that were infected with Bd had lower average annual survival probability than uninfected individuals at sites where Bd was detected, which suggests chytridiomycosis may reduce survival by 31-42% in wild boreal toads. Toads that were negative for Bd at infected sites had survival probabilities comparable to toads at the uninfected site. Evidence that environmental covariates (particularly cold temperatures during the breeding season) influenced toad survival was weak. The number of individuals in diseased populations declined by 5-7%/year over the 6 years of the study, whereas the uninfected population had comparatively stable population growth. Our data suggest that the presence of Bd in these toad populations is not causing rapid population declines. Rather, chytridiomycosis appears to be functioning as a low-level, chronic disease whereby some infected individuals survive but the overall population effects are still negative. Our results show that some amphibian populations may be coexisting with Bd and highlight the importance of quantitative assessments of survival in diseased animal populations. Journal compilation. ?? 2010 Society for Conservation Biology. No claim to original US government works.

  4. The Fourier Imaging X-ray Spectrometer (FIXS) for the Argentinian, Scout-launched satelite de Aplicaciones Cienficas-1 (SAC-1)

    Science.gov (United States)

    Dennis, Brian R.; Crannell, Carol JO; Desai, Upendra D.; Orwig, Larry E.; Kiplinger, Alan L.; Schwartz, Richard A.; Hurford, Gordon J.; Emslie, A. Gordon; Machado, Marcos; Wood, Kent

    1988-01-01

    The Fourier Imaging X-ray Spectrometer (FIXS) is one of four instruments on SAC-1, the Argentinian satellite being proposed for launch by NASA on a Scout rocket in 1992/3. The FIXS is designed to provide solar flare images at X-ray energies between 5 and 35 keV. Observations will be made on arcsecond size scales and subsecond time scales of the processes that modify the electron spectrum and the thermal distribution in flaring magnetic structures.

  5. Dehydration hardly slows hopping toads (Rhinella granulosa) from xeric and mesic environments.

    Science.gov (United States)

    Prates, Ivan; Angilleta, Michael J; Wilson, Robbie S; Niehaus, Amanda C; Navas, Carlos A

    2013-01-01

    The locomotor capacity of amphibians depends strongly on temperature and hydration. Understanding the potential interactions between these variables remains an important challenge because temperature and water availability covary strongly in natural environments. We explored the effects of temperature and hydration on the hopping speeds of Rhinella granulosa, a small toad from the semiarid Caatinga and the Atlantic Rain Forest in Brazil. We asked whether thermal and hydric states interact to determine performance and whether toads from the Caatinga differ from their conspecifics from the Atlantic Forest. Both dehydration and cooling impaired hopping speed, but effects were independent of one another. In comparison to performances of other anurans, the performance of R. granulosa was far less sensitive to dehydration. Consequently, dehydrated members of this species may be able to sustain performance through high body temperatures, which agrees with the exceptional heat tolerance of this species. Surprisingly, toads from both the Caatinga and the Atlantic Forest were relatively insensitive to dehydration. This observation suggests that migration or gene flow between toads from the forest and those from a drier region occurred or that toads from a dry region colonized the forest secondarily. PMID:23799839

  6. Contribution to the study of immune hemolysis by toad complement

    Directory of Open Access Journals (Sweden)

    Marisa Gennari

    1982-09-01

    Full Text Available EA (sheep erythrocytes carrying rabbit antibody are lysed by toad complement under optimal conditions which include a low concentration of cells (1.54 x 10*8/ml, a low temperature of incubation (30°C and the same amounts of Ca++ and Mg++ as required for the titration of guinea-pig complement. Kinetic studies of the role of cations mentioned above in immune lysis by toad C have disclosed a fundamental difference as compared to guinea-pig C. In a limited complement system, the lysis by amphibian C is completely blocked by EDTA, even when the chelating agent is added as late as 15 minutes after zero-time. Inhibition by EGTA is only partial and the findings suggest that Mg++ is required not only at the beginning, but also at late stages of the lytic process. It has been speculated that the activation of amphibian complement proceeds mainly by the alternative pathway.EA (eritrócitos de carneiro, sensibilizados com anticorpos de coelho são lisados por complemento de sapo em condições ótimas, que consistem no uso de uma baixa concentração de células (1.54 x 10*8/ml, incubação a baixa temperatura (30°C e as mesmas quantidades de Ca++ e de Mg++, requeridas para a titulação da atividade hemolítica do complemento de cobaia. Estudos cinéticos do efeito dos cátions mencionados acima na imune-lise produzida pelo complemento de sapo revelam uma diferença fundamental com relação ao complemento de cobaía. Num sistema limitado pela quantidade de complemento, a lise pelo C de anfíbio é totalmente bloqueada por EDTA, mesmo quando a adição do agente quelante é feita após 15 minutos, ao passo que com EGTA o bloqueio é apenas parcial. Os achados experimentais sugerem que Mg++ seja requerido não apenas no estágio inicial, mas também em estágios tardios do processo lítico e permitem especular que a ativação do complemento de anfíbio se processa predominantemente pela via alternativa.

  7. Thermal ecology of the post-metamorphic Andean toad (Rhinella spinulosa) at elevation in the monte desert, Argentina.

    Science.gov (United States)

    Sanabria, Eduardo A; Rodríguez, César Y; Vergara, Cristina; Ontivero, Emanuel; Banchig, Mariana; Navas, Ana L; Herrera-Morata, Mario A; Quiroga, Lorena B

    2015-08-01

    Rhinella spinulosa is an anuran toad species distributed latitudinal and altitudinal (1200-5000m) from Peru to Argentina, inhabiting mountain valleys in the Andes. Considering the broad range of habitats where they live, it is important to understand the thermal physiological mechanisms, thermal tolerances and physiological adaptations for surviving in rigorous environments. We investigated the thermal parameters (field body temperature, selected body temperature, locomotor performance in field and laboratory conditions, and thermal extremes) during diurnal activity for a population of juvenile, post-metamorphosed toads (Rhinella spinulosa) from the Monte Desert of San Juan, Argentina. Post-metamorphic toads are active from approximately 1100-1900 (in contrast to nocturnal adult toads). Our findings show that these toads have a wide thermal tolerance range, ranging from a critical thermal maximum of 36.9°C to crystallization temperatures below 0°C. During their active period, toads always showed suboptimal thermal conditions for locomotion. Despite the suboptimal condition for the locomotion, diurnal activity is likely to confer thermal advantages, allowing them to search for food and increase digestion and growth rates. We also found that the toads are capable of super-cooling, which prevents mortality from freezing when the environmental temperatures drop below 0°C. The environmental temperatures are below zero at night, when toads are inactive and take refuge under rocks. In summary, this toad population demonstrates high thermal plasticity, as shown by a relatively high level of activity sustained over a wide range of ambient temperature (~35°C). These thermal adaptations allow this species of juvenile toads to inhabit a wide range of altitudes and latitudes.

  8. Mapping the Relative Probability of Common Toad Occurrence in Terrestrial Lowland Farm Habitat in the United Kingdom.

    Directory of Open Access Journals (Sweden)

    Rosie D Salazar

    Full Text Available The common toad (Bufo bufo is of increasing conservation concern in the United Kingdom (UK due to dramatic population declines occurring in the past century. Many of these population declines coincided with reductions in both terrestrial and aquatic habitat availability and quality and have been primarily attributed to the effect of agricultural land conversion (of natural and semi-natural habitats to arable and pasture fields and pond drainage. However, there is little evidence available to link habitat availability with common toad population declines, especially when examined at a broad landscape scale. Assessing such patterns of population declines at the landscape scale, for instance, require an understanding of how this species uses terrestrial habitat.We intensively studied the terrestrial resource selection of a large population of common toads in Oxfordshire, England, UK. Adult common toads were fitted with passive integrated transponder (PIT tags to allow detection in the terrestrial environment using a portable PIT antenna once toads left the pond and before going into hibernation (April/May-October 2012 and 2013. We developed a population-level resource selection function (RSF to assess the relative probability of toad occurrence in the terrestrial environment by collecting location data for 90 recaptured toads.The predicted relative probability of toad occurrence for this population was greatest in wooded habitat near to water bodies; relative probability of occurrence declined dramatically > 50 m from these habitats. Toads also tended to select habitat near to their breeding pond and toad occurrence was negatively related to urban environments.

  9. Population and habitat viability assessment for the Wyoming toad (Bufo baxteri): Final workshop report

    Science.gov (United States)

    2001-01-01

    The Wyoming toad was discovered by Dr. George Baxter in 1946 and was originally known as Bufo hemiophrys baxteri until 1998 when it was given full species status as Bufo baxteri. The toad is thought to be a glacial relic always found only in the Laramie Basin. It was originally known from many breeding sites in the floodplains of the Big and Little Laramie Rivers. Later, after irrigation practices changed the nature of the floodpains, it was found along margins of ponds and small seepage lakes between 7,000 and 7,500 feet. Baxter and others monitored breeding sites for more than 30 years, with few toads seen or heard from 1975 to 1979. An extensive survey of the Laramie Basin in 1980 found only one population.

  10. Optimizing the performance of TOAD by changing the wavelength and power of control pulse

    Institute of Scientific and Technical Information of China (English)

    Liangsheng Wen(温亮生); Peng Zuo(左鹏); Jian Wu(伍剑); Jintong Lin(林金桐)

    2003-01-01

    The performance of terahertz optical asymmetric demultiplexer (TOAD) has been studied by modelling the semiconductor optical amplifier (SOA) in which the intraband effects had been taken into account.Numerical results are coincident with the experiment results. We interpret why there are three peaks in the switching window, which has never been reported before. In addition, we put forward the definition of the flatness of the switching window of TOAD for the first time By analysing the different phase of clockwise and counter clockwise signal pulse changed by SOA, appropriate peak power of control pulse and wavelength of signal and control pulse have been calculated in order to obtain large output power and flat switching window of TOAD.

  11. Effects of age, weight, hormones, and hibernation on breeding success in boreal toads (Bufo boreas boreas).

    Science.gov (United States)

    Roth, T L; Szymanski, D C; Keyster, E D

    2010-03-01

    The goals of this study were to test the effects of exogenous hormones and hibernation on breeding behavior and gamete release by boreal toads (Bufo boreas boreas). Each year, a subset of 77 toads was hibernated and then paired with hibernated or nonhibernated mates and treated with luteinizing hormone releasing hormone analogue (LHRHa), human chorionic gonadotropin (hCG), or left untreated. Amplexus and egg and sperm production were recorded. At 1 yr of age, only 19% of pairs exhibited amplexus, and no sperm or eggs were produced. At 2 and 3 yr of age, most male toads treated with LHRHa exhibited amplexus (56.9% and 100%, respectively). Among 2-yr-old males, amplexus was more prevalent (Pbreeding success, males should be hibernated and treated with LHRHa. In contrast, female productivity was enhanced by improving their body condition instead of subjecting them to hibernation prior to LHRHa treatment.

  12. Anticipatory motor patterns limit muscle stretch during landing in toads.

    Science.gov (United States)

    Azizi, Emanuel; Abbott, Emily M

    2013-02-23

    To safely land after a jump or hop, muscles must be actively stretched to dissipate mechanical energy. Muscles that dissipate energy can be damaged if stretched to long lengths. The likelihood of damage may be mitigated by the nervous system, if anticipatory activation of muscles prior to impact alters the muscle's operating length. Anticipatory motor recruitment is well established in landing studies and motor patterns have been shown to be modulated based on the perceived magnitude of the impact. In this study, we examine whether motor recruitment in anticipation of landing can serve a protective function by limiting maximum muscle length during a landing event. We use the anconeus muscle of toads, a landing muscle whose recruitment is modulated in anticipation of landing. We combine in vivo measurements of muscle length during landing with in vitro characterization of the force-length curve to determine the muscle's operating length. We show that muscle shortening prior to impact increases with increasing hop distance. This initial increase in muscle shortening functions to accommodate the larger stretches required when landing after long hops. These predictive motor strategies may function to reduce stretch-induced muscle damage by constraining maximum muscle length, despite variation in the magnitude of impact. PMID:23256184

  13. Multiple paternity in a viviparous toad with internal fertilisation

    Science.gov (United States)

    Sandberger-Loua, Laura; Feldhaar, Heike; Jehle, Robert; Rödel, Mark-Oliver

    2016-08-01

    Anurans are renowned for a high diversity of reproductive modes, but less than 1 % of species exhibit internal fertilisation followed by viviparity. In the live-bearing West African Nimba toad ( Nimbaphrynoides occidentalis), females produce yolk-poor eggs and internally nourish their young after fertilisation. Birth of fully developed juveniles takes place after 9 months. In the present study, we used genetic markers (eight microsatellite loci) to assign the paternity of litters of 12 females comprising on average 9.7 juveniles. In 9 out of 12 families (75 %), a single sire was sufficient; in three families (25 %), more than one sire was necessary to explain the observed genotypes in each family. These findings are backed up with field observations of male resource defence (underground cavities in which mating takes place) as well as coercive mating attempts, suggesting that the observed moderate level of multiple paternity in a species without distinct sperm storage organs is governed by a balance of female mate choice and male reproductive strategies.

  14. Effect of stretch on passive transport in toad urinary bladder.

    Science.gov (United States)

    Lief, P D; Mutz, B F; Bank, N

    1976-06-01

    In order to gain further information about the effect of stretch on the urinary bladder of the toad, transepithelial movement of radioactive sucrose, chloride, and urea was measured across bladder sacs during acute changes in the internal volume. Short-circuit current (SCC) and total tissue conductance (Kt) were also measured in each experiment. It was found that sudden large increases or smaller graded increases in volume resulted in a consistent fall in the tracer permeability (P*) of all three isotopes. However, this fall was due entirely to the larger area term in the calculation of P* rather than any real change in isotope movement. When total diffusion (TD) of each isotope was calculated by a method that eliminated the changes in surface area, it was apparent that stretch produced no significant effects on the transepithelial movement of any of these three molecules. Large stretch also resulted in parallel increases in SCC and Kt in most bladders. We conclude from these observations that the intercellular pathway for sucrose and chloride and the transcellular pathway for urea are unaltered by degrees of stretch that enhance SCC and sodium transport. By inference, the observed increases in Kt appear to represent changes in specific active pathway conductance (Ka), and may relate importantly to the changes in sodium transport. PMID:820207

  15. Nux Vomica 200 CH reduced acute hypnotic effect of alcohol in young toads

    OpenAIRE

    Nirmal Sukul; Arniban Sukul; Indrani Chakraborty

    2012-01-01

    Potentized Nux Vomica has been reported to produce antialcoholic effect in mice, rats and toads. The effect relates to consumption of alcohol and alcohol-induced loss of righting reflex (RR). RR’s maintain normal erect posture of an animal and are centrally controlled in the midbrain. In the present study young toads, Duttaphrynus melanostictus were first treated with Nux vomica 200 CH and then partially immersed in 209 mM ethanol solution in such a way that their head remained above t...

  16. New regional record and notes on historical specimens of Gunther Toad Duttaphrynus hololius with comments on other southeastern Indian congeners

    Directory of Open Access Journals (Sweden)

    B. Srinivasulu

    2013-09-01

    Full Text Available We report on the finding of the Günther Toad Duttaphrynus hololius from Visakhapatnam and discuss aspects of its distribution based on our species distribution modeling. We also provide data on historically collected specimens and refine its intra-specific variation, provide an up-to-date chresonymy and comment on the validity of earlier reported diagnosis. Lastly, we remark on some misidentification-mediated dubious southern Indian records of another, related congener, the Marbled Toad D. stomaticus and correct some misallocations by referring them to another syntopic congener, the Dwarf Toad D. scaber.

  17. Ultrastructure of the renal juxtaglomerular complex and peripolar cells in the axolotl (Ambystoma mexicanum) and toad (Bufo marinus).

    Science.gov (United States)

    Hanner, R H; Ryan, G B

    1980-05-01

    Renal juxtaglomerular regions were examined in the axolotl (Ambystoma mexicanum and toad (Bufo marinus). Prominent granulated peripolar epithelial cells were found surrounding the origin of the glomerular tuft in the axolotl. These cells resembled the peripolar cells recently discovered in mammalian species. They contained multiple electron-dense cytoplasmic granules, some of which showed a paracrystalline substructure and signs of exocytoxic activity. Such cells were difficult to find and smaller in the toad. In contrast, granulated juxtaglomerular arteriolar myoephithelial cells were much more readily found and larger in the toad than in the axolotl. No consistent differences were noted in juxtaglomerular cells or their granules in response to changes in environmental chloride concentration.

  18. Immune response varies with rate of dispersal in invasive cane toads (Rhinella marina.

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    Gregory P Brown

    Full Text Available What level of immunocompetence should an animal maintain while undertaking long-distance dispersal? Immune function (surveillance and response might be down-regulated during prolonged physical exertion due to energy depletion, and/or to avoid autoimmune reactions arising from damaged tissue. On the other hand, heightened immune vigilance might be favored if the organism encounters novel pathogens as it enters novel environments. We assessed the links between immune defense and long-distance movement in a population of invasive cane toads (Rhinella marina in Australia. Toads were radio-tracked for seven days to measure their activity levels and were then captured and subjected to a suite of immune assays. Toads that moved further showed decreased bacteria-killing ability in their plasma and decreased phagocytic activity in their whole blood, but a heightened skin-swelling response to phytohemagglutinin. Baseline and post-stress corticosterone levels were unrelated to distance moved. Thus, long-distance movement in cane toads is associated with a dampened response in some systems and enhanced response in another. This pattern suggests that sustained activity is accompanied by trade-offs among immune components rather than an overall down or up-regulation. The finding that high mobility is accompanied by modification of the immune system has important implications for animal invasions.

  19. Toad Glandular Secretions and Skin Extractions as Anti-Inflammatory and Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Ji Qi

    2014-01-01

    Full Text Available Toad glandular secretions and skin extractions contain many natural agents which may provide a unique resource for novel drug development. The dried secretion from the auricular and skin glands of Chinese toad (Bufo bufo gargarizans is named Chansu, which has been used in Traditional Chinese Medicine (TCM for treating infection and inflammation for hundreds of years. The sterilized hot water extraction of dried toad skin is named Huachansu (Cinobufacini which was developed for treating hepatitis B virus (HBV and several types of cancers. However, the mechanisms of action of Chansu, Huachansu, and their constituents within are not well reported. Existing studies have suggested that their anti-inflammation and anticancer potential were via targeting Nuclear Factor (NF-κB and its signalling pathways which are crucial hallmarks of inflammation and cancer in various experimental models. Here, we review some current studies of Chansu, Huachansu, and their compounds in terms of their use as both anti-inflammatory and anticancer agents. We also explored the potential use of toad glandular secretions and skin extractions as alternate resources for treating human cancers in combinational therapies.

  20. Etomidate anaesthesia by immersion in oriental fire-bellied toads (Bombina orientalis).

    Science.gov (United States)

    d'Ovidio, D; Spadavecchia, C; Angeli, G; Adami, C

    2015-10-01

    The objective of the present study was to evaluate the efficacy and the safety of etomidate anaesthesia by immersion technique in Bombina orientalis. The study comprised two phases. The first phase was carried out to identify the etomidate concentration capable of producing anaesthetic induction, as well as surgical anaesthesia, in the toads. The second phase was aimed at testing that concentration in eight additional animals. Etomidate administered via immersion at a concentration of 37.5 mg/L produced effective anaesthesia in oriental fire-bellied toads. The average duration of surgical anaesthesia was 20 min. All the toads enrolled in the study survived the anaesthesia and long-term complications did not occur. However, undesired side-effects, namely itching, myoclonus and prolonged recovery, were noticed during the perianaesthetic period. The authors concluded that etomidate anaesthesia by immersion, at a concentration of 37.5 mg/L, is suitable in oriental fire-bellied toads and produces anaesthesia of a depth and duration that is sufficient to allow the completion of various experimental procedures, without resulting in lethal complications. However, the occurrence of undesired side-effects opens a debate on the safety of this anaesthetic technique, and imposes the need for further investigation prior to proposing the latter for routine laboratory practice.

  1. DIET OF THE SOUTHERN TOAD (BUFO TERRESTRIS) FROM THE SOUTHERN EVERGLADES

    Science.gov (United States)

    We examined the diet of a February-May sample of the southern toad (Bufo terrestris) from the Everglades National Park. Above the familial level, 13 taxa were consumed, but ants (Hymenoptera) and beetles (Coleoptera) were consumed most by, and in the greatest number of sto...

  2. Baroreceptor control of heart rate in the awake toad: peripheral autonomic effectors and arterial baroreceptor areas.

    Science.gov (United States)

    Bianchi-da-Silva, L M; Menescal-de-Oliveira, L; Hoffmann, A

    2000-04-12

    Systemic injection of sodium nitroprusside (30 microg/kg, i.v.) in the awake Bufo paracnemis toad induced a fall in arterial blood pressure and tachycardia. This tachycardia, but not the hypotension, was significantly reduced in toads with bilateral electrolytic lesion of the caudal and commissural regions of the solitary tract nucleus and in animals with transection of the spinal cord, 2 mm below the obex. This indicates that the tachycardia is reflex, depends on the integrity of the solitary tract nucleus and is due to descending spinal autonomic activation. Pretreatment with propranolol (4 mg/kg, i.v.) significantly reduced the tachycardia but did not block it completely, showing the importance of beta-adrenoceptors in its genesis. The reflex increase in heart rate induced by nitroprusside was not statistically significant in animals with bilateral section of the laryngeal nerve, whose baroreceptor fibers originate from the pulmocutaneous artery or in animals in which the bilateral section of the laryngeal nerve was performed together with section of the glossopharyngeal nerves, which incorporate fibers originating from the carotid labyrinth. The reduction of the reflex tachycardia was significant in toads with aortic arch denervation alone or combined with section of the laryngeal nerves or in animals with complete denervation of the three baroreceptors areas. These results suggest that the region of the aortic arch, when submitted to unloading, is the most important baroreceptor zone for cardiac compensation in toads.

  3. Diagnostic histological findings in Yosemite toads (Bufo canorus) from die-off in the 1970s

    Science.gov (United States)

    Green, D.E.; Sherman, C.K.

    2001-01-01

    Twelve adult and 25 larval Yosemite toad (Bufo canorus) specimens from the eastern Sierra Nevada of California were examined histologically for evidence of infectious, toxicological, and degenerative diseases. The preserved toads were selected from 21 that had been salvaged or collected during a die-off in 1976-1979 that immediately preceded a population decline. Causes of death of four toads were determined histologically; clinical signs and field observations suggested causes of death of three more. Four toads died of infectious diseases, including chytridiomycosis of the skin (N = 1), bacillary septicemia (N = 2), and combined chytridiomycosis and bacterial septicemia (N = 1). Infections by a funguslike organism (Dermosporidium penneri), renal myxozoa (Leptotheca ohlmacheri), larval Rhabdias, various gastrointestinal nematodes, urinary bladder flukes, and lung flukes were detected in five specimens. No evidence of degenerative diseases, virus infections, or intoxications was found. The variety of lethal diseases and our inability to determine the causes of death of five specimens suggests that one or more histologically undetectable diseases or intoxications may have also contributed to the deaths and population decline.

  4. ACTION OF PROGESTERONE ON THE DEPOLARIZATION OF THE MEMBRANE POTENTIAL IN TOAD OOCYTES INDUCED BY LEUCINE

    Institute of Scientific and Technical Information of China (English)

    WANGYu-Feng

    1989-01-01

    The depolarization of the membrane potential in toad oocytes induced by leucine was found in our previous experiment. In this paper, a possible action or progesterone in the process was further investigated. After oocytes had been incubated for 16 to 24 hours with

  5. EFFECTS OF AMINO ACIDS ON THE MEMBRANE POTENTIAL OF TOAD OOCYTES AND THE MECHANISMS INVOLVED

    Institute of Scientific and Technical Information of China (English)

    WANGYu-Feng; CHENGJiun; CHENGZhi-Ping

    1989-01-01

    The etTects of 23 amino acids on the membrane potential of toad ( Bufo bufo gargarizans ) oocytes and the mechanisms involved were investigated in vitro by means of microelectrode. At a concentration of I mmol/L-alanine, leucine and lyaine induced signfiant depolarization, and tryptophan provoked a marked hyperpolarization during

  6. Tetrodotoxin and its analogues in extracts from the toad Atelopus oxyrhynchus (family: Bufonidae).

    Science.gov (United States)

    Yotsu-Yamashita, M; Mebs, D; Yasumoto, T

    1992-11-01

    Tetrodotoxin and its analogues, 4-epitetrodotoxin and 4,9-anhydrotetrodotoxin, were detected in the toad Atelopus oxyrhynchus by HPLC analysis. The toxin and its analogues were still present in a specimen which lived 3.5 years in captivity. PMID:1336632

  7. Determination of impacts on the endangered Wyoming toad (Bufo baxteri) at Mortenson National Wildlife Refuge from ammonium nitrate concentrations

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The endangered Wyoming toad (Bufo baxteri) is found only as a reintroduced population at Mortenson NWR in the Laramie Plains of southeast Wyoming. Reasons for the...

  8. Sodium recirculation and isotonic transport in toad small intestine.

    Science.gov (United States)

    Nedergaard, S; Larsen, E H; Ussing, H H

    1999-04-01

    Isolated small intestine of toad (Bufo bufo) was mounted on glass tubes for perfusion studies with oxygenated amphibian Ringer's solution containing glucose and acetate. Under open-circuit conditions (Vt = -3.9 +/- 1.8 mV, N = 14) the preparation generated a net influx of 134Cs+. The time course of unidirectional 134Cs+-fluxes was mono-exponential with similar rate constants for influx and outflux when measured in the same preparation. The flux-ratio was time invariant from the beginning of appearance of the tracers to steady state was achieved. Thus, just a single pathway, the paracellular pathway, is available for transepithelial transport of Cs+. From the ratio of unidirectional Cs+-fluxes the paracellular force was calculated to be, 18.2 +/- 1.5 mV (N = 6), which is directed against the small transepithelial potential difference. The paracellular netflux of cesium ions, therefore, is caused by solvent drag. The flux of 134Cs+ entering and trapped by the cells was of a magnitude similar to that passing the paracellular route. Therefore, independent of the convective flux of 134Cs+, every second 134Cs+ ion flowing into the lateral space was pumped into the cells rather than proceeding, via the low resistance pathway, to the serosal bath. It is thus indicated that the paracellular convective flow of 134Cs+ is driven by lateral Na+/K+-pumps. Transepithelial unidirectional 42K+ fluxes did not reach steady state within an observation period of 70 min, indicating that components of the fluxes in both directions pass the large cellular pool of potassium ions. The ratio of unidirectional 24Na+ fluxes was time-variant and declined from an initial value of 3.66 +/- 0.34 to a significantly smaller steady-state value of 2.57 +/- 0.26 (P water-filled pores. With a new set of equations, the fraction of the sodium flux passing the basement membrane barrier of the lateral space that is recirculated through the cellular compartment is estimated. This fraction was, on average, 0

  9. Use of local visual cues for spatial orientation in terrestrial toads (Rhinella arenarum): The role of distance to a goal.

    Science.gov (United States)

    Daneri, M Florencia; Casanave, Emma B; Muzio, Rubén N

    2015-08-01

    The use of environmental visual cues for navigation is an ability present in many groups of animals. The effect of spatial proximity between a visual cue and a goal on reorientation in an environment has been studied in several vertebrate groups, but never previously in amphibians. In this study, we tested the use of local visual cues (beacons) to orient in an open field in the terrestrial toad (Rhinella arenarum). Experiment 1 showed that toads could orient in space using 2 cues located near the rewarded container. Experiment 2 used only 1 cue placed at different distances to the goal and revealed that learning speed was affected by the proximity to the goal (the closer the cue was to the goal, the faster toads learned its location). Experiment 3 showed that the position of a cue results in a different predictive value. Toads preferred cues located closer to the goal more than those located farther away as a reference for orientation. Present results revealed, for the first time, that (a) toads can learn to orient in an open space using visual cues, and that (b) the effect of spatial proximity between a cue and a goal, a learning phenomenon previously observed in other groups of animals such as mammals, birds, fish, and invertebrates, also affects orientation in amphibians. Thus, our results suggest that toads are able to employ spatial strategies that closely parallel those described in other vertebrate groups, supporting an early evolutionary origin for these spatial orientation skills.

  10. Spatial and temporal ecology of oak toads (Bufo quercicus) on a Florida landscape.

    Energy Technology Data Exchange (ETDEWEB)

    Greenberg, Cathryn, H.; Tanner, George, W.

    2005-12-01

    ABSTRACT: We used data from 10 years of continuous, concurrent monitoring of oak toads at eight isolated, ephemeral ponds in Florida longleaf pine-wiregrass uplands to address: (1) did weather variables affect movement patterns of oak toads?; (2) did pond hydrology and the condition of surrounding uplands affect pond selection by adults or juvenile recruitment?; (3) were population trends evident?; and (4) did a classical metapopulation model best represent their population ecology? Of 4076 oak toads captured, 92.2% were adults. Substantial (n _ 30 exiting juveniles) recruitment occurred only three times (once each at three ponds during two years). Males outnumbered females (average for all years 2.3:1). Most captures occurred during May–September. Adult captures during June–August increased with heavier rainfall but were not influenced by the durations of preceding dry periods. Movement patterns of metamorphs suggested that oak toads emigrated when moisture conditions become favorable. Pond use by adults was correlated with maximum change in pond depth (May–September). Juvenile recruitment was negatively correlated with minimum pond depth and the number of weeks since a pond was last dry, and positively correlated with the maximum number of weeks a pond held water continuously. The number of breeding adults and juvenile recruitment were highest at ponds within the hardwood-invaded upland matrix. The direction of most immigrations and emigrations was nonrandom, but movement occurred from all directions, and the mean direction of pond entry and exit did not always correspond. A total of 21.1% of individuals was recaptured; 13.3% of first captures were recaptured during the same year, and 7.7% during a subsequent year. Only 1.9% of captured oak toads moved among ponds, mostly within a distance of 132 m. We did not detect adult population trends over the 10- yr studied. Presence or absence at ponds in any given year was a poor indicator of overall use. We saw

  11. Depth perception in frogs and toads a study in neural computing

    CERN Document Server

    House, Donald

    1989-01-01

    Depth Perception in Frogs and Toads provides a comprehensive exploration of the phenomenon of depth perception in frogs and toads, as seen from a neuro-computational point of view. Perhaps the most important feature of the book is the development and presentation of two neurally realizable depth perception algorithms that utilize both monocular and binocular depth cues in a cooperative fashion. One of these algorithms is specialized for computation of depth maps for navigation, and the other for the selection and localization of a single prey for prey catching. The book is also unique in that it thoroughly reviews the known neuroanatomical, neurophysiological and behavioral data, and then synthesizes, organizes and interprets that information to explain a complex sensory-motor task. The book will be of special interest to that segment of the neural computing community interested in understanding natural neurocomputational structures, particularly to those working in perception and sensory-motor coordination. ...

  12. Phonotaxis to advertisement calls by midwife toads (Alytes muletensis) is not necessarily related to mating

    OpenAIRE

    Lea, Jerry; Dyson, Mandy; Halliday, Timothy

    2002-01-01

    Previous studies with the Mallorcan midwife toad (Alytes muletensis) found that gravid females show inconsistent phonotactic preferences for male calls unless they are highly motivated to mate; and, non-gravid females will occasionally show phonotaxis to male advertisement calls. These results suggest that sometimes phonotaxis may not be related to seeking a mating partner. In this article we report on experiments that give further support to a non-mating function of phonotaxis in this specie...

  13. Storage and recovery of elastic potential energy powers ballistic prey capture in toads.

    Science.gov (United States)

    Lappin, A Kristopher; Monroy, Jenna A; Pilarski, Jason Q; Zepnewski, Eric D; Pierotti, David J; Nishikawa, Kiisa C

    2006-07-01

    Ballistic tongue projection in toads is a remarkably fast and powerful movement. The goals of this study were to: (1) quantify in vivo power output and activity of the depressor mandibulae muscles that are responsible for ballistic mouth opening, which powers tongue projection; (2) quantify the elastic properties of the depressor mandibulae muscles and their series connective tissues using in situ muscle stimulation and force-lever studies; and (3) develop and test an elastic recoil model, based on the observed elastic properties of the depressor mandibulae muscles and series connective tissues, that accounts for displacement, velocity, acceleration and power output during ballistic mouth opening in toads. The results demonstrate that the depressor mandibulae muscles of toads are active for up to 250 ms prior to mouth opening. During this time, strains of up to 21.4% muscle resting length (ML) develop in the muscles and series connective tissues. At maximum isometric force, series connective tissues develop strains up to 14% ML, and the muscle itself develops strains up to 17.5% ML. When the mouth opens rapidly, the peak instantaneous power output of the depressor mandibulae muscles and series connective tissues can reach 9600 W kg(-1). The results suggest that: (1) elastic recoil of muscle itself can contribute significantly to the power of ballistic movements; (2) strain in series elastic elements of the depressor mandibulae muscle is too large to be borne entirely by the cross bridges and the actin-myosin filament lattice; and (3) central nervous control of ballistic tongue projection in toads likely requires the specification of relatively few parameters.

  14. Axial gradients of rhodopsin in light-exposed retinal rods of the toad

    OpenAIRE

    1990-01-01

    Exposure of an intact vertebrate eye to light bleaches the rhodopsin in the photoreceptor outer segments in spatially nonuniform patterns. Some axial bleaching patterns produced in toad rods were determined using microspectrophotometric techniques. More rhodopsin was bleached at the base of the outer segment than at the distal tip. The shape of the bleaching gradient varied with the extent of bleach and with the spectral content of the illuminant. Monochromatic light at the lambda max of the ...

  15. Rapid differentiation of sexual signals in invasive toads: call variation among populations

    OpenAIRE

    Kiyomi Yasumiba; Duffy, Richard L.; Parsons, Scott A.; Ross A Alford; Lin Schwarzkopf

    2016-01-01

    Advertisement calls tend to differ among populations, based on morphological and environmental factors, or simply geographic distance, in many taxa. Invasive cane toads (Rhinella marina) were introduced to Australia in 1935 and their distribution has expanded at increasing rates over time. Rapid evolution occurred in morphological and behavioural characters that accelerate dispersal, but the effects of rapid expansion on sexual signals have not been examined. We collected advertisement calls ...

  16. Vasculature of the parotoid glands of four species of toads (bufonidae: bufo).

    Science.gov (United States)

    Hutchinson, Deborah A; Savitzky, Alan H

    2004-05-01

    The parotoid glands of toads (Bufonidae) consist of large aggregations of granular glands located between the otic region of the skull and the scapular region. To determine the circulatory pattern of these glands, we perfused the vascular systems of Bufo alvarius, B. marinus, B. terrestris, and B. valliceps with either India ink or Microfil, a fine latex. The perfused glands were studied by gross dissection, microscopic examination, and histology. The vascular patterns of the parotoid glands were compared to the arrangement of vessels in the dorsal skin of Rana sphenocephala (Ranidae), a frog that lacks parotoid glands. The parotoid glands of the four species of toads are supplied with blood by the lateral and dorsal cutaneous arteries and are drained by one or more branches of the internal jugular vein. The dorsal cutaneous artery supplies most of the blood to the parotoid glands in B. terrestris and B. valliceps. In B. alvarius and B. marinus, both the lateral and dorsal cutaneous arteries serve major roles in the blood supply of the glands. These patterns of blood flow have not been described previously for parotoid glands and conflict with earlier accounts for B. alvarius and B. marinus. The arteries and veins associated with the parotoid glands of toads are present in R. sphenocephala, but are arranged differently. In R. sphenocephala, the lateral cutaneous artery supplies the dorsal and lateral skin posterior to the shoulder region, whereas the dorsal cutaneous artery supplies the skin of the shoulder region. In toads, both the lateral and dorsal cutaneous arteries supply the skin of the shoulder region and ramify into subcutaneous capillaries that surround the secretory units of the parotoid glands. Extensive vasculature presumably is important for delivering cholesterol and other precursor molecules to the parotoid glands, where those compounds are converted into toxins.

  17. Deep genetic structure and ecological divergence in a widespread human commensal toad

    OpenAIRE

    Wogan, GOU; Stuart, BL; Iskandar, DT; McGuire, JA

    2016-01-01

    © 2016 The Author(s) Published by the Royal Society. All rights reserved. The Asian common toad (Duttaphrynus melanostictus) is a human commensal species that occupies a wide variety of habitats across tropical Southeast Asia. We test the hypothesis that genetic variation in D. melanostictus is weakly associated with geography owing to natural and human-mediated dispersal facilitated by its commensal nature. Phylogenetic and population genetic analyses of mitochondrial and nuclear DNA sequenc...

  18. About a Snail, a Toad, and Rodents: Animal Models for Adaptation Research

    OpenAIRE

    Roubos, Eric W.; Bruce G. Jenks; Lu eXu; Miyuki eKuribara; Wim J. J. M. Scheenen; Tamas eKozicz

    2010-01-01

    Neural adaptation mechanisms have many similarities throughout the animal kingdom, enabling to study fundamentals of human adaptation in selected animal models with experimental approaches that are impossible to apply in man. This will be illustrated by reviewing research on three of such animal models, viz. (1) the egg-laying behavior of a snail, Lymnaea stagnalis: how one neuron type controls behavior, (2) adaptation to the ambient light condition by a toad, Xenopus laevis: how a neuroendoc...

  19. Effects of weather on survival in populations of boreal toads in Colorado

    Science.gov (United States)

    Scherer, R. D.; Muths, E.; Lambert, B.A.

    2008-01-01

    Understanding the relationships between animal population demography and the abiotic and biotic elements of the environments in which they live is a central objective in population ecology. For example, correlations between weather variables and the probability of survival in populations of temperate zone amphibians may be broadly applicable to several species if such correlations can be validated for multiple situations. This study focuses on the probability of survival and evaluates hypotheses based on six weather variables in three populations of Boreal Toads (Bufo boreas) from central Colorado over eight years. In addition to suggesting a relationship between some weather variables and survival probability in Boreal Toad populations, this study uses robust methods and highlights the need for demographic estimates that are precise and have minimal bias. Capture-recapture methods were used to collect the data, and the Cormack-Jolly-Seber model in program MARK was used for analysis. The top models included minimum daily winter air temperature, and the sum of the model weights for these models was 0.956. Weaker support was found for the importance of snow depth and the amount of environmental moisture in winter in modeling survival probability. Minimum daily winter air temperature was positively correlated with the probability of survival in Boreal Toads at other sites in Colorado and has been identified as an important covariate in studies in other parts of the world. If air temperatures are an important component of survival for Boreal Toads or other amphibians, changes in climate may have profound impacts on populations. Copyright 2008 Society for the Study of Amphibians and Reptiles.

  20. Concentration dependence of halide fluxes and selectivity of the anion pathway in toad skin

    DEFF Research Database (Denmark)

    Harck, A F; Larsen, Erik Hviid

    1986-01-01

    The isolated toad (Bufo bufo) skin was mounted under voltage-clamp conditions in a chamber shown to cause no significant edge damage. The serosal side of the skin was bathed with NaCl-Ringer's, and the passive voltage-sensitive anion conductance studied in its fully voltage activated state, V = -...... of the red cell membrane accounts for our findings, and for an inwardly directed active Cl- flux in terms of Cl-/HCO3- exchange....

  1. First report on toxins in the Panamanian toads Atelopus limosus, A. glyphus and A. certus.

    Science.gov (United States)

    Yotsu-Yamashita, Mari; Tateki, Eiko

    2010-01-01

    Major toxins from skin extracts of 18 specimens of six Atelopus toad species collected in Panama were analyzed. Chiriquitoxin was identified using (1)H NMR in A. limosus and A. glyphus for the first time. Zetekitoxin in A. zeteki and tetrodotoxin in A. varius, A. chiriquiensis and A. zeteki were identified again. Furthermore, A. certus was suggested to contain a water-soluble toxin other than tetrodotoxin. PMID:19596024

  2. Antiplasmodial and Cytotoxic Activities of Toad Venoms from Southern Amazon, Brazil.

    Science.gov (United States)

    Banfi, Felipe Finger; Guedes, Karla de Sena; Andrighetti, Carla Regina; Aguiar, Ana Carolina; Debiasi, Bryan Wender; Noronha, Janaina da Costa; Rodrigues, Domingos de Jesus; Júnior, Gerardo Magela Vieira; Sanchez, Bruno Antonio Marinho

    2016-08-01

    The drug-resistance of malaria parasites is the main problem in the disease control. The huge Brazilian biodiversity promotes the search for new compounds, where the animal kingdom is proving to be a promising source of bioactive compounds. The main objective of this study was to evaluate the antiplasmodial and cytotoxic activity of the compounds obtained from the toad venoms of Brazilian Amazon. Toad venoms were collected from the secretion of Rhinella marina and Rhaebo guttatus in Mato Grosso State, Brazil. The powder was extracted at room temperature, yielding 2 extracts (RG and RM) and a substance ('1') identified as a bufadienolide, named telocinobufagin. Growth inhibition, intraerythrocytic development, and parasite morphology were evaluated in culture by microscopic observations of Giemsa-stained thin blood films. Cytotoxicity was determined against HepG2 and BGM cells by MTT and neutral red assays. The 2 extracts and the pure substance ('1') tested were active against chloroquine-resistant Plasmodium falciparum strain, demonstrating lower IC50 values. In cytotoxic tests, the 2 extracts and substance '1' showed pronounced lethal effects on chloroquine-resistant P. faciparum strain and low cytotoxic effect, highlighting toad parotoid gland secretions as a promising source of novel lead antiplasmodial compounds. PMID:27658592

  3. Hydrosmotic effect of angiotensin II in the toad skin: role of cyclic AMP.

    Science.gov (United States)

    Coviello, A; Brauckmann, E S; de Atenor, M S; Apud, J A; Causarano, J

    1975-01-01

    The mechanism of action of the hydrosmotic response of the isolated skin of the toad Bufo arenarum Hensel to angiotensin II was studied by means of an indirect pharmacological approach. Angiotensin II (2.10(-10) M), vasopressin (2.10(-13) M) and theophylline (10(-4) and 10(-3) M) in subliminal doses produced a significant increase on water permeability when added in different paired combinations. Angiotensin II (2.10(-7) M) and vasopressin (2.10(-8) M) in doses producing significant effects on water permeability increased the response to submaximal doses of epinephrine (10(-6) M) but not to higher doses (10(-5) M). Acid pH (6.4) and prostaglandin E1 (2.10(-7) M) reduced significantly the hydrosmotic response to angiotensin II, but in contrast with the toad bladder, the effect was not completely abolished. Present results support the view that the hydrosmotic effect of angiotensin II in toad skin is mediated by the adenylate cyclase - cyclic AMP system. PMID:189568

  4. Efficacy of fenbendazole and levamisole treatments in captive Houston toads (Bufo [Anaxyrus] houstonensis).

    Science.gov (United States)

    Bianchi, Catherine M; Johnson, Cassidy B; Howard, Lauren L; Crump, Paul

    2014-09-01

    Effective disease monitoring and prevention is critical to the success of captive amphibian care. Nematodes, including the genera Rhabdias and Strongyloides, are known to contribute to mortality in captive amphibians and have been identified in the Houston Zoo's endangered Houston toad (Bufo [Anaxyrus] houstonensis) captive assurance colony. Five years of fecal data for the toad colony were compiled and analyzed in order to investigate the efficacy of two anthelminthic medications, fenbendazole (FBZ) and levamisole (LMS), which were used to control nematode infections. Both FBZ (dusted onto food items) and topical LMS (6.5 to 13.5 mg/kg) significantly reduced the number of nematode eggs, larvae, and adults observed by fecal parasitologic examination. There were no significant differences between treatments, and egg reappearance periods were difficult to compare as a result of low sample size. No adverse effects from either anthelminthic treatment were observed. Both topical LMS and oral FBZ appear to be safe and efficacious treatments for the reduction of the internal nematode burden in captive Houston toads.

  5. The osmotic behaviour of toad skin epithelium (Bufo viridis). an electron microprobe analysis.

    Science.gov (United States)

    Rick, R; Dörge, A; Katz, U; Bauer, R; Thurau, K

    1980-05-01

    The effect of saline adaptation on the intracellular Na, K, Cl, P concentrations and dry weight content of the toad skin epithelium (Bufo viridis) was studied using the technique of electron microprobe analysis. The measurements were performed on isolated abdominal skins either directly after dissection or after additional incubation in Ussing-type chambers. Adaptations of the toads to increasing NaCl concentrations for 7 days resulted in increased blood plasma osmolarity and a parallel increase in the cellular electrolyte, P and dry weight concentrations of the epithelium, the K increase representing the most significant fraction of the intracellular osmolarity increase. No evidence was obtained to show that the nucleus and cytoplasm reacted differently from each other and all living epithelial cell types basically showed the same response. Incubation of the isolated skins under control conditions showed a drastic inhibition of the transepithelial Na transport after adaptation to high salinities. In spite of the large variations in the transport rate almost identical intracellular electrolyte concentrations were observed. In tap water adapted toads the average cellular concentrations were 8.8 mmole/kg wet weight for Na, 109.6 for K, 41.5 for Cl, and 135.3 for P, respectively. Incubation of the skin with Ringer's solution of different osmolarities demonstrated that the epithelial cells are in osmotic equilibrium with the inner bathing solution. The results are consistent with the view that the osmotic adaptation is mainly accomplished by the movement of water. PMID:7191092

  6. Behavioral response and kinetics of terrestrial atrazine exposure in American toads (bufo americanus)

    Science.gov (United States)

    Storrs, Mendez S.I.; Tillitt, D.E.; Rittenhouse, T.A.G.; Semlitsch, R.D.

    2009-01-01

    Amphibians in terrestrial environments obtain water through a highly vascularized pelvic patch of skin. Chemicals can also be exchanged across this patch. Atrazine (ATZ), a widespread herbicide, continues to be a concern among amphibian ecologists based on potential exposure and toxicity. Few studies have examined its impact on the terrestrial juvenile or adult stages of toads. In the current study, we asked the following questions: (1) Will juvenile American toads (Bufo americanus) avoid soils contaminated with ATZ? (2) Can they absorb ATZ across the pelvic patch? (3) If so, how is it distributed among the organs and eventually eliminated? We conducted a behavioral choice test between control soil and soil dosed with ecologically relevant concentrations of ATZ. In addition, we examined the uptake, distribution, and elimination of water dosed with 14C-labeled ATZ. Our data demonstrate that toads do not avoid ATZ-laden soils. ATZ crossed the pelvic patch rapidly and reached an apparent equilibrium within 5 h. The majority of the radiolabeled ATZ ended up in the intestines, whereas the greatest concentrations were observed in the gall bladder. Thus, exposure of adult life stages of amphibians through direct uptake of ATZ from soils and runoff water should be considered in risk evaluations. ?? 2009 Springer Science+Business Media, LLC.

  7. Antiplasmodial and Cytotoxic Activities of Toad Venoms from Southern Amazon, Brazil

    Science.gov (United States)

    Banfi, Felipe Finger; Guedes, Karla de Sena; Andrighetti, Carla Regina; Aguiar, Ana Carolina; Debiasi, Bryan Wender; Noronha, Janaina da Costa; Rodrigues, Domingos de Jesus; Júnior, Gerardo Magela Vieira; Sanchez, Bruno Antonio Marinho

    2016-01-01

    The drug-resistance of malaria parasites is the main problem in the disease control. The huge Brazilian biodiversity promotes the search for new compounds, where the animal kingdom is proving to be a promising source of bioactive compounds. The main objective of this study was to evaluate the antiplasmodial and cytotoxic activity of the compounds obtained from the toad venoms of Brazilian Amazon. Toad venoms were collected from the secretion of Rhinella marina and Rhaebo guttatus in Mato Grosso State, Brazil. The powder was extracted at room temperature, yielding 2 extracts (RG and RM) and a substance (‘1’) identified as a bufadienolide, named telocinobufagin. Growth inhibition, intraerythrocytic development, and parasite morphology were evaluated in culture by microscopic observations of Giemsa-stained thin blood films. Cytotoxicity was determined against HepG2 and BGM cells by MTT and neutral red assays. The 2 extracts and the pure substance (‘1’) tested were active against chloroquine-resistant Plasmodium falciparum strain, demonstrating lower IC50 values. In cytotoxic tests, the 2 extracts and substance ‘1’ showed pronounced lethal effects on chloroquine-resistant P. faciparum strain and low cytotoxic effect, highlighting toad parotoid gland secretions as a promising source of novel lead antiplasmodial compounds. PMID:27658592

  8. A new gravimetric reference station in South America: The installation of the Superconducting Gravimeters SG038 at the Argentinian-German Geodetic Observatory AGGO

    Science.gov (United States)

    Wziontek, Hartmut; Nowak, Ilona; Hase, Hayo; Häfner, Michael; Güntner, Andreas; Reich, Marvin; Brunini, Claudio

    2016-04-01

    In April 2015, the Transportable Integrated Geodetic Observatory (TIGO) of BKG was moved from Concepcion / Chile to La Plata / Argentina and was inaugurated in July 2015 as the Argentinian-German Geodetic Observatory (AGGO). In December 2015 the superconducting gravimeter SG038 was set up. The new station is equipped with four stable pillars to serve as a reference station and comparison site for absolute gravimeters in the future. We report about the overland transportation of the SG with the sphere floating, its installation at the new site and the hydrological instrumentation to observe local water storage changes to model near field gravimetric effects. We give an outlook about the first months of gravity time series and assess the drift behaviour after transport.

  9. Total On-line Access Data System (TOADS): Phase II Final Report for the Period August 2002 - August 2004

    Energy Technology Data Exchange (ETDEWEB)

    Yuracko, K. L. [YAHSGS LLC, Richland, WA (United States); Parang, M. [YAHSGS LLC, Richland, WA (United States); Landguth, D. C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Coleman, R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2004-09-13

    TOADS (Total On-line Access Data System) is a new generation of real-time monitoring and information management system developed to support unattended environmental monitoring and long-term stewardship of U.S. Department of Energy facilities and sites. TOADS enables project managers, regulators, and stakeholders to view environmental monitoring information in realtime over the Internet. Deployment of TOADS at government facilities and sites will reduce the cost of monitoring while increasing confidence and trust in cleanup and long term stewardship activities. TOADS: Reliably interfaces with and acquires data from a wide variety of external databases, remote systems, and sensors such as contaminant monitors, area monitors, atmospheric condition monitors, visual surveillance systems, intrusion devices, motion detectors, fire/heat detection devices, and gas/vapor detectors; Provides notification and triggers alarms as appropriate; Performs QA/QC on data inputs and logs the status of instruments/devices; Provides a fully functional data management system capable of storing, analyzing, and reporting on data; Provides an easy-to-use Internet-based user interface that provides visualization of the site, data, and events; and Enables the community to monitor local environmental conditions in real time. During this Phase II STTR project, TOADS has been developed and successfully deployed for unattended facility, environmental, and radiological monitoring at a Department of Energy facility.

  10. Living up to its name? The effect of salinity on development, growth, and phenotype of the "marine" toad (Rhinella marina).

    Science.gov (United States)

    Wijethunga, Uditha; Greenlees, Matthew; Shine, Richard

    2016-02-01

    The highly permeable integument of amphibians renders them vulnerable to chemical characteristics of their environment, especially during the aquatic larval stage. As the cane toad (Rhinella marina, Bufonidae) invades southwards along the east coast of Australia, it is encountering waterbodies with highly variable conditions of temperature, pH, and salinity. Understanding the tolerance of toads to these conditions can clarify the likely further spread of the invader, as well as the adaptability of the species to novel environmental challenges. We measured salinity in waterbodies in the field and conducted laboratory trials to investigate the impacts of salinity on toad viability. Eggs and tadpoles from the southern invasion front tolerated the most saline conditions we found in potential spawning ponds during surveys [equivalent to 1200 ppm (3.5 % the salinity of seawater)]. Indeed, high-salinity treatments increased tadpole body sizes, accelerated metamorphosis, and improved locomotor ability of metamorphs (but did not affect metamorph morphology). At very low salinity [40 ppm (0.1 % seawater)], eggs hatched but larvae did not develop past Gosner stage 37. Our study shows that the egg and larval life stages of cane toads can tolerate wide variation in the salinity of natal ponds and that this aspect of waterbody chemistry is likely to facilitate rather than constrain continued southward expansion of the toad invasion front in eastern Australia. PMID:26553545

  11. Argentinian president Cristina de Kirchner starts commissioning of Atucha II mechanical systems; Inbetriebsetzung der Maschinentechnik in Atucha II durch die Staatspraesidenten Argentiniens

    Energy Technology Data Exchange (ETDEWEB)

    Fabian, Hermann O. [NA-SA-Beratungskomitee zu Designfragen, Erlangen (Germany); Mazzantini, Oscar A. [Nuclearelectrica Argentina SA, Atucha (Argentina). Licensing and Safety

    2012-01-15

    On September 28, 2011, construction of the Atucha II heavy-water reactor plant (CNA II, 745 gross MWe) in Argentina reached another important milestone on its way to completion of the project. In the presence of Argentinian State President Cristina Fernandez de Kirchner, commissioning of the mechanical systems was initiated. The technology of the Atucha reactor facilities, which are fueled with natural uranium, moderated by heavy water (D{sub 2}O) and cooled by light water (H{sub 2}O) (Pressurized Heavy Water Reactor, PHWR), originally was developed by Siemens. These plants were designed alongside the pressurized water reactors using light water. The strict requirements applying to advanced designs in Germany as well as current findings in technical implementation were employed. Major construction and mechanical assembly work has been completed. The primary system has been installed completely. The first core was manufactured at the Argentinian fuel element factory of Conuar and placed into the plant's dry store, which also contains the control and shutdown rods. The heavy water (D{sub 2}O) needed for nuclear operation has been produced and is being stored on the plant premises. Extensive commissioning work is going on in the building for the switching systems including the main and the emergency control rooms. The turbine hall is largely complete, as are the facilities for cooling water supply. The commissioning phase of the plant has been started involving considerable manpower. Some procedures for the later part of the commissioning phase still need to be completed. As a consequence of its sound and qualified basic design and the incorporation of other, new findings, Atucha II in its optimized design will prove to be a safe and reliable plant in operation. The start of commercial operation of Atucha II has been announced for probably late 2012. (orig.)

  12. Foraging modality and plasticity in foraging traits determine the strength of competitive interactions among carnivorous plants, spiders and toads.

    Science.gov (United States)

    Jennings, David E; Krupa, James J; Rohr, Jason R

    2016-07-01

    Foraging modalities (e.g. passive, sit-and-wait, active) and traits are plastic in some species, but the extent to which this plasticity affects interspecific competition remains unclear. Using a long-term laboratory mesocosm experiment, we quantified competition strength and the plasticity of foraging traits in a guild of generalist predators of arthropods with a range of foraging modalities. Each mesocosm contained eight passively foraging pink sundews, and we employed an experimental design where treatments were the presence or absence of a sit-and-wait foraging spider and actively foraging toad crossed with five levels of prey abundance. We hypothesized that actively foraging toads would outcompete the other species at low prey abundance, but that spiders and sundews would exhibit plasticity in foraging traits to compensate for strong competition when prey were limited. Results generally supported our hypotheses. Toads had a greater effect on sundews at low prey abundances, and toad presence caused spiders to locate webs higher above the ground. Additionally, the closer large spider webs were to the ground, the greater the trichome densities produced by sundews. Also, spider webs were larger with than without toads and as sundew numbers increased, and these effects were more prominent as resources became limited. Finally, spiders negatively affected toad growth only at low prey abundance. These findings highlight the long-term importance of foraging modality and plasticity of foraging traits in determining the strength of competition within and across taxonomic kingdoms. Future research should assess whether plasticity in foraging traits helps to maintain coexistence within this guild and whether foraging modality can be used as a trait to reliably predict the strength of competitive interactions. PMID:27061175

  13. Geology and mammalian paleontology of the Horned Toad Hills, Mojave Desert, California, USA

    Science.gov (United States)

    May, S.R.; Woodburne, M.O.; Lindsay, E.H.; Albright, L.B.; Sarna-Wojcicki, A.; Wan, E.; Wahl, D.B.

    2011-01-01

    The Horned Toad Formation includes five lithostratigraphic members that record alluvial fan, fluvial, lake margin, and lacustrine deposition within a relatively small basin just south of the active Garlock fault during the late Miocene to early Pliocene. These sediments experienced northwest-southeast contractional deformation during the Pliocene-Pleistocene associated with basement-involved reverse faults. Member Two of the Horned Toad Formation has yielded 24 taxa of fossil mammals, referred to as the Warren Local Fauna, including Cryptotis sp., cf. Scapanus, Hypolagus vetus, Hypolagus edensis,? Spermophilus sp., Prothomomys warrenensis n. gen., n. sp., Perognathus sp., Repomys gustelyi, Postcopemys valensis, Peromyscus sp. A, Peromyscus sp. B, Jacobsomys dailyi n. sp., Borophagus cf. B. secundus, cf. Agriotherium, Machairodus sp. cf. M. coloradensis, Rhynchotherium sp. cf. R. edensis, Pliomastodon vexillarius, Dinohippus edensis, Teleoceras sp. cf. T. fossiger, cf. Prosthennops, Megatylopus sp. cf. M. matthewi, Hemiauchenia vera, Camelidae gen. et. sp. indet., and the antilocaprid cf. Sphenophalos. The majority of fossil localities are confined to a 20 m thick stratigraphic interval within a reversed polarity magnetozone. The fauna demonstrates affinity with other late Hemphillian faunas from California, Nevada, Nebraska, Texas, and Mexico. The Lawlor Tuff, dated elsewhere in California at 4.83 ?? 0.04 Ma and geochemically identified in the Horned Toad Formation, overlies most of the fossil mammal localities. Magnetic polarity data are correlated with Chrons 3n.3r, 3n.3n, and 3n.2r, suggesting an age of approximately 5.0 - 4.6 Ma. These constraints indicate an age for the late Hemphillian Warren Local Fauna of 4.85 - 5.0 Ma. ?? Society of Vertebrate Paleontology November 2011.

  14. Assessment of virally vectored autoimmunity as a biocontrol strategy for cane toads.

    Directory of Open Access Journals (Sweden)

    Jackie A Pallister

    Full Text Available BACKGROUND: The cane toad, Bufo (Chaunus marinus, is one of the most notorious vertebrate pests introduced into Australia over the last 200 years and, so far, efforts to identify a naturally occurring B. marinus-specific pathogen for use as a biological control agent have been unsuccessful. We explored an alternative approach that entailed genetically modifying a pathogen with broad host specificity so that it no longer caused disease, but carried a gene to disrupt the cane toad life cycle in a species specific manner. METHODOLOGY/PRINCIPAL FINDINGS: The adult beta globin gene was selected as the model gene for proof of concept of autoimmunity as a biocontrol method for cane toads. A previous report showed injection of bullfrog tadpoles with adult beta globin resulted in an alteration in the form of beta globin expressed in metamorphs as well as reduced survival. In B. marinus we established for the first time that the switch from tadpole to adult globin exists. The effect of injecting B. marinus tadpoles with purified recombinant adult globin protein was then assessed using behavioural (swim speed in tadpoles and jump length in metamorphs, developmental (time to metamorphosis, weight and length at various developmental stages, protein profile of adult globin and genetic (adult globin mRNA levels measures. However, we were unable to detect any differences between treated and control animals. Further, globin delivery using Bohle iridovirus, an Australian ranavirus isolate belonging to the Iridovirus family, did not reduce the survival of metamorphs or alter the form of beta globin expressed in metamorphs. CONCLUSIONS/SIGNIFICANCE: While we were able to show for the first time that the switch from tadpole to adult globin does occur in B. marinus, we were not able to induce autoimmunity and disrupt metamorphosis. The short development time of B. marinus tadpoles may preclude this approach.

  15. Inducement of Sechenov inhibition by EtOH and NA in the Bufo toad

    Institute of Scientific and Technical Information of China (English)

    LI RuXin; JIA ShanShan; LI YingZi; CAO Yin; CHENG XiuZhen; XIE ZuoPing

    2008-01-01

    Central inhibition, discovered by Sechenov in 1862, suggests that electrically stimulating the forebrain or medulla oblongata in frog generally suppresses reflexes. However, the underlying molecular mechanisms are still unclear. Using ethanol (EtOH), noradrenalin (NA), and other neurotransmitters in thalamic preparations, Sechenov inhibition was stimulated in Bufo toads in this study. The result showed that, similar to Sechenov inhibition, the acute application of EtOH or NA excited the thalamus and prolonged the latency of withdrawal reflex. Our study evidences the involvement of α-adrenoceptors in such central inhibition, and explains the role of acute EtOH application in the in-duction of reflex inhibition.

  16. Aversive and non-reward learning in the fire-bellied toad using familiar and unfamiliar prey stimuli

    Institute of Scientific and Technical Information of China (English)

    Ursula DICKE; Antje HEIDORN; Gerhard ROTH

    2011-01-01

    The present study investigated how snapping behavior toward familiar and unfamiliar prey is modified by reward omission and aversive conditioning in the fure-bellied toad Bombina orientalis.Toads were trained to snap at cricket images by rewarding them with live crickets.The task was learned,and the learning criterion (10 snapping responses within 2 minutes) was reached in all individuals investigated.Subsequent reward omission did not alter the frequency of snapping to the familiar cricket stimulus.Snapping decreased only in some individuals,when a mild foot shock was applied at snapping.However,at presentation of images of hitherto unfamiliar meal worms and foot-shock application at snapping to the stimulus,the majority of toads diminished snapping significantly.Snapping responses decreased more rapidly,when snapping at meal worms was not rewarded or a footshock was applied uncorrelated to the presentation of or snapping at meal worms.These results demonstrate that in toads familiarity and unfamiliarity of prey stimuli are important factors in aversive learning,because well-trained responses to familiar stimuli become immune against reward omission.Furthermore,at presentation of unfamiliar stimuli,omission of reward and uncorrelated footshock had a stronger aversive effect than correlated footshock [Current Zoology 57 (6):709-716,2011 ].

  17. 77 FR 6815 - Emergency Exemption; Issuance of Emergency Permit To Salvage Houston Toads Affected by a Wildfire...

    Science.gov (United States)

    2012-02-09

    ... for public inspection, by appointment only, during normal business hours at the U.S. Fish and Wildlife... the FEMA clean-up. Efforts to salvage adults, juveniles, tadpoles, or egg masses are currently taking... toads may include the following activities: collect as adults, juveniles, tadpoles, or eggs from...

  18. Post-breeding habitat use by adult Boreal Toads (Bufo boreas) after wildfire in Glacier National Park, USA

    Science.gov (United States)

    Guscio, C.G.; Hossack, B.R.; Eby, L.A.; Corn, P.S.

    2008-01-01

    Effects of wildfire on amphibians are complex, and some species may benefit from the severe disturbance of stand-replacing fire. Boreal Toads (Bufo boreas boreas) in Glacier National Park, Montana, USA increased in occurrence after fires in 2001 and 2003. We used radio telemetry to track adult B. boreas in a mosaic of terrestrial habitats with different burn severities to better understand factors related to the post-fire pulse in breeding activity. Toads used severely burned habitats more than expected and partially burned habitats less than expected. No toads were relocated in unburned habitat, but little of the study area was unburned and the expected number of observations in unburned habitat was < 3. High vagility of B. boreas and preference for open habitats may predispose this species to exploit recently disturbed landscapes. The long-term consequences of fire suppression likely have had different effects in different parts of the range of B. boreas. More information is needed, particularly in the northern Rocky Mountains, where toads are more likely to occupy habitats that have diverged from historic fire return intervals. Copyright ?? 2008. C. Gregory Guscio. All rights reserved.

  19. Alfaxalone-butorphanol versus alfaxalone-morphine combination for immersion anaesthesia in oriental fire-bellied toads (Bombina orientalis).

    Science.gov (United States)

    Adami, Chiara; d'Ovidio, Dario; Casoni, Daniela

    2016-06-01

    Oriental fire-bellied toads (Bombina orientalis) are small semi-aquatic anuran species popular as both pets and laboratory animals. Although they are commonly anaesthetized to undergo clinical and experimental procedures, very little is known about their anaesthetic management. The aims of this prospective, randomized, cross-over experimental trial were to establish effective butorphanol and morphine concentrations to be added to alfaxalone for immersion anaesthesia (pilot study), and to compare the anaesthetic and antinociceptive effects of the two drug mixtures (alfaxalone-butorphanol and alfaxalone-morphine), in Bombina orientalis toads. For the actual trial, the toads were randomly assigned to one of two treatment groups: AB and AM, with seven animals in each group, which received alfaxalone-butorphanol and alfaxalone-morphine combinations, respectively, at the concentrations established during the pilot study. Heart rate, respiratory rate, von Frey filament threshold and response to nociceptive withdrawal (NWR), righting and myotactic reflexes were measured at 5 min intervals until return of righting reflex was observed. The investigator who carried out all the measurements was blinded to the treatment. Any undesired effect or complication was noted and recorded. The two treatments were found to be comparable in terms of onset and duration of anaesthesia, and occurrence of undesired effects. However, group AM resulted in lower NWR scores and higher von Frey filament thresholds than group AB. It is concluded that, at the investigated concentrations and in combination with alfaxalone by immersion, morphine provides better antinociception than butorphanol in oriental fire-bellied toads.

  20. Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations.

    Energy Technology Data Exchange (ETDEWEB)

    Moseley, Kurtis R.; Steven B. Castleberry; James L. Hanula; Mark Ford.

    2005-04-01

    ABSTRACT In the southeastern United States, coarse woody debris (CWD) typically harbors high densities of invertebrates. However, its importance as a foraging substrate for southeastern amphibians is relatively unknown. We examined effects of CWD manipulations on diet composition of southern toads (Bufo terrestris) in upland loblolly pine (Pinus taeda) stands in the Coastal Plain of South Carolina. Twelve 9.3-ha plots were assigned one of the following treatments: removal- all CWD _10 cm in diameter and _60 cm long removed; downed- five-fold increase in volume of down CWD; and unmanipulated control stands. We collected southern toads _4 cm snout-vent length (SVL) during 14 d sampling periods in June and October 2002, June 2003 and during a 28 d sampling period in April 2003. We collected 80, 36 and 35 southern toads in control, downed and removal treatments, respectively. We found no difference in relative abundance or frequency of invertebrate groups consumed among treatments (P.0.05). Average body weight (g), SVL (cm) and stomach content weight (g wet) of individuals also were similar among treatments (P . 0.05). The role of CWD as a foraging substrate for southern toads in loblolly pine stands of the southeastern Coastal Plain may be negligible, at least in the early stages of decay.

  1. Modification of a prey catching response and the development of behavioral persistence in the fire-bellied toad (Bombina orientalis).

    Science.gov (United States)

    Ramsay, Zachary J; Ikura, Juntaro; Laberge, Frédéric

    2013-11-01

    The present report investigated how fire-bellied toads (Bombina orientalis) modified their response in a prey catching task in which the attribution of food reward was contingent on snapping toward a visual stimulus of moving prey displayed on a computer screen. Two experiments investigated modification of the snapping response, with different intervals between the opportunity to snap at the visual stimulus and reward administration. The snapping response of unpaired controls was decreased compared with the conditioned toads when hour or day intervals were used, but intervals of 5 min produced only minimal change in snapping. The determinants of extinction of the response toward the visual stimulus were then investigated in 3 experiments. The results of the first experiment suggested that increased resistance to extinction depended mostly on the number of training trials, not on partial reinforcement or the magnitude of reinforcement during training. This was confirmed in a second experiment showing that overtraining resulted in resistance to extinction, and that the pairing of the reward with a response toward the stimulus was necessary for that effect, as opposed to pairing reward solely with the experimental context. The last experiment showed that the time elapsed between training trials also influenced extinction, but only in toads that received few training trials. Overall, the results suggest that toads learning about a prey stimulus progress from an early flexible phase, when an action can be modified by its consequences, to an acquired habit characterized by an increasingly inflexible and automatic response.

  2. Behavioral and neural responses of toads to salt solutions correlate with basolateral membrane potential of epidermal cells of the skin

    DEFF Research Database (Denmark)

    Hillyard, Stanley D; Baula, Victor; Tuttle, Wendy;

    2007-01-01

    Dehydrated toads initiated water absorption response (WR) behavior and absorbed water from dilute NaCl solutions. With 200-250 mM NaCl, WR behavior and water absorption were both suppressed. With 200-250 mM Na-gluconate, WR initiation was significantly greater than with NaCl but water loss was gr...

  3. Larger body size at metamorphosis enhances survival, growth and performance of young cane toads (Rhinella marina.

    Directory of Open Access Journals (Sweden)

    Elisa Cabrera-Guzmán

    Full Text Available Body size at metamorphosis is a key trait in species (such as many anurans with biphasic life-histories. Experimental studies have shown that metamorph size is highly plastic, depending upon larval density and environmental conditions (e.g. temperature, food supply, water quality, chemical cues from conspecifics, predators and competitors. To test the hypothesis that this developmental plasticity is adaptive, or to determine if inducing plasticity can be used to control an invasive species, we need to know whether or not a metamorphosing anuran's body size influences its subsequent viability. For logistical reasons, there are few data on this topic under field conditions. We studied cane toads (Rhinella marina within their invasive Australian range. Metamorph body size is highly plastic in this species, and our laboratory studies showed that larger metamorphs had better locomotor performance (both on land and in the water, and were more adept at catching and consuming prey. In mark-recapture trials in outdoor enclosures, larger body size enhanced metamorph survival and growth rate under some seasonal conditions. Larger metamorphs maintained their size advantage over smaller siblings for at least a month. Our data support the critical but rarely-tested assumption that all else being equal, larger body size at metamorphosis is likely to enhance an individual's long term viability. Thus, manipulations to reduce body size at metamorphosis in cane toads may help to reduce the ecological impact of this invasive species.

  4. Diffusion of 133Xe through frog skins, toad bladders, and water boundary layers

    International Nuclear Information System (INIS)

    We have measured the total permeability coefficients P as a function of stirring frequency ω for 133Xe through frog skins and toad bladders. The permeability coefficients for the frog skins and toad bladders proper are, respectively, P/sub m/ = (3.9 +- 0.8) x 10-4 cm/s and (7.4 +- 4.2) x 10-4 cm/s. ''Unstirred'' water layer thickness delta is determined concurrently, from the frequency dependence of P(ω); the result for frog skin is delta = (0.060 +- 0.016)/√ω(rad/s) cm. The stirring frequency range is from ω = 7.5 rad/s (72 rpm) to 55 rad/s (530 rpm). The results support the conclusions that the principal barrier to Xe diffusion in these epithelia is inter- and intracellular water, and that the diffusion is passive and rapid. The experimental method may be straightforwardly adapted to the measurement of diffusion or counterdiffusion of any gamma-radioactive soluble or partly soluble solute through any flat membrane or through a solvent. We estimate the amount of total body-absorbed radioactivity due to environmental 133Xe to be 50 fCi for an ambient concentration of 2.6 pCi/m3 of air

  5. Association preference and mechanism of kin recognition in tadpoles of the toad Bufo melanostictus

    Indian Academy of Sciences (India)

    Lilly Margaret Eluvathingal; Bhagyashri A Shanbhag; Srinivas K Saidapur

    2009-09-01

    In experiments with specially designed choice tanks, tadpoles of Bufo melanostictus spend significantly greater amounts of time near kin than near non-kin. However, in the absence of kin members, they prefer to spend more time near non-kin rather than stay away in isolation in the opposite blank zone with no company. This implies that association of toad tadpoles with their kin is due to attraction rather than repulsion from non-kin. Experiments designed to elucidate the sensory basis of kin recognition showed that toad tadpoles recognize their kin based on chemical cues rather than visual cues. They can also discriminate between homospecific non-kin and heterospecific (Sphaerotheca breviceps) tadpoles since the tadpoles spent significantly greater amounts of time near the former than near the latter. These findings suggest that where kin members are unavailable, selection may have favoured living with non-kin so as to derive benefits from group living and that a phenotype-matching mechanism may operate for both kin and species discrimination in B. melanostictus.

  6. spatial distribution pattern of the steppe toad-headed lizard (phrynocephalus frontalis) and its influencing factors

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    spatial distribution patterns are associated with life history and behavioral adaptations of animals.for studying the spatial distribution pattern of the steppe toad-headed lizard (phrynocephalusfrontalis) and its influencing factors,we conducted experiments in hunshandake sandy land in inner mongolia,china in july 2009.by calculating the clustered indices,we found that the lizard was aggregately distributed when the sampling quadrat was smaller than 10 m × 10 m,and uniformly distributed when it was greater than 10 m × 10 m.the nearest neighbor rule showed a clustering distribution pattern for p frontalis and the distribution pattern was quadrat-sampling dependent.furthermore,the cluster was determined by environmental factors when the sampling quadrat was smaller than 20 m × 20 m,but it was determined by both environmental factors and characteristics of the lizard when it was larger than 20 m × 20 m.our results suggested that the steppe toad-headed lizards tended to aggregate into suitable habitat patches in desert areas.additionally,we discussed that the lizard aggregation could be potentially used as an indictor of movement of sand dunes.

  7. A novel ubiquitin carboxyl terminal hydrolase is involved in toad oocyte maturation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13suc1-agaroseaffinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accessionnumber: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% iden-tities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functionaldomains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit theprogesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant proteinp28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis,a classical catalytic reaction for ubiquitin carboxyl terminai hydrolases (UCHs). The results in this paperreveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in theprocess of progesterone-induced oocyte maturation possibly through an involvement in protein turnover anddegradation.

  8. Differences and Similarities among Parotoid Macrogland Secretions in South American Toads: A Preliminary Biochemical Delineation

    Directory of Open Access Journals (Sweden)

    Juliana Mozer Sciani

    2013-01-01

    Full Text Available Amphibians are known by cutaneous glands, spread over the skin, containing toxins (proteins, peptides, biogenic amines, steroidal bufadienolides, and alkaloids used as chemical defense against predators and microbial infection. Toads are characterized by the presence of parotoid macroglands. The common toads have lately been divided into two genera: Bufo (Europe, Asia, and Africa and Rhinella (South America. Basal Rhaebo genus is exclusively of Central America and Amazon region. Although Rhinella and Rhaebo are related, species may share differences due to the diversity of environments that they live in. In this work, we have performed a biochemical characterization of the components of the poison of eight Rhinella species and one Rhaebo by means of RP-HPLC with either UV or MS detection and by SDS-PAGE, in order to verify whether phylogenetic and biological differences, such as habitat, diet, and defensive strategies, between them may also be reflected in poison composition. Although some components were common among the secretions, we were able to identify exclusive molecules to some species. The fact that closely related animals living in different habitats secrete different molecules into the skin is an indication that biological features, and not only evolution, seem to directly influence the skin secretion composition.

  9. ELECTRON MICROSCOPY OF ABSORPTION OF TRACER MATERIALS BY TOAD URINARY BLADDER EPITHELIUM.

    Science.gov (United States)

    CHOI, J K

    1965-05-01

    The absorption of Thorotrast and saccharated iron oxide by the epithelium of the toad urinary bladder was studied by electron microscopy. Whether the toads were hydrated, dehydrated, or given Pitressin, no significant differences in transport of colloidal particles by epithelial cells were observed. This implies that these physiological factors had little effect on the transport of the tracer particles. Tracer particles were encountered in three types of epithelial cells which line the bladder lumen, but most frequently in the mitochondria-rich cells. Tracer materials were incorporated into the cytoplasm of epithelial cells after being adsorbed to the coating layer covering the luminal surface of the cells. In the intermediate stage (1 to 3 hours after introducing tracer) particles were present in small vesicles, tubules, and multivesicular bodies. In the later stages (up to 65 hours), the particles were more commonly seen to be densely packed within large membrane-bounded bodies which were often found near the Golgi region. These large bodies probably were formed by the fusion of small vesicles. Irrespective of the stages of absorption, no particles were found in the intercellular spaces or in the submucosa. Particles apparently did not penetrate the intercellular spaces of the epithelium beyond the level of the tight junction.

  10. Functional assessment of toad parotoid macroglands: a study based on poison replacement after mechanical compression.

    Science.gov (United States)

    Jared, Simone G S; Jared, Carlos; Egami, Mizue I; Mailho-Fontana, Pedro L; Rodrigues, Miguel T; Antoniazzi, Marta M

    2014-09-01

    Toads have a pair of parotoid macroglands behind the eyes that secrete poison used in passive defence against predators. These macroglands are composed of juxtaposed alveoli, each one bearing a syncytial gland, all connected to the exterior by ducts. When the parotoids are bitten, the poison is expelled on the predator oral mucosa in the form of jets, causing several pharmacological actions. After poison release, the empty secretory syncytia immediately collapse in the interior of their respective alveoli and gradually start refilling. After parotoid manual compression, simulating a predator's bite, we studied, by means of morphological methods, the replacement of the poison inside the alveoli. The results showed that after compression, a considerable number of alveoli remained intact. In the alveoli that were effectively affected the recovery occurs in different levels, from total to punctual and often restrict to some areas of the syncytia. The severely affected alveoli seem not recover their original functional state. The fact that only a part of the parotoid alveoli is compressed during an attack seems to be crucial for toad survival, since the amphibian, after being bitten by a predator, do not lose all its poison stock, remaining protected in case of new attacks. PMID:24911375

  11. CRED Optical Validation Data at the island of Ofu and Olosega in American Samoa, 2012 to support Benthic Habitat Mapping (TOAD)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Optical validation data were collected using the Tethered Optical Assessment Device (TOAD), a sled equipped with underwater video camera, still camera and lights....

  12. New regional record and notes on historical specimens of Gunther Toad Duttaphrynus hololius with comments on other southeastern Indian congeners

    OpenAIRE

    Srinivasulu, B.; S.R. Ganesh; C. Srinivasulu

    2013-01-01

    We report on the finding of the Günther Toad Duttaphrynus hololius from Visakhapatnam and discuss aspects of its distribution based on our species distribution modeling. We also provide data on historically collected specimens and refine its intra-specific variation, provide an up-to-date chresonymy and comment on the validity of earlier reported diagnosis. Lastly, we remark on some misidentification-mediated dubious southern Indian records of another, related congener, the Marbled Toad D. ...

  13. Peptide IC-20, encoded by skin kininogen-1 of the European yellow-bellied toad, Bombina variegata, antagonizes bradykinin-induced arterial smooth muscle relaxation

    OpenAIRE

    Mu Yang; Mei Zhou; Bing Bai; Chengbang Ma; Le Wei; Lei Wang; Tianbao Chen; Chris Shaw

    2011-01-01

    Objectives: The objectives were to determine if the skin secretion of the European yellow-bellied toad (Bombina variegata), in common with other related species, contains a bradykinin inhibitor peptide and to isolate and structurally characterize this peptide. Materials and Methods: Lyophilized skin secretion obtained from this toad was subjected to reverse phase HPLC fractionation with subsequent bioassay of fractions for antagonism of the bradykinin activity using an isolated rat tail arter...

  14. Habitat suitability of patch types:A case study of the Yosemite toad

    Institute of Scientific and Technical Information of China (English)

    Christina T.LIANG; Thomas J.STOHLGREN

    2011-01-01

    Understanding patch variability is crucial in understanding the spatial population structure of wildlife species,especially for rare or threatened species.We used a well-tested maximum entropy species distribution model (Maxent) to map the Yosemite toad (Anaxyrus (= Bufo) canorus) in the Sierra Nevada mountains of California.Twenty-six environmental variables were included in the model representing climate,topography,land cover type,and disturbance factors (e.g.,distances to agricultural lands,fire perimeters,and timber harvest areas) throughout the historic range of the toad.We then took a novel approach to the study of spatially structured populations by applying the species-environmental matching model separately for 49 consistently occupied sites of the Yosemite toad compared to 27 intermittently occupied sites.We found that the distribution of the entire population was highly predictable (AUC= 0.95±0.03 SD),and associated with low slopes,specific vegetation types (wet meadow,alpine-dwarf shrub,montane chaparral,red fir,and subalpine conifer),and warm temperatures.The consistently occupied sites were also associated with these same factors,and they were also highly predictable (AUC= 0.95±0.05 SD).However,the intermittently occupied sites were associated with distance to fire perimeter,a slightly different response to vegetation types,distance to timber harvests,and a much broader set of aspect classes (AUC = 0.90±0.11 SD).We conclude that many studies of species distributions may benefit by modeling spatially structured populations separately.Modeling and monitoring consistently-occupied sites may provide a realistic snapshot of current speciesenvironment relationships,important climatic and topographic patterns associated with species persistence patterns,and an understanding of the plasticity of the species to respond to varying climate regimes across its range.Meanwhile,modeling and monitoring of widely dispersing individuals and intermittently occupied

  15. EFFECT OF ANGELICA SINENSIS ON AFFERENT DISCHARGE OF SINGLE MUSCLE SPINDLE IN TOADS

    Institute of Scientific and Technical Information of China (English)

    高云芳; 樊小力

    2004-01-01

    Objective In drugs for invigorating blood circulation, to find a herb that can stimulate afferent discharge of muscle spindle. Methods A single muscle spindle was isolated from sartorial muscle of toad. Using air-gap technique, afferent discharge of the muscle spindle was recorded. Effects of Angelica Sinensis, Salvia Miltiorrhiza, and Safflower on afferent discharge of the muscle spindle were observed. Results Angelica Sinensis could distinctly increase afferent discharge frequency of the muscle spindle, and this increase was dose-dependent. But Salvia Miltiorrhiza and Safflower had no this excitatory effect. Conclusion It is known that Angelica Sinensis can invigorate blood circulation, and we have found its excitatory effect on muscle spindle which makes it possible to serve people with muscle atrophy if more evidences from clinical experiments are available.

  16. Cytological evidence for population-specific sex chromosome heteromorphism in Palaearctic green toads (Amphibia, Anura)

    Indian Academy of Sciences (India)

    G Odierna; G Aprea; T Capriglione; S Castellano; E Balletto

    2007-06-01

    A chromosome study was carried out on a number of European and Central Asiatic diploid green toad populations by means of standard and various other chromosome banding and staining methods (Ag-NOR-, Q-, CMA3-, late replicating [LR] banding pattern, C- and sequential C-banding + CMA3 + DAPI). This study revealed the remarkable karyological uniformity of specimens from all populations, with the only exception being specimens from a Moldavian population, where one chromosome pair was heteromorphic. Though similar in shape, size and with an identical heterochromatin distribution, the difference in the heteromorphic pair was due to a large inverted segment on its long arms. This heteromorphism was restricted to females, suggesting a female heterogametic sex chromosome system of ZZ/ZW type at a very early step of differentiation.

  17. KARYOTYPIC STUDY OF THE COMMON INDIAN TOAD, DUTTAPHRYNUS MELANOSTICTUS, FROM JAMMU AND KASHMIR, INDIA

    Directory of Open Access Journals (Sweden)

    Neelam Saba

    2014-01-01

    Full Text Available Karyotypic study of two sexes of the toad species, Duttaphrynus melanostictus, was carried out using giemsa staining, C- banding and NOR banding methods, from Jammu and Kashmir, India. The basic chromosome number was found to be 2n=22, fundamental arm number (NF was 44 with all the biarmed chromosomes and no sex chromosome heteromorphism was found. Cbanding and NOR banding was also performed. Paracentric C-band was on the long arm of first homologous pair. Centromeric heterochromatin appeared as darkly stained C-bands on all the chromosomes of diploid complement, whereas Ag-NOR staining showed a pair of nucleolar organizer regions present on pair no. 7 on short arm i.e. 7p in both male and female karyotypes.

  18. Rapid differentiation of sexual signals in invasive toads: call variation among populations.

    Science.gov (United States)

    Yasumiba, Kiyomi; Duffy, Richard L; Parsons, Scott A; Alford, Ross A; Schwarzkopf, Lin

    2016-01-01

    Advertisement calls tend to differ among populations, based on morphological and environmental factors, or simply geographic distance, in many taxa. Invasive cane toads (Rhinella marina) were introduced to Australia in 1935 and their distribution has expanded at increasing rates over time. Rapid evolution occurred in morphological and behavioural characters that accelerate dispersal, but the effects of rapid expansion on sexual signals have not been examined. We collected advertisement calls from four populations of different ages since invasion, and analysed the geographic differentiation of seven call parameters. Our comparisons indicate that the calls of R. marina differ among Australian populations. The signal variation was not simply clinal with respect to population age, climate, or morphological differentiation. We suggest that selection on signalling among populations has been idiosyncratic and may reflect local female preferences or adaptation to environmental factors that are not clinal such as energy availability. PMID:27328666

  19. Telencephalic neural activation following passive avoidance learning in a terrestrial toad.

    Science.gov (United States)

    Puddington, Martín M; Daneri, M Florencia; Papini, Mauricio R; Muzio, Rubén N

    2016-12-15

    The present study explores passive avoidance learning and its neural basis in toads (Rhinella arenarum). In Experiment 1, two groups of toads learned to move from a lighted compartment into a dark compartment. After responding, animals in the experimental condition were exposed to an 800-mM strongly hypertonic NaCl solution that leads to weight loss. Control animals received exposure to a 300-mM slightly hypertonic NaCl solution that leads to neither weight gain nor loss. After 10 daily acquisition trials, animals in the experimental group showed significantly longer latency to enter the dark compartment. Additionally, 10 daily trials in which both groups received the 300-mM NaCl solution after responding eliminated this group effect. Thus, experimental animals showed gradual acquisition and extinction of a passive avoidance respond. Experiment 2 replicated the gradual acquisition effect, but, after the last trial, animals were sacrificed and neural activation was assessed in five brain regions using AgNOR staining for nucleoli-an index of brain activity. Higher activation in the experimental animals, relative to controls, was observed in the amygdala and striatum. Group differences in two other regions, lateral pallium and septum, were borderline, but nonsignificant, whereas group differences in the medial pallium were nonsignificant. These preliminary results suggest that a striatal-amygdala activation could be a key component of the brain circuit controlling passive avoidance learning in amphibians. The results are discussed in relation to the results of analogous experiments with other vertebrates. PMID:27498147

  20. Landscape associations of frog and toad species in Iowa and Wisconsin, U.S.A

    Science.gov (United States)

    Knutson, M.G.; Sauer, J.R.; Olsen, D.A.; Mossman, M.J.; Hemesath, L.M.; Lannoo, M.J.; Kaiser, Hinrich; Casper, Gary S.; Bernstein, Neil P.

    2000-01-01

    Landscape habitat associations of frogs and toads in Iowa and Wisconsin were tested to determine whether they support or refute previous general habitat classifications. We examined which Midwestern species shared similar habitats to see if these associations were consistent across large geographic areas (states). Rana sylvatica (wood frog), Hyla versicolor (eastern gray treefrog), Pseudacris crucifer (spring peeper), and Acris crepitans (cricket frog) were identified as forest species, P. triseriata (chorus frog), H. chrysoscelis (Cope's gray treefrog), R. pipiens (leopard frog), and Bufo americanus (American toad) as grassland species, and R. catesbeiana (bullfrog), R. clamitans (green frog), R. palustris (pickerel frog), and R. septentrionalis (mink frog) as lake or stream species. The best candidates to serve as bioindicators of habitat quality were the forest species R. sylvatica, H. versicolor, and P. crucifer, the grassland species R. pipiens and P. triseriata, and a cold water wetland species, R. palustris. Declines of P. crucifer, R. pipiens, and R. palustris populations in one or both states may reflect changes in habitat quality. Habitat and community associations of some species differed between states, indicating that these relationships may change across the range of a species. Acris crepitans may have shifted its habitat affinities from open habitats, recorded historically, to the more forested habitat associations we recorded. We suggest contaminants deserve more investigation regarding the abrupt and widespread declines of this species. Interspersion of different habitat types was positively associated with several species. A larger number of wetland patches may increase breeding opportunities and increase the probability of at least one site being suitable. We noted consistently negative associations between anuran species and urban development. Given the current trend of urban growth and increasing density of the human population, declines of

  1. Nux Vomica 200 CH reduced acute hypnotic effect of alcohol in young toads

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    Nirmal Sukul

    2012-09-01

    Full Text Available Potentized Nux Vomica has been reported to produce antialcoholic effect in mice, rats and toads. The effect relates to consumption of alcohol and alcohol-induced loss of righting reflex (RR. RR’s maintain normal erect posture of an animal and are centrally controlled in the midbrain. In the present study young toads, Duttaphrynus melanostictus were first treated with Nux vomica 200 CH and then partially immersed in 209 mM ethanol solution in such a way that their head remained above the level of ethanol solution. Toadlets were removed from the ethanol solution every 10 min, tested for the loss of RR and returned to the ethanol solution. Toadlets were placed in a supine position on a dry flat surface. Failure to right within 60 sec was considered as the loss of RR. The experiment was repeated 10 times. Control toadlets were pretreated with 90% ethanol instead of Nux Vomica 200 CH. The percentages of toadlets showing loss of RR, both in the control as well as in the Nux-treated groups, were shown in graphs against the duration of exposure to ethanol solution. Differences in the percentage distribution between the control and the treatment groups losing RR were tested by χ2 test. All the experiments were conducted at room temperature. The percentage of toadlets losing RR increased with time of exposure to ethanol solution. The increase was significantly higher with the control than with the Nux-treated group. Nux Vomica 200 CH might have influenced the mid-brain of toadlets thereby countering the hypnotic effect of ethanol in the toadlets.

  2. Multi-Level Effects of Low Dose Rate Ionizing Radiation on Southern Toad, Anaxyrus [Bufo] terrestris.

    Directory of Open Access Journals (Sweden)

    Karolina Stark

    Full Text Available Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris during its pre-terrestrial stages of development -embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later, to four low dose rates of 137Cs at 0.13, 2.4, 21, and 222 mGy d-1, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay in red blood cells at a dose rate of 21 mGy d-1 and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.

  3. Multi-level effects of low dose rate ionizing radiation on southern toad, Anaxyrus [Bufo] terrestris

    International Nuclear Information System (INIS)

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development -embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of 137Cs at 0.13, 2.4, 21, and 222 mGy d-1, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21mGy d-1 and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae

  4. Isolation of radio-iodinated apical and basal-lateral plasma membranes of toad bladder epithelium.

    Science.gov (United States)

    Rodriguez, H J; Edelman, I S

    1979-04-01

    The apical and basal-lateral plasma membranes of toad bladder epithelium were radio-iodinated with the glucose-glucose oxidase-lactoperoxidase system. The covalently bound radio iodine was used as a marker during subcellular fractionation and membrane isolation. Homogenization conditions that ensured rupture of more than 80% of the cells without substantial nuclear damage were defined by Normarski optics. The nuclei were separated by differential centrifugation and the apical and basal-lateral components were resolved by differential and sucrose density gradient centrifugation. The apical components yielded two radioactive bands that were identified as glycocalyx and plasma membrane labeled with 125I. The basal-lateral components yielded a hetero-disperse pattern made up of at least 3 radioactive bands, but the bulk of the activity of ouabain-sensitive ATPase comigrated with only one of these bands. The mitochondia, identified by assays for cytochrome oxidase and NADH cytochrome c reductase activities, were separated from the radio-iodine labeled by centrifugation in sucrose density gradients under isokinetic conditions. The labeled glycocalyx and the slowly migrating components of basal-lateral labeling were separated from the radio-iodinated membranes by centrifugation at 100,000 x g x 1 hr after removal of the mitochrondria by the isokinetic method. The labeled membranes were then subjected to ultracentrifugation in sucrose density gradients under isopycnic conditions; the basal-lateral membranes containing ouabain-sensitive ATP-ase were well resolved from the apical membranes by this method. These results provide a relatively rapid method of attaining partial purification of the apical and basal-lateral plasma membranes of toad bladder epithelium. PMID:222911

  5. Density regulation in toad populations (Epidalea calamita, Bufotes viridis) by differential winter survival of juveniles.

    Science.gov (United States)

    Sinsch, Ulrich; Schäfer, Alena M

    2016-01-01

    The size of amphibian populations varies considerably between years, so that systematic trends in dynamics are difficult to detect. Informed conservation management of presumably declining populations requires the identification of the most sensitive life stage. In temperate-zone anurans there is growing evidence that juveniles hibernating for the first time suffer from substantial winter losses. In two syntopic toads (Epidalea calamita, Bufotes viridis) we monitored survival of such juveniles during four consecutive winters in the natural habitat and in four temperature treatments (3°, 5 °C, 10°/15 °C or 20 °C, natural light-dark cycle) in temperature-controlled chambers during winter. Specifically, we tested the hypotheses that (1) winter mortality of juvenile toads which hibernate for the first time in their life is an important component of population dynamics, and that (2) mortality rates differed between the two species. Parameters quantified were size-dependent winter mortality and body condition of pre- and post-hibernating juveniles. Field data provided evidence for the important role of winter mortality of first-hibernators in population dynamics. Choice of hibernacula differed in E. calamita between small and medium-sized individuals and also between the two species suggesting distinct mortality risks. The inability of small E. calamita to reach frost-proof hibernacula by burrowing, and the exposure of small B. viridis to predators are the most probable causes of size-assortative winter mortality. In conclusion, E. calamita juveniles may benefit from rising average winter temperatures in the future by decreased risk of freezing to death, whereas predator-caused winter mortality of B. viridis juveniles will also depend on the effects of climate warming on predator phenology.

  6. Frogs in the spotlight: a 16-year survey of native frogs and invasive toads on a floodplain in tropical Australia.

    Science.gov (United States)

    Brown, Gregory P; Shine, Richard

    2016-07-01

    Although widespread declines in anuran populations have attracted considerable concern, the stochastic demographics of these animals make it difficult to detect consistent trends against a background of spatial and temporal variation. To identify long-term trends, we need datasets gathered over long time periods, especially from tropical areas where anuran biodiversity is highest. We conducted road surveys of four anurans in the Australian wet-dry tropics on 4637 nights over a 16-year period. Our surveys spanned the arrival of invasive cane toads (Rhinella marina), allowing us to assess the invader's impact on native anuran populations. Our counts demonstrate abrupt and asynchronous shifts in abundance and species composition from one year to the next, not clearly linked to rainfall patterns. Typically, periods of decline in numbers of a species were limited to 1-2 years and were followed by 1- to 2-year periods of increase. No taxa showed consistent declines over time, although trajectories for some species showed significant perturbations coincident with the arrival of toads. None of the four focal frog species was less common at the end of the study than at the beginning, and three of the species reached peak abundances after toad arrival. Survey counts of cane toads increased rapidly during the initial stage of invasion but have subsequently declined and fluctuated. Distinguishing consistent declines versus stochastic fluctuations in anuran populations requires extensive time-series analysis, coupled with an understanding of the shifts expected under local climatic conditions. This is especially pertinent when assessing impacts of specific perturbations such as invasive species. PMID:27386087

  7. Checklist and Simple Identification Key for Frogs and Toads from District IV of The MADA Scheme, Kedah, Malaysia

    OpenAIRE

    Jaafar, Ibrahim; Chai, Teoh Chia; Sah, Shahrul Anuar Mohd; Akil, Mohd Abdul Muin Md.

    2009-01-01

    A survey was conducted to catalogue the diversity of anurans in District IV of the Muda Agriculture Development Authority Scheme (MADA) in Kedah Darul Aman, Malaysia, from July 1996 to January 1997. Eight species of anurans from three families were present in the study area. Of these, the Common Grass Frog (Fejevarya limnocharis) was the most abundant, followed by Mangrove Frog (Fejevarya cancrivora), Long-legged Frog (Hylarana macrodactyla), and Common Toad (Duttaphrynus melanostictus). Pudd...

  8. Lethal and sub-lethal effects on the Asian common toad Duttaphrynus melanostictus from exposure to hexavalent chromium.

    Science.gov (United States)

    Fernando, Vindhya A K; Weerasena, Jagathpriya; Lakraj, G Pemantha; Perera, Inoka C; Dangalle, Chandima D; Handunnetti, Shiroma; Premawansa, Sunil; Wijesinghe, Mayuri R

    2016-08-01

    Chromium discharged in industrial effluents frequently occurs as an environmental pollutant, but the lethal and sub-lethal effects the heavy metal might cause in animals exposed to it have been insufficiently investigated. Selecting the amphibian Duttaphrynus melanostictus, we carried out laboratory tests to investigate the effects of short and long term exposure to hexavalent chromium (Cr(VI)) in both tadpoles and adult toads. The concentrations used were 0.002, 0.02, 0.2, 1.0 and 2.0mg/L, the first three corresponding to field levels. In vitro exposures were also carried out using toad erythrocytes and Cr(VI) concentrations of 0.0015, 0.003, 0.015, 0.03, 0.15mg/L. Mortality, growth retardation, developmental delays and structural aberrations were noted in the metal-treated tadpoles, with increasing incidence corresponding to increase in Cr(VI) level and duration of exposure. Many of the sub-lethal effects were evident with long term exposure to environmentally relevant levels of the toxicant. Changes in selected blood parameters and erythrocyte morphometry were also detected in Cr(VI) exposed toads, indicating anaemic and leucopenic conditions. In the genotoxicity study, DNA damage indicated by comet assay and increased micronuclei frequency, occurred at the low Cr(VI) concentrations tested. The multiple deleterious effects of exposure to chromium signal the need for monitoring and controlling the discharge of chromium to the environment. The dose-dependency and genotoxic effects observed in this widely distributed Asian toad indicates its suitability for monitoring heavy metal pollution in aquatic systems. PMID:27262939

  9. Ultrastructure of the renal juxtaglomerular complex and peripolar cells in the axolotl (Ambystoma mexicanum) and toad (Bufo marinus).

    OpenAIRE

    Hanner, R H; Ryan, G B

    1980-01-01

    Renal juxtaglomerular regions were examined in the axolotl (Ambystoma mexicanum and toad (Bufo marinus). Prominent granulated peripolar epithelial cells were found surrounding the origin of the glomerular tuft in the axolotl. These cells resembled the peripolar cells recently discovered in mammalian species. They contained multiple electron-dense cytoplasmic granules, some of which showed a paracrystalline substructure and signs of exocytoxic activity. Such cells were difficult to find and sm...

  10. El concilio Vaticano II y su impacto en el campo episcopal argentino The Second Vatican Council and its impact on argentinian Episcopal field

    Directory of Open Access Journals (Sweden)

    Paulo Margaria

    2012-06-01

    Full Text Available El presente artículo busca explorar el impacto que tuvo el Concilio Vaticano II en la Iglesia Católica Argentina, haciendo especial hincapié en el campo de los obispos, desde una perspectiva socio-religiosa que pretende dar cuenta de la complejidad del campo católico. Para ello nos parece adecuado utilizar la noción de "campo" en términos bourdianos. Consideramos que hablar de "campo religioso" nos permite concebir el catolicismo como un espacio social dinámico y atravesado por constantes conflictos y luchas llevadas a cabo por grupos de agentes que intentan dominar dicho campo. Esto nos permitirá caracterizar las diversas posturas que el Concilio acentuará en el catolicismo argentino, actuando de este modo como un propulsor y legitimador de reflexiones y conflictos que existían previamente.This article examines the impact that Second Vatican Council had on argentinian Catholic Church, with special emphasis on the Bishops field, from a socio-religious perspective that seeks to explain the complexity of Catholic field. Therefore, it seems appropriate to use the Pierre Bourdieu's notion of "field". We believe that talk about "religious field" allows us to conceive Catholicism as a dynamic social space spanned by constant conflicts and struggles carried out by groups of agents who tried to dominate the field. Again, this allows us to characterize the positions that the Council emphasized in the Argentine Catholicism, acting as a propellant and legitimizing ideas and conflicts that existed previously.

  11. Survey of helminths, ectoparasites, and chytrid fungus of an introduced population of cane toads, Rhinella marina (Anura: Bufonidae), from Grenada

    Science.gov (United States)

    Drake, Michael C.; Zieger, Ulrike; Groszkowski, Andrew; Gallardo, Bruce; Sages, Patti; Reavis, Roslyn; Faircloth, Leslie; Jacobson, Krystin; Lonce, Nicholas; Pinckney, Rhonda D.; Cole, Rebecca Ann

    2014-01-01

    One hundred specimens of Rhinella marina, (Anura: Bufonidae) collected in St. George's parish, Grenada, from September 2010 to August 2011, were examined for the presence of ectoparasites and helminths. Ninety-five (95%) toads were parasitized by one or more parasite species. Nine species of parasites were found: 1 digenean, 2 acanthocephalans, 4 nematodes, 1 arthropod and 1 pentastome. The endoparasites represented 98.9% of the total number of parasite specimens collected. Grenada represents a new locality record for Mesocoelium monas, Raillietiella frenatus, Pseudoacanthacephalus sp., Aplectana sp., Physocephalus sp., Acanthacephala cystacanth and Physalopteridae larvae. The digenean M. monas occurred with the highest prevalence of 82%, contrasting many studies of R. marina where nematodes dominate the parasite infracommunity. Female toads were found to have a significantly higher prevalence of Amblyomma dissimile than male toads. Only two parasites exhibited a significant difference between wet and dry season with Parapharyngodon grenadensis prevalence highest in the wet season and A. dissimile prevalence highest during the dry season. Additionally, A. dissimile was significantly more abundant during the dry season.

  12. Effects of acute low temperature stress on the endocrine reactions of the Qinghai toad-headed lizard

    Institute of Scientific and Technical Information of China (English)

    Chunwang LI; Yuan GU; Songhua TANG; Hongxia FANG; Guohua JIANG; Zhigang JIANG

    2011-01-01

    Endocrinological action is generally thought to be a way for animals to respond to stress at low temperatures.To learn the role of hormones in eetotherms inhabiting alpine environments,we studied the effects of acute low temperature exposure on the endocrinological reactions of Qinghai toad-headed lizards in the Qinghai-Tibetan Plateau.We monitored plasma corticosterone and insulin concentration of the lizards under five low temperature treatments.We found no significant difference in plasma corticosterone or insulin in lizards among our five different treatments.For males and females the correlation between plasma corticosterone and insulin concentrations was not significant.In contrast to other studies on reptiles at low altitude,we suggest that due to the alpine environment (low temperature and low oxygen concentration) they inhabit,Qinghai toad-headed lizards respond to experimental cold stress slightly to mobilize energy and live their vivid life.In addition,corticosterone and insulin of Qinghai toad-headed lizards are secreted independently along with low temperature treatments [Current Zoology 57 (6):775-780,2011].

  13. Natural and experimental infection of the lizard Ameiva ameiva with Hemolivia stellata (Adeleina: Haemogregarinidae) of the toad Bufo marinus.

    Science.gov (United States)

    Lainson, R; De Souza, M C; Franco, C M

    2007-12-01

    Developmental stages of a haemogregarine in erythrocytes of the lizard Ameiva ameiva (Teiidae), from Pará State, north Brazil, were shown to be those of Hemolivia by the nature of the parasite's sporogonic cycle in the tick Amblyomma rotondatum. The type species, Hemolivia stellata Petit et al., 1990 was described in the giant toad Bufo marinus and the tick Amblyomma rotondatum, also from Pará State, and in view of the fact that A. ameiva and Bufo marinus share the same habitat and are both commonly infested by A. rotondatum, the possibility that the parasite of A. ameiva is H. stellata had to be considered. Uninfected lizards fed with material from infected ticks taken from B. marinus, and others fed with liver of toads containing tissue-cysts of H. stellata, were shown to subsequently develop typical Hemolivia infections, with all stages of the development similar to those seen in the naturally infected lizards. Conversely, a juvenile, uninfected toad became infected when fed with sporocysts of Hemolivia in a macerated tick that had fed on an infected A. ameiva and pieces of liver containing tissuecysts from the same lizard. The remarkable lack of host specificity shown by H. stellata, in hosts so widely separated as an amphibian and a reptile, is discussed. PMID:18225421

  14. Natural and experimental infection of the lizard Ameiva ameiva with Hemolivia stellata (Adeleina: Haemogregarinidae of the toad Bufo marinus

    Directory of Open Access Journals (Sweden)

    Lainson R.

    2007-12-01

    Full Text Available Developmental stages of a haemogregarine in erythrocytes of the lizard Ameiva ameiva (Teiidae, from Pará State, north Brazil, were shown to be those of Hemolivia by the nature of the parasite’s sporogonic cycle in the tick Amblyomma rotondatum. The type species, Hemolivia stellata Petit et al., 1990 was described in the giant toad Bufo marinus and the tick Amblyomma rotondatum, also from Pará State, and in view of the fact that A. ameiva and Bufo marinus share the same habitat and are both commonly infested by A. rotondatum, the possibility that the parasite of A. ameiva is H. stellata had to be considered. Uninfected lizards fed with material from infected ticks taken from B. marinus, and others fed with liver of toads containing tissuecysts of H. stellata, were shown to subsequently develop typical Hemolivia infections, with all stages of the development similar to those seen in the naturally infected lizards. Conversely, a juvenile, uninfected toad became infected when fed with sporocysts of Hemolivia in a macerated tick that had fed on an infected A. ameiva and pieces of liver containing tissue-cysts from the same lizard. The remarkable lack of host specificity shown by H. stellata, in hosts so widely separated as an amphibian and a reptile, is discussed.

  15. Intoxicação por veneno de sapo em um canino Toad venom intoxication in a dog

    Directory of Open Access Journals (Sweden)

    Luciana Sonne

    2008-09-01

    Full Text Available O sapo do gênero Bufo possui nas suas glândulas paratóides uma secreção mucóide contendo toxinas como bufaginas e Bufotoxinas, que são esteróides cardiogênicos. Os cães podem atacar os sapos, entrando em contato com o veneno por meio das mucosas. Um canino, da raça Bulldog Francês, foi encaminhado ao Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (UFRGS para a necropsia com histórico de provável intoxicação por veneno de sapo. Na necropsia o canino apresentava pulmões aumentados de volume, avermelhados e com edema, e rins de coloração vermelho-escura. As alterações microscópicas indicaram congestão, hemorragia e edema pulmonar. Nos rins, no baço e nos linfonodos foi observada congestão. As análises toxicológicas para os venenos de rotina foram negativas. Porém, a investigação do veneno de sapo a partir de cromatografia por camada delgada e gasosa demonstrou resultado positivo, revelando ser esta a causa da morte do canino.The toads of the genus Bufo produce, in their parotoid glands, a mucoid secretion containing toxins such as bufagins and Bufotoxins, which are cardiogenic steroids. The mucous membranes of dogs can absorb this venom when they attack the toads. A French bulldog with a history of probable toad venom intoxication was referred to Veterinary Pathology Section of Federal University of Rio Grande do Sul (UFRGS for necropsy. The necropsy revealed enlarged, reddish, edematous lungs, and kidneys displaying a dark red color. The microscopic alterations indicated the presence of congestion, hemorrhage, and pulmonary edema. Congestion was observed in the kidneys, spleen and lymph nodes. The routine toxicological analyses for venom detection were negative. Nevertheless, the toad venom test result was positive as assessed by thin layer and gas chromatography, indicating that toad venom intoxication was the cause of death.

  16. Evolution of rapid development in spadefoot toads is unrelated to arid environments.

    Science.gov (United States)

    Zeng, Cen; Gomez-Mestre, Ivan; Wiens, John J

    2014-01-01

    The extent to which species' life histories evolve to match climatic conditions is a critical question in evolutionary biology and ecology and as human activities rapidly modify global climate. GIS-based climatic data offer new opportunities to rigorously test this question. Superficially, the spadefoot toads of North America (Scaphiopodidae) seem to offer a classic example of adaptive life-history evolution: some species occur in extremely dry deserts and have evolved the shortest aquatic larval periods known among anurans. However, the relationships between the climatic conditions where spadefoots occur and the relevant life-history traits have not been explicitly tested. Here, we analyzed these relationships using GIS-based climatic data, published life-history data, and a time-calibrated phylogeny for pelobatoid frogs. Surprisingly, we find no significant relationships between life-history variables and precipitation or aridity levels where these species occur. Instead, rapid development in pelobatoids is strongly related to their small genome sizes and to phylogeny. PMID:24800832

  17. Analysis of heart rate control to assess thermal sensitivity responses in Brazilian toads.

    Science.gov (United States)

    Natali, J E S; Santos, B T; Rodrigues, V H; Chauí-Berlinck, J G

    2015-01-01

    In anurans, changes in ambient temperature influence body temperature and, therefore, energy consumption. These changes ultimately affect energy supply and, consequently, heart rate (HR). Typically, anurans living in different thermal environments have different thermal sensitivities, and these cannot be distinguished by changes in HR. We hypothesized that Rhinella jimi (a toad from a xeric environment that lives in a wide range of temperatures) would have a lower thermal sensitivity regarding cardiac control than R. icterica (originally from a tropical forest environment with a more restricted range of ambient temperatures). Thermal sensitivity was assessed by comparing animals housed at 15° and 25°C. Cardiac control was estimated by heart rate variability (HRV) and heart rate complexity (HRC). Differences in HRV between the two temperatures were not significant (P=0.214 for R. icterica and P=0.328 for R. jimi), whereas HRC differences were. All specimens but one R. jimi had a lower HRC at 15°C (all Pthermal sensitivity and that cardiac control is not completely dependent on the thermal environment because HRC was not consistently different between temperatures in all R. jimi specimens. This result indicates a lack of evolutive trade-offs among temperatures given that heart rate control at 25°C is potentially not a constraint to heart rate control at 15°C.

  18. The toxicity of glyphosate alone and glyphosate-surfactant mixtures to western toad (Anaxyrus boreas) tadpoles.

    Science.gov (United States)

    Vincent, Kim; Davidson, Carlos

    2015-12-01

    Pesticide choice based on toxicity to nontarget wildlife is reliant on available toxicity data. Despite a number of recent studies examining the effects of glyphosate on amphibians, very few have aimed to understand the toxicological effects of glyphosate in combination with surfactants as it is commonly applied in the field. Land managers interested in making pesticide choices based on minimizing impacts to nontarget wildlife are hindered by a lack of published toxicity data. Short-term acute toxicity trials were conducted for glyphosate in the form of isopropylamine salt (IPA) alone and mixed with 2 surfactants: Agri-dex and Competitor with western toad (Anaxyrus [Bufo] boreas) tadpoles. Glyphosate IPA mixed with Competitor was 6 times more toxic than glyphosate IPA mixed with Agri-dex, and both mixtures were more toxic than glyphosate IPA alone. The median lethal concentrations reported for 24-h and 48-h exposures were 8279 mg/L (24 h) and 6392 mg/L (48 h) for glyphosate IPA alone; 5092 mg/L (24 h) and 4254 mg/L (48 h) for glyphosate IPA mixed with Agri-dex; and 853 mg/L (24 h) and 711 mg/L (48 h) for glyphosate IPA mixed with Competitor. The present study indicates that the toxicity of a tank mix may be greatly increased by the addition of surfactants and may vary widely depending on the specific surfactant.

  19. Ultrastructural and Molecular Changes in the Developing Small Intestine of the Toad Bufo regularis

    Directory of Open Access Journals (Sweden)

    S. A. Sakr

    2014-01-01

    Full Text Available The ontogenetic development of the small intestine of the toad Bufo regularis was investigated using twofold approaches, namely, ultrastructural and molecular. The former has been done using transmission electron microscope and utilizing the developmental stages 42, 50, 55, 60, 63, and 66. The most prominent ultrastructural changes were recorded at stage 60 and were more evident at stage 63. These included the appearance of apoptotic bodies/nuclei within the larval epithelium, the presence of macrophages, swollen mitochondria, distorted rough endoplasmic reticulum, chromatin condensation, and irregular nuclear envelop, and the presence of large vacuoles and lysosomes. The molecular investigation involved examining DNA content and fragmentation. The results showed that the DNA content decreased significantly during the metamorphic stages 60 and 63 compared with both larval (50 and 55 and postmetamorphic (66 stages. The metamorphic stages (60 and 63 displayed extensive DNA laddering compared with stages 50, 55, and 66. The percentage of DNA damage was 0.00%, 12.91%, 57.26%, 45.48%, and 4.43% for the developmental stages 50, 55, 60, 63, and 66, respectively. In conclusion, the recorded remodeling of the small intestine represents a model for clarifying the mechanism whereby cell death and proliferation are controlled.

  20. Urea transport across urinary bladder and salt acclimation in toad (Bufo viridis).

    Science.gov (United States)

    Shpun, S; Katz, U

    1990-04-01

    The fluxes of urea across the urinary bladder of the toad Bufo viridis have been studied under conditions of acclimation to tap water or 500 mosM NaCl solution. The [14C]urea fluxes were measured simultaneously with [3H]inulin to test for nonspecific leakage. The fluxes are quite high (Ktrans = 75 x 10(-7) cm/s at 5 mmol/l urea) and are similar in either the mucosal-to-serosal or the opposite direction. "Summer" rates were five to six times higher than the "winter" rates. Antidiuretic hormone (ADH), theophylline, and forskolin increased the fluxes to variable degrees (two to five times), similar in the two acclimation conditions. Phloretin inhibited the urea fluxes by nearly 50%. 1,3-Dimethylurea and thiourea, but not acetamide, competed with the urea fluxes effectively. The fluxes of urea were not affected by the osmotic water flow, although both responded to ADH. It is concluded that urea transport across the urinary bladder of B. viridis is by facilitated diffusion through a specific pathway independent of water flux. The inhibitory effect of the structural analogues on the urea flux was affected by salt acclimation, whereas most other characteristics did not differ significantly at 5 mmol/l external urea under the two conditions of acclimation. PMID:2331031

  1. Deep genetic structure and ecological divergence in a widespread human commensal toad.

    Science.gov (United States)

    Wogan, Guinevere O U; Stuart, Bryan L; Iskandar, Djoko T; McGuire, Jimmy A

    2016-01-01

    The Asian common toad (Duttaphrynus melanostictus) is a human commensal species that occupies a wide variety of habitats across tropical Southeast Asia. We test the hypothesis that genetic variation in D. melanostictus is weakly associated with geography owing to natural and human-mediated dispersal facilitated by its commensal nature. Phylogenetic and population genetic analyses of mitochondrial and nuclear DNA sequence variation, and predictive species distribution modelling, unexpectedly recovered three distinct evolutionary lineages that differ genetically and ecologically, corresponding to the Asian mainland, coastal Myanmar and the Sundaic islands. The persistence of these three divergent lineages, despite ample opportunities for recent human-mediated and geological dispersal, suggests that D. melanostictus actually consists of multiple species, each having narrower geographical ranges and ecological niches, and higher conservation value, than is currently recognized. These findings also have implications for the invasion potential of this human commensal elsewhere, such as in its recently introduced ranges on the islands of Borneo, Sulawesi, Seram and Madagascar. PMID:26763213

  2. A new species of flea-toad (Anura: Brachycephalidae) from southern Atlantic Forest, Brazil.

    Science.gov (United States)

    Condez, Thais Helena; Monteiro, Juliane Petry De Carli; Comitti, Estevão Jasper; Garcia, Paulo Christiano De Anchietta; Amaral, Ivan Borel; Haddad, Célio Fernando Baptista

    2016-01-01

    We describe a new species of Brachycephalus that is morphologically similar to the flea-toads B. didactylus, B. hermogenesi, and B. pulex. The new species occurs from the sea level up to 1000 m and it is widely distributed throughout southern Atlantic Forest. Brachycephalus sulfuratus sp. nov. is distinguished from all of its congeners by the combination of the following characters: (1) small body size (SVL of adults: 7.4-8.5 mm for males and 9.0-10.8 mm for females); (2) "leptodactyliform" body; (3) pectoral girdle arciferal and less robust compared to the Brachycephalus species with "bufoniform" body; (4) procoracoid and epicoracoid fused with coracoid but separated from the clavicle by a large fenestrae; (5) toe I externally absent; toes II, III, IV, and V distinct; phalanges of toes II and V reduced; (6) skin smooth with no dermal ossifications; (7) in life, general background color brown with small dark-brown spots; skin of throat, chest, arms, and forearms with irregular yellow blotches; in ventral view, cloacal region of alive and preserved specimens surrounded by a dark-brown inverted v-shaped mark outlined with white; (8) advertisement call long, composed of a set of 4-7 high-frequency notes (6.2-7.2 kHz) repeated regularly. PMID:27394218

  3. Effects of ADH on the apical and basolateral membranes of toad urinary bladder epithelial cells.

    Science.gov (United States)

    Donaldson, P J; Leader, J P

    1993-11-01

    Short-circuited urinary bladders from Bufo marinus were supported on their apical surface by an agar mounting method and impaled with microelectrodes via their basolateral membrane. This arrangement provided stable and long-lasting impalements of epithelial cells and yielded reliable membrane potentials and voltage divider ratios (Ra/Rb), where Ra and Rb are apical and basolateral membrane resistances respectively. The membrane potential under short-circuit conditions (Vsc) was -51.4 +/- 2.2 mV (n = 59), while under open-circuit conditions apical membrane potential (Va) and basolateral membrane potential (Vb) were -31.0 +/- 2.4 and 59.5 +/- 2.4 mV, respectively. This yields a "well-shaped" potential profile across the toad urinary bladder, where Va is inversely related to the rate of transport, Isc. Antidiuretic hormone (ADH) produced a hyperpolarisation of Vsc and Vb but had no significant effect on Va. In addition, Ra/Rb was significantly increased by ADH (4.6 +/- 0.5 to 10.2 +/- 3.6). Calculation of individual membrane resistances following the addition of amiloride showed that ADH produced a parallel decrease in Ra and Rb membrane resistance, with the observed increase in Ra/Rb being due to a greater percentage decrease in Rb than in Ra. The ability of ADH to effect parallel changes in apical and basolateral membrane conductance helps to maintain a constant cellular volume despite an increase in transepithelial transport. PMID:8309781

  4. Studies on the physiological function of spermine in the process of progesterone induced toad oocyte maturation

    Institute of Scientific and Technical Information of China (English)

    LIRUNSHENG; JIAKETSO

    1992-01-01

    Spermidine or spermine but not putrescine inhibited progesterone induced Bufo bufo gargarizans oocyte maturation.The ID50 for spermine inhibition via intra -oocyte microinjection on maturation induced by progesterone was 6.8mM(100nl).Spermine could inhibit MPF induced toad oocyte maturation with a much higher ID50.A 55 kD protein was dephosphorylated during the process of progesterone induced oocyte maturation .Spermine selectively promoted the level of phosphorylation of this protein in both progesterone-stimulated and hormone-untreated oocytes.The extent of its dephosphorylation was fairly Correlated with the percentage of GVBD in the hormone stimulated oocytes.The level of endogenous spermine was reduced by 28% between the perod of 0.40 GVBD50 and 0.60 GVBD50,at which 55 kD protein was dephosphorylated.Spermine inhibited progesterone-stimulated protein synthesis in almost the same dose dependent manner as its inhititory effect on the hormone-induced maturation,The endogenous spermine regulated 55 kD protein dephosphorylation which may trigger the increase of protein dephosphorylation which may trigger the increase of protein synthesis and in turn promote the activation of MPF,It is possible that 55 kD protein may be one of the components of messenger ribonucleoprotein(mRNP) particles.

  5. Genomewide scan for adaptive differentiation along altitudinal gradient in the Andrew's toad Bufo andrewsi.

    Science.gov (United States)

    Guo, Baocheng; Lu, Di; Liao, Wen Bo; Merilä, Juha

    2016-08-01

    Recent studies of humans, dogs and rodents have started to discover the genetic underpinnings of high altitude adaptations, yet amphibians have received little attention in this respect. To identify possible signatures of adaptation to altitude, we performed a genome scan of 15 557 single nucleotide polymorphisms (SNPs) obtained with restriction site-associated DNA sequencing of pooled samples from 11 populations of Andrew's toad (Bufo andrewsi) from the edge of the Tibetan Plateau, spanning an altitudinal gradient from 1690 to 2768 m.a.s.l. We discovered significant geographic differentiation among all sites, with an average FST   = 0.023 across all SNPs. Apart from clear patterns of isolation by distance, we discovered numerous outlier SNPs showing strong associations with variation in altitude (1394 SNPs), average annual temperature (1859 SNPs) or both (1051 SNPs). Levels and patterns of genetic differentiation in these SNPs were consistent with the hypothesis that they have been subject to directional selection and reflect adaptation to altitudinal variation among the study sites. Genes with footprints of selection were significantly enriched in binding and metabolic processes. Several genes potentially related to high altitude adaptation were identified, although the identity and functional significance of most genomic targets of selection remain unknown. In general, the results provide genomic support for results of earlier common garden and low coverage genetic studies that have uncovered substantial adaptive differentiation along altitudinal and latitudinal gradients in amphibians. PMID:27289071

  6. The cane or marine toad, Rhinella marina (Anura, Bufonidae): two genetically and morphologically distinct species.

    Science.gov (United States)

    Acevedo, Aldemar A; Lampo, Margarita; Cipriani, Roberto

    2016-04-18

    Rhinella marina is a Neotropical toad that has been introduced widely worldwide. Its toxic effects to frog-eating predators threaten the native and domestic fauna of some regions where it has been introduced. Despite previous studies suggesting two genetically distinct cryptic species within R. marina, one east and one west of the Andes, its taxonomic status remained unresolved due to the absence of morphological complementary evidence. For the first time, data from two mitochondrial genes (ND3 and CR) and 23 morphometric landmarks are combined to evaluate the taxonomic status of this species. Our results support the hypothesis of two separate evolutionary lineages within R. marina and demonstrate that these lineages have significantly diverged in skull shape. We identified two distinct morphotypes, one eastern and one Andean western, with no overlapping morphospaces. The geographic pattern of genetic variation was consistent with a stable structured population with no evidence of recent demographic or geographic expansions. The concordance between the observed geographic patterns in morphometric and genic traits calls for the recognition of two species under R. marina name.

  7. keratinized nuptial spines are used for male combat in the emei moustache toad (leptobrachium boringii)

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    we describe the natural history and reproductive behaviour of the emei moustache toad (leptobrachium boringii)with an emphasis on the development of keratinized nuptial spines in males and document combat behaviour for the first time in this species.between february and march of 2011,19 female and 43 male l.boringii from mount emei unesco world heritage site,sichuan,china were observed throughout the breeding season.this species exhibits male-biased sexual size dimorphism (ssd)with limited evidence of paternal care (nest guarding by males).prior to the breeding season males grow 10-16 keratinized spines on their upper lip,which fall off once the season has ended.throughout the breeding season males construct and defend aquatic nests where they produce advertisement calls to attract females.during this time we documented 14 cases involving a total of 22 males where males used their moustaches for aggressive interaction.combat typically occurred at the beginning of the season when males would compete for a limited number of available nest sites.neither male body size,nor body condition significantly affects the outcome of an aggressive interaction,suggesting that size may not be the only factor influencing an individual's chance of victory.our evidence for male competition and aggression,along with observed paternal care are potential mechanisms to explain the evolution of male-biased ssd observed in this species.

  8. Phylogeography and demography of Guianan harlequin toads (Atelopus): diversification within a refuge.

    Science.gov (United States)

    Noonan, Brice P; Gaucher, Philippe

    2005-09-01

    We investigated the genetic structure of populations of Guianan harlequin toads (genus Atelopus) and their evolutionary affinities to extra-Guianan congeners. Phylogenetic analysis of mitochondrial cytochrome b (cyt b) and NADH dehydrogenase subunit 2 (ND2) gene sequences produced well-supported clades largely corresponding to the four recognized taxa in the Guianas (Atelopus spumarius hoogmoedi, Atelopus spumarius barbotini, Atelopus franciscus, and Atelopus flavescens). Our findings suggest that the Guianan A. spumarius represent distinct evolutionary lineages that merit distinction from Amazonian conspecifics, and that the status of A. flavescens and A. franciscus is somewhat less clear. Approximately 69% of the observed genetic variation is accounted for by differences between these four recognized taxa. Coalescent-based estimates of gene flow between taxa suggest that these lineages are largely isolated from one another. Negligible rates of migration between populations and significant divergence within such close proximity suggests that although the region inhabited by these taxa is almost entirely undisturbed, significant habitat heterogeneity exists as to have produced a remarkable diversification of Atelopus within the eastern Guiana Shield. These results contradict the commonly held view of the Guiana Shield as a 'refuge' whose stability during late Tertiary and Quaternary climatic fluctuations served as a biotic reservoir. Instead, we provide evidence that climatic fluctuations during this time had a diversifying effect within the Guianan region. PMID:16101771

  9. Buforins: histone H2A-derived antimicrobial peptides from toad stomach.

    Science.gov (United States)

    Cho, Ju Hyun; Sung, Bong Hyun; Kim, Sun Chang

    2009-08-01

    Antimicrobial peptides (AMPs) constitute an important component of the innate immune system in a variety of organisms. Buforin I is a 39-amino acid AMP that was first isolated from the stomach tissue of the Asian toad Bufo bufo gargarizans. Buforin II is a 21-amino acid peptide that is derived from buforin I and displays an even more potent antimicrobial activity than its parent AMP. Both peptides share complete sequence identity with the N-terminal region of histone H2A that interacts directly with nucleic acids. Buforin I is generated from histone H2A by pepsin-directed proteolysis in the cytoplasm of gastric gland cells. After secretion into the gastric lumen, buforin I remains adhered to the mucous biofilm that lines the stomach, thus providing a protective antimicrobial coat. Buforins, which house a helix-hinge-helix domain, kill a microorganism by entering the cell without membrane permeabilization and thus binding to nucleic acids. The proline hinge is crucial for the cell penetrating activity of buforins. Buforins also are known to possess anti-endotoxin and anticancer activities, thus making these peptides attractive reagents for pharmaceutical applications. This review describes the role of buforins in innate host defense; future research paradigms; and use of these agents as human therapeutics.

  10. Sexual dimorphism in baseline urinary corticosterone metabolites and their association with body-condition indices in a peri-urban population of the common Asian toad (Duttaphrynus melanostictus).

    Science.gov (United States)

    Narayan, Edward J; Gramapurohit, Narahari P

    2016-01-01

    Field endocrinology research through the quantification of glucocorticoids or stress hormones in free-living wildlife is crucial for assessing their physiological responses towards pervasive environmental changes. Urinary corticosterone metabolite (UCM) enzyme-immunoassay (EIA) has been validated for numerous amphibian species as a non-invasive measure of physiological stress. Body-condition indices (BCIs) have also been widely used in amphibians as an indirect measure of animal health. Field endocrinology research on amphibian species in Asia is limited. In this study, we validated a UCM EIA in a peri-urban sub-population of the common Asian toad (Duttaphrynus melanostictus) in Pune, Maharashtra, India. We determined the baseline levels of UCMs in male (n=39) and female (n=19) toads. Secondly, we used a standard capture handling protocol to quantify changes in UCMs during short-term captivity. We also determined BCIs in the male and female toads using Fulton's index (K) and residual condition index (RCI). The results showed that mean baseline levels of UCMs were significantly higher in male toads than in females. There was no significant change in mean levels of UCMs of males and females between capture and captivity (0-12h). This highlights plausible habituation of the species to the peri-urban environment. Associations between UCMs with BCIs (K and R) were positive in male toads but negative in females. In conclusion, our UCMs EIA can be applied with BCIs to assess health of the Asian toads. We also suggest that direct fitness parameters such as sperm and oocyte quality, reproductive ecology and immunocompetence measurements should be applied in combination with these conservation physiology tools to quantify the fitness consequences of pervasive environmental changes on native amphibians. PMID:26478192

  11. Breeding pond selection and movement patterns by eastern spadefoot toads (Scaphiopus holbrookii) in relation to weather and edaphic conditions.

    Energy Technology Data Exchange (ETDEWEB)

    Greenberg, Cathryn H. [USDA Forest Service, New Ellenton, SC (United States); Tanner, George W. [USDA Forest Service, New Ellenton, SC (United States)

    2004-08-31

    Cathryn H. Greenberg and George W. Tanner. 2004. Breeding pond selection and movement patterns by eastern spadefoot toads (Scaphiopus holbrookii) in relation to weather and edaphic conditions. J. Herp. 38(4):569-577. Abstract: Eastern Spadefoot Toads (Scaphiopus holbrookii) require fish-free, isolated, ephemeral ponds for breeding but otherwise inhabit the surrounding uplands, commonly xeric longleaf pine (Pinus palustris) wiregrass (Aristida beyrichiana). Hence both pond and upland conditions can potentially affect their breeding biology, and population persistence. Hardwood invasion due to fire suppression in sandhills could alter upland and pond suitability by higher hardwood density and increased transpiration. In this paper we explore breeding and neonatal emigration movements in relation to weather, hydrological conditions of ponds, and surrounding upland matrices. We use 9 years of data from continuous monitoring with drift fences and pitfall traps at 8 ephemeral ponds in 2 upland matrices: regularly-burned, savanna-like sandhills (n = 4), and hardwood-invaded sandhills (n = 4). Neither adult nor neonate captures differed between ponds within the 2 upland matrices, suggesting that they are tolerant of upland heterogeneity created by fire frequency. Explosive breeding occurred during 9 periods and in all seasons; adults were captured rarely otherwise. At a landscape-level rainfall, maximum change in barometric pressure, and an interaction between those 2 variables were significant predictors of explosive breeding. At a pond-level, rainfall, change in pond depth during the month prior to breeding, and days since a pond was last dry were significant predictors of adult captures. Transformation date, rather than weather, was associated with neonatal emigrations, which usually were complete within a week. Movement by first-captured adults and neonates was directional, but adult emigrations were apparently not always toward their origin. Our results suggest that

  12. Patterns of Genetic Variability in Island Populations of the Cane Toad (Rhinella marina) from the Mouth of the Amazon

    Science.gov (United States)

    Bessa-Silva, Adam Rick; Vallinoto, Marcelo; Sodré, Davidson; da Cunha, Divino Bruno; Hadad, Dante; Asp, Nils Edvin; Sampaio, Iracilda; Schneider, Horacio; Sequeira, Fernando

    2016-01-01

    The Amazonian coast has several unique geological characteristics resulting from the interaction between drainage pattern of the Amazon River and the Atlantic Ocean. It is one of the most extensive and sedimentologically dynamic regions of the world, with a large number of continental islands mostly formed less than 10,000 years ago. The natural distribution of the cane toad (Rhinella marina), one of the world’s most successful invasive species, in this complex Amazonian system provides an intriguing model for the investigation of the effects of isolation or the combined effects of isolation and habitat dynamic changes on patterns of genetic variability and population differentiation. We used nine fast-evolving microsatellite loci to contrast patterns of genetic variability in six coastal (three mainlands and three islands) populations of the cane toad near the mouth of the Amazon River. Results from Bayesian multilocus clustering approach and Discriminant Analyses of Principal Component were congruent in showing that each island population was genetically differentiated from the mainland populations. All FST values obtained from all pairwise comparisons were significant, ranging from 0.048 to 0.186. Estimates of both recent and historical gene flow were not significantly different from zero across all population pairs, except the two mainland populations inhabiting continuous habitats. Patterns of population differentiation, with a high level of population substructure and absence/restricted gene flow, suggested that island populations of R. marina are likely isolated since the Holocene sea-level rise. However, considering the similar levels of genetic variability found in both island and mainland populations, it is reliable to assume that they were also isolated for longer periods. Given the genetic uniqueness of each cane toad population, together with the high natural vulnerability of the coastal regions and intense human pressures, we suggest that these

  13. Natural and experimental infection of the lizard Ameiva ameiva with Hemolivia stellata (Adeleina: Haemogregarinidae) of the toad Bufo marinus

    OpenAIRE

    Lainson R.; De Souza M.C.; Franco C.M.

    2007-01-01

    Developmental stages of a haemogregarine in erythrocytes of the lizard Ameiva ameiva (Teiidae), from Pará State, north Brazil, were shown to be those of Hemolivia by the nature of the parasite’s sporogonic cycle in the tick Amblyomma rotondatum. The type species, Hemolivia stellata Petit et al., 1990 was described in the giant toad Bufo marinus and the tick Amblyomma rotondatum, also from Pará State, and in view of the fact that A. ameiva and Bufo marinus share the same habitat and are both c...

  14. The dynamics of venous return and response to hypervolemia in the toad, Bufo marinus (L.

    Directory of Open Access Journals (Sweden)

    Toews Daniel P

    2001-10-01

    Full Text Available Abstract Background Venous return from the posterior region of amphibians travels by either two renal portal veins to the kidney or a central abdominal vein that drains into the hepatic portal system. The relative proportions of blood flow in these vessels has never been measured nor has a modification of flow been determined when venous return increases by changes in blood volume during hypervolemia or during increased volume input from the posterior lymph hearts. Results Venous return from the posterior region of Bufo marinus was measured under resting conditions and in response to a systemic hypervolemia. Doppler flow probes were positioned on the renal portal and ventral abdominal veins, and flow was recorded as injections of artificial plasma equaling 100% of the animal's plasma volume were administered through the sciatic artery. Resting flow was found to be 5.54 ± 2.03 ml min-1 kg-1 in the paired renal portal veins, and 7.31 ± 0.89 ml min-1 kg-1 in the ventral abdominal vein. While renal portal flow was found to increase by a factor of 2.4 times during the first 10 min of hypervolemia, ventral abdominal flow only increased by a factor of 1.3. Conclusions Our results quantify the contribution to circulation from posterior venous return in the toad Bufo marinus. A preferential movement of excess fluid through the renal portal pathway was also demonstrated, supporting the possibility of water elimination via the renal portal circulation, especially during periods of high water influx into the animals.

  15. Malformations and mortality in the Asian Common Toad induced by exposure to pleurolophocercous cercariae (Trematoda: Cryptogonimidae).

    Science.gov (United States)

    Jayawardena, Uthpala A; Tkach, Vasyl V; Navaratne, Ayanthi N; Amerasinghe, Priyanie H; Rajakaruna, Rupika S

    2013-06-01

    Malformations and increased mortality due to infection by the digenetic trematode, Riberioa ondatrae have been reported for many species of amphibians. Severe malformations have also been reported in the Common Hourglass Tree Frog, Polypedates cruciger induced by pleurolophocercous cercariae in Sri Lanka in addition to the changes in the behaviour, development and survival of the host. We exposed pre-limb bud stage tadpoles (Gosner stages 25-26) of the Asian Common Toad, Duttaphrynus melanostictus to the same pleurolophocercous type cercariae under laboratory conditions. Molecular and morphological identification showed that these cercariae belonged Acanthostomum burminis infecting freshwater snakes as definitive hosts. These cercariae induced malformations (27.8%) and reduced survival to metamorphosis (53.8%). The magnitude of the effects increased with the dose of cercariae. Types of malformations were mainly axial, such as scoliosis and kyphosis. Severe limb malformations such as extra or missing limbs as reported for amphibians exposed to R. ondatrae were not observed in the D. melanostictus. Same authors reported a higher percentage of malformations previously when P. cruciger was exposed to the cercariae A. burminis compared to D. melanostictus. However, tadpoles of D. melanostictus, which are smaller compared to those of P. cruciger, experienced higher mortality than P. cruciger tadpoles. Trematode induced malformations and mortality in amphibians are highly variable and depend on multiple factors such as host species differences such as resistance to infection and tolerance, life-history characteristics such as size at metamorphosis and length of the metamorphosis period, and other factors such as size of the amphibian at the time of trematode exposure. PMID:23353759

  16. The influence of ambient salinity and temperature on lipid metabolism in toad (Bufo bufo) skin. Is phosphatidylethanolamine an endogenous regulator of ion channels?

    DEFF Research Database (Denmark)

    Hansen, H.J.M.; Olsen, Allan Gylling; Willumsen, Niels J.

    1994-01-01

    ) were found in vivo, when toads adapted to Ringer solution were transferred to tap water containing tracer amounts of (32P) phosphate and (14C) acetate. PE could play a role in the formation of a "hydrophilic" environment and thereby, e.g. stabilise the integral membrane proteins that regulate...

  17. Microsatellite analysis of the natterjack toad (Bufo calamita) in Denmark: populations are islands in a fragmented landscape

    DEFF Research Database (Denmark)

    Allentoft, Morten Erik; Siegismund, Hans Redlef; Briggs, Lars;

    2009-01-01

    The European natterjack toad (Bufo calamita) has declined rapidly in recent years, primarily due to loss of habitat, and in Denmark it is estimated that 50% of the isolated populations are lost each decade. To efficiently manage and conserve this species and its genetic diversity, knowledge...

  18. Spitzer Observations of Var Her 04: Possible Detection of Dust Formation in a Super-Outbursting TOAD

    CERN Document Server

    Ciardi, D R; Hoard, D W; Howell, S B; Van Belle, G T; Ciardi, David R.; Wachter, Stefanie; Howell, Steve B.; Belle, Gerard T. van

    2006-01-01

    We present four MIPS (24 \\micron) and two IRAC (3.6, 4.5, 5.8, and 8.0 \\micron) Spitzer observations of the newly discovered Tremendous Outburst Amplitude Dwarf nova (TOAD) Var Her 04 during decline from super-outburst. The four MIPS observations span 271 days and the two IRAC observations span 211 days. Along the line-of-sight to Var Her 04, there is a foreground M-star within 1\\arcsec of the variable; as a result, all of the Spitzer photometry presented in this paper is a blend of the foreground M-star and Var Her 04. We estimate the quiescent level of the TOAD to be $\\Delta V=4-5$ magnitudes below that of the M-star. Based upon the spectral energy distribution and the 2MASS colors, we find the M-star to be an M3.5V dwarf at a distance of 80-130 pc. Based upon its outburst amplitude and quiescent apparent magnitude, we estimate the distance to Var Her 04 to be 200-400 pc, suggesting that the line-of-sight foreground star is physically unrelated to the cataclysmic variable. All of the Spitzer photometry is c...

  19. Influence of sprint speed and body size on predator avoidance in New Mexican spadefoot toads (Spea multiplicata).

    Science.gov (United States)

    Arendt, Jeffrey David

    2009-03-01

    Predator-prey interactions play an important role in community dynamics and may be important for promoting genetic diversification. Diversification may be especially important when prey species have multiple anti-predator strategies available, but these strategies conflict with each other. For example, rapid sprint speed and large size are both thought to decrease vulnerability to many predators. A physiological trade-off between swimming speed and growth rate has been documented in many aquatic species and, as a result, individual genotypes may employ one strategy or the other, but not both. Although rapid sprint speed is often assumed to decrease vulnerability to predators, this has only rarely been tested. Here I provide evidence that both rapid sprint speed and large size in tadpoles of the New Mexico spadefoot toad (Spea multiplicata) decreases predation risk from carnivore morphs of its congener the Great Plains spadefoot toad (Spea bombifrons). Such conflicts, coupled with spatio-temporal variation in predation pressure, may be important in maintaining genetic variation for trade-offs.

  20. Acute toxicity of arsenic and oxidative stress responses in the embryonic development of the common South American toad Rhinella arenarum.

    Science.gov (United States)

    Mardirosian, Mariana Noelia; Lascano, Cecilia Inés; Ferrari, Ana; Bongiovanni, Guillermina Azucena; Venturino, Andrés

    2015-05-01

    Arsenic (As), a natural element of ecological relevance, is found in natural water sources throughout Argentina in concentrations between 0.01 mg/L and 15 mg/L. The autochthonous toad Rhinella arenarum was selected to study the acute toxicity of As and the biochemical responses elicited by the exposure to As in water during its embryonic development. The median lethal concentration (LC50) value averaged 24.3 mg/L As and remained constant along the embryonic development. However, As toxicity drastically decreased when embryos were exposed from heartbeat-stage on day 4 of development, suggesting the onset of detoxification mechanisms. Given the environmental concentrations of As in Argentina, there is a probability of exceeding lethal levels at 1% of sites. Arsenic at sublethal concentrations caused a significant decrease in the total antioxidant potential but generated an increase in endogenous glutathione (GSH) content and glutathione S-transferase (GST) activity. This protective response might prevent a deeper decline in the antioxidant system and further oxidative damage. Alternatively, it might be linked to As conjugation with GSH for its excretion. The authors conclude that toad embryos are more sensitive to As during early developmental stages and that relatively high concentrations of this toxic element are required to elicit mortality, but oxidative stress may be an adverse effect at sublethal concentrations.

  1. MEASUREMENT OF REGIONAL BONE BLOOD FLOW IN THE CANINE MANDIBULAR RAMUS USING RADIOLABELLED TOAD RED BLOOD CELLS

    Institute of Scientific and Technical Information of China (English)

    毛驰; 王翰章

    1994-01-01

    Toad red blood cells were used to measure regional bone blood flow in the canine mandibular ramus.The blood cells were labelled with sodium pertechnetate and fixed in 10% formalin;they were 22×15 μm in size and had a specific gravity close to that of dog red blood cells.These cells had no discernible effect on systemic hemody-namics after injection,did not agglutinate,were well mixed and evenly distributed throughout the body,and were completely extracted in one circulation through the mandible.The mandibular ramus was divided into six regions,and the blood flow rates in each were found to be similar to those reported in previous studies with radiolabelled carbonized,microspheres.Furthermore,the blood flow distribution pattern of the mandibular ramus determined in this study was identical to that of our previous study using the bone-seeking radionuclide method.We suggest that radiolabelled toad red blood cells are an ideal marker for measuring regional blood flow in the canine mandible.

  2. Cyclic AMP-and beta-agonist-activated chloride conductance of a toad skin epithelium.

    Science.gov (United States)

    Willumsen, N J; Vestergaard, L; Larsen, E H

    1992-04-01

    1. The control by intracellular cyclic AMP and beta-adrenergic stimulation of chloride conductance was studied in toad skin epithelium mounted in a chamber on the stage of an upright microscope. Impalement of identified principal cells from the serosal side with single-barrelled conventional or double-barrelled Cl(-)-sensitive microelectrodes was performed at x500 magnification. For blocking the active sodium current 50 microM-amiloride was present in the mucosal bath. 2. When clamped at transepithelial potential difference V = 0 mV, the preparations generated clamping currents of 0.9 +/- 1 microA/cm2 (mean +/- S.E.M.; number of observations n = 55). The intracellular potential of principal cells (Vb) was -96 +/- 2 mV with a fractional resistance of the basolateral membrane (fRb) of 0.016 +/- 0.003 (n = 54), and an intracellular Cl- activity of 40 +/- 2 mM (n = 24). 3. At V = 0 mV, serosal application of a cyclic AMP analogue, dibutyryl cyclic AMP (500 microM) or a beta-adrenergic agonist, isoprenaline (5 microM) resulted in a sixfold increase in transepithelial Cl- conductance identified by standard 36Cl- tracer technique. 4. The clamping current at V = 0 mV was unaffected by cyclic AMP (short-circuit current Isc = 0.1 +/- 0.3 microA/cm2, n = 16) indicating that subepidermal Cl(-)-secreting glands are not functioning in our preparations obtained by collagenase treatment. 5. Cyclic AMP- or isoprenaline-induced chloride conductance (Gcl) activation (V = 0 mV) was not reflected in membrane potential and intracellular Cl- activity in principal cells. Intracellular chloride activity was constant at approximately 40 mM at membrane potentials between -90 and -100 mV. Therefore, it can be concluded that the principal cells are not contributing to activated Cl- currents. 6. At V = -100 mV where the voltage-dependent chloride conductance of mitochondria-rich (MR) cells was already fully activated, GCl was unaffected by cyclic AMP or isoprenaline. The major effect of these

  3. A Mathematical Model of Solute Coupled Water Transport in Toad Intestine Incorporating Recirculation of the Actively Transported Solute

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Sørensen, Jakob Balslev; Sørensen, Jens Nørkær

    2000-01-01

    those of tight junction and interspace basement membrane by convection-diffusion. With solute permeability of paracellular pathway large relative to paracellular water flow, the paracellular flux ratio of the solute (influx/outflux) is small (2-4) in agreement with experiments. The virtual solute...... back into lis, i.e., the solute would have to be recirculated. With input variables from toad intestine (Nedergaard, S., E.H. Larsen, and H.H. Ussing, J. Membr. Biol. 168:241-251), computations predict that 60-80% of the pumped flux stems from serosal bath in agreement with the experimental estimate...... of the recirculation flux. Robust solutions are obtained with realistic concentrations and pressures of lis, and with the following features. Rate of fluid absorption is governed by the solute permeability of mucosal membrane. Maximum fluid flow is governed by density of pumps on lis-membranes. Energetic efficiency...

  4. Relation between chloride exchange diffusion and a conductive chloride pathway across the isolated skin of the toad (Bufo bufo)

    DEFF Research Database (Denmark)

    Kristensen, P; Larsen, Erik Hviid

    1978-01-01

    Substitution of chloride in the outside bathing medium of the toad skin with bromide, iodide, nitrate and sulphate leads to a reduction in the apparent exchange diffusion of chloride across this tissue, and also to a reduction of the chloride current recorded during hyperpolarization. A series...... of inhibitors (thiocyanate, furosemide, phloretin, and acetazolamide) also affects chloride exchange diffusion, hyperpolarization current as well as chloride influx during hyperpolarization. Although in some cases, effects on the short circuit current were also observed none of the effects on chloride transport....... On the basis of these findings, and the results reported in the previous paper (Hviid Larsen and Kristensen 1977) it is considered probable that the membrane molecules responsible to chloride exchange diffusion under short circuit conditions, are rearranged under the influence of a hyperpolarizing clamping...

  5. A new species of Paracapillaria (Nematoda: Capillariidae) from the intestine of the toad Duttaphrynus melanostictus (Anura) from the Malayan Peninsula.

    Science.gov (United States)

    Moravec, Frantisek; Modrý, David; Jirků, Miloslav

    2007-08-01

    A new species of parasitic nematode, Paracapillaria malayensis n. sp. (Capillariidae), is described from the small intestine of the toad Duttaphrynus melanostictus imported from the Malayan Peninsula to the Czech Republic. The new species differs from the only other congeneric species, Paracapillaria spratti, mainly in the shape and structure of the spicular proximal end (with a lobular rim), smaller eggs (45-51 x 21-24 microm), longer spicule (336 microm), and the number (37-38) of stichocytes in gravid females; whereas P. spratti parasitizes frogs of the Microhylidae in Papua New Guinea, P. malayensis is a parasite of Bufonidae in the Malayan Peninsula. Other Paracapillaria spp. are parasites of fishes, birds, or mammals and they mostly differ from P. malayensis in the structure of eggs and some other morphological features. PMID:17918374

  6. Immunohistochemical localization of cathepsin D and a possible role of melanocytes during tail resorption in tadpoles of a tropical toad.

    Science.gov (United States)

    Mahapatra, Cuckoo; Mahapatra, Pravati Kumari

    2012-07-01

    Programmed cell death during anuran tail resorption is primarily brought about by apoptosis. Cathepsin D, a lysosomal aspartyl protease, is involved in the death of tail tissues. Thus, anuran tail resorption presents an ideal model to study cathepsin-mediated cell death during vertebrate development. Present study describes the trend of specific activity of cathepsin D in the tail of different developmental stages and immunohistochemical localization of cathepsin D in the tail tissues of the common Asian toad, Duttaphrynus melanostictus. Cathepsin D was involved in programmed cell death in epidermis, muscle, spinal cord, and blood cells in the resorbing tail. Interestingly, it was also involved in the pre-resorbing tail before visible tail resorption which indicates initiation of cell death even before actually the tail resorbs. Melanocytes were found to be one of the causative agents in degrading tail tissues and were associated with the degradation of muscle, epidermis and spinal cord of the resorbing tail. PMID:22505219

  7. Cadmium-induced toxicity on larvae of the common Asian toad Duttaphrynus melanostictus (Schneider 1799): evidence from empirical trials.

    Science.gov (United States)

    Ranatunge, R A A R; Wijesinghe, M R; Ratnasooriya, W D; Dharmarathne, H A S G; Wijesekera, R D

    2012-07-01

    This paper investigates the toxicity of cadmium (Cd) on young stages of the common Asian toad Duttaphrynus melanostictus (Schneider 1799). Signs of acute toxicity were evident in tadpoles repeatedly exposed to five concentrations ranging from 0.002 to 2 mg L(-1)of Cd which included environmentally relevant levels. Mortality at concentrations of 0.02 mg L(-1) and above was enhanced from 2 % at 0.02 mg L(-1) to 100 % at 1 mg L(-1), in a dose-dependent manner. Significant growth impairment was evident at 0.20 mg L(-1) with the larvae being markedly smaller. Delayed metamorphosis and retarded swimming were also observed. Therefore levels of Cd recorded in some freshwater bodies in Sri Lanka (e.g. 0.2 mg L(-1)) may be detrimental to the young stages of D. melanostictus. PMID:22526988

  8. Checklist and Simple Identification Key for Frogs and Toads from District IV of The MADA Scheme, Kedah, Malaysia.

    Science.gov (United States)

    Jaafar, Ibrahim; Chai, Teoh Chia; Sah, Shahrul Anuar Mohd; Akil, Mohd Abdul Muin Md

    2009-12-01

    A survey was conducted to catalogue the diversity of anurans in District IV of the Muda Agriculture Development Authority Scheme (MADA) in Kedah Darul Aman, Malaysia, from July 1996 to January 1997. Eight species of anurans from three families were present in the study area. Of these, the Common Grass Frog (Fejevarya limnocharis) was the most abundant, followed by Mangrove Frog (Fejevarya cancrivora), Long-legged Frog (Hylarana macrodactyla), and Common Toad (Duttaphrynus melanostictus). Puddle Frog (Occidozyga lima), Taiwanese Giant Frog (Hoplobatrachus rugulosus), and Banded Bullfrog (Kaluola pulchra) were rare during the sampling period, and only one Paddy Frog (Hylarana erythraea) was captured. A simple identification key for the anurans of this area is included for use by scientists and laymen alike. PMID:24575178

  9. Sexual selection in cane toads Rhinella marina: A male’s body size affects his success and his tactics

    Directory of Open Access Journals (Sweden)

    Haley BOWCOCK, Gregory P. BROWN, Richard SHINE

    2013-12-01

    Full Text Available Male body size can play an important role in the mating systems of anuran amphibians. We conducted laboratory-based trials with cane toads Rhinella (Bufo marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male's body size on his reproductive success and behavior (mate choice. Males were stimulated with a synthetic hormone to induce reproductive readiness. Larger body size enhanced a male toad's ability to displace a smaller rival from amplexus, apparently because of physical strength: more force was required to dislodge a larger than a smaller amplectant male. A male’s body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size preference was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs: males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex identification (one of the individuals involved is almost certainly a female. Thus, a male cane toad’s body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs [Current Zoology 59 (6: 747–753, 2013].

  10. Changes of body fluid and hematology in toad and their rehabilitation following intermittent exposure to simulated high altitude

    Science.gov (United States)

    Biswas, H. M.; Boral, M. C.

    1986-06-01

    Three groups of adult male toads were exposed intermittently in a decompression chamber for a daily period of 4 and 8 hours at a time for 6 consecutive days to an “altitude” of 12,000; 18,000 and 24,000 feet (3658; 5486; 7315 m) respectively. Most of the exposed animals were sacrificed immediately after the last exposure, but only a few animals experiencing 8 hours of exposure were sacrificed after a further 16 hours of exposure at normal atmospheric pressure. Eight hours of daily exposure for 6 days causes a decrease of body fluids and an increase of hematological parameters in all the altitude exposed animals compared with to the changes noted in the animals having 4 hours of daily exposure for 6 days at the same altitude levels. The animals that were exposed to pressures equivalent to altitudes of 12,000 and 18,000 feet daily for 8 hours were found to return nearly to their normal body fluids and hematological balance after 16 hours of exposure to normal atmospheric pressure, whereas the animals exposed for a similar period at an equivalent 24,000 feet failed to get back their normal balance of body fluids and hematology after 16 hours of exposure at normal atmospheric pressure. The present experiment shows that the body weight loss and changes of body fluid and hematological parameters in the toad after exposure to simulated high altitude are due not only to dehydration, but suggest that hypoxia may also have a role.

  11. Effects of a glyphosate-based herbicide on the development of Common toads (Bufo bufo L.; Amphibia) at different temperatures

    Science.gov (United States)

    Baier, Fabian; Gruber, Edith; Spangl, Bernhard; Zaller, Johann G.

    2016-04-01

    Herbicides based on the active ingredient glyphosate are frequently applied in agriculture, horticulture and private gardens all over the world. Recently, leaching of glyphosate or its metabolite (AMPA) into water bodies inhabited by amphibians has been reported. However, very little is known about non-target effects of these herbicides on amphibians and even less is known to what extent different temperatures might alter these effects. Using climate chambers, we investigated the effects of the glyphosate-based herbicide Roundup PowerFlex® (480 g L-1 glyphosate, formulated as 588 g L-1 potassium salt) on the larval development of Common toads (Bufo bufo L.; Amphibia: Anura) under different temperature regimes (15°C vs. 20°C). We established five herbicide concentrations: 0, 1.5, 3, 4 mg acid equivalent L-1 and a 4 mg a.e. L-1 pulse treatment (totally three applications of 1.5, 1.5 and another 1 mg a.e. L-1) at each temperature in a full-factorial design. Each treatment combination was replicated five times, the experiment ran for 24 days. Results showed a highly significant effect of temperature on body length and body width but no effect of herbicide concentration on these growth parameters. Moreover, highly significant interactions between herbicide and temperature on body length and body width were observed suggesting that herbicides had different effects on different temperatures. In conclusion, although Roundup PowerFlex® at the tested concentrations appeared to have no acute toxicity to larvae of Common toads, the observed effects on tadpole morphology will potentially affect competitive interactions in spawning ponds of amphibia. Our findings of herbicide x temperature interactions might become more prevalent when human-induced climate change will lead to more extreme temperatures.

  12. Aerobic scope and cardiovascular oxygen transport is not compromised at high temperatures in the toad Rhinella marina.

    Science.gov (United States)

    Overgaard, Johannes; Andersen, Jonas L; Findsen, Anders; Pedersen, Pil B M; Hansen, Kasper; Ozolina, Karlina; Wang, Tobias

    2012-10-15

    Numerous recent studies convincingly correlate the upper thermal tolerance limit of aquatic ectothermic animals to reduced aerobic scope, and ascribe the decline in aerobic scope to failure of the cardiovascular system at high temperatures. In the present study we investigate whether this 'aerobic scope model' applies to an air-breathing and semi-terrestrial vertebrate Rhinella marina (formerly Bufo marinus). To quantify aerobic scope, we measured resting and maximal rate of oxygen consumption at temperatures ranging from 10 to 40°C. To include potential effects of acclimation, three groups of toads were acclimated chronically at 20, 25 and 30°C, respectively. The absolute difference between resting and maximal rate of oxygen consumption increased progressively with temperature and there was no significant decrease in aerobic scope, even at temperature immediately below the lethal limit (41-42°C). Haematological and cardiorespiratory variables were measured at rest and immediately after maximal activity at benign (30°C) and critically high (40°C) temperatures. Within this temperature interval, both resting and active heart rate increased, and there was no indication of respiratory failure, judged from high arterial oxygen saturation, P(O2) and [Hb(O2)]. With the exception of elevated resting metabolic rate for cold-acclimated toads, we found few differences in the thermal responses between acclimation groups with regard to the cardiometabolic parameters. In conclusion, we found no evidence for temperature-induced cardiorespiratory failure in R. marina, indicating that maintenance of aerobic scope and oxygen transport is unrelated to the upper thermal limit of this air-breathing semi-terrestrial vertebrate.

  13. Toad radiation reveals into-India dispersal as a source of endemism in the Western Ghats-Sri Lanka biodiversity hotspot

    Directory of Open Access Journals (Sweden)

    Bossuyt Franky

    2009-06-01

    Full Text Available Abstract Background High taxonomic level endemism in the Western Ghats-Sri Lanka biodiversity hotspot has been typically attributed to the subcontinent's geological history of long-term isolation. Subsequent out of – and into India dispersal of species after accretion to the Eurasian mainland is therefore often seen as a biogeographic factor that 'diluted' the composition of previously isolated Indian biota. However, few molecular studies have focussed on into-India dispersal as a possible source of endemism on the subcontinent. Using c. 6000 base pairs of mitochondrial and nuclear DNA, we investigated the evolutionary history and biogeography of true toads (Bufonidae, a group that colonized the Indian Subcontinent after the Indo-Asia collision. Results Contrary to previous studies, Old World toads were recovered as a nested clade within New World Bufonidae, indicating a single colonization event. Species currently classified as Ansonia and Pedostibes were both recovered as being non-monophyletic, providing evidence for the independent origin of torrential and arboreal ecomorphs on the Indian subcontinent and in South-East Asia. Our analyses also revealed a previously unrecognized adaptive radiation of toads containing a variety of larval and adult ecomorphs. Molecular dating estimates and biogeographic analyses indicate that the early diversification of this clade happened in the Western Ghats and Sri Lanka during the Late Oligocene to Early Miocene. Conclusion Paleoclimate reconstructions have shown that the Early Neogene of India was marked by major environmental changes, with the transition from a zonal- to the current monsoon-dominated climate. After arrival in the Western Ghats-Sri Lanka hotspot, toads diversified in situ, with only one lineage able to successfully disperse out of these mountains. Consequently, higher taxonomic level endemism on the Indian Subcontinent is not only the result of Cretaceous isolation, but also of invasion

  14. Volunteer Conservation Action Data Reveals Large-Scale and Long-Term Negative Population Trends of a Widespread Amphibian, the Common Toad (Bufo bufo)

    Science.gov (United States)

    Petrovan, Silviu O.

    2016-01-01

    Rare and threatened species are the most frequent focus of conservation science and action. With the ongoing shift from single-species conservation towards the preservation of ecosystem services, there is a greater need to understand abundance trends of common species because declines in common species can disproportionately impact ecosystems function. We used volunteer-collected data in two European countries, the United Kingdom (UK) and Switzerland, since the 1970s to assess national and regional trends for one of Europe’s most abundant amphibian species, the common toad (Bufo bufo). Millions of toads were moved by volunteers across roads during this period in an effort to protect them from road traffic. For Switzerland, we additionally estimated trends for the common frog (Rana temporaria), a similarly widespread and common amphibian species. We used state-space models to account for variability in detection and effort and included only populations with at least 5 years of data; 153 populations for the UK and 141 for Switzerland. Common toads declined continuously in each decade in both countries since the 1980s. Given the declines, this common species almost qualifies for International Union for the Conservation of Nature (IUCN) red-listing over this period despite volunteer conservation efforts. Reasons for the declines and wider impacts remain unknown. By contrast, common frog populations were stable or increasing in Switzerland, although there was evidence of declines after 2003. “Toads on Roads” schemes are vital citizen conservation action projects, and the data from such projects can be used for large scale trend estimations of widespread amphibians. We highlight the need for increased research into the status of common amphibian species in addition to conservation efforts focusing on rare and threatened species. PMID:27706154

  15. Polyphyly of Asian Tree Toads, Genus Pedostibes Günther, 1876 (Anura: Bufonidae), and the Description of a New Genus from Southeast Asia

    OpenAIRE

    Kin Onn Chan; L Lee Grismer; Anil Zachariah; Brown, Rafe M.; Robin Kurian Abraham

    2016-01-01

    The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primari...

  16. Role of the endogenous kallikrein-kinin system in modulating vasopressin-stimulated water flow and urea permeability in the toad urinary bladder.

    OpenAIRE

    Carvounis, C P; Carvounis, G; Arbeit, L A

    1981-01-01

    This study investigates the endogenous kallikrein-kinin system's role as a modulator of vasopressin action in the toad urinary bladder. Kalli-krein inhibition by aprotinin, which results in decreased kinin production, significantly increased both vasopressin and 8-Br-cyclic (c) AMP-stimulated water flow. Kinin potentiation by the kininase II inhibitor captopril (SQ 14225) significantly decreased vasopressin and 8-Br-cAMP-stimulated water flow. In contrast to water flow, vasopressin-stimulated...

  17. Intoxicación aguda en perro por toxinas de sapo (Bufo bufo - Acute intoxication in a dog by toxins of a toad (Bufo bufo

    Directory of Open Access Journals (Sweden)

    Fernández-Palacios, O´Connor, Rocío

    2009-04-01

    Full Text Available ResumenLas intoxicaciones por toxinas de sapo no son frecuentes en España y su incidencia es mayor en primavera y verano. En este trabajo describimos un caso de intoxicación aguda de una perra de 4 años de edad tras la aprehensión de un sapo (Bufo bufo en la zona de Huelva. Los signos de una intoxicación comenzaron a los 15 minutos de entrar en contacto con el sapo muriendo a las 3 horas sin responder al tratamiento suministrado (corticoides, atropina, fluidoterapia y acepromazina. Aunque el diagnóstico fue precoz, a pesar del tratamiento se produjo la muerte en 3 horas.SummaryIntoxications by toad toxins are not frequent in Spain, and its incidence is greater in spring and summer. In this work it is described a case of an acute intoxication of a dog of 4 years old by toad toxins (Bufo bufo in the area of Huelva. The animal began to show signs of intoxication 15 minutes after the contact with the toad, dying 3 hours later without any response to the provided treatment (corticoids, atropine, fluidotherapy and acepromazine. Although the diagnosis was precocious and the treatment was administrated, after 3 hours the animal died.

  18. Polyphyly of Asian Tree Toads, Genus Pedostibes Günther, 1876 (Anura: Bufonidae), and the Description of a New Genus from Southeast Asia.

    Science.gov (United States)

    Chan, Kin Onn; Grismer, L Lee; Zachariah, Anil; Brown, Rafe M; Abraham, Robin Kurian

    2016-01-01

    The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primarily South Asian clade of toads, containing the genera Adenomus, Xanthophryne, and Duttaphrynus. Southeast Asian Pedostibes on the other hand, are nested within a Southeast Asian clade, which is the sister lineage to the Southeast Asian river toad genus Phrynoidis. We demonstrate that Indian and Southeast Asian Pedostibes are not only allopatric and polyphyletic, but also exhibit significant differences in morphology and reproductive mode, indicating that the Southeast Asian species' are not congeneric with the true Pedostibes of India. As a taxonomic solution, we describe a new genus, Rentapia gen. nov. to accommodate the Southeast Asian species.

  19. Polyphyly of Asian Tree Toads, Genus Pedostibes Günther, 1876 (Anura: Bufonidae), and the Description of a New Genus from Southeast Asia.

    Science.gov (United States)

    Chan, Kin Onn; Grismer, L Lee; Zachariah, Anil; Brown, Rafe M; Abraham, Robin Kurian

    2016-01-01

    The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primarily South Asian clade of toads, containing the genera Adenomus, Xanthophryne, and Duttaphrynus. Southeast Asian Pedostibes on the other hand, are nested within a Southeast Asian clade, which is the sister lineage to the Southeast Asian river toad genus Phrynoidis. We demonstrate that Indian and Southeast Asian Pedostibes are not only allopatric and polyphyletic, but also exhibit significant differences in morphology and reproductive mode, indicating that the Southeast Asian species' are not congeneric with the true Pedostibes of India. As a taxonomic solution, we describe a new genus, Rentapia gen. nov. to accommodate the Southeast Asian species. PMID:26788854

  20. Polyphyly of Asian Tree Toads, Genus Pedostibes Gunther, 1876 (Anura: Bufonidae, and the Description of a New Genus from Southeast Asia.

    Directory of Open Access Journals (Sweden)

    Kin Onn Chan

    Full Text Available The Asian Tree Toad genus Pedostibes, as currently understood, exhibits a conspicuously disjunct distribution, posing several immediate questions relating to the biogeography and taxonomy of this poorly known group. The type species, P. tuberculosus and P. kempi, are known only from India, whereas P. hosii, P. rugosus, and P. everetti are restricted to Southeast Asia. Several studies have shown that these allopatric groups are polyphyletic, with the Indian Pedostibes embedded within a primarily South Asian clade of toads, containing the genera Adenomus, Xanthophryne, and Duttaphrynus. Southeast Asian Pedostibes on the other hand, are nested within a Southeast Asian clade, which is the sister lineage to the Southeast Asian river toad genus Phrynoidis. We demonstrate that Indian and Southeast Asian Pedostibes are not only allopatric and polyphyletic, but also exhibit significant differences in morphology and reproductive mode, indicating that the Southeast Asian species' are not congeneric with the true Pedostibes of India. As a taxonomic solution, we describe a new genus, Rentapia gen. nov. to accommodate the Southeast Asian species.

  1. Cytogenetic Analysis of the South American Fruit Fly Anastrepha fraterculus (Diptera:Tephritidae) Species Complex: Construction of Detailed Photographic Polytene Chromosome Maps of the Argentinian Af. sp.1 Member

    Science.gov (United States)

    Augustinos, Antonios A.; Drosopoulou, Elena; Lanzavecchia, Silvia B.; Cladera, Jorge L.; Caceres, Carlos; Bourtzis, Kostas; Mavragani-Tsipidou, Penelope; Zacharopoulou, Antigone

    2016-01-01

    Genetic and cytogenetic studies constitute a significant basis for understanding the biology of insect pests and the design and the construction of genetic tools for biological control strategies. Anastrepha fraterculus is an important pest of the Tephritidae family. It is distributed from southern Texas through eastern Mexico, Central America and South America causing significant crop damage and economic losses. Currently it is considered as a species complex; until now seven members have been described based on multidisciplinary approaches. Here we report the cytogenetic analysis of an Argentinian population characterized as Af. sp.1 member of the Anastrepha fraterculus species complex. The mitotic karyotype and the first detailed photographic maps of the salivary gland polytene chromosomes are presented. The mitotic metaphase complement consists of six (6) pairs of chromosomes, including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the salivary gland polytene complement shows a total number of five long chromosomes that correspond to the five autosomes of the mitotic karyotype and a heterochromatic network corresponding to the sex chromosomes. Comparison of the polytene chromosome maps between this species and Anastrepha ludens shows significant similarity. The polytene maps presented here are suitable for cytogenetic studies that could shed light on the species limits within this species complex and support the development of genetic tools for sterile insect technique (SIT) applications. PMID:27362546

  2. Cytogenetic Analysis of the South American Fruit Fly Anastrepha fraterculus (Diptera:Tephritidae) Species Complex: Construction of Detailed Photographic Polytene Chromosome Maps of the Argentinian Af. sp.1 Member.

    Science.gov (United States)

    Gariou-Papalexiou, Angeliki; Giardini, María Cecilia; Augustinos, Antonios A; Drosopoulou, Elena; Lanzavecchia, Silvia B; Cladera, Jorge L; Caceres, Carlos; Bourtzis, Kostas; Mavragani-Tsipidou, Penelope; Zacharopoulou, Antigone

    2016-01-01

    Genetic and cytogenetic studies constitute a significant basis for understanding the biology of insect pests and the design and the construction of genetic tools for biological control strategies. Anastrepha fraterculus is an important pest of the Tephritidae family. It is distributed from southern Texas through eastern Mexico, Central America and South America causing significant crop damage and economic losses. Currently it is considered as a species complex; until now seven members have been described based on multidisciplinary approaches. Here we report the cytogenetic analysis of an Argentinian population characterized as Af. sp.1 member of the Anastrepha fraterculus species complex. The mitotic karyotype and the first detailed photographic maps of the salivary gland polytene chromosomes are presented. The mitotic metaphase complement consists of six (6) pairs of chromosomes, including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the salivary gland polytene complement shows a total number of five long chromosomes that correspond to the five autosomes of the mitotic karyotype and a heterochromatic network corresponding to the sex chromosomes. Comparison of the polytene chromosome maps between this species and Anastrepha ludens shows significant similarity. The polytene maps presented here are suitable for cytogenetic studies that could shed light on the species limits within this species complex and support the development of genetic tools for sterile insect technique (SIT) applications. PMID:27362546

  3. Cytogenetic Analysis of the South American Fruit Fly Anastrepha fraterculus (Diptera:Tephritidae Species Complex: Construction of Detailed Photographic Polytene Chromosome Maps of the Argentinian Af. sp.1 Member.

    Directory of Open Access Journals (Sweden)

    Angeliki Gariou-Papalexiou

    Full Text Available Genetic and cytogenetic studies constitute a significant basis for understanding the biology of insect pests and the design and the construction of genetic tools for biological control strategies. Anastrepha fraterculus is an important pest of the Tephritidae family. It is distributed from southern Texas through eastern Mexico, Central America and South America causing significant crop damage and economic losses. Currently it is considered as a species complex; until now seven members have been described based on multidisciplinary approaches. Here we report the cytogenetic analysis of an Argentinian population characterized as Af. sp.1 member of the Anastrepha fraterculus species complex. The mitotic karyotype and the first detailed photographic maps of the salivary gland polytene chromosomes are presented. The mitotic metaphase complement consists of six (6 pairs of chromosomes, including one pair of heteromorphic sex chromosomes, with the male being the heterogametic sex. The analysis of the salivary gland polytene complement shows a total number of five long chromosomes that correspond to the five autosomes of the mitotic karyotype and a heterochromatic network corresponding to the sex chromosomes. Comparison of the polytene chromosome maps between this species and Anastrepha ludens shows significant similarity. The polytene maps presented here are suitable for cytogenetic studies that could shed light on the species limits within this species complex and support the development of genetic tools for sterile insect technique (SIT applications.

  4. Variation in Chemical Defense Among Natural Populations of Common Toad, Bufo bufo, Tadpoles: the Role of Environmental Factors.

    Science.gov (United States)

    Bókony, Veronika; Móricz, Ágnes M; Tóth, Zsófia; Gál, Zoltán; Kurali, Anikó; Mikó, Zsanett; Pásztor, Katalin; Szederkényi, Márk; Tóth, Zoltán; Ujszegi, János; Üveges, Bálint; Krüzselyi, Dániel; Capon, Robert J; Hoi, Herbert; Hettyey, Attila

    2016-04-01

    Defensive toxins are widespread in nature, yet we know little about how various environmental factors shape the evolution of chemical defense, especially in vertebrates. In this study we investigated the natural variation in the amount and composition of bufadienolide toxins, and the relative importance of ecological factors in predicting that variation, in larvae of the common toad, Bufo bufo, an amphibian that produces toxins de novo. We found that tadpoles' toxin content varied markedly among populations, and the number of compounds per tadpole also differed between two geographical regions. The most consistent predictor of toxicity was the strength of competition, indicating that tadpoles produced more compounds and larger amounts of toxins when coexisting with more competitors. Additionally, tadpoles tended to contain larger concentrations of bufadienolides in ponds that were less prone to desiccation, suggesting that the costs of toxin production can only be afforded by tadpoles that do not need to drastically speed up their development. Interestingly, this trade-off was not alleviated by higher food abundance, as periphyton biomass had negligible effect on chemical defense. Even more surprisingly, we found no evidence that higher predation risk enhances chemical defenses, suggesting that low predictability of predation risk and high mortality cost of low toxicity might select for constitutive expression of chemical defense irrespective of the actual level of predation risk. Our findings highlight that the variation in chemical defense may be influenced by environmental heterogeneity in both the need for, and constraints on, toxicity as predicted by optimal defense theory. PMID:27059330

  5. Feeding pattern and use of reproductive habitat of the Striped toad Rhinella crucifer (Anura: Bufonidae from Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo B. Ferreira

    2009-12-01

    Full Text Available Diet composition, foraging mode, and using of reproductive habitat of Rhinella crucifer was studied in an artificial pond in Espírito Santo, Brazil. The favored substrate was leaf litter, followed by Cyperaceae/Poaceae. Calling sites, preferred for 23.3 % (n = 7 of the observed toads, were within the water, with only the head not submerged. We analyzed a total of 61 specimens, mainly males (98.5% male and 1.5% female. Seven categories of prey were found in the stomach contents: Coleoptera, Hymenoptera (Formicidae, Isoptera, Lepidoptera, Orthoptera, Gastropoda (Mollusca, Opilionida (Arachnida. Our studies indicate that the diet of Rhinella crucifer consists mainly of terrestrial colonial arthropods. Formicidae was the predominant food item in frequency of occurrence, number of prey and weight. Isoptera and Coleoptera were also relevant in terms of weight. Neither large ontogenetic dietary nor seasonal shifts were observed in the population studied. Our results suggest that no intraspecific food resource partitioning occurs in adult or juveniles. Rhinella crucifer adults avoid competition inhabiting different home range habitats and seem to be ant-specialist with a wide foraging mode.

  6. Exposure of toad embryos and larvae to pesticides. Use of nuclear technique to determine their effect on the reproduction, survival and potential risk to Bufo arenarum populations

    International Nuclear Information System (INIS)

    Application of pesticides is currently the most common method used to control agricultural pests. However, undesired effects on non-target organisms and pollution of the soil, air and water are frequent consequences. Amphibians are good bioindicators of the presence of contaminants in the environment, because they are semi-aquatic animals located at the top of the food chain. In many parts of the world, amphibian populations are declining, and many reasons have been suggested for these losses. Although a link between widespread decline and pesticide residues has yet to be established, it is suspected that contamination of their breeding sites with pesticide residues has had a deleterious effect on the reproduction and development of amphibians. Recent experiments with a widely distributed toad, Bufo arenarum Hensel, in South America, particularly in Argentina, indicate that a variety of insecticides affects the fertilization process through the activation of an enzyme that degrades the source of second messengers and is involved in transducing the sperm signal to the oocyte. This harmful effect is not restricted to the fertilization process, since embryonic and larval development are also affected, producing severe morphological and behavioural abnormalities in embryos. Embryonic and larval development influence the timing of metamorphosis, the susceptibility to predation, survival in the terrestrial environment, and even the success of future reproduction, these being the most sensitive period of a toad's life. Evaluation of the pesticides in our region showed their presence in many of the potential breeding sites, confirming that they may influence the survival of toad populations. (author). 18 refs, 1 fig., 1 tab

  7. A comparison of human chorionic gonadotropin and luteinizing hormone releasing hormone on the induction of spermiation and amplexus in the American toad (Anaxyrus americanus

    Directory of Open Access Journals (Sweden)

    Kouba Andrew J

    2012-08-01

    Full Text Available Abstract Background Captive breeding programs for endangered amphibian species often utilize exogenous hormones for species that are difficult to breed. The purpose of our study was to compare the efficacy of two different hormones at various concentrations on sperm production, quantity and quality over time in order to optimize assisted breeding. Methods Male American toads (Anaxyrus americanus were divided into three separate treatment groups, with animals in each group rotated through different concentrations of luteinizing hormone releasing hormone analog (LHRH; 0.1, 1.0, 4.0 and 32 micrograms/toad, human chorionic gonadotropin (hCG; 50, 100, 200, and 300 IU, or the control over 24 hours. We evaluated the number of males that respond by producing spermic urine, the sperm concentration, percent motility, and quality of forward progression. We also evaluated the effects of hCG and LHRH on reproductive behavior as assessed by amplexus. Data were analyzed using the Generalized Estimating Equations incorporating repeated measures over time and including the main effects of treatment and time, and the treatment by time interaction. Results The hormone hCG was significantly more effective at stimulating spermiation in male Anaxyrus americanus than LHRH and showed a dose-dependent response in the number of animals producing sperm. At the most effective hCG dose (300 IU, 100% of the male toads produced sperm, compared to only 35% for the best LHRH dose tested (4.0 micrograms. In addition to having a greater number of responders (P  Conclusion There is a clear dichotomy between the two hormones’ physiological responses on gamete production and stimulation of amplexus. Understanding how these two hormones influence physiology and reproductive behaviors in amphibians will have direct bearing on establishing similar breeding protocols for endangered species.

  8. Effects of landscape composition and wetland fragmentation on frog and toad abundance and species richness in Iowa and Wisconsin, USA [abstract

    Science.gov (United States)

    Knutson, M.G.; Sauer, J.R.; Olsen, D.A.; Mossman, M.J.; Hemesath, L.M.; Lannoo, M.J.

    1998-01-01

    We examined the relationships between anuran diversity and landscape features in the Upper Midwestern United States. Anuran relative abundance and species richness were measured using data collected by Wisconsin and Iowa state calling surveys conducted from 1990-1995. Landscape features surrounding survey points were determined using National Wetland Inventory and Wisconsin Wetland Inventory maps. We tested several hypotheses suggested by the literature. We hypothesized that the relative abundance and species richness of anurans that breed in ephemeral wetlands is positively correlated with the surrounding area of temporary wetlands and emergent wetlands. We hypothesized that the relative abundance and species richness of anurans is positively correlated with patch diversity and wetland edges, in the absence of local fragmentation effects. We hypothesized that the relative abundance and species richness of anurans is positively associated with forests but negatively associated with agriculture and urban areas. Our results show that the interspersion of different wetland types and the concomitant increase in wetland edge habitats were generally positive for frogs and toads and anuran abundance and diversity were generally higher in association with forests, especially forested wetlands. The presence of agriculture did not always depress frog and toad populations or diversity; some species were associated with agricultural landscapes. The two states differed in how anurans were associated with landscape features like lakes and permanent wetlands. We found that frog and toad relative abundance and diversity were lower when urban areas were present. Managers can use models like ours, generated from landscape analyses, along with range maps and population trend analyses to get a comprehensive picture of the health of individual species and groups of species. Our models could be applied to the landscape as a whole, and used to predict species relative abundance and

  9. A Single Transcriptome of a Green Toad (Bufo viridis) Yields Candidate Genes for Sex Determination and -Differentiation and Non-Anonymous Population Genetic Markers.

    Science.gov (United States)

    Gerchen, Jörn F; Reichert, Samuel J; Röhr, Johannes T; Dieterich, Christoph; Kloas, Werner; Stöck, Matthias

    2016-01-01

    Large genome size, including immense repetitive and non-coding fractions, still present challenges for capacity, bioinformatics and thus affordability of whole genome sequencing in most amphibians. Here, we test the performance of a single transcriptome to understand whether it can provide a cost-efficient resource for species with large unknown genomes. Using RNA from six different tissues from a single Palearctic green toad (Bufo viridis) specimen and Hiseq2000, we obtained 22,5 Mio reads and publish >100,000 unigene sequences. To evaluate efficacy and quality, we first use this data to identify green toad specific candidate genes, known from other vertebrates for their role in sex determination and differentiation. Of a list of 37 genes, the transcriptome yielded 32 (87%), many of which providing the first such data for this non-model anuran species. However, for many of these genes, only fragments could be retrieved. In order to allow also applications to population genetics, we further used the transcriptome for the targeted development of 21 non-anonymous microsatellites and tested them in genetic families and backcrosses. Eleven markers were specifically developed to be located on the B. viridis sex chromosomes; for eight markers we can indeed demonstrate sex-specific transmission in genetic families. Depending on phylogenetic distance, several markers, which are sex-linked in green toads, show high cross-amplification success across the anuran phylogeny, involving nine systematic anuran families. Our data support the view that single transcriptome sequencing (based on multiple tissues) provides a reliable genomic resource and cost-efficient method for non-model amphibian species with large genome size and, despite limitations, should be considered as long as genome sequencing remains unaffordable for most species. PMID:27232626

  10. Ion transport mechanisms in the mesonephric collecting duct system of the toad Bufo bufo: microelectrode recordings from isolated and perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2004-01-01

    It is not clear how and whether terrestrial amphibians handle NaCl transport in the distal nephron. Therefore, we studied ion transport in isolated perfused collecting tubules and ducts from toad, Bufo bufo, by means of microelectrodes. No qualitative difference in basolateral cell membrane...... and amiloride application showed a small apical Na+ conductance. Arginine vasotocin depolarized Vbl. The small apical Na+ conductance indicates that the collecting duct system contributes little to NaCl reabsorption when compared to aquatic amphibians. In contrast, Vbl rapidly depolarized upon lowering of [Na...

  11. Post-Messinian evolutionary relationships across the Sicilian channel: Mitochondrial and nuclear markers link a new green toad from Sicily to African relatives

    Directory of Open Access Journals (Sweden)

    Lo Brutto Sabrina

    2008-02-01

    Full Text Available Abstract Background Little attention has been paid to the consequences of the last landbridge between Africa and Sicily on Mediterranean biogeography. Previous paleontological and scarce molecular data suggest possible faunal exchange later than the well-documented landbridge in the Messinian (5.3 My; however, a possible African origin of recent terrestrial Sicilian fauna has not been thoroughly tested with molecular methods. To gain insight into the phylogeography of the region, we examine two mitochondrial and two nuclear markers (one is a newly adapted intron marker in green toads (Bufo viridis subgroup across that sea barrier, the Strait of Sicily. Results Extensive sampling throughout the western Mediterranean and North Africa revealed a deep sister relationship between Sicilian (Bufo siculus n.sp. and African green toads (B. boulengeri on the mitochondrial and nuclear level. Divergence times estimated under a Bayesian-coalescence framework (mtDNA control region and 16S rRNA range from the Middle Pliocene (3.6 My to Pleistocene (0.16 My with an average (1.83 to 2.0 My around the Pliocene/Pleistocene boundary, suggesting possible land connections younger than the Messinian (5.3 My. We describe green toads from Sicily and some surrounding islands as a new endemic species (Bufo siculus. Bufo balearicus occurs on some western Mediterranean islands (Corsica, Sardinia, Mallorca, and Menorca and the Apennine Peninsula, and is well differentiated on the mitochondrial and nuclear level from B. siculus as well as from B. viridis (Laurenti, whose haplotype group reaches northeastern Italy, north of the Po River. Detection of Calabrian B. balearicus haplotypes in northeastern Sicily suggests recent invasion. Our data agree with paleogeographic and fossil data, which suggest long Plio-Pleistocene isolation of Sicily and episodic Pleistocene faunal exchange across the Strait of Messina. It remains unknown whether both species (B. balearicus, B. siculus

  12. Ontogeny of corticotropin-releasing factor effects on locomotion and foraging in the Western spadefoot toad (Spea hammondii).

    Science.gov (United States)

    Crespi, Erica J; Denver, Robert J

    2004-11-01

    We investigated the effects of corticotropin-releasing factor (CRF) and corticosterone (CORT) on foraging and locomotion in Western spadefoot toad (Spea hammondii) tadpoles and juveniles to assess the behavioral functions of these hormones throughout development. We administered intracerebroventricular injections of ovine CRF or CRF receptor antagonist alphahelical CRF((9-41)) to tadpoles and juveniles, and observed behavior within 1.5 h after injection. In both premetamorphic (Gosner stage 33) and prometamorphic (Gosner stages 35-37) tadpoles, CRF injections increased locomotion and decreased foraging. Injections of alphahelical CRF((9-41)) reduced locomotion but did not affect foraging in premetamorphic tadpoles, but dramatically increased foraging in prometamorphic tadpoles compared to both placebo and uninjected controls. Similarly, alphahelical CRF((9-41)) injections stimulated food intake and prey-catching behavior in juveniles. These results suggest that in later-staged amphibians, endogenous CRF secretion modulates feeding by exerting a suppressive effect on appetite. By contrast to the inhibitory effect of CRF, 3-h exposure to CORT (500 nM added to the aquarium water) stimulated foraging in prometamorphic tadpoles. These tadpoles also exhibited a CORT-mediated increase in foraging 6 h after CRF injection, which was associated with elevated whole-body CORT content and blocked by glucocorticoid receptor (GR) antagonist (RU486) injections. Thus, exogenous CRF influences locomotion and foraging in both pre- and prometamorphic tadpoles, but endogenous CRF secretion in relatively unstressed animals does not affect foraging until prometamorphic stages. Furthermore, the opposing actions of CRF and CORT on foraging suggest that they are important regulators of energy balance and food intake in amphibians throughout development.

  13. Climate change and the distribution of neotropical red-bellied toads (Melanophryniscus, Anura, Amphibia): how to prioritize species and populations?

    Science.gov (United States)

    Zank, Caroline; Becker, Fernando Gertum; Abadie, Michelle; Baldo, Diego; Maneyro, Raúl; Borges-Martins, Márcio

    2014-01-01

    We used species distribution modeling to investigate the potential effects of climate change on 24 species of Neotropical anurans of the genus Melanophryniscus. These toads are small, have limited mobility, and a high percentage are endangered or present restricted geographical distributions. We looked at the changes in the size of suitable climatic regions and in the numbers of known occurrence sites within the distribution limits of all species. We used the MaxEnt algorithm to project current and future suitable climatic areas (a consensus of IPCC scenarios A2a and B2a for 2020 and 2080) for each species. 40% of the species may lose over 50% of their potential distribution area by 2080, whereas 28% of species may lose less than 10%. Four species had over 40% of the currently known occurrence sites outside the predicted 2080 areas. The effect of climate change (decrease in climatic suitable areas) did not differ according to the present distribution area, major habitat type or phylogenetic group of the studied species. We used the estimated decrease in specific suitable climatic range to set a conservation priority rank for Melanophryniscus species. Four species were set to high conservation priority: M. montevidensis, (100% of its original suitable range and all known occurrence points potentially lost by 2080), M. sp.2, M. cambaraensis, and M. tumifrons. Three species (M. spectabilis, M. stelzneri, and M. sp.3) were set between high to intermediate priority (more than 60% decrease in area predicted by 2080); nine species were ranked as intermediate priority, while eight species were ranked as low conservation priority. We suggest that monitoring and conservation actions should be focused primarily on those species and populations that are likely to lose the largest area of suitable climate and the largest number of known populations in the short-term.

  14. Screening breeding sites of the common toad (Bufo bufo) in England and Wales for evidence of endocrine disrupting activity.

    Science.gov (United States)

    Pickford, Daniel B; Jones, Alexandra; Velez-Pelez, Alejandra; Orton, Frances; Iguchi, Taisen; Mitsui, Naoko; Tooi, Osamu

    2015-07-01

    Anuran amphibians are often present in agricultural landscapes and may therefore be exposed to chemicals in surface waters used for breeding. We used passive accumulation devices (SPMD and POCIS) to sample contaminants from nine breeding sites of the Common toad (Bufo bufo) across England and Wales, measuring endocrine activity of the extracts in a recombinant yeast androgen screen (YAS) and yeast estrogen screen (YES) and an in vitro vitellogenin induction screen in primary culture of Xenopus laevis hepatocytes. We also assessed hatching, growth, survival, and development in caged larvae in situ, and sampled metamorphs for gonadal histopathology. None of the SPMD extracts exhibited estrogen receptor or androgen receptor agonist activity, while POCIS extracts from two sites in west-central England exhibited concentration-dependent androgenic activity in the YAS. Three sites exhibited significant estrogenic activity in both the YES and the Xenopus hepatocyte. Hatching rates varied widely among sites, but there was no consistent correlation between hatching rate and intensity of agricultural activity, predicted concentrations of agrochemicals, or endocrine activity measured in YES/YAS assays. While a small number of intersex individuals were observed, their incidence could not be associated with predicted pesticide exposure or endocrine activitity measured in the in vitro screens. There were no significant differences in sex ratio, as determined by gonadal histomorphology among the study sites, and no significant correlation was observed between proportion of males and predicted exposure to agrochemicals. However, a negative correlation did become apparent in later sampling periods between proportion of males and estrogenic activity of the POCIS sample, as measured in the YES. Our results suggest that larval and adult amphibians may be exposed to endocrine disrupting chemicals in breeding ponds, albeit at low concentrations, and that chemical contaminants other than

  15. Thermal effects on the dynamics and motor control of ballistic prey capture in toads: maintaining high performance at low temperature.

    Science.gov (United States)

    Deban, Stephen M; Lappin, A Kristopher

    2011-04-15

    Temperature has a strong influence on biological rates, including the contractile rate properties of muscle and thereby the velocity, acceleration and power of muscle-powered movements. We hypothesized that the dynamics of movements powered by elastic recoil have a lower thermal dependence than muscle-powered movements. We examined the prey capture behavior of toads (Bufo terrestris) using high speed imaging and electromyography to compare the effects of body temperature (11-35°C) on the kinematics, dynamics and motor control of two types of movement: (1) ballistic mouth opening and tongue projection, which are powered by elastic recoil, and (2) non-ballistic prey transport, including tongue retraction and mouth closing, which are powered directly by muscle contraction. Over 11-25°C, temperature coefficients of ballistic mouth opening and tongue projection dynamics (Q(10) of 0.99-1.25) were not significantly different from 1.00 and were consistently lower than those of prey transport movements (Q(10) of 1.77-2.26), supporting our main hypothesis. The depressor mandibulae muscle, which is responsible for ballistic mouth opening and tongue projection via the recovery of elastic strain energy stored by the muscle prior to the onset of the movement, was activated earlier and for a longer duration at lower temperatures (Q(10) of 2.29-2.41), consistent with a slowing of its contractile rates. Muscle recruitment was unaffected by temperature, as revealed by the lack of thermal dependence in the intensity of activity of both the jaw depressor and jaw levator muscles (Q(10) of 0.754-1.12). Over the 20-35°C range, lower thermal dependence was found for the dynamics of non-elastic movements and the motor control of both elastic and non-elastic movements, in accord with a plateau of high performance found in other systems.

  16. Roles of external and cellular Cl- ions on the activation of an apical electrodiffusional Cl- pathway in toad skin.

    Science.gov (United States)

    Procopio, J; Lacaz-Vieira, F

    1990-07-01

    This study is concerned with the short-circuit current, Isc, responses of the Cl(-)-transporting cells of toad skin submitted to sudden changes of the external Cl- concentration, [Cl]o. Sudden changes of [Cl]o, carried out under apical membrane depolarization, allowed comparison of the roles of [Cl]o and [Cl]cell on the activation of the apical Cl- pathways. Equilibration of short-circuited skins symmetrically in K-Ringer's solutions of different Cl- concentrations permitted adjustment of [Cl]cell to different levels. For a given Cl- concentration (in the range of 11.7 to 117 mM) on both sides of a depolarized apical membrane, this structure exhibits a high Cl- permeability, P(Cl)apical. On the other hand, for the same range of [Cl]cell but with [Cl]o = 0, P(Cl)apical is reduced to negligible values. These observations indicate that when the apical membrane is depolarized P(Cl)apical is modulated by [Cl]o; in the absence of external Cl- ions, intracellular Cl- is not sufficient to activate P(Cl)apical. Computer simulation shows that the fast Cl- currents induced across the apical membrane by sudden shifts of [Cl]o from a control equilibrium value strictly follow the laws of electrodiffusion. For each experimental group, the computer-generated Isc versus [( Cl]cell - [Cl]o) curve which best fits the experimental data can only be obtained by a unique pair of P(Cl)apical and Rb (resistance of the basolateral membrane), thus allowing the calculation of these parameters. The electrodiffusional behavior of the net Cl- flux across the apical membrane supports the channel nature of the apical Cl- pathways in the Cl(-)-transporting cells. Cl- ions contribute significantly to the overall conductance of the basolateral membrane even in the presence of a high K concentration in the internal solution. PMID:1698229

  17. A network extension of species occupancy models in a patchy environment applied to the Yosemite toad (Anaxyrus canorus)

    Science.gov (United States)

    Berlow, Eric L.; Knapp, Roland A.; Ostoja, Steven M.; Williams, Richard J.; McKenny, Heather; Matchett, John R.; Guo, Qinghau; Fellers, Gary M.; Kleeman, Patrick; Brooks, Matthew L.; Joppa, Lucas

    2013-01-01

    A central challenge of conservation biology is using limited data to predict rare species occurrence and identify conservation areas that play a disproportionate role in regional persistence. Where species occupy discrete patches in a landscape, such predictions require data about environmental quality of individual patches and the connectivity among high quality patches. We present a novel extension to species occupancy modeling that blends traditionalpredictions of individual patch environmental quality with network analysis to estimate connectivity characteristics using limited survey data. We demonstrate this approach using environmental and geospatial attributes to predict observed occupancy patterns of the Yosemite toad (Anaxyrus (= Bufo) canorus) across >2,500 meadows in Yosemite National Park (USA). A. canorus, a Federal Proposed Species, breeds in shallow water associated with meadows. Our generalized linear model (GLM) accurately predicted ~84% of true presence-absence data on a subset of data withheld for testing. The predicted environmental quality of each meadow was iteratively ‘boosted’ by the quality of neighbors within dispersal distance. We used this park-wide meadow connectivity network to estimate the relative influence of an individual Meadow’s ‘environmental quality’ versus its ‘network quality’ to predict: a) clusters of high quality breeding meadows potentially linked by dispersal, b) breeding meadows with high environmental quality that are isolated from other such meadows, c) breeding meadows with lower environmental quality where long-term persistence may critically depend on the network neighborhood, and d) breeding meadows with the biggest impact on park-wide breeding patterns. Combined with targeted data on dispersal, genetics, disease, and other potential stressors, these results can guide designation of core conservation areas for A. canorus in Yosemite National Park.

  18. Mixed population genomics support for the central marginal hypothesis across the invasive range of the cane toad (Rhinella marina) in Australia.

    Science.gov (United States)

    Trumbo, Daryl R; Epstein, Brendan; Hohenlohe, Paul A; Alford, Ross A; Schwarzkopf, Lin; Storfer, Andrew

    2016-09-01

    Understanding factors that cause species' geographic range limits is a major focus in ecology and evolution. The central marginal hypothesis (CMH) predicts that species cannot adapt to conditions beyond current geographic range edges because genetic diversity decreases from core to edge due to smaller, more isolated edge populations. We employed a population genomics framework using 24 235-33 112 SNP loci to test major predictions of the CMH in the ongoing invasion of the cane toad (Rhinella marina) in Australia. Cane toad tissue samples were collected along broad-scale, core-to-edge transects across their invasive range. Geographic and ecological core areas were identified using GIS and habitat suitability indices from ecological niche modelling. Bayesian clustering analyses revealed three genetic clusters, in the northwest invasion-front region, northeast precipitation-limited region and southeast cold temperature-limited region. Core-to-edge patterns of genetic diversity and differentiation were consistent with the CMH in the southeast, but were not supported in the northeast and showed mixed support in the northwest. Results suggest cold temperatures are a likely contributor to southeastern range limits, consistent with CMH predictions. In the northeast and northwest, ecological processes consisting of a steep physiological barrier and ongoing invasion dynamics, respectively, are more likely explanations for population genomic patterns than the CMH. PMID:27393238

  19. Regulation of cyclic GMP metabolism in toad photoreceptors. Definition of the metabolic events subserving photoexcited and attenuated states.

    Science.gov (United States)

    Dawis, S M; Graeff, R M; Heyman, R A; Walseth, T F; Goldberg, N D

    1988-06-25

    Photoreceptor metabolism of cGMP and its regulation were characterized in isolated toad retinas by determining the intensity and time dependence of light-induced changes in the following metabolic parameters: cGMP hydrolytic flux determined by the rate of 18O incorporation from 18O-water into retinal guanine nucleotide alpha-phosphoryls; changes in the total (protein-bound and unbound) concentrations of the guanine nucleotide metabolic intermediates; and changes in the concentration of metabolic (unbound) GDP calculated from the fraction of the alpha-GDP that undergoes labeling with 18O. The latter is interpreted to reflect the state of the equilibrium between GDP- and GTP-complexed forms of G-protein. With narrow band 500 nm light that preferentially stimulates red rod photoreceptors, a range of intensities covering approximately 5 log units produced increases of over 10-fold in cGMP metabolic flux. However, the characteristics of the cGMP metabolic response over the first 2.5 log units of intensity are readily distinguishable from those at higher intensities which exhibit progressive attenuation by an intensity- and time-dependent process. Over the range of low intensities (0.6-3 log photons.micron-2.s-1) the metabolic response is characterized by 1) increases in cGMP hydrolytic flux of up to 8-fold as a logarithmic function of intensity of photic stimulation that are sustained for at least 200 s; 2) small increases or no change in the concentration of total cGMP; 3) large increases of up to 10-fold in the concentration of metabolically active GDP as a linear function of intensity with no significant change in the tissue concentrations of total GDP or GTP; and 4) amplification of the photosignal by the metabolism of approximately 10,000 molecules of cGMP per photoisomerization with the major site of amplification at the level of the interaction of bleached rhodopsin with G-protein.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Peptide IC-20, encoded by skin kininogen-1 of the European yellow-bellied toad, Bombina variegata, antagonizes bradykinin-induced arterial smooth muscle relaxation

    Directory of Open Access Journals (Sweden)

    Mu Yang

    2011-01-01

    Full Text Available Objectives: The objectives were to determine if the skin secretion of the European yellow-bellied toad (Bombina variegata, in common with other related species, contains a bradykinin inhibitor peptide and to isolate and structurally characterize this peptide. Materials and Methods: Lyophilized skin secretion obtained from this toad was subjected to reverse phase HPLC fractionation with subsequent bioassay of fractions for antagonism of the bradykinin activity using an isolated rat tail artery smooth muscle preparation. Subsequently, the primary structure of the peptide was established by a combination of microsequencing, mass spectroscopy, and molecular cloning, following which a synthetic replicate was chemically synthesised for bioassay. Results: A single peptide of molecular mass 2300.92 Da was resolved in HPLC fractions of skin secretion and its primary structure determined as IYNAIWP-KH-NK-KPGLL-. Database interrogation with this sequence indicated that this peptide was encoded by skin kininogen-1 previously cloned from B. variegata. The blank cycles were occupied by cysteinyl (C residues and the peptide was located toward the C-terminus of the skin kininogen, and flanked N-terminally by a classical -KR- propeptide convertase processing site. The peptide was named IC-20 in accordance (I = N-terminal isoleucine, C = C-terminal cysteine, 20 = number of residues. Like the natural peptide, its synthetic replicate displayed an antagonism of bradykinin-induced arterial smooth muscle relaxation. Conclusion: IC-20 represents a novel bradykinin antagonizing peptide from amphibian skin secretions and is the third such peptide found to be co-encoded with bradykinins within skin kininogens.

  1. Nacionalismo territorialista en textos escolares: representaciones de la Patagonia en la dictadura militar argentina (1966-1983 Territorialist nationalism in school textbooks: representations of Patagonia in Argentinian military dictatorship (1966-1983

    Directory of Open Access Journals (Sweden)

    Jesús Jaramillo

    2012-03-01

    . Recent investigations focusing on the reality at schools have emphasized the textbooks' importance in the construction of national identities, and also of identities of socio-cultural, socio-ethnical, and regional.This article starts from a historiographical inquiry about school textbooks with the intent of reconstructing the various discursive textual and iconographic accounts in which Patagonia was represented in the primary schools of the provinces of Río Negro and Neuquén during the Argentinian dictatorship periods of 1966-1973 and 1976-1983. In essence, a group of narratives about Patagonia and its inhabitants was brought forward based on three cores of meaning: that of the indigenous, uncultivated and desert territory; that of the promise of progress and tourism; and that of national sovereignty. We shall argue that nationwide school textbooks of eminently political, but also ethnical and racial, slants became means of formation and, above all, auxiliary devices in the shaping of an ideological, political and pedagogical line proper to the military catholic nationalism.

  2. 蟾蜍壶菌病病原遗传分化研究%Genetic Differentiation of the Pathogen of Batrachochytrium dendrobatidis in Toads

    Institute of Scientific and Technical Information of China (English)

    曾朝辉; 白世卓; 朱蕴绮; 王晓龙

    2011-01-01

    壶菌病为近年发现的两栖类动物重要传染病,对野生和养殖种群危害极大,为确定药用经济动物蟾蜍历史上壶菌病感染情况,提高养殖蟾蜍疾病防治水平,选取某博物馆馆藏采集于四川的蟾蜍标本32只,利用Taqman—MGB荧光探针定量PCR技术进行壶菌检测,并对定量PCR产物克隆、测序,通过序列比对和系统发育分析判定其来源。最终得到定量PCR标准曲线:Y=-3.0X+32.39;相关系数R0=0.9996;检测结果为阳性样本12只,检出率37.5%。同时系统发育分析表明,我国的壶菌存在一定程度的分化,一类与北美洲、南美洲、欧洲菌株呈现高度的亲缘关系;另一类则表现出与世界其他地区分布的壶菌有明显的不同,显示其独特性。这提示我国蟾蜍壶菌病的防制应更具针对性,不可盲目照搬国外经验。%The chytridiomycosis is a significant emerging disease of amphibians in recent years which seriuosly does harm to the wild and breeding population. To ascertain the condition of the Batrachochytrium dendrobatidis infection history in the population of toad, the medicinal economic animal, and enhance the prevention for this disease, 32 toad specimen collected from Sichwan keeping in a museum were assayed by Taqman-MGB fluorescence probe quantitative polymerase chain reaction to detect Batrachochytrium dendrobatidis. Besides, the products of QPCR were cloned and sequenced to identify the origin of the pathogen by sequence alignment and phylogenetie analysis. Finally we got the standard curve: Y = - 3.0X + 32.39 and the related coefficient: R2 = 0.999 6. Total 12 positive samples reported the detec- tion rate as 37.5 %. Meanwhile the phylogenetic analysis indicated that a certain extent differentiation of the chytrid fungi in our country exists. One kind of the tested strain showed highly genetic relationship with the strains from the North America, South America

  3. Hybridization and massive mtDNA unidirectional introgression between the closely related Neotropical toads Rhinella marina and R. schneideri inferred from mtDNA and nuclear markers

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    Schneider Horacio

    2011-09-01

    Full Text Available Abstract Background The classical perspective that interspecific hybridization in animals is rare has been changing due to a growing list of empirical examples showing the occurrence of gene flow between closely related species. Using sequence data from cyt b mitochondrial gene and three intron nuclear genes (RPL9, c-myc, and RPL3 we investigated patterns of nucleotide polymorphism and divergence between two closely related toad species R. marina and R. schneideri. By comparing levels of differentiation at nuclear and mtDNA levels we were able to describe patterns of introgression and infer the history of hybridization between these species. Results All nuclear loci are essentially concordant in revealing two well differentiated groups of haplotypes, corresponding to the morphologically-defined species R. marina and R. schneideri. Mitochondrial DNA analysis also revealed two well-differentiated groups of haplotypes but, in stark contrast with the nuclear genealogies, all R. schneideri sequences are clustered with sequences of R. marina from the right Amazon bank (RAB, while R. marina sequences from the left Amazon bank (LAB are monophyletic. An Isolation-with-Migration (IM analysis using nuclear data showed that R. marina and R. schneideri diverged at ≈ 1.69 Myr (early Pleistocene, while R. marina populations from LAB and RAB diverged at ≈ 0.33 Myr (middle Pleistocene. This time of divergence is not consistent with the split between LAB and RAB populations obtained with mtDNA data (≈ 1.59 Myr, which is notably similar to the estimate obtained with nuclear genes between R. marina and R. schneideri. Coalescent simulations of mtDNA phylogeny under the speciation history inferred from nuclear genes rejected the hypothesis of incomplete lineage sorting to explain the conflicting signal between mtDNA and nuclear-based phylogenies. Conclusions The cytonuclear discordance seems to reflect the occurrence of interspecific hybridization between these

  4. Influence of geology and human activity on the genetic structure and demography of the Oriental fire-bellied toad (Bombina orientalis).

    Science.gov (United States)

    Fong, Jonathan J; Li, Pi-Peng; Yang, Bao-Tian; Zhou, Zheng-Yan; Leaché, Adam D; Min, Mi-Sook; Waldman, Bruce

    2016-04-01

    The Oriental fire-bellied toad (Bombina orientalis) is a commonly used study organism, but knowledge of its evolutionary history is incomplete. We analyze sequence data from four genetic markers (mtDNA genes encoding cytochrome c oxidase subunit I, cytochrome b, and 12S-16S rRNA; nuDNA gene encoding recombination activating gene 2) from 188 individuals across its range in Northeast Asia to elucidate phylogeographic patterns and to identify the historic events that shaped its evolutionary history. Although morphologically similar across its range, B. orientalis exhibits phylogeographic structure, which we infer was shaped by geologic, climatic, and anthropogenic events. Phylogenetic and divergence-dating analyses recover four genetically distinct groups of B. orientalis: Lineage 1-Shandong Province and Beijing (China); Lineage 2-Bukhan Mountain (Korea); Lineage 3-Russia, Northeast China, and northern South Korea; and Lineage 4-South Korea. Lineage 2 was previously unknown. Additionally, we discover an area of secondary contact on the Korean Peninsula, and infer a single dispersal event as the origin of the insular Jeju population. Skyline plots estimate different population histories for the four lineages: Lineages 1 and 2 experienced population decreases, Lineage 3 remained stable, while Lineage 4 experienced a sharp increase during the Holocene. The timing of the population expansion of Lineage 4 coincides with the advent of rice cultivation, which may have facilitated the increase in population size by providing additional breeding habitat.

  5. Isolation and sequencing of doublesex/male abnormal 3 (DM related transcription factor (Dmrt genes from the Asian toad Bufo gargarizans (Cantor, 1842

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    Wen Chen

    2007-01-01

    Full Text Available The doublesex/male abnormal 3 (dsx/mab-3 or DM domain gene family involved in sexual development encodes putative transcription factors including a DNA-binding homology motif, the DM domain. We used highly degenerate primers to clone and sequence seven distinct DM related transcription factor (Dmrt genes from the Asian toad (Bufo gargarizans Cantor, 1842. A database search for the cloned sequences revealed the following percentage identity with the homologous Dmrt genes of the human: BgDmrt1 = 97%, BgDmrt2 = 97%, three isoforms of BgDmrt3 (BgDmrt3a = 93%, BgDmrt3b = 95%, BgDmrt3c = 100% and two isoforms of BgDmrt5 (BgDmrt5 = 97%, BgDmrt5 = 91%. Based on DM domain amino acid sequence similarities we constructed a phylogenetic tree which grouped vertebrate and invertebrate Dmrt genes into seven distinct subfamilies. The DM domains of both human and the newly-discovered Bufo gargarizans genes contained two conserved zinc-chelating sites (CCHC and HCCC, except BgDmrt3b, which contained the CCRC and HCCC sites.

  6. Drift rather than selection dominates MHC class II allelic diversity patterns at the biogeographical range scale in natterjack toads Bufo calamita.

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    Inga Zeisset

    Full Text Available Study of major histocompatibility complex (MHC loci has gained great popularity in recent years, partly due to their function in protecting vertebrates from infections. This is of particular interest in amphibians on account of major threats many species face from emergent diseases such as chytridiomycosis. In this study we compare levels of diversity in an expressed MHC class II locus with neutral genetic diversity at microsatellite loci in natterjack toad (Bufo (Epidalea calamita populations across the whole of the species' biogeographical range. Variation at both classes of loci was high in the glacial refugium areas (REF and much lower in postglacial expansion areas (PGE, especially in range edge populations. Although there was clear evidence that the MHC locus was influenced by positive selection in the past, congruence with the neutral markers suggested that historical demographic events were the main force shaping MHC variation in the PGE area. Both neutral and adaptive genetic variation declined with distance from glacial refugia. Nevertheless, there were also some indications from differential isolation by distance and allele abundance patterns that weak effects of selection have been superimposed on the main drift effect in the PGE zone.

  7. Chemical skin defence in the Eastern fire-bellied toad Bombina orientalis: an ultrastructural approach to the mechanism of poison gland rehabilitation after discharge

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    Sara Quagliata

    2008-12-01

    Full Text Available Type I serous glands in the skin of the Eastern yellow-bellied toad Bombina orientalis released their product massively after 10-3 M nor-adrenalin (NA stimulation, mimicking orthosympathetic control on poison emission in chemical skin defence. Features of cutaneous glands involved in this bulk discharge were observed under light and electron microscopes. Furthermore, restoration of depleted glands was followed after 1, 2 and 3 weeks, and compared with serous biosynthesis during larval gland development. Bulk discharge was caused by contraction of myoepithelial cells (mecs encircling the secretory units. Mec compression dramatically affected the secretory unit, but parts of this syncytial cytoplasm were saved from degeneration and cooperated in gland renewal with stem cells from the gland neck. These adenoblasts underwent proliferation and secretory cytodifferentiation, until merging with the syncytium. Cytoplasm that had resumed secretory activity showed the features typical of larval gland development: the endoplasmic reticulum (rer cisterns were aligned in close parallel arrangement and Golgi stacks released minute type I granules. Secretory rehabilitation led to increasing amounts of granule content. In the meantime, rough cisterns decreased in number and assumed the less ordered pattern described in control specimens. Data collected in the present study revealed that chemical skin defence in anurans is a multi-factorial mechanism involving specific activities: mechanical from mecs, biosynthetic from secretory syncytium and proliferative from intercalated stem cells.

  8. Structural and functional analogs of the novel mammalian neuropeptide, neuromedin S (NmS), in the dermal venoms of Eurasian bombinid toads.

    Science.gov (United States)

    Chen, Tianbao; Zhou, Mei; Walker, Brian; Harriot, Pat; Mori, Kenji; Miyazato, Mikiya; Kangawa, Kenji; Shaw, Chris

    2006-06-23

    We report the isolation and structural characterization of two neuromedin S (NmS) analogs, (NmS-17 and NmS-33), from the dermal venoms of Eurasian bombinid toads. NmS is a novel neuromedin U (NmU)-related peptide with potent anorexigenic and circadian rhythm-modulating properties recently discovered in mammals. Cloning of NmS precursor-encoding cDNAs from skin venom-derived libraries revealed the presence of a high degree of transcript splice variation comparable to that found previously for NmU in both amphibian skin and mammalian brain. Synthetic replicates of both amphibian NmS peptides evoked robust and dose-dependent transient increases in intracellular calcium ion concentrations in CHO cells that had been stably transfected with either FM-3/GPR66 or FM-4/TGR-1 human NmU receptors. The potency and efficacy of these amphibian skin peptides at such receptors were comparable to those observed with human NmS and rat NmS. These data show that NmS and NmU genes had already diverged at the level of the Amphibia and that differential splicing of their transcribed mRNAs has been highly conserved throughout tetrapod vertebrate evolution indicative of fundamental biological function. NmS is additionally a novel neuropeptide homolog that can be added to the biologically active peptide arsenal of amphibian venom/defensive skin secretions.

  9. Influence of geology and human activity on the genetic structure and demography of the Oriental fire-bellied toad (Bombina orientalis).

    Science.gov (United States)

    Fong, Jonathan J; Li, Pi-Peng; Yang, Bao-Tian; Zhou, Zheng-Yan; Leaché, Adam D; Min, Mi-Sook; Waldman, Bruce

    2016-04-01

    The Oriental fire-bellied toad (Bombina orientalis) is a commonly used study organism, but knowledge of its evolutionary history is incomplete. We analyze sequence data from four genetic markers (mtDNA genes encoding cytochrome c oxidase subunit I, cytochrome b, and 12S-16S rRNA; nuDNA gene encoding recombination activating gene 2) from 188 individuals across its range in Northeast Asia to elucidate phylogeographic patterns and to identify the historic events that shaped its evolutionary history. Although morphologically similar across its range, B. orientalis exhibits phylogeographic structure, which we infer was shaped by geologic, climatic, and anthropogenic events. Phylogenetic and divergence-dating analyses recover four genetically distinct groups of B. orientalis: Lineage 1-Shandong Province and Beijing (China); Lineage 2-Bukhan Mountain (Korea); Lineage 3-Russia, Northeast China, and northern South Korea; and Lineage 4-South Korea. Lineage 2 was previously unknown. Additionally, we discover an area of secondary contact on the Korean Peninsula, and infer a single dispersal event as the origin of the insular Jeju population. Skyline plots estimate different population histories for the four lineages: Lineages 1 and 2 experienced population decreases, Lineage 3 remained stable, while Lineage 4 experienced a sharp increase during the Holocene. The timing of the population expansion of Lineage 4 coincides with the advent of rice cultivation, which may have facilitated the increase in population size by providing additional breeding habitat. PMID:26748269

  10. Effects of temperature on embryonic and larval development and growth in the natterjack toad (Bufo calamita in a semi-arid zone

    Directory of Open Access Journals (Sweden)

    Sanuy, D.

    2008-06-01

    Full Text Available Temperature affects the duration of embryonic and larval periods in amphibians. Plasticity in time to metamorphosis is especially important in amphibian populations of Mediterranean semi-arid zones where temperatures are high and precipitation is low, increasing the rate of pond desiccation. In order to test the influence of water temperature on the larval development and growth of the natterjack toad (Bufo calamita, we collected two spawns in a semi¿arid zone at Balaguer (Lleida, NE Iberian peninsula. Approximately 50 (+/-10 eggs (stage 14-16 were raised in the lab at different temperature conditions: 10, 15, 20, 22.5 and 25ºC with 12:12 photoperiod. The results show a lengthening of development time with decreasing temperatures and a better survival performance of B. calamita to high temperatures. However, mean size at metamorphosis was not different across treatments, thus, suggesting that this population of B. calamita requires a minimum size to complete the metamorphosis. This study is the first approach to examine the effects that climatic factors have on the growth and development of B. calamita in semi-arid zones.

  11. Low temperature induces oocytes p34cdc2 synthesis and accumulation—the acquisition of competence to resume meiosis in toad oocytes

    Institute of Scientific and Technical Information of China (English)

    LUJINING; ZHENGGU; 等

    1996-01-01

    Full grown oocytes derived from Bufo Bufo gargarizans rearing at high temperature environment (24℃), never underwent GVBD after progesterone treatment.No p34cdc2 Hl kinase activity was detected in the oocytes after progesterone stimulation or OA microinjection;Western blotting analysis showed that the level of p34cdc2 and p33 in the oocytes are significantly lower than those in the oocytes derived from the hibernating toads (below 10℃).35S-Met incorporation analysis showed that when the oocytes were incubated at 6℃,synthesis of about thirty defferent polypeptides was promoted or induced,including p34cdc2 and some other p13suc1-binding proteins.All these results indicated that a low temperature environment is essential for the oocytes of Bufo Bufo gargarizans to express and stord some cell cycle drivers and its regulators,and to gain the maturation competence.These results will also provide a nwe clue for explaining the molecular mechanisms why gametogenesis of some organisms depends on a relative low temperature and how to maintain the geographical distribution of some animals.

  12. The Feeding Habits of Toad-headed Lizard (Phrynocephalus frontalis) in Autumn%草原沙蜥秋季食性分析

    Institute of Scientific and Technical Information of China (English)

    赵雪; 毕俊怀; 刘睿; 何志超; 陈绍勇

    2013-01-01

    We studied the food habits of Toad-headed Lizard (Phrynocephalus frontalis) collected in the Erdos region of Inner Mongolia using stomach dissection.The results show that Toad-headed Lizard prefers insects which account for 95.8% of all the food items in the period from August to September.No significant difference in food items was found between male and female although the index of food diversity (IFD) and the breadth of trophic niche (BTN) were greater in males than those in females.No any difference in food habits was found between adults and subadults or between subadults and juveniles,however,significant difference was detected between adults and juveniles.The percent similarity of food index was great between sexes and lower in different age group.The IFD and the BTN in different ages was the greatest in adults and the lowest in juveniles.The general beneficial coefficient,the beneficial coefficient in different gender and ages were VTotal =22.44%,VFemale =12.76%,VMale =9.83%.The P.frontalis is a species beneficial to the desert steppe.%利用剖胃法对采自内蒙古自治区鄂尔多斯库布齐沙漠的草原沙蜥(Phrynocephalus frontalis)进行食性分析研究.结果表明,该地区的草原沙蜥在8~9月间,以昆虫类动物为主要食物,占全部食物的95.8%.不同性别草原沙蜥取食的食物种类差异不显著,雌雄个体的食物百分率相似性指数及营养生态位重叠值均较大,雄性的食物多样性指数(IFD)及营养生态位宽度(BTN)均大于雌性.成体和亚成体之间以及亚成体和幼体之间食物种类存在差异但不显著,而成体和幼体间的食物种类差异极显著,不同年龄草原沙蜥的食物百分率相似性指数较小,IFD值与BTN值均是成体最大,幼体最小.总有益系数、不同性别的有益系数分别为V总=22.44%,V雌=12.76%,V雄=9.83%,草原沙蜥是对荒漠化草原有益的类群.

  13. Humoral immune alterations caused by lead: studies on an adult toad model Alteraciones inmunes humorales causadas por plomo: estudios en un modelo de sapo adulto

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    Carolina E. Rosenberg

    2007-07-01

    Full Text Available There is evidence that environmental metal levels affect the immune function. In the particular case of the impact of heavy metals, information available suggests that the immune system is a target for low-dose Pb exposure. Among vertebrates it was shown that amphibians are capable of forming antibodies against a variety of antigens, causing several responses such as anaphylactic response and rejecting grafts. In this study, the production of antibodies was assessed against sheep red blood cells (SRBC in the anuran Bufo arenarum after six weekly injections of sublethal doses of lead (50 mg.kg-1, as lead acetate. Natural antibodies (natural heteroagglutinins were also quantified against SRBC. Both assessments were carried out employing an ELISA method developed to this end, measuring absorbance (A. For natural anti-SRBC antibodies in both control (C and Pb treated (T toads, there was a non significant tendency to increase the initial absorbances (C initial: 0.69±0.39 A; T initial: 0.54±0.30 A, relative to those registered at the end of the experiments (C final: 0.89±0.49 A; T final: 0.76±0.31A; the T/C ratios also did not show changes. The only significant difference was found between initial and final samples from lead-treated toads (pExiste evidencia de que los niveles de metal ambientales afectan la función inmune. En el caso particular del impacto de metales pesados, la información disponible sugiere que el sistema inmune es un blanco para la exposición a bajas dosis de Pb. Entre los vertebrados, se ha mostrado que los anfibios son capaces de formar anticuerpos contra una variedad de antígenos, que causan diversas respuestas, tales como respuesta anafiláctica y rechazo de injertos. En este estudio, la producción de anticuerpos fue evaluada contra eritrocitos de oveja (EO en el anuro Bufo arenarum, luego de seis inyecciones semanales de dosis subletales de plomo (50 mg.kg-1, como acetato de Pb. Los anticuerpos naturales

  14. Synergy between glyphosate- and cypermethrin-based pesticides during acute exposures in tadpoles of the common South American toad Rhinella arenarum.

    Science.gov (United States)

    Brodeur, Julie Céline; Poliserpi, María Belén; D'Andrea, María Florencia; Sánchez, Marisol

    2014-10-01

    The herbicide glyphosate and the insecticide cypermethrin are key pesticides of modern management in soy and corn cultures. Although these pesticides are likely to co-occur in ephemeral ponds or aquatic systems supporting amphibian wildlife, the toxicological interactions prevailing in mixtures of these two pesticides have been little studied. The current study evaluated the toxicity of equitoxic and non-equitoxic binary mixtures of glyphosate- and cypermethrin-based pesticides to tadpoles of the common South American toad, Rhinella arenarum. Two different combinations of commercial products were tested: glyphosate Glifosato Atanor®+cypermethrin Xiper® and glyphosate Glifoglex®+cypermethrin Glextrin®. When tested individually, the formulations presented the following 96 h-LC50s: Glifosato Atanor® 19.4 mg ae L(-1) and Glifoglex 72.8 mg ae L(-1), Xiper® 6.8 mg L(-1) and Glextrin® 30.2 mg L(-1). Equitoxic and non-equitoxic mixtures were significantly synergic in both combinations of commercial products tested. The magnitude of the synergy (factor by which toxicity differed from concentration addition) was constant at around twofold for all tested proportions of the glyphosate Glifoglex®+cypermethrin Glextrin® mixture; whereas the magnitude of the synergy varied between 4 and 9 times in the glyphosate Glifosato Atanor®+cypermethrin Xiper® mixture. These results call for more research to be promptly undertaken in order to understand the mechanisms behind the synergy observed and to identify and quantify the extent of its environmental impacts. PMID:25048890

  15. Strong reproductive barriers in a narrow hybrid zone of West-Mediterranean green toads (Bufo viridis subgroup with Plio-Pleistocene divergence

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    Perrin Nicolas

    2010-07-01

    Full Text Available Abstract Background One key question in evolutionary biology deals with the mode and rate at which reproductive isolation accumulates during allopatric speciation. Little is known about secondary contacts of recently diverged anuran species. Here we conduct a multi-locus field study to investigate a contact zone between two lineages of green toads with an estimated divergence time of 2.7 My, and report results from preliminary experimental crosses. Results The Sicilian endemic Bufo siculus and the Italian mainland-origin B. balearicus form a narrow hybrid zone east of Mt. Etna. Despite bidirectional mtDNA introgression over a ca. 40 km North-South cline, no F1 hybrids could be found, and nuclear genomes display almost no admixture. Populations from each side of the contact zone showed depressed genetic diversity and very strong differentiation (FST = 0.52. Preliminary experimental crosses point to a slightly reduced fitness in F1 hybrids, a strong hybrid breakdown in backcrossed offspring (F1 x parental, with very few reaching metamorphosis and a complete and early mortality in F2 (F1 x F1. Conclusion Genetic patterns at the contact zone are molded by drift and selection. Local effective sizes are reduced by the geography and history of the contact zone, B. balearicus populations being at the front wave of a recent expansion (late Pleistocene. Selection against hybrids likely results from intrinsic genomic causes (disruption of coadapted sets of genes in backcrosses and F2-hybrids, possibly reinforced by local adaptation (the ranges of the two taxa roughly coincide with the borders of semiarid and arid climates. The absence of F1 in the field might be due to premating isolation mechanisms. Our results, show that these lineages have evolved almost complete reproductive isolation after some 2.7 My of divergence, contrasting sharply with evidence from laboratory experiments that some anuran species may still produce viable F1 offspring after > 20

  16. Binding of adrenergic ligands to liver plasma membrane preparations from the axolotl, Ambystoma mexicanum; the toad, Xenopus laevis; and the Australian lungfish, Neoceratodus forsteri.

    Science.gov (United States)

    Janssens, P A; Grigg, J A

    1988-09-01

    The beta-adrenergic ligand iodocyanopindolol (ICP) bound specifically to hepatic plasma membrane preparations from the axolotl, Ambystoma mexicanum (Bmax, 40 fmol/mg protein (P) at free concentration above 140 pM; KD, 42 pM); the toad, Xenopus laevis (Bmax, 200 fmol/mg P at 1 nM; KD, 300 pM); and the Australian lungfish, Neoceratodus forsteri (Bmax, 100 fmol/mg P at 5 nM). For the lungfish, the Scatchard plot was curved showing two classes of binding site with KD's of 20 and 500 pM. Neither the alpha 1-adrenergic ligand prazosin nor the alpha 2-adrenergic ligand yohimbine bound specifically to hepatic membrane preparations from any of the three species. Several adrenergic ligands displaced ICP from hepatic membrane preparations of all three species with KD's of Axolotl--propranolol, 50 nM; isoprenaline, 600 nM; adrenaline, 10 microM; phenylephrine, 20 microM; noradrenaline, 40 microM; and phentolamine, greater than 100 microM; X. laevis--propranolol, 30 nM; isoprenaline, 100 microM; adrenaline, 200 microM; noradrenaline, 300 microM; phenylephrine, 1 mM; and phentolamine, greater than 1 mM; N. forsteri,--propranolol, 25 nM; isoprenaline, 1 microM; adrenaline, 20 microM; phenylephrine, 35 microM; noradrenaline, 600 microM; and phentolamine, 400 microM. These findings suggest that alpha-adrenergic receptors are not present in hepatic plasma membrane preparations from these three species and that the hepatic actions of catecholamines are mediated via beta-adrenergic receptors. The order of binding of the beta-adrenergic ligands suggests that the receptors are of the beta 2 type.

  17. Effects of landscape composition and wetland fragmentation on frog and toad abundance and species richness in Iowa and Wisconsin, U.S.A

    Science.gov (United States)

    Knutson, Melinda G.; Sauer, John R.; Olsen, Douglas A.; Mossman, Michael J.; Hemesath, Lisa M.; Lannoo, Michael J.

    1999-01-01

    Management of amphibian populations to reverse recent declines will require defining high-quality habitat for individual species or groups of species, followed by efforts to retain or restore these habitats on the landscape. We examined landscape-level habitat relationships for frogs and toads by measuring associations between relative abundance and species richness based on survey data derived from anuran calls and features of land-cover maps for Iowa and Wisconsin. The most consistent result across all anuran guilds was a negative association with the presence of urban land. Upland and wetland forests and emergent wetlands tended to be positively associated with anurans. Landscape metrics that represent edges and patch diversity also had generally positive associations, indicating that anurans benefit from a complex of habitats that include wetlands. In Iowa the most significant associations with relative abundance were the length of the edge between wetland and forest ( positive) and the presence of urban land (negative). In Wisconsin the two most significant associations with relative abundance were forest area and agricultural area ( both positive). Anurans had positive associations with agriculture in Wisconsin but not in Iowa. Remnant forest patches in agricultural landscapes may be providing refuges for some anuran species. Differences in anuran associations with deep water and permanent wetlands between the two states suggest opportunities for management action. Large-scale maps can contribute to predictive models of amphibian habitat use, but water quality and vegetation information collected from individual wetlands will likely be needed to strengthen those predictions. Landscape habitat analyses provide a framework for future experimental and intensive research on specific factors affecting the health of anurans.

  18. Blood lead levels, δ-ALAD inhibition, and hemoglobin content in blood of giant toad (Rhinella marina) to assess lead exposure in three areas surrounding an industrial complex in Coatzacoalcos, Veracruz, Mexico.

    Science.gov (United States)

    Ilizaliturri-Hernández, César Arturo; González-Mille, Donaji Josefina; Mejía-Saavedra, Jesús; Espinosa-Reyes, Guillermo; Torres-Dosal, Arturo; Pérez-Maldonado, Iván

    2013-02-01

    The Coatzacoalcos Region in Veracruz, Mexico houses one of the most important industrial complexes in Mexico and Latin America. Lead is an ubiquitous environmental pollutant which represents a great risk to human health and ecosystems. Amphibian populations have been recognized as biomonitors of changes in environmental conditions. The purpose of this research is to measure exposure to lead and evaluate hematological and biochemical effects in specimens of giant toads (Rhinella marina) taken from three areas surrounding an industrial complex in the Coatzacoalcos River downstream. Lead levels in toads' blood are between 10.8 and 70.6 μg/dL and are significantly higher in industrial sites. We have found a significant decrease in the delta-aminolevulinic acid dehydratase (δ-ALAD) activity in blood from 35.3 to 78 % for the urban-industrial and industrial sites, respectively. In addition, we have identified a strong inverse relationship between the δ-ALAD activity and the blood lead levels (r = -0.84, p marina can be considered a good biomonitor of the δ-ALAD activity inhibition and hematological alterations at low lead concentrations. PMID:22580791

  19. A new species of the Rhinella margaritifera species group (Anura, Bufonidae) from the montane forest of the Selva Central, Peru

    OpenAIRE

    Jiri Moravec; Edgar Lehr; Juan Carlos Cusi; Jesus Cordova; Vaclav Gvozdik

    2014-01-01

    We describe a new species of the bufonid toad genus Rhinella from transition montane forest of the buffer zones of the Yanachaga-Chemillén National Park and the Pui Pui Protected Forest (eastern slopes of Andes, Selva Central, Peru). The new species belongs to the Rhinella margaritifera species group (confirmed by mtDNA data) and differs from all its members by the absence of tympanic membrane and tympanic annulus. It is characterized by medium size (SVL 57.5–65.5 mm, n = 5), mod...

  20. LA DIMENSIÓN ARGUMENTATIVA DE LAS MEMORIAS DISCURSIVAS: EL CASO DE LOS DISCURSOS GOLPISTAS DE LA PRENSA ESCRITA ARGENTINA (1930-1976 THE ARGUMENTATIVE DIMENSION IN DISCURSIVE MEMOIRS: THE CASE OF THE COUP D’ETAT DISCOURSES IN THE ARGENTINIAN PRESS (1930-1976

    Directory of Open Access Journals (Sweden)

    María Alejandra Vitale

    2009-06-01

    Full Text Available El propósito de este artículo es caracterizar la dimensión argumentativa de las memorias discursivas, específicamente en el caso de los editoriales y comentarios emitidos por la prensa escrita argentina para apoyar los sucesivos golpes de Estado durante el periodo 1930-1976. Para estudiar esta dimensión argumentativa en el caso aquí analizado, se denomina memoria retórico-argumental al retorno (transformación u olvido, en una serie discursiva de estrategias persuasivas que tienen la función de generar la adhesión a dichos golpes militares. Se siguieron dos vías para tal fin, en el marco de la tendencia francesa de Análisis del Discurso y desde una perspectiva retórica de estudio de la argumentación: el análisis de los tópicos y de las técnicas argumentativas.This article seeks to characterize the argumentative dimension of the discursivememory (Courtine, 1981, 1994, specifically in the case of the editorials and comments issued by the Argentinian written press in order to support the successive Coups d´Etat, during the period of 1930-1976. To analize this argumentative dimension, we called argumentative-rhetoric memory the return (the transformation or oblivion in the discursive series of persuasive strategies which, in the case here analyzed, have the function of creating the political adhesion to such Coups d´Etat. Two ways were followed within the French tendency of discourse analysis (Charaudeau & Maingueneau, 2005; Maingueneau, 1996 and from the rhetoric perspective of study of argumentation (Perelman y Olbrechts-Tyteca, 1989; Amossy, 2000: the analysis of the topics and the argumentative techniques.

  1. 花背蟾蜍皮肤结构及其抗氧化和免疫功能的研究%Microstructure of toad (Bufo raddei) andits antioxidant and immune function

    Institute of Scientific and Technical Information of China (English)

    高凤娟; 李丕鹏; 陆宇燕

    2015-01-01

    In order to understand the skin structure and function of the toad (Bufo raddei),the conventional paraffin section technique and ELISA were adopted to observe the microstructural characteristics of its dorsal skin,ventral skin and skin glands;and determine the contents of SOD,CAT,MDA,TLR4 andβD-1 of the dorsal skin and ventral skin, respectively.The results show that the toad skin structures are similar to other amphibians.That is the ventral cuticle thicker than the dorsal,the dorsal epidermis and dermis thicker than the ventral,granular glands mainly in the dorsal skin,and mucous glands in the ventral skin.SOD and TLR4 examined in the ventral skin are higher than in the dorsal skin,CAT containing in the dorsal skin is higher than in the ventral skin,but MDA andβD-1 are similar in these two areas.In conclusion,the structures and related protein levels of the toad skin closely adapt to the living environment,and have the antioxidant capacities and natural immune functions.%为了深入了解花背蟾蜍(Bufo raddei Strauch)皮肤显微结构及其相关功能,利用石蜡切片及酶联免疫吸附反应技术,观察了花背蟾蜍背腹侧皮肤及其皮肤腺的显微结构特点,分别测定了背、腹侧皮肤中 SOD、CAT、MDA、TLR4和βD-1含量。结果:花背蟾蜍皮肤结构与其他两栖类皮肤结构基本相同,其角质层腹侧较背侧厚,表皮和真皮背侧较腹侧厚;颗粒腺主要存在于背侧,而黏液腺主要存在于腹侧。SOD和TLR4含量腹侧皮肤高于背侧皮肤;CAT含量背侧皮肤较腹侧高;MDA和βD-1含量在背腹皮肤中相近。结论:花背蟾蜍皮肤结构和相关蛋白水平能够较好的适应其生境,并具有一定的抗氧化能力和天然免疫功能。

  2. Microstructure of toad (Bufo raddei) andits antioxidant and immune function%花背蟾蜍皮肤结构及其抗氧化和免疫功能的研究

    Institute of Scientific and Technical Information of China (English)

    高凤娟; 李丕鹏; 陆宇燕

    2015-01-01

    In order to understand the skin structure and function of the toad (Bufo raddei),the conventional paraffin section technique and ELISA were adopted to observe the microstructural characteristics of its dorsal skin,ventral skin and skin glands;and determine the contents of SOD,CAT,MDA,TLR4 andβD-1 of the dorsal skin and ventral skin, respectively.The results show that the toad skin structures are similar to other amphibians.That is the ventral cuticle thicker than the dorsal,the dorsal epidermis and dermis thicker than the ventral,granular glands mainly in the dorsal skin,and mucous glands in the ventral skin.SOD and TLR4 examined in the ventral skin are higher than in the dorsal skin,CAT containing in the dorsal skin is higher than in the ventral skin,but MDA andβD-1 are similar in these two areas.In conclusion,the structures and related protein levels of the toad skin closely adapt to the living environment,and have the antioxidant capacities and natural immune functions.%为了深入了解花背蟾蜍(Bufo raddei Strauch)皮肤显微结构及其相关功能,利用石蜡切片及酶联免疫吸附反应技术,观察了花背蟾蜍背腹侧皮肤及其皮肤腺的显微结构特点,分别测定了背、腹侧皮肤中 SOD、CAT、MDA、TLR4和βD-1含量。结果:花背蟾蜍皮肤结构与其他两栖类皮肤结构基本相同,其角质层腹侧较背侧厚,表皮和真皮背侧较腹侧厚;颗粒腺主要存在于背侧,而黏液腺主要存在于腹侧。SOD和TLR4含量腹侧皮肤高于背侧皮肤;CAT含量背侧皮肤较腹侧高;MDA和βD-1含量在背腹皮肤中相近。结论:花背蟾蜍皮肤结构和相关蛋白水平能够较好的适应其生境,并具有一定的抗氧化能力和天然免疫功能。

  3. Chloride channels in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Rasmussen, B E

    1982-01-01

    - ions through this pathway. Experimental analysis of the gating kinetics is rendered difficult owing to a contamination of the gated currents by cellular ion redistribution currents. To obtain insight into the effects of accumulation-depletion currents on voltage clamp currents of epithelial membranes......, a mathematical model of the epithelium has been developed for computer analysis. By assuming that the apical membrane Cl- permeability is governed by a single gating variable (Hodgkin-Huxley kinetics), the model predicts fairly well steady-state current-voltage curves, the time course of current activations from...... a closed state, and the dependence of unidirectional fluxes on potential. Other predictions of the model do not agree with experimental findings, and it is suggested that the gating kinetics are governed by rate coefficients that also depend on the holding potential. Evidence is presented that Cl...

  4. 催产素对蟾蜍离体坐骨神经-腓肠肌收缩的影响%Effect of Oxytocin on the Isolated Toad Sciatic Nerve Gastrocnemius Contraction

    Institute of Scientific and Technical Information of China (English)

    刘晓霞; 付立波

    2015-01-01

    采用常规方法剥离制备神经-腓肠肌标本,分别用浸有0.5%、1%和1.5%催产素的纱布浸润标本,浸润5min后,测量蟾蜍坐骨神经-腓肠肌的阈强度(mv)、收缩幅度(g)以及收缩潜伏期(ms),与放入正常任氏液作比较。经0.5%的催产素浸润后,腓肠肌的阈强度无明显变化,收缩幅度增大,且潜伏期时间缩短;经1%的催产素浸润后,腓肠肌的阈强度减小,收缩幅度增大,潜伏期时间相应缩短;而经1.5%浓度的催产素浸润后,腓肠肌的阈强度、收缩幅度以及潜伏期均无明显变化。较低浓度催产素可以提高骨骼肌收缩的兴奋性,但受药物剂量的限制。超过一定范围,骨骼肌收缩不随催产素浓度变化或随浓度增加骨骼肌的收缩能力相应减弱。%Objective:To investigate the effect of oxytocin effect on isolated toad sciatic nerve gastrocnemius on -their contractile activi-ty.Methods:Method for preparing specimen gastrocnemius nerve -using conventional stripping process for the preparation of specimens, the gastrocnemius muscle of toad sciatic nerve -, respectively 0.5%, 1%and 1.5%leaching oxytocin gauze infiltration specimens, af-ter infiltration 5 minutes, measure the toad sciatic nerve of gastrocnemius threshold intensity ( mv) , contraction amplitude ( g) , and con-traction latency (MS).Results:After 0.5%of oxytocin after the invasion (P>0.05), the threshold intensity of gastrocnemius muscle had no obvious change, contraction amplitude increases, and shorten the latency time.After 1%of oxytocin after infiltration, reduce the threshold intensity of gastrocnemius muscle contraction amplitude increases, the contraction latencythe time gets shorter.The 1.5%con-centrations of oxytocin after the invasion (P>0.05), gastrocnemius muscle contraction amplitude and latency, threshold intensity had no obvious change.Conclusion:Contraction of the skeletal muscle affected by oxytocin

  5. USO PREHISPÁNICO DE LAS PALMERAS SYAGRUS ROMANZOFFIANA Y BUTIA YATAY EN EL NORDESTE ARGENTINO: APORTES DESDE LA ETNOGRAFÍA Y LA BIOMETRÍA / Prehispanic use of Syagrus romanzoffiana and Butia yatay palms in the Argentinian Northeast: contributions from eth

    Directory of Open Access Journals (Sweden)

    Mariano Bonomo

    2014-12-01

    Full Text Available La distribución meridional de las palmeras de la familia Arecaceae (=Palmae en Sudamérica alcanza el sur de la cuenca del Plata. Este artículo se centra en dos especies de esta familia, Syagrus romanzoffiana y Butia yatay, cuyos micro y macrorrestos se han preservado en los sitios arqueológicos del Holoceno tardío en el Nordeste argentino. El registro arqueológico indica que fueron importantes para la alimentación y, seguramente, en la tecnología. Además, grupos etnográficos pertenecientes a distintos troncos lingüísticos (tupí, macro-jê, guaycurú muestran que estos vegetales tuvieron un rol central en el Plata. A pesar de ello, hasta el presente estudio no se había efectuado en el Nordeste un análisis sistemático y desde distintas líneas de trabajo que permitan incrementar la información taxonómica y económica que se puede obtener de los restos de ambas palmeras. A partir de la revisión de la literatura etnográfica, la determinación de la utilidad neta de los frutos y el estudio de los atributos cuali-cuantitativos de los endocarpos, se establecen los usos potenciales de este recurso y la productividad de sus frutos y se brindan herramientas para la identificación taxonómica. Todo ello permite profundizar los conocimientos sobre la utilización prehispánicas de las palmeras en la región. Palabras clave: cuenca del Plata; Arecaceae; productividad de los frutos; identificación taxonómica. Prehispanic use of Syagrus romanzoffiana and Butia yatay palms in the Argentinian Northeast: contributions from ethnography and biometrics Abstract The southern distribution of the Arecaceae palm family (=Palmae in southern South America reached the La Plata Basin. This paper focuses on two species of this family, Syagrus romanzoffiana and Butia yatay which micro and macro-remains have been preserved in Late Holocene archaeological sites in the Argentinean Northeast. The archaeological record indicates that they were important in

  6. New Karyological and Morphometric Data on Poorly Known Bufo surdus and Bufo luristanicus in Comparison with Data of Diploid Green Toads of the Bufo viridis Complex from South of Iran

    Institute of Scientific and Technical Information of China (English)

    Fatemeh FAKHARZAEH; Jamshid DARVISH; Haji Gholi KAMI; Fereshteh GHASEMZADEH; Eskandar RASTEGAR-POUYANI

    2014-01-01

    Previous studies on the Bufo viridis complex, which is distributed broadly across Iran, are incomplete and restricted to a few regions or a few samples. In this paper a new detailed study on the B. viridis complex in southern of Iran (from West to East) is presented. The analysis of 18 morphometric characters with univariate and multivariate methods reveals significant differences between three members of the B. viridis complex namely B. variabilis, B. luristanicus, and B. surdus distributed in southern part of Iran. Our result help to resolve an old taxonomic problem about B. surdus subgroup (taxa closely related to B. surdus) conifrming that B. luristanicus and B. surdus are distinct species. Moreover, for the ifrst time we report and describe karyotype details of B. luristanicus and B. surdus which conifrmed that they are diploid. Karyological studies demonstrate that all toads from three mentioned species have 2n=22 chromosomes. These chromosomes are arranged into two groups. First group has six large chromosomes and the second group is composed of five small chromosomes. These chromosomes are metacentric or submetacentric. The number of submetacentric chromosomes is different in three mentioned species of B. viridis complex. Neither sexual heteromorphism, nor secondary constriction was observed in any pairs of chromosomes.

  7. 黄山地区人工养殖蟾蜍主要疾害及防治%Investigation and Prevention of Main Diseases of Artificial Breeding Toads in Huangshan Region

    Institute of Scientific and Technical Information of China (English)

    王德青; 唐鑫生

    2012-01-01

    2007年3月-2011年9月,对黄山地区人工养殖蟾蜍发生的主要疾害进行了调查,发现主要有腐皮病、红腿病、烂鳃病、胃肠炎、白内障、水霉病、气泡病等病害,车轮虫、舌杯虫和水蛭寄生虫害以及蛇、水虿、鸟等敌害。初步掌握了这些疾病的临床症状、病理变化、流行特点以及敌害种类,并对以上疾害提出了相应的防治措施。%The main diseases of artificial breeding toads in Huangshan region were investigated from March 2007 to September 2011. The investigation result shows there are decayed-skin, red-leg frog disease, decayed-cheek disease, enteritis, cataract, saprolegniasis, and bubble disease; three kinds of parasites (trichodinids, apisoma and sanguisuga) and some natural enemies (snake, dobson and bird). Further studies were made of the clinical symptoms, pathological changes, popular features, and predators of these diseases, and appropriate measures were put forward to prevent and treat them..

  8. Radioinhibition process in Argentinian garlic and onion bulbs

    Science.gov (United States)

    Curzio, O. A.; Croci, C. A.

    Technological aspects of garlic and onion bulbs subjected to the radioinhibition process and extended storage under warehouse conditions were studied. Garlic and onion of the "Colorado" and "Valenciana sintética 14" varieties respectively, were irradiated in dormancy period with an average dose of 50.0 Gy of 60Co gamma rays and kept in storage up to ten months post-harvest. Throughout the control period (180-300 days post-harvest) obvious benefits were attained as to reducing the weight loss and increasing the percentage of marketable bulbs. In general, the irradiated bulbs were superior to the non-irradiated ones with regard to the external aspect, firmness and internal aspect, while the odor of the bulbs was not affected by the process. The radioinhibition process does not seem to affect adversely the levels of dry matter, carbohydrates and ascorbic acid as well as the acidity in onion bulbs. In two marketing trials a very favourable reception was perceived in the consumer public regarding the quality of the products. These studies have promoted the construction of a multipurpose irradiation facility in the Universidad Nacional del Sur for the development of the radiation processing technology.

  9. [Physical activity and health habits in Argentinian undergraduates].

    Science.gov (United States)

    Pérez Ugidos, Guillermo; Laíño, Fernando A; Zelarayán, Julio; Márquez, Sara

    2014-10-01

    Objetivo: El deterioro de los hábitos saludables en los jóvenes, particularmente universitarios, justifica su investigación en dichas poblaciones. El objetivo del presente estudio es analizar los niveles de actividad física en estudiantes de la Universidad Nacional de La Matanza (Argentina), intentando describir grupos homogéneos según características demográficas, de hábitos de salud y de percepción de bienestar, e identificando el nivel de actividad física que mejor describa a cada uno de los grupos. Metodología: Participaron 554 estudiantes (281 varones y 273 mujeres) de distintas carreras a los que se aplicó el Cuestionario Global de Actividad Física (GPAQ) y un instrumento sobre hábitos de salud, percepción de felicidad y diversas variables demográficas. Se calcularon medidas de tendencia central y variabilidad, así como los percentiles P25 y P75, para todas las variables. Se realizó una segmentación mediante análisis de clusters jerárquico, con un análisis de factores previo. Resultados: El 79,8% de los estudiantes, y el 97,2% de aquellos que cursaban Educación Física cumplían con las recomendaciones de realización de actividad física. Los alumnos que se identificaban con un nivel de actividad física alto eran los que cursaban en turno diurno, no consumían tabaco, alcohol ni drogas, no trabajaban, no tenían hijos ni pareja estable, y poseían un nivel socio- económico medio. Conclusiones: Se sugiere la necesidad de una sólida intervención educativa por parte de las universidades para fomentar hábitos saludables y la realización regular de actividad física, ya que tienen una responsabilidad social primaria respecto a estas problemáticas.

  10. [Bioethics in the new Argentinian Civil and Commercial Code].

    Science.gov (United States)

    Bergel, Salvador Darío

    2015-01-01

    Argentine has a new Civil and Commercial Code that will enter into force in August. This Code contains a series of rules relating to bioethics that have served to illustrate a brief comment on its contents. PMID:26665351

  11. In vitro antiplasmodial activity of extracts of Argentinian plants.

    Science.gov (United States)

    Debenedetti, S; Muschietti, L; van Baren, C; Clavin, M; Broussalis, A; Martino, V; Houghton, P J; Warhurst, D; Steele, J

    2002-05-01

    Fifteen extracts from nine selected Argentine medicinal plants were tested for their antiplasmodial activity in vitro by assessing their ability to inhibit the uptake of [3H]-hypoxanthine into the Plasmodium falciparum K1 pyrimethamine/chloroquine resistant strain. The methanol extract of Satureja parvifolia showed good antiplasmodial activity (IC(50) 3 microg/ml). Inhibition of the growth of P. falciparum was also observed with aqueous extracts of Buddleja globosa and S. parvifolia.

  12. RA-10: A New Argentinian Multipurpose Research Reactor

    International Nuclear Information System (INIS)

    A new multipurpose research reactor to replace RA-3 reactor has been decided to be built in Argentina to satisfy the increasing national and regional demands for radioisotopes. The project, supported by the National Administration, has started in 2010 and is planned to be operative in 2018. The expertise acquired in the country, in the design and licensing of nuclear reactors, encourage the National Atomic Energy Commission (CNEA) to face the challenge. INVAP S.E. is involved in the design and construction of the reactor facility and related installations, playing the role of main contractor. The RA-10 is a 30 MW thermal power reactor and is designed to achieve high performance neutrons production to fulfill the stakeholder's requirements in compliance with stringent safety regulations. The principal objectives of the facility are: to consolidate and increase the radioisotope production in order to cover future demands, to provide fuel and material testing irradiation facilities to support national technology development on this field, to offer new applications in the field of science and technology based on modern neutron techniques. The reactor is an open-pool facility with a compact core with MTR (Material Testing Reactor) low enriched uranium (LEU) fuel assemblies consisting of uranium silicide fuel plates, cladded in aluminum. Reactivity control is performed by hafnium plates. A heavy water reflector tank surrounds the core. It provides a high thermal neutron flux adequate to house irradiation facilities. A diverse and independent shutdown system is engineered through its drainage. The fundamental safety objective of the design is the radiological protection of the public, the personnel and the environment and consequently the design is based in three main principles: responsibility in safety management, defense-in-depth and safety features. Engineered Safety Features are provided which are capable of maintaining the reactor in a safe condition under all anticipated operational conditions and design basis event. (author)

  13. [Bioethics in the new Argentinian Civil and Commercial Code].

    Science.gov (United States)

    Bergel, Salvador Darío

    2015-01-01

    Argentine has a new Civil and Commercial Code that will enter into force in August. This Code contains a series of rules relating to bioethics that have served to illustrate a brief comment on its contents.

  14. FLORA ARGENTINA: NOVEDADES EN PRIMULACEAE Argentinian flora: novelties in Primulaceae

    Directory of Open Access Journals (Sweden)

    Sara G. Tressens

    2010-08-01

    Full Text Available

    Anagallis filiformis Cham. & Schltdl., especie no mencionada previamente para la Argentina,
    es citada, descripta e ilustrada. Se señala por primera vez A. arvensis L., ampliamente
    extendida en la Argentina, para las provincias de Corrientes y Misiones. Se incluye una clave
    para la identificación de las cuatro especies de Anagallis presentes en el país
    Anagallis filiformis Cham. & Schltdl., species not previously mentioned for Argentina is
    recorded, described and illustrated. A. arvensis L., largely widespread in Argentina, is reported
    for the first time from Corrientes and Misiones provinces. A key for the identification of the four
    species of Anagallis present in the country is also included

  15. [Consensus for antimicrobial susceptibility testing for Enterobacteriaceae. Subcommittee on Antimicrobials, SADEBAC (Argentinian Society of Clinical Bacteriology), Argentinian Association of Microbiology].

    Science.gov (United States)

    Famiglietti, A; Quinteros, M; Vázquez, M; Marín, M; Nicola, F; Radice, M; Galas, M; Pasterán, F; Bantar, C; Casellas, J M; Kovensky Pupko, J; Couto, E; Goldberg, M; Lopardo, H; Gutkind, G; Soloaga, R

    2005-01-01

    Taking into account previous recommendations from the National Committee for Clinical Laboratory Standards (NCCLS), the Antimicrobial Committee, Sociedad Argentina de Bacteriología Clínica (SADEBAC), Asociación Argentina de Microbiología (AAM), and the experience from its members and some invited microbiologists, a consensus was obtained for antimicrobial susceptibility testing and interpretation in most frequent enterobacterial species isolated from clinical samples in our region. This document describes the natural antimicrobial resistance of some Enterobacteriaceae family members, including the resistance profiles due to their own chromosomal encoded beta-lactamases. A list of the antimicrobial agents that should be tested, their position on the agar plates, in order to detect the most frequent antimicrobial resistance mechanisms, and considerations on which antimicrobial agents should be reported regarding to the infection site and patient characteristics are included. Also, a description on appropriate phenotypic screening and confirmatory test for detection of prevalent extended spectrum beta-lactamases in our region are presented. Finally, a summary on frequent antimicrobial susceptibility profiles and their probably associated resistance mechanisms, and some infrequent antimicrobial resistance profiles that deserve confirmation are outlined.

  16. Toads Give You Warts--Not!

    Science.gov (United States)

    Tomasek, Terry; Matthews, Catherine E.

    2008-01-01

    The authors provide activities through which teachers can share experiences in the outdoors with young children and teach them about herpetology, the study of amphibians and reptiles. Outdoor activities include observation, classification, and mapping. The authors also include activities for the classroom, including connections between the science…

  17. Arroyo Toad Range - CWHR [ds612

    Data.gov (United States)

    California Department of Resources — Vector datasets of CWHR range maps are one component of California Wildlife Habitat Relationships (CWHR), a comprehensive information system and predictive model...

  18. 鲜蟾皮外敷促进糖尿病大鼠皮肤溃疡愈合的实验研究%An experimental study of the promotion of healing of skin ulcers in diabetic rats by external application of fresh toad skin

    Institute of Scientific and Technical Information of China (English)

    张晓义; 唐祝奇; 刘春; 朱晓晖; 印彤; 王粹芳; 崔世维

    2013-01-01

    Objective: To study the effect of the treatment of skin ulcers in diabetic rats by external application of fresh toad skin and its possible mechanism of action. Methods: 42 male SD rats were randomly divided into three groups:the normal control group (12 rats), the diabetic skin ulcers model group (15 rats), and the diabetic skin ulcers treatment group (15 rats). A model of skin ulcers in rats was created, then fresh toad skin was applied on these ulcer sites, and how the ulcers got healed was observed. Pathologically, the wounded tissue structures around the ulcers were observed at the 2nd and 3rd weekends, and immunohistochemically, the expression of the wounded tissue vascular endothelial growth factor (VEGF) was observed. Results: Ulcers began to shrink after 2 weeks and scab after 3 weeks in the diabetic model group. By contrast, in the diabetic treatment group, the expression of VEGF was increased (15.6±2.2 μg/g vs. 48.3±4.2 μg/g, P<0.05) at the end of 2 weeks and sustained to the end of 3 weeks (19.5±3.2μg/g vs. 10.9±2.7μg/g, P<0.05), and meanwhile the wound healing cycle was shortened. Conclusions:External application of fresh toad skin can increase the expression of the wounded tissues VEGF and promote the healing of skin ulcers in diabetic rats.%目的:研究鲜蟾皮外敷对糖尿病大鼠皮肤溃疡的治疗作用及作用机制。方法:清洁级雄性SD大鼠42只,分为3组:正常对照组(12只)、糖尿病皮肤溃疡模型组(15只)、糖尿病皮肤溃疡治疗组(15只)。建立缺损性皮肤溃疡大鼠模型,鲜蟾皮外敷溃疡部位,观察溃疡愈合情况;大体病理观察第2、3周末溃疡组织结构,免疫组化观察血管内皮生长因子(VEGF)的表达,酶联免疫反应技术测定组织中VEGF含量。结果:模型组2周溃疡开始缩小,3周结痂,与对照组相比VEGF表达降低(15.6±2.2μg/g vs.48.3±4.2μg/g, P<0.05);与模型组相比,治疗组2

  19. How Preussag Became TUI : Kissing Too Many Toads Can Make You a Toad

    NARCIS (Netherlands)

    I. Dittmann (Ingolf); E.G. Maug (Ernst); C. Schneider (Christoph)

    2006-01-01

    textabstractIn the period 1997-2004, Preussag, a diversified German conglomerate of old economy businesses, changed itself into TUI, a company focused almost entirely on tourism and logistics. This paper analyzes how this strategy was executed and how it contributed to Preussag's underperformance of

  20. Carotenoid composition and vitamin A value of an Argentinian squash (Cucurbita moschata).

    Science.gov (United States)

    González, E; Montenegro, M A; Nazareno, M A; López de Mishima, B A

    2001-12-01

    The carotenoid composition of butternut squash (Cucurbita moschata) cultivated in the province of Santiago del Estero, Argentina, was determined. The main carotenoids isolated were identified as beta-carotene (beta,beta-carotene), alpha-carotene (beta,epsilon-carotene), and lutein (beta,epsilon-carotene-3,3'-diol) and the minor carotenoids, as phytofluene (7,8,11,12,7',8'-hexahydro-psi,psi-carotene), zeta-carotene (7,8,7',8'-tetrahydro-psi,psi-carotene), neurosporene (7,8-dihydro-psi,psi-carotene), violaxanthin (5,6,5',6'- diepoxy-5,6,5',6'-tetrahydro-beta,beta-carotene-3,3'-diol) and neoxanthin (5,6-epoxy-6,7-didehydro-5,6,5',6'-tetrahydro-beta,beta- carotene-3,5,3'-triol). In some samples, 5,6,5',6'-beta-carotene diepoxide, (5,6,5',6'-diepoxy-5,6,5',6'-tetrahydro-beta,beta-carotene) and flavoxanthin (5,8-epoxy-5,8-dihydro-beta,epsilon-carotene-3,3'-diol) were detected. The presence of cis-isomers of beta,beta-carotene was also detected by HPLC. The vitamin A value obtained was 432 micrograms RE/100 g fresh sample, which indicates that this vegetable is an important source of provitamin A.

  1. Synopsis of the Argentinian scarab genus Pseudogeniates Ohaus (Coleoptera, Scarabaeidae, Rutelinae

    Directory of Open Access Journals (Sweden)

    Mary Jameson

    2012-11-01

    Full Text Available The scarab beetle genus Pseudogeniates Ohaus (Scarabaeidae: Rutelinae: Rutelini is endemic to Argentina. The genus includes three species: P. cordobaensis Soula, P. intermedius Ohaus, and P. richterianus Ohaus. We characterize the genus, provide a key to species, redescribe and diagnose each species, provide spatial and temporal distributions, and discuss distributions of the species in relation to eco-regions and areas of endemism in Argentina.

  2. Epidemiological survey of Giardia spp. and Blastocystis hominis in an Argentinian rural community.

    Science.gov (United States)

    Minvielle, Marta Cecilia; Pezzani, Betina Cecilia; Cordoba, María Alejandra; De Luca, María Marta; Apezteguia, María Carmen; Basualdo, Juan Angel

    2004-09-01

    The aim of this study was to relate personal data, socio-cultural and environmental characteristics, and the presence of symptoms/signs with the frequencies of Giardia spp. and Blastocystis hominis among a rural population in Buenos Aires Province, Argentina. Of the surveyed population (350), 3.7% were infected with only Giardia spp. or 22.9% with B. hominis, and 2.3% were infected with both protozoa. The frequency of infection according to sex; 6.1% of males were infected and 1.6% of females by Giardia spp., 26.7% and 19.5% by B. hominis, and 2.4% and 2.2% by both parasites, respectively. Giardia spp. was detected in only three adults (over 14 years), but B. hominis was more frequent in adults than in children. The prevalences of these protozoa in this community are lower than those reported by other Argentinean studies, which is probably associated with the low density of the studied population (5.95 inhab/km2). Statistical analysis revealed that a male sex, flooding of the home, the use of a latrine, and an abdominal pain were correlated with the presence of these parasites, which indicate the importance of these factors in rural communities. PMID:15381860

  3. Effects of urban green areas on air temperature in a medium-sized Argentinian city

    Directory of Open Access Journals (Sweden)

    Alejandra S. Coronel

    2015-07-01

    Full Text Available Urban climate is the result of both atmospheric and geographic factors affecting a region, as well as the morphology, structures and human activities in a city. Urban vegetation in particular affects this climate at a local scale and provides many other social, economic and ecological benefits. Thus, it is important to explore the effects of different green areas used for urban and periurban agriculture and forestry activities (UPAF on daily atmospheric temperature and the required degrees of cooling or refrigerating temperature. Comfort temperatures were defined using a range 18-24°C and analyzed using actual measured as well as forecasted temperatures using a future scenario. Actual temperatures were recorded from September 2013 to August 2014 using digital sensors across eight sites in Rosario, Argentina: three in the central core with no vegetation, one in the central core with street trees, one in an urban agriculture site, one in a public park and two in periurban agricultural areas. Results show that air temperature in the central core with no vegetation were higher than those in other sites with vegetation during day and night, with the exception of the temperatures measured at the central core site with street trees. Findings also show that temperature effects in urban agricultural gardens of approximately 0.2 ha were similar to those of gardens and public parks 2-3 ha in size. Three UPAF types were classified according to cooling degree days, which decreased in order from (1 central core with no trees; (2 central core with street trees and public parks; and (3 urban and periurban agriculture areas. Conversely, the opposite trends for heating degree days were found. Results from this study can be used for integrating UPAF measures into climate change mitigation and urban planning policies in medium-sized cities in the developing world.

  4. Initial English Language Teacher Education: Processes and Tensions towards a Unifying Curriculum in an Argentinian Province

    Science.gov (United States)

    Banegas, Dario Luis

    2014-01-01

    In this reflective piece I discuss the process of developing a new unifying initial English language teacher education curriculum in the province of Chubut (Argentina). Trainers and trainees from different institutions were called to work on it with the aim of democratising curriculum development and enhancing involvement among agents. In the…

  5. Evaluation of the psychometric properties of the Gambling Motives Questionnaire in Argentinian young people and adults.

    Science.gov (United States)

    Pilatti, Angelina; Tuzinkievich, Francisco Benjamín

    2015-01-01

    The purpose of the present study was to evaluate, in a sample of young people and adults from the general community, the psychometric properties of two models developed for assessing gambling motives (Gambling Motives Questionnaire and Gambling Motives Questionnaire-Financial; GMQ and GMQ-F). Specifically, a confirmatory factor analysis was carried out to assess the fit of the two models to the data. Internal consistency of the scales was then analyzed. A multiple regression analysis was conducted to analyze the utility of gambling motives for predicting levels of gambling problem severity. The final sample was made up of 341 young people and adults, aged 18 to 60, who reported any gambling activity during the last six months. The maximum likelihood (ML) method with robust Satorra-Bentler correction was used to evaluate the fit of the models to the data. The results indicated that both the GMQ and the GMQ-F models show a reasonable fit to the data. All scales have adequate internal consistency values. Enhancement, coping and financial gambling motives were associated with greater severity of gambling problems. Overall, the results indicate that both models have adequate psychometric properties, though the GMQ-F appears to provide a more comprehensive alternative for assessing gambling motives in the general community. PMID:25879474

  6. Enrique Pichon-Rivière: origins of Argentinian social psychology

    OpenAIRE

    Gastón Becerra

    2015-01-01

    Enrique Pichon-Rivière (1907-1977) was one of the founders of social psychology in Argentina. Here we review his biography and institutional paths along with his theoretical and epistemological contributions. We argue that Enrique Pichon-Rivière evinced a critical attitude towards the disciplinary divisions, and the distance between academic knowledge and social praxis. Here we prioritize those aspects of his work that we consider most relevant to the social sciences, including their notions ...

  7. Argentinians and Peruvians in Mexico City, 1970-2009. Setting of a Transnational Digital Citizenship?

    OpenAIRE

    Fernández Tapia, Joselito

    2014-01-01

    Objective: to systematize and explain the relationship between Information and Communication Technologies -ICT and citizenship, mainly from the Internet. Methodology: a qualitative method, based on in-depth interviews, participant observation and content analysis of websites is used. The study responds to a transnational and intercultural approach to integration and citizenship.Results: state transnationalism and growing transnational networks through ICT are evidenced. They connect direct ne...

  8. Natural Resources and Local Development: The Argentinian Oilseed Complex and Biofuel Production

    Directory of Open Access Journals (Sweden)

    Eliana Scialabba

    2014-01-01

    Full Text Available Argentina is very rich in natural resources, particularly those linked to the oilseed production. Global demand and improved means of production, have resulted in a mature and developed production infrastructure geared toward export. This generates not just revenue, but also has other positive effects, such as the creation of jobs and sustainable development. In this context, biofuel production adds multidimensional value to the vegetable oil industry and generations many spin-off industries.

  9. Characterization of cellulolytic activities of environmental bacterial consortia from an Argentinian native forest.

    Science.gov (United States)

    Romano, Nelson; Gioffré, Andrea; Sede, Silvana M; Campos, Eleonora; Cataldi, Angel; Talia, Paola

    2013-08-01

    Cellulolytic activities of three bacterial consortia derived from a forest soil sample from Chaco region, Argentina, were characterized. The phylogenetic analysis of consortia revealed two main highly supported groups including Achromobacter and Pseudomonas genera. All three consortia presented cellulolytic activity. The carboxymethylcellulase (CMCase) and total cellulase activities were studied both quantitatively and qualitatively and optimal enzymatic conditions were characterized and compared among the three consortia. Thermal and pH stability were analyzed. Based on its cellulolytic activity, one consortium was selected for further characterization by zymography. We detected a specific protein of 55 kDa with CMCase activity. In this study, we have shown that these consortia encode for cellulolytic enzymes. These enzymes could be useful for lignocellulosic biomass degradation into simple components and for different industrial applications. PMID:23471693

  10. Biodiversity of Aspergillus section Nigri populations in Argentinian vineyards and ochratoxin A contamination.

    Science.gov (United States)

    Chiotta, María L; Ponsone, María L; Sosa, Débora M; Combina, Mariana; Chulze, Sofía N

    2013-12-01

    Aspergillus section Nigri are described as the main source of ochratoxin A (OTA) contamination in grapes and wine worldwide. The knowledge of the factors affecting grape contamination by species included in this section and OTA production is essential to be able to reduce their presence, not only to improve wine quality, but also to maintain their safety. Therefore, the aims of this study were to determine the incidence of Aspergillus section Nigri species harvested in different grape-growing regions from Argentina, their ability to produce OTA, to correlate with meteorological conditions and geographical coordinates with their prevalence and to evaluate the OTA natural occurrence in grapes and wines. The morphological identification showed that Aspergillus niger aggregate species were the most prevalent ones, followed by Aspergillus carbonarius and Aspergillus uniseriate. These populations were confirmed through using AFLP markers and sequencing and, Aspergillus tubingensis was separated from A. niger aggregate. Climatic factors, altitude, longitude and latitude have influenced on the distribution of species included in the section. A. carbonarius and A. niger were OTA producers but differed in their OTA producing ability. Temperature was the factor which influenced the most over the highest incidence of A. carbonarius in La Rioja and San Juan regions. The trellis system in vineyards and drip irrigation also influenced the species isolation. The OTA levels detected in grapes and wines were low, but grape variety was more important in susceptibility to fungal infection and OTA levels.

  11. Comparison of allele frequencies of eight STR loci from Argentinian Amerindian and European populations.

    Science.gov (United States)

    Sala, A; Penacino, G; Corach, D

    1998-10-01

    Eight STR systems (THO1, FABP, VWA, FES/FPS, HPRTB, F13A1, CSF1PO, and D6S366) were investigated in different ethnic groups of Argentina. Allele and genotype frequencies, power of exclusion, and discriminative power were investigated. Hardy-Weinberg expectations were calculated from heterozygosity levels. FST and G tests demonstrated that significant differences exist among the investigated populations for some of the eight STRs markers. The Wichi Indians are clearly separated from the Mapuche and Tehuelche, who in turn are closer to the European population, suggesting non-Amerindian admixture.

  12. Social protest and its representations in the Argentinian press: 1996-2002

    Directory of Open Access Journals (Sweden)

    Matías Artese

    2011-07-01

    Full Text Available This article presents the main findings of a research on the relation between physical confrontations and its interpretations in six episodes of protest between 1996 and 2002 in Argentina. In this period a profound economic and employment crisis affected most of the country's population. Consequently, it was a period in which a general increase of the cycle of social protests took place.Employing tools provided by Critical Discourse Analysis, we analyze the properties attributed to each of the six protests and repressive reaction of the State, through statements published by the press.The main objective is to review the field of dispute over the meaning of the actions and characteristics of the interpretations published at the precise moments that the institutional violence was applied, as the beginning of an explanation to the criminalization of protest.

  13. ENCOMS: Argentinian survey in cost of illness and unmet needs in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Celica Ysrraelit

    2014-05-01

    Full Text Available The objective of the study was to assess the cost of multiple sclerosis (MS patients in Argentina categorized by disease severity using a societal perspective. Method: Cross-sectional study including MS patients from 21 MS centers in 12 cities of Argentina. Patients were stratified by disease severity using the expanded disability status scale (EDSS (group 1 with EDSS score between 0 and 3; group 2 with EDSS >3 and 3 and <7, and USD 50,712 (95%CI 47,825-62,104 for patients with EDSS ≥7. Conclusions: This is the first Argentine study evaluating the costs of MS considering disease severity.

  14. Trade Liberalization, Exports, and Technology Upgrading: Evidence on the Impact of MERCOSUR on Argentinian Firms

    OpenAIRE

    Bustos, Paula

    2011-01-01

    This paper studies the impact of a regional free trade agreement, MERCOSUR, on technology upgrading by Argentinean firms. To guide empirical work, I introduce technology choice in Melitz?s (2003) model of trade with heterogeneous firms. The joint treatment of the technology adoption and exporting choices shows that the increase in revenues produced by trade integration can induce exporters to upgrade technology. An empirical test of the model reveals that firms in industries fa...

  15. Argentinian multi-wavelength scanning Raman lidar to observe night sky atmospheric transmission

    CERN Document Server

    Pallotta, Juan; Otero, Lidia; Chouza, Fernando; Raul, Delia; Gonzalez, Francisco; Etchegoyen, Alberto; Quel, Eduardo

    2013-01-01

    This paper discusses the multi-wavelength scanning Raman lidar being built at Lidar Division, CEILAP (CITEDEF-CONICET) in the frame of the Argentinean Cherenkov Telescope Array (CTA) collaboration to measure the spectral characteristics of the atmospheric aerosol extinction profiles to provide better transmission calculations at the future CTA site. This lidar emits short laser pulses of 7-9 ns at 355, 532 and 1064 nm at 50 Hz with nominal energy of 125 mJ at 1064 nm. This wavelengths are also used to retrieve the atmospheric (air, aerosol and clouds) backscattered radiation in the UV, VIS and IR ranges. Raman capabilities were added in the UV and VIS wavelengths to retrieve the spectral characteristics of the aerosol extinction and the water vapor profile. Due to the expected low aerosol optical depth of the future site, the short observation period as well as the extension of the observation, an enhanced collection area is required. This system uses six 40 cm f/2.5 newtonian telescopes to avoid dealing with...

  16. Diseases and remedies in modern city: environmental perspectives of argentinian eugenism between the mundial wars

    Directory of Open Access Journals (Sweden)

    Vallejo, Gustavo

    2007-06-01

    Full Text Available During the inter - war period it consolidate in Argentina a tendency to pathologize the modern city, understood like an ill organism that produced and was consequence phisical and moral decadency
    of its habitants. The interruption of external inmigration contributed with new information for a strategy of regeneration that tried to establish from eugenesics directed to articulate the populationism with the territorial distribution, in the certainty that counteracted country the evils that generated the life modern. The work reviews the impact of this ideology in the different spheres and the way in which has integrated the cultural politic of the fascism and taked part of the corpus with which the biotipology looked to give scientific legitimacy.

    Durante el período de entreguerras se consolidó en Argentina una tendencia a patologizar la ciudad moderna, entendida como un organismo enfermo que producía y a su vez era consecuencia de la decadencia física y moral de sus habitantes. La interrupción de la inmigración externa aportó nuevos datos para una estrategia de regeneración que pugnó por establecer, desde la eugenesia, medidas dirigidas a articular el poblacionismo con la distribución territorial, en la certeza de que el campo contrarrestaría los males que generaba la vida moderna. El trabajo repasa el impacto de esta ideología en distintas esferas y el modo en que ella se recepcionó junto a la política cultural del fascismo y formó parte del corpus con el que la biotipología buscó darle legitimidad científica.

  17. Argentinian Experience and Perspectives for Small and Medium Sized Reactors. Annex I

    International Nuclear Information System (INIS)

    The National Atomic Energy Commission (CNEA) was created on 31 May 1950. It was responsible for all nuclear activities in the country until 1994. In 1994, the regulatory body and the operational activities of nuclear power plants were separated. A utility named Nucleoelectrica Argentina (NASA) was created. The present missions of the CNEA are: - To assist the national Government in nuclear policy; - To provide research and development in nuclear areas, including nuclear power plants, research reactors and nuclear fuel cycles; - To provide spent fuel and radioactive waste management, decommissioning of nuclear and radioactive installations, and environmental remediation; - By itself or through related companies, to provide radioisotopes for medicine and industry, and provide services to nuclear power plants and conventional industries. Development of human resources is yet another important objective of CNEA activities

  18. Anticipatory motor patterns limit muscle stretch during landing in toads

    OpenAIRE

    Azizi, Emanuel; Abbott, Emily M.

    2013-01-01

    To safely land after a jump or hop, muscles must be actively stretched to dissipate mechanical energy. Muscles that dissipate energy can be damaged if stretched to long lengths. The likelihood of damage may be mitigated by the nervous system, if anticipatory activation of muscles prior to impact alters the muscle's operating length. Anticipatory motor recruitment is well established in landing studies and motor patterns have been shown to be modulated based on the perceived magnitude of the i...

  19. Sodium recirculation and isotonic transport in toad small intestine

    DEFF Research Database (Denmark)

    Nedergaard, Signe Nielsen; Larsen, Erik Hviid; Ussing, Hans H.

    1999-01-01

    Small intestine; leaky epithelia; solute-coupled water transport; Na*O+ recirculation; lateral intercellular space; flux ratio analysi......Small intestine; leaky epithelia; solute-coupled water transport; Na*O+ recirculation; lateral intercellular space; flux ratio analysi...

  20. Teaduslikud töötoad osutusid magnetiks / Martin Pau

    Index Scriptorium Estoniae

    Pau, Martin, 1975-

    2011-01-01

    Haridus- ja teadusministeeriumilt teaduse ja tehnoloogia populariseerimise eest preemia saanud maaülikooli doktorantide projekti «Elus teadus» õpitubades osales esimese kolme kuuga üle 800 koolilapse

  1. Disappearance of boreal toads in Colorado: A contaminant investigation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Population sizes of many, but not all, amphibian species have experienced declines on all six continents on which they occur (Phillips 1990, Vial and Saylor 1993)....

  2. Evolutionary reduction of developmental plasticity in desert spadefoot toads

    OpenAIRE

    Kulkarni, S.R.; Gómez-Mestre, Iván; Moskalik, C.L.; Storz, B.L.; Buchholz, D.R.

    2011-01-01

    Organisms vary their rates of growth and development in response to environmental inputs. Such developmental plasticity may be adaptive and positively correlate with environmental heterogeneity. However, the evolution of developmental plasticity among closely related taxa is not well understood. To determine the evolutionary pattern of plasticity, we compared plasticity in time to and size at metamorphosis in response to water desiccation in tadpoles among spadefoot species that differ in bre...

  3. Middle Breton prezeffan 'vermin, toad, lizard'

    DEFF Research Database (Denmark)

    Jørgensen, Anders Richardt

    2012-01-01

    Middelbretonsk prezeffan, hidtil set som en uforklaret variant af preffan 'kryb' (diminutiv af preff 'orm'), tolkes nu i stedet som et selvstændigt leksem. Det afledes af et ældre *pezreffan, som svarer direkte til kornisk pedrevan 'firben'. En videre analyse identificerer første del af ordet som...

  4. A Stylistic Analysis of Philip Larkin’s Toads

    Institute of Scientific and Technical Information of China (English)

    Fu Yanli

    2013-01-01

    This paper analyzes the stylistic features of the poem “Toads” written by Philip Larkin. This paper focuses on the stylistic features: lexis, grammar, rhetorical devices, phonetics and so on. At the end of this paper, some interpretations wil be made to il ustrate the importance of stylistics to poetry appreciation.

  5. All-Optical Reversible Hybrid New Gate using TOAD

    Directory of Open Access Journals (Sweden)

    Goutam Kumar Maity

    2014-03-01

    Full Text Available Reversible logic is emerged as a promising computing paradigm with applications in low-power CMOS, quantum computing, optical computing and nanotechnology. Optical logic gates become potential component to work at macroscopic (light pulses carry information, or quantum (single photon carries information levels with high efficiency. In this paper, we propose a novel scheme of Hybrid new gate realization in all-optical domain. Simulation results verify the functionality of the gate as well as reversibility. Approximate insertion power loss in dB is also reported for the Gaussian incident and control pulse.

  6. A new species of nematode (Molineidae) from Rhinella marina (Amphibia: Bufonidae) in Guerrero, México.

    Science.gov (United States)

    Ruiz-Torres, Nallely; García-Prieto, Luis; Osorio-Sarabia, David; Violante-González, Juan

    2013-06-01

    Oswaldocruzia lamotheargumedoi n. sp., inhabiting the intestine of the cane toad, Rhinella marina (L.), in Laguna de Coyuca, Guerrero, México, is described here. The new species differs from 10 congeners infecting bufonid hosts because it has a type I bursa. In contrast, 7 of these species have type II bursa and 3 more a type III bursa. The species most similar to the species described herein is Oswaldocruzia pipiens Walton, 1929 . These 2 species share traits such as body size, bursa type, presence of cervical alae, and dorsal ray morphology. Nevertheless, both species can be distinguished based on the number of synlophe ridges at mid-body (54-56 for O. lamotheargumedoi vs. 45-48 for O. pipiens) and by the presence of a chitinous support in the long, and well developed, cervical alae of O. pipiens. In the new species, these structures are short, poorly developed, and lack chitinous support. Previous records of species of Oswaldocruzia in México include Oswaldocruzia subauricularis (Rudolphi, 1819) Travassos, 1917 in the Neotropical Realm and O. pipiens in the Nearctic.

  7. A new species of the Rhinella margaritifera species group (Anura, Bufonidae) from the montane forest of the Selva Central, Peru.

    Science.gov (United States)

    Moravec, Jiří; Lehr, Edgar; Cusi, Juan Carlos; Córdova, Jesús H; Gvoždík, Václav

    2014-01-01

    We describe a new species of the bufonid toad genus Rhinella from transition montane forest of the buffer zones of the Yanachaga-Chemillén National Park and the Pui Pui Protected Forest (eastern slopes of Andes, Selva Central, Peru). The new species belongs to the Rhinella margaritifera species group (confirmed by mtDNA data) and differs from all its members by the absence of tympanic membrane and tympanic annulus. It is characterized by medium size (SVL 57.5-65.5 mm, n = 5), moderately developed cranial crests, absence of neural crest of vertebrae, absence of bone protrusion at angle of jaw, presence of lateral rows of enlarged tubercles, and absence of subgular vocal sac and vocal slits in males. In addition, based on the molecular phylogenetic analyses of selected Rhinella species we propose the monophylum containing R. chavin, R. festae, R. macrorhina, R. manu, R. nesiotes, R. rostrata, and R. yanachaga as a new species group under the name Rhinella festae species group. PMID:24493953

  8. A new species of the Rhinella margaritifera species group (Anura, Bufonidae from the montane forest of the Selva Central, Peru

    Directory of Open Access Journals (Sweden)

    Jiri Moravec

    2014-01-01

    Full Text Available We describe a new species of the bufonid toad genus Rhinella from transition montane forest of the buffer zones of the Yanachaga-Chemillén National Park and the Pui Pui Protected Forest (eastern slopes of Andes, Selva Central, Peru. The new species belongs to the Rhinella margaritifera species group (confirmed by mtDNA data and differs from all its members by the absence of tympanic membrane and tympanic annulus. It is characterized by medium size (SVL 57.5–65.5 mm, n = 5, moderately developed cranial crests, absence of neural crest of vertebrae, absence of bone protrusion at angle of jaw, presence of lateral rows of enlarged tubercles, and absence of subgular vocal sac and vocal slits in males. In addition, based on the molecular phylogenetic analyses of selected Rhinella species we propose the monophylum containing R. chavin, R. festae, R. macrorhina, R. manu, R. nesiotes, R. rostrata, and R. yanachaga as a new species group under the name Rhinella festae species group.

  9. The stabbing of Amelia (or how was extinguished the married women discrimination from the argentinian telephone service

    Directory of Open Access Journals (Sweden)

    Dora Barrancos

    2008-04-01

    Full Text Available This paper highlights the tracks of Amelia C. Her life story as switchboard is relevant to understand the women' s discrimination in laboral market in the early twentieth century. This article will be focused on the marital satatus as pattern of female exclusion. The strategy used by Amelia against that pattern, although individual and even desperate, detonated a series of revisions of existing legislation that were supported by different groups in society. The corpus is based on records of the telephone company in which Amelia was employed for several years and the impact of their strategies in the local press.

  10. Cuban-Argentinian Collaborative Exchange for the Implementation of a Virtual Space that Contributes to Teacher Training in Histology.

    OpenAIRE

    Samar, María Elena; de la C. Rodríguez Pérez, Irene; de J. Pomares Bory, Eduardo; Ávila, Rodolfo Esteban; Iglesias Ramírez, Belén Z.; Valenti Pérez, Jaime R.

    2011-01-01

    The Computer science's Technologies and the Communications, jointly with the Internet, offers an indispensable pedagogic tool for the education in our times when facilitating the collaborative integration of experiences and tacit knowledge that, stored in distant educational institutions, can be integrated in the conformation of an organizational atmosphere of common learning. From the year 2008 exist a Cuban-Argentinean collaborative exchange that connects the places web of our universities,...

  11. The origin of the gullwing-shaped cirrus above an Argentinian thunderstorm as seen in CALIPSO images

    Science.gov (United States)

    Wang, Pao K.; Cheng, Kai-Yuan; Setvak, Martin; Wang, Chen-Kang

    2016-04-01

    Gullwing-shaped cirrus layers are observed on an image above a severe thunderstorm occurred in Argentina taken by the instrument CALIOP on board of the CALIPSO satellite. The cirrus layers extended into a level in the stratosphere even higher than the above-anvil cirrus plumes that had been studied previously. This paper utilized the cloud model simulation results of a similar storm to explain the formation of such gullwing cirrus. It is shown that these cirrus layers can form from the moisture transported upward by successive internal gravity wave breaking at levels higher than the above-anvil plumes. The vertical locus of the wave crests where wave breaking occurs is itself gullwing-shaped which is the main reason why the thin cirrus layers are also gullwing shaped. Model results indicate that wave breaking can transport materials irreversibly into higher stratospheric layers and the gullwing-shaped cirrus is an evidence of this transport process.

  12. Fish assemblages in a small temperate estuary on the Argentinian coast: spatial variation, environmental influence and relevance as nursery area

    Directory of Open Access Journals (Sweden)

    Agustín Solari

    2015-09-01

    Full Text Available AbstractThe effects of different environmental variables on the fish community structure were evaluated in a small temperate estuary. The biological and environmental data were collected bimonthly between 2007 and 2009 along the main estuarine axis. Multivariate analyses were applied (CLUSTER, SIMPER, CCA to determine the spatial structure of fish community and to estimate the environmental influence on it. A total of 48 species of "teleost" fishes were observed, with the families Characidae and Sciaenidae presenting the largest number of species, 90% of the catches being juveniles. The fish community was overwhelmingly dominated by one species (Micropogonias furnieri, 88.9%, and only four species contributed more than 1% of total catch (Odontesthes argentinensis5.4%, Brevoortia aurea 1.1%, Paralonchurus brasiliensis 1.1%, and Mugil platanus 1.0%. Estuarine and freshwater stragglers dominated in number of species, followed by freshwater migrants and marine migrants. Three areas with different fish assemblages, with distinctive species and functional guilds, were defined along the main axis. The occurrence and spatial spread of these areas were linked to spatial variation in salinity, which was consistently influenced by discharge from the Río de la Plata and local precipitation. The results highlight the importance of shallow environments as nursery areas and permit emphasis on their susceptibility to environmental changes.

  13. Irony, Humour and Cynicism in Relation to Memory. A Contrastive Analysis between the Argentinian and the Mexican Literary Field

    NARCIS (Netherlands)

    Adriaensen, B.Y.A.

    2015-01-01

    Making fun of traumatic experiences is a delicate issue. However, Freud has worked on the cathartic function of the joke (1905), and Andréa Lauterwein, in her edited volume Rire, Mémoire, Shoah (2009) insisted on the presence and relevance of laughter in the memory of the Shoah. In the context of La

  14. Compatibility Relations Between the Edible Carrot Daucus Carota and D. Pusillus, a Related Wild Species from the Argentinian Pampas

    Science.gov (United States)

    To establish the feasibility of hybridization between the wild carrot species Daucus pusillus Michx. (2n = 2x = 22; 2n = 2x = 22 and 20), collected in the pampas grasslands of Argentina, and the edible carrot, Daucus carota L. (2n = 2x = 18), controlled pollinations were attempted on the plant. Due ...

  15. Late Glacial-Holocene climatic transition record at the Argentinian Andean piedmont between 33-34° S

    Science.gov (United States)

    Mehl, A. E.; Zárate, M. A.

    2013-10-01

    The Arroyo La Estacada (~33°28' S, 69°02' W), eastern Andean piedmont of Argentina, cuts through an extensive piedmont aggradational unit composed of a dominant late Pleistocene-early Holocene (LP-EH) alluvial sequence including several paleosols. The arroyo sedimentary record exhibits a paleosol developed affecting the topmost part of likely Lateglacial aeolian deposits aggraded into a floodplain environment by the end of the late Pleistocene. The paleosol shows variable grade of development in the outcrops along the arroyo probably in relation to fluvial valley paleotopography. Organic matter humification, carbonate accumulation and redox processes were the dominant processes associated with paleosol formation. By the early Holocene, when the formation of the paleosol ended, alluvial aggradation renewed and a higher frequency of flooding events could have affected the arroyo's floodplain environment. A period of relative landscape stability in the Arroyo La Estacada basin is inferred from the paleosol developed by the LP-EH transition in response to a climatic amelioration in the Andes cordillera piedmont after the Late Glacial arid conditions. The renewal of early Holocene alluvial aggradation was probably influenced by the South American Monsoon and resulted in a change in the sedimentary dynamics of the arroyo. The analyzed Late Glacial-Holocene alluvial record of the Andean piedmont constitutes a suitable record of the LP-EH climatic transition at the extra Andean region of Argentina. It is in agreement with regional paleoclimatic evidence along the southern tip of the South American continent, where other sedimentary sequences record similar late Quaternary paleoenvironmental changes over both fluvial and interfluvial areas.

  16. Drug-induced hepatotoxicity and tuberculosis in a hospital from the Argentinian northeast: cross-sectional study

    Directory of Open Access Journals (Sweden)

    Alfredo Sebastián Golemba

    2015-05-01

    Full Text Available INTRODUCCIÓN La hepatotoxicidad es un efecto adverso grave debido al tratamiento antituberculoso. OBJETIVOS El objetivo de este trabajo fue estimar la prevalencia, las formas de presentación y evolución de pacientes con hepatotoxicidad por antifímicos. MÉTODOS Se realizó un estudio observacional y descriptivo. Se incluyeron historias clínicas de pacientes mayores de 16 años, desde el 1 de enero de 2011 hasta el 30 junio de 2014 en el Servicio de Clínica Médica del Hospital Ángela I. de Llano, de Corrientes, Argentina. RESULTADOS Durante el período estudiado se diagnosticaron 118 pacientes con tuberculosis. El 7,6% (nueve pacientes, seis hombres y tres mujeres desarrolló hepatotoxicidad, de carácter hepatocelular en seis y colestásico en tres. La media de edad fue 34,6 años ± 14,3. Todos recibieron triple asociación y etambutol diariamente. Se los internó, en promedio 16 días (rango 4 a 37. Cuatro se encontraban asintomáticos, tres presentaron anorexia, náuseas y vómitos, y dos ictericia. El intervalo entre el inicio del tratamiento y la manifestación clínica fue en promedio de 9,6 días (rango 2 a 23. El intervalo entre el inicio y la suspensión del tratamiento fue en promedio 15,2 días (rango 3 a 48. Ninguno requirió trasplante hepático ni se registró ningún óbito. CONCLUSIONES La hepatotoxicidad por antifímicos se ha asociado a factores como edad mayor de 35 años, sexo femenino, embarazo, desnutrición, alcoholismo, presencia de virus de la inmunodeficiencia humana, hepatopatía previa, tratamiento diario, diabetes, insuficiencia renal, tratamiento combinado. Debido a la escasez de registros regionales, esta casuística podría ser el inicio para la creación de registros, a nivel regional y/o nacional, de efectos adversos, el establecimiento de programas de farmacovigilancia que contribuyan a la búsqueda activa de esta complicación, y el desarrollo de guías para unificar conceptos y protocolos de tratamiento específicos.

  17. Genetic Diversity and Population Structure in South African, French and Argentinian Angora Goats from Genome-Wide SNP Data.

    Directory of Open Access Journals (Sweden)

    Carina Visser

    Full Text Available The Angora goat populations in Argentina (AR, France (FR and South Africa (SA have been kept geographically and genetically distinct. Due to country-specific selection and breeding strategies, there is a need to characterize the populations on a genetic level. In this study we analysed genetic variability of Angora goats from three distinct geographical regions using the standardized 50k Goat SNP Chip. A total of 104 goats (AR: 30; FR: 26; SA: 48 were genotyped. Heterozygosity values as well as inbreeding coefficients across all autosomes per population were calculated. Diversity, as measured by expected heterozygosity (HE ranged from 0.371 in the SA population to 0.397 in the AR population. The SA goats were the only population with a positive average inbreeding coefficient value of 0.009. After merging the three datasets, standard QC and LD-pruning, 15 105 SNPs remained for further analyses. Principal component and clustering analyses were used to visualize individual relationships within and between populations. All SA Angora goats were separated from the others and formed a well-defined, unique cluster, while outliers were identified in the FR and AR breeds. Apparent admixture between the AR and FR populations was observed, while both these populations showed signs of having some common ancestry with the SA goats. LD averaged over adjacent loci within the three populations per chromosome were calculated. The highest LD values estimated across populations were observed in the shorter intervals across populations. The Ne for the Angora breed was estimated to be 149 animals ten generations ago indicating a declining trend. Results confirmed that geographic isolation and different selection strategies caused genetic distinctiveness between the populations.

  18. Molecular typing of Argentinian Mycobacterium avium subsp. paratuberculosis isolates by multiple-locus variable number-tandem repeat analysis

    Directory of Open Access Journals (Sweden)

    Andrea Gioffré

    2015-06-01

    Full Text Available Multiple-locus variable number-tandem repeat analysis (MLVA of Mycobacterium avium subspecies paratuberculosis (MAP isolates may contribute to the knowledge of strain diversity in Argentina. Although the diversity of MAP has been previously investigated in Argentina using IS900-RFLP, a small number of isolates were employed, and a low discriminative power was reached. The aim of the present study was to test the genetic diversity among MAP isolates using an MLVA approach based on 8 repetitive loci. We studied 97 isolates from cattle, goat and sheep and could describe 7 different patterns: INMV1, INMV2, INMV11, INMV13, INMV16, INMV33 and one incomplete pattern. INMV1 and INMV2 were the most frequent patterns, grouping 76.3% of the isolates. We were also able to demonstrate the coexistence of genotypes in herds and co-infection at the organism level. This study shows that all the patterns described are common to those described in Europe, suggesting an epidemiological link between the continents.

  19. Molecular typing of Argentinian Mycobacterium avium subsp. paratuberculosis isolates by multiple-locus variable number-tandem repeat analysis.

    Science.gov (United States)

    Gioffré, Andrea; Correa Muñoz, Magnolia; Alvarado Pinedo, María F; Vaca, Roberto; Morsella, Claudia; Fiorentino, María Andrea; Paolicchi, Fernando; Ruybal, Paula; Zumárraga, Martín; Travería, Gabriel E; Romano, María Isabel

    2015-06-01

    Multiple-locus variable number-tandem repeat analysis (MLVA) of Mycobacterium avium subspecies paratuberculosis (MAP) isolates may contribute to the knowledge of strain diversity in Argentina. Although the diversity of MAP has been previously investigated in Argentina using IS900-RFLP, a small number of isolates were employed, and a low discriminative power was reached. The aim of the present study was to test the genetic diversity among MAP isolates using an MLVA approach based on 8 repetitive loci. We studied 97 isolates from cattle, goat and sheep and could describe 7 different patterns: INMV1, INMV2, INMV11, INMV13, INMV16, INMV33 and one incomplete pattern. INMV1 and INMV2 were the most frequent patterns, grouping 76.3% of the isolates. We were also able to demonstrate the coexistence of genotypes in herds and co-infection at the organism level. This study shows that all the patterns described are common to those described in Europe, suggesting an epidemiological link between the continents. PMID:26273274

  20. Genetic Diversity and Population Structure in South African, French and Argentinian Angora Goats from Genome-Wide SNP Data.

    Science.gov (United States)

    Visser, Carina; Lashmar, Simon F; Van Marle-Köster, Este; Poli, Mario A; Allain, Daniel

    2016-01-01

    The Angora goat populations in Argentina (AR), France (FR) and South Africa (SA) have been kept geographically and genetically distinct. Due to country-specific selection and breeding strategies, there is a need to characterize the populations on a genetic level. In this study we analysed genetic variability of Angora goats from three distinct geographical regions using the standardized 50k Goat SNP Chip. A total of 104 goats (AR: 30; FR: 26; SA: 48) were genotyped. Heterozygosity values as well as inbreeding coefficients across all autosomes per population were calculated. Diversity, as measured by expected heterozygosity (HE) ranged from 0.371 in the SA population to 0.397 in the AR population. The SA goats were the only population with a positive average inbreeding coefficient value of 0.009. After merging the three datasets, standard QC and LD-pruning, 15 105 SNPs remained for further analyses. Principal component and clustering analyses were used to visualize individual relationships within and between populations. All SA Angora goats were separated from the others and formed a well-defined, unique cluster, while outliers were identified in the FR and AR breeds. Apparent admixture between the AR and FR populations was observed, while both these populations showed signs of having some common ancestry with the SA goats. LD averaged over adjacent loci within the three populations per chromosome were calculated. The highest LD values estimated across populations were observed in the shorter intervals across populations. The Ne for the Angora breed was estimated to be 149 animals ten generations ago indicating a declining trend. Results confirmed that geographic isolation and different selection strategies caused genetic distinctiveness between the populations. PMID:27171175

  1. Obesity, overweight and socioeconomic conditions. The Argentinian CASE Obesidad, sobrepeso y condiciones socioeconómicas. El caso argentino

    Directory of Open Access Journals (Sweden)

    Valentina Viego

    2012-06-01

    Full Text Available Obesity has been classified by the World Health Organization as a worldwide epidemic. This issue is a growing field in economics due to pathologies associated with overweight, the significant impact on healthcare costs and consequent deterioration of welfare. This paper shows the analysis of the results from the National Survey of Risk Factors in order to identify the role of socioeconomic conditions of obesity and overweight based on panel data models. The results indicate that the income level and sedentary lifestyle have positively influenced obesity and overweight, whereas the education and medical coverage are not relevant when explaining the differences between provinces in overweight prevalence, but become significant in the obesity rates variationsLa obesidad ha sido clasificada por la OMS como epidemia mundial. Su estudio ocupa un lugar destacado en la Economía de la Salud debido a su impacto sobre los costos sanitarios y deterioro de la calidad de vida. El objetivo de este trabajo es analizar los resultados de la Encuesta Nacional de Factores de Riesgo estableciendo la incidencia de las condiciones socioeconómicas sobre indicadores de obesidad y sobrepeso en las provincias  argentinas. Se estimó un modelo con datos de panel donde el indicador testigo de la proporción de población con problemas de peso depende de variables socioeconómicas y de variables de conducta. Los resultados indican que el nivel de ingreso y el sedentarismo tienen una influencia positiva sobre la obesidad y el sobrepeso mientras que la educación y la cobertura médica no resultan relevantes en la explicación de las diferencias entre provincias en la proporción de población con sobrepeso, pero sí se vuelven significativas para explicar las variaciones en la tasa de obesidad

  2. Psychometric properties of the attitudes toward gay men scale in Argentinian context: The influence of sex, authoritarianism, and social dominance orientation

    Directory of Open Access Journals (Sweden)

    Edgardo Etchezahar

    2016-01-01

    Full Text Available Even though prejudice toward male homosexuality is one of the main reasons for discrimination in Argentina, there is no valid measure to assess it. The aim of this study was to analyze the psychometric properties of the Attitudes Toward Gay Men Scale (ATG and to examine the influence of sex, right wing authoritarianism, and social dominance orientation on anti-gay attitudes. Data were collected with a convenience sample of 436 undergraduate students from University of Buenos Aires. Analysis of the data showed adequate psychometric properties for the ATG Scale and the moderating effect of sex, right wing uthoritarianism and social dominance orientation on anti-gay attitudes. Implications of these findings were discussed.

  3. Short-term evaluation of the impact of a fortified food aid program on the micronutrient nutritional status of Argentinian pregnant women.

    Science.gov (United States)

    Malpeli, Agustina; Ferrari, María Guillermina; Varea, Ana; Falivene, Mariana; Etchegoyen, Graciela; Vojkovic, María; Carmuega, Estéban; Disalvo, Liliana; Apezteguía, María; Pereyras, Silvia; Tournier, Andrea; Vogliolo, Daniel; Gonzalez, Horacio F

    2013-11-01

    We studied the impact of a food supplementation program (Plan Más Vida (PMV)) on the micronutrient nutritional condition of pregnant women from low-income families 1 year after its implementation. The food program provided supplementary diet (wheat and maize--fortified flour, rice or sugar, and fortified soup). We performed a prospective, nonexperimental, cross-sectional study in the province of Buenos Aires, Argentina, evaluating pregnant women at baseline (n = 164) and 1 year after PMV implementation (n = 108). Biochemical tests (hemogram, ferritin, vitamin A, zinc, and folic acid), anthropometric assessments (weight and height), and dietary surveys (24 h recall) were performed at the two study points. One year after PMV implementation, no significant changes in anthropometric values were observed. Folic acid deficiency and the risk of vitamin A deficiency (retinol, 20-30 μg/dl) decreased significantly (35.8 to 6.1 % and 64 to 41 %, respectively; p nutritional strategies had a high impact on the prevalence of folic acid deficiency. We also observed a decrease in the risk of vitamin A deficiency, and no impact on iron and zinc nutritional status. Adherence to the specific fortified food (soup) was not good and intra-family dilution and distribution of food was high. PMID:23999776

  4. Management of Protected Areas and Its Effect on an Ecosystem Function: Removal of Prosopis flexuosa Seeds by Mammals in Argentinian Drylands

    Science.gov (United States)

    Campos, Valeria E.; Miguel, Florencia; Cona, Mónica I.

    2016-01-01

    The ecological function of animal seed dispersal depends on species interactions and can be affected by drivers such as the management interventions applied to protected areas. This study was conducted in two protected areas in the Monte Desert: a fenced reserve with grazing exclusion and absence of large native mammals (the Man and Biosphere Ñacuñán Reserve; FR) and an unfenced reserve with low densities of large native and domestic animals (Ischigualasto Park; UFR). The study focuses on Prosopis flexuosa seed removal by different functional mammal groups: “seed predators”, “scatter-hoarders”, and “opportunistic frugivores”. Under both interventions, the relative contribution to seed removal by different functional mammal groups was assessed, as well as how these groups respond to habitat heterogeneity (i.e. vegetation structure) at different spatial scales. Camera traps were used to identify mammal species removing P. flexuosa seeds and to quantify seed removal; remote sensing data helped analyze habitat heterogeneity. In the FR, the major fruit removers were a seed predator (Graomys griseoflavus) and a scatter-hoarder (Microcavia asutralis). In the UFR, the main seed removers were the opportunistic frugivores (Lycalopex griseus and Dolichotis patagonum), who removed more seeds than the seed predator in the FR. The FR shows higher habitat homogeneity than the UFR, and functional groups respond differently to habitat heterogeneity at different spatial scales. In the FR, because large herbivores are locally extinct (e.g. Lama guanicoe) and domestic herbivores are excluded, important functions of large herbivores are missing, such as the maintenance of habitat heterogeneity, which provides habitats for medium-sized opportunistic frugivores with consequent improvement of quality and quantity of seed dispersal services. In the UFR, with low densities of large herbivores, probably one important ecosystem function this group performs is to increase habitat heterogeneity, allowing for the activity of medium-sized mammals who, behaving as opportunistic frugivores, did the most significant seed removal. PMID:27655222

  5. The Kapelusz publisher proposal for the Argentinian primary school: a quantitative and qualitative analysis of 4th year manuals in the Social Sciences area, 1976-2001

    OpenAIRE

    Romina De Luca

    2015-01-01

    The article is a contribution to the field of studies on textbooks. It analyzes the changes and continuities recorded in the “comprehensive manuals” by the Kapelusz publisher for the elementary education in Argentina between 1976 and 2001. A sample of manuals for the fourth grade published by that publisher is analyzed. The contents of social sciences, specifically History, are reviewed here. The article analyzes the changes in the manuals and their evolution is compared at the in...

  6. Writings, politics and human rights of the children of the Argentinian desaparecidos: new identities in Los topos and Las chanchas by Félix Bruzzone

    Directory of Open Access Journals (Sweden)

    Camilla Cattarulla

    2015-11-01

    Full Text Available After tracing the main points shaping the debate on human rights, history, memory, testimony and politics which took place in Argentina starting from the end of the last military dictatorship (1976-1983, this article will deal with the writings of the children of the desaparecidos, focussing in particular on Félix Bruzzone’s novels Los topos (2008 and Las chanchas (2014. I will propose a reading of these texts which highlights the tension between a fate seemingly decided by the actual collective memory and the capacity to modify it, thus taking distance from the canonical literature of testimony and pointing towards new kinds of identities.

  7. “All men were born in Jerusalem”. Mith and gospel in the stories about the origen of humans among the toba (Qom of the Argentinian Chaco

    Directory of Open Access Journals (Sweden)

    Florencia Carmen Tola

    2011-12-01

    Full Text Available Parallelisms between stories of biblical inspiration and myths that describe the origins of the human beings, their corporal transformations and the differences between diverse types of beings can be found in contemporary narrations of the Toba people (Qom of the Argentinean Gran Chaco. Events described in the Bible are usually spun with elements of the mythical past of Toba people, therefore generating a biblical reading of the indigenous past and new readings on the human origins, of the differences between beings and of the importance of the body in the constitution of human specificity. This paper examines some of these narrations where myths and Biblical stories are interlaced giving rise to new notions of body and person.

  8. α6β4 Integrin Genetic Variations (A380T and R1281W) and Breast Cancer Risk in an Argentinian Population

    Science.gov (United States)

    Acosta, Karina Beatriz; Lorenzini Campos, Melina Noelia; Etcheverry, Susana Beatriz; Zapata, Pedro Dario

    2016-01-01

    The α6β4 integrin is composed of the α6 and β4 subunits that are encoded by the ITGα6 and the ITGβ4 genes, respectively. The α6β4 main function is to intervene in lamination and epithelia integrity maintenance by cell-matrix interactions. This integrin appears to have importance in breast cancer malignancy, as well as other epithelial carcinomas. The aim of this work was to investigate the potential role of ITGα6 (A380T) and ITGβ4 (R1281W) genetic variations in breast cancer susceptibility, in a female population from the northeast region of Argentina (Misiones). We performed a case-control study of 85 breast cancer patients and 113 cancer-free controls. Genotyping was performed by RFLP-PCR. For ITGα6 (A380T) single nucleotide polymorphism, a high frequency of heterozygous genotype GA in cases compared to controls was observed, achieving values of 48% and 49%, respectively. No association between the A380T SNP and breast cancer development was found (Odds Ratio = 0.92; 95% Confidence Interval = 0.52–1.63; p = 0.884). In conclusion, we did not find evidence of an association between A380T (ITGα6) and the risk of developing breast cancer. The results represent the first report of these genetic variations in breast cancer; therefore, they are an important contribution to the literature. PMID:27763564

  9. The dynamics of venous return and response to hypervolemia in the toad, Bufo marinus (L.)

    OpenAIRE

    Killorn, Erin E; Toews, Daniel P

    2001-01-01

    Background Venous return from the posterior region of amphibians travels by either two renal portal veins to the kidney or a central abdominal vein that drains into the hepatic portal system. The relative proportions of blood flow in these vessels has never been measured nor has a modification of flow been determined when venous return increases by changes in blood volume during hypervolemia or during increased volume input from the posterior lymph hearts. Results Venous return from the poste...

  10. Properties of a conductive cellular chloride pathway in the skin of the toad (Bufo bufo)

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Kristensen, P

    1978-01-01

    of the steady-state conductance and the steady-state chloride current reveal that the chloride pathway has maximum conductance for V approximately -80 mV (outside of the skin being negative) and approaches a non-conducting safe for V greater than 0 mV. This strong outward going rectification is a steady......-compartment model indicate that the strong steady-state chloride current rectification cannot be obtained if only the intracellular chloride concentration and the membrane potentials are allowed to vary ("Goldman-rectification"). It is suggested, therefore, that the premeability of the chloride pathway varies...

  11. Membrane potential plays a dual role for chloride transport across toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Rasmussen, B E

    1983-01-01

    -dependent currents are not caused by a trivial Goldmand-type rectification and ion redistributions following transepithelial potential pertubations. Extended with a dynamic Cl- permeability in the apical membrane according to a Hodgkin-Huxley kinetic scheme, the model predicts voltage clamp data which closely...

  12. Watch Out for the Under Toad : Role and Method of Interdisciplinary Contextualisation in Comparative Legal Research

    NARCIS (Netherlands)

    E. Mak (Elaine)

    2015-01-01

    textabstractThis article studies the significance of insights from non- legal disciplines (such as political science, economics, and sociology) for comparative legal research and the methodology connected with such ‘interdisciplinary contextualisation’. Based on a theoretical analysis concerning the

  13. NHE-1 sequence and expression in toad, snake and fish red blood cells

    DEFF Research Database (Denmark)

    Thomsen, Steffen Nyegaard; Wang, Tobias; Kristensen, Torsten

    Red blood cells (RBC) from reptiles appear not to express regulatory volume increase (RVI) upon shrinkage (Kristensen et al., 2008). In other vertebrates, the RVI response is primarily mediated by activation of the Na+/H+ exchanger (NHE-1) and we, therefore decided to investigate whether red cell...

  14. Use of oxytetracycline in batch-marking post-metamorphic boreal toads

    Science.gov (United States)

    Muths, E.; Corn, P.S.; Stanley, T.R.

    2000-01-01

    Comparison of organochlorine residues in wildlife must often be made to regulatory standards or to values of known biological significance; this is difficult when dissimilar tissues are analyzed and results are expressed on different bases. To relate levels in the different tissues used for regulatory and monitoring purposes and for biological assessments, we exposed American black ducks to mixtures of three organochlorines. Differences in residue burdens among tissues were not statistically significant when levels were expressed on a lipid weight basis. Levels of heptachlor and Aroclor 1254 in one tissue can be accurately predicted from those in another; such predictions for endrin are less reliable. Lipid weight based residue concentrations in wings may be used to predict whether levels in fat exceed residue standards set for human health or approach those associated with effects on populations of species sampled.

  15. Cane Toad or Computer Mouse? Real and Computer-Simulated Laboratory Exercises in Physiology Classes

    Science.gov (United States)

    West, Jan; Veenstra, Anneke

    2012-01-01

    Traditional practical classes in many countries are being rationalised to reduce costs. The challenge for university educators is to provide students with the opportunity to reinforce theoretical concepts by running something other than a traditional practical program. One alternative is to replace wet labs with comparable computer simulations.…

  16. Amiloride inhibits mammalian renal kallikrein and a kallikrein-like enzyme from toad bladder and skin.

    OpenAIRE

    Margolius, H S; Chao, J.

    1980-01-01

    Renal kallikrein is localized in luminal plasma membranes of the mammalian distal nephron and gains access to urine from this site. Its activity is regulated, in part, by aldosterone. These facts led us to study the effects of amiloride, a drug known to inhibit sodium reabsorption and potassium secretion at this site, on kallikrein activity. Amiloride inhibited the esterolytic activity of purified rat or human urinary kallikrein or of rat renal cortical cells upon a synthetic substrate (ID50 ...

  17. Influence of dissolved oxygen conditions on toxicity of ammonium nitrate to larval natterjack toads.

    Science.gov (United States)

    Ortiz-Santaliestra, Manuel E; Marco, Adolfo

    2015-07-01

    Temporary ponds, where many amphibians from temperate regions breed, show an annual cycle with a maximum water volume in spring followed by a progressive desiccation throughout late spring and summer. This desiccation leads to a decrease in dissolved oxygen and an increase in nitrogen levels, which can additionally increase because of anthropogenic sources such as chemical fertilizers. We analyzed the toxicity posed by environmentally relevant levels of a common nitrogenous fertilizer, ammonium nitrate, at different conditions of oxygen availability to Bufo calamita tadpoles, which typically develop in ephemeral ponds. Ammonium nitrate (90.3 mg N-NO3NH4/l) and hypoxic conditions (initial dissolved oxygen 4.53 ± 0.40 mg/l) caused significant lethal effects after 7 and 12 days of exposure, respectively. At the end of experiment (16 days), mortality rates were 32.5 % in individuals exposed to the fertilizer and 15 % in those growing under hypoxic conditions. When both stressors were combined, they showed an additive effect on tadpole survival. Malformations, such as oedemas and spinal curvatures, and locomotory abnormalities, were detected after 12 days of experiment in >90 % of individuals exposed to 45.2 mg N-NO3NH4/l under hypoxic conditions, whereas none of these stressors by separate related to abnormality rates >35 %. Delayed development was also observed in tadpoles exposed to ammonium nitrate with hypoxia affecting developmental rate only after 12 days of exposure. The results are discussed in terms of potential mechanisms linking negative effects of both factors as well as in terms of potential alterations of the ecological plasticity that often allows amphibians to survive in unpredictable environments. PMID:25586169

  18. 75 FR 37358 - Endangered and Threatened Wildlife and Plants; Revised Critical Habitat for the Arroyo Toad

    Science.gov (United States)

    2010-06-29

    ... 7 percent discount rate. Overall, the real estate industry (real estate development, CEQA, and delay... present value terms using a 7 percent discount rate. Overall, the real estate industry (real estate... following categories: (1) Real estate development; (2) changes in water supply; (3) grazing activities;......

  19. Chloride transport in toad skin (Bufo viridis). The effect of salt adaptation

    DEFF Research Database (Denmark)

    Katz, U; Larsen, Erik Hviid

    1984-01-01

    ). for V = -50 mV the transepithelial Cl- conductance calculated from isotope flux measurements was 2.5 +/- 0.3 mS cm-2, N = 10. When the skin was clamped at + 50 mV the net flux of Cl- was reversed, but Cl- conductance was only 0.3 +/- 0.1 mScm-2. Flux ratio analysis indicated that the potential...

  20. Adverse effect of agroecosystem pond water on biological endpoints of common toad (Rhinella arenarum) tadpoles.

    Science.gov (United States)

    Babini, María Selene; Bionda, Clarisa de Lourdes; Salas, Nancy Edith; Martino, Adolfo Ludovico

    2016-08-01

    Chemical prroducts used in farming and wastes from livestock can contaminate pond water in agroecosystems due to runoff. Amphibians using these ponds for breeding are probably exposed to pollutants, and serious consequences might be observed afterward at the population level. Assessment biological endpoints of anuran to water quality give a realistic estimate of the probability of occurrence of adverse effects and provide an early warning signal. In this study, the ecotoxicity of agroecosystem ponds from the south of Córdoba province, Argentina, was investigated. Ponds in four sites with different degrees of human disturbance were selected: three agroecosystems (A1, A2, A3) and a site without crops or livestock (SM). The effect of pond water quality on the biological endpoint of Rhinella arenarum tadpoles was examined using microcosms with pond water from sites. Biological endpoints assessed were as follows: mortality, growth, development, morphological abnormalities (in body shape, gut, and labial tooth row formula), behavior, and blood cell parameters (micronucleus and nuclear abnormalities). Results indicated that water from agroecosystems has adverse effect on early life stage of R. arenarum. High mortality and fewer metamorphs were recorded in the A1 and A3 treatments. Tadpoles and metamorphs from A1 and A2 treatments had lower body condition. Tadpoles from A1 and A3 showed the highest prevalence of morphological abnormalities. The lowest amount of tadpoles feeding and the highest percentage of tadpoles swimming on the surface were observed in treatments with agroecosystem pond water. The higher frequencies of micronuclei and nuclear abnormalities were recorded in tadpoles from A1, A2, and A3 treatments. We check the sensitivity of the biological endpoints of R. arenarum tadpoles like early warning indicators of water quality. We found that the poor water quality of agroecosystem ponds has impact on the health of the tadpoles, and this could affect the persistence of populations. We recommend implementation of management actions before the harmful effects of agroecosystem pond water on early life stage of anuran become evident in higher ecological levels. PMID:27395360

  1. A new species of arboreal toad (Anura : Bufonidae : Chaunus) from Madidi National Park, Bolivia

    Science.gov (United States)

    Padial, J.M.; Reichle, S.; McDiarmid, R.; De la Riva, I.

    2006-01-01

    A new arboreal species of the Chaunus veraguensis group is described for the humid montane forest of Madidi National Park, in northern Bolivia. The new species differs from other species in the group by the combination small size, long and slender extremities, webbed hands, conspicuous tympanic membrane, well developed parotoid glands, absence of large glands on dorsum and extremities, nuptial excrescences of males composed of pungent spines on dorsal surface of thumb, greenish-brown coloration on dorsum with red warts in life, and green iris. It is only known from two nearby localities in the Serran Eslabon, Department La Paz. An operational key for species in the C. veraguensis group is provided.

  2. Soil Organic Matter Content Effects on Dermal Pesticide Bioconcentration in American Toads (Bufo Americanus)

    Science.gov (United States)

    Agricultural landscapes serve as active amphibian breeding grounds despite their seemingly poor habitat value. Activity of adults and dispersal of metamorphs to and from agricultural ponds occurs in most species from spring through late summer or early fall, a time that coincides...

  3. Integrating Multiple Distribution Models to Guide Conservation Efforts of an Endangered Toad

    OpenAIRE

    Treglia, Michael L.; Fisher, Robert N.; Fitzgerald, Lee A.

    2015-01-01

    Species distribution models are used for numerous purposes such as predicting changes in species' ranges and identifying biodiversity hotspots. Although implications of distribution models for conservation are often implicit, few studies use these tools explicitly to inform conservation efforts. Herein, we illustrate how multiple distribution models developed using distinct sets of environmental variables can be integrated to aid in identification sites for use in conservation. We focus on th...

  4. Comparative pathology and ecological implications of two myxosporean parasites in native Australian frogs and the invasive cane toad.

    Directory of Open Access Journals (Sweden)

    Ashlie Hartigan

    Full Text Available Myxosporean parasites Cystodiscus axonis and C. australis are pathogens of native and exotic Australian frog species. The pathology and ecological outcomes of infection with these parasites were investigated in this study. Gliosis was correlated to Cystodiscus axonis plasmodia in the brains of (9/60 tadpoles and (3/9 adult endangered Green and golden bell frogs using ordinal regression. Severe host reactions to C. axonis (haemorrhage, necrosis, and vasulitis were observed in the brains of threatened Southern bell frogs (8/8, critically endangered Booroolong frogs (15/44 and Yellow spotted bell frogs (3/3. Severe brain lesions were associated with behavioural changes, neurological dysfunction, and spontaneous death. Both C. axonis and C. australis develop in the bile ducts of tadpoles, the plasmodia were significantly associated with biliary hyperplasia, inflammation and the loss of hepatocytes in (34/72 Green and golden bell frog tadpoles using ordinal regression. These lesions were so severe that in some cases 70% of the total liver was diseased. Normal liver function in tadpoles is necessary for metamorphosis, metabolism, and immune function. We postulate that this extensive liver damage would have significant host health impacts. Severe hepatic myxosporidiosis was more prevalent in tadpoles examined in autumn and winter (overwintered, suggestive of delayed metamorphosis in infected tadpoles, which would have serious flow-on effects in small populations. We compared the sensitivity of histopathology and species-specific PCR in the detection of C. australis and C. axonis. PCR was determined to be the most sensitive method (detection limit 1 myxospore equivalent of ribosomal DNA. Histology, however, had the advantage of assessing the impact of the parasite on the host. It was concluded that these parasites have the potential for significant ecological impacts, because of their high prevalence of infection and their ability to cause disease in some frogs.

  5. JUVENILE WESTERN TOADS, BUFO BOREAS, AVOID CHEMICAL CUES OF SNAKES FED JUVENILE, BUT NOT LARVAL, CONSPECIFICS. (U915529)

    Science.gov (United States)

    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...

  6. 76 FR 70479 - Draft Environmental Assessment and Safe Harbor Agreement for the Houston Toad Within Nine Texas...

    Science.gov (United States)

    2011-11-14

    ... types that occur on the portion of the property to be enrolled, including ] accurate descriptions of vegetation, water features, and soil types; (4) current land use practices and existing development; and (5.... Box 1306, Albuquerque, New Mexico 87103 (505) 248-6651). SUPPLEMENTARY INFORMATION: Under a...

  7. The role of common toads in the winter diet of recolonising Eurasian otters (Lutra lutra

    Directory of Open Access Journals (Sweden)

    Pablo García-Díaz

    2011-02-01

    Full Text Available Importanza del rospo comune nella dieta invernale di una popolazione di lontra (Lutra lutra in espansione.
    Tramite analisi dei resti fecali, abbiamo evidenziato il ruolo fondamentale degli anfibi nella dieta invernale della lontra Lutra lutra in stagni artificiali della Spagna nord-occidentale. I numerosi “laghi di cava” presenti nell’area umida di Ribeiras do Louro e Gandaras de Budiño sono stati monitorati nel 2007-2009. Il rospo comune (Bufo bufo era la principale preda della lontra, costituendo l’88% della biomassa consumata, mentre il gambero americano Procambarus clarkii e i pesci erano prede secondarie. I nostri risultati contrastano con la ben nota preferenza della lontra per le rane rispetto al rospo. Il mantenimento della popolazione di lontra nel bacino del fiume Louro dipende strettamente dalla corretta gestione degli stagni artificiali.

  8. Effects of a fungicide formulation on embryo-larval development, metamorphosis, and gonadogenesis of the South American toad Rhinella arenarum.

    Science.gov (United States)

    Svartz, Gabriela; Meijide, Fernando; Pérez Coll, Cristina

    2016-07-01

    Sublethal toxicity of the formulated fungicide Maxim(®) XL on embryonic, larval and juvenile development of Rhinella arenarum was evaluated by means of standardized bioassays. Maxim(®) XL, one of the most used fungicides in Argentina, is based on a mixture of two active ingredients: Fludioxonil and Metalaxyl-M. Maxim(®) XL exposure induced severe sublethal effects on the embryos, expressed as general underdevelopment, axial flexures, microcephaly, cellular dissociation, abnormal pigmentation, underdeveloped gills, marked edema and wavy tail. As the embryo development advanced, alterations in behavior as spasmodic contractions, general weakness and inanition were observed. Maxim(®) XL did not affect neither the time required to complete metamorphosis nor sex proportions, but gonadal development and differentiation were impaired. Gross gonadal analysis revealed a significant proportion of exposed individuals with underdevelopment of one or both gonads. Histological analysis confirmed that 18% and 10% of the individuals exposed to 0.25 and 2mg/L Maxim(®) XL, respectively, exhibited undifferentiated gonads characterized by a reduced number (or absence) of germ cells. Taking into account the risk evaluation performed by means of Hazard Quotients, this fungicide could be a threat to R. arenarum populations under chronic exposure. This study represents the first evidence of toxic effects exerted by Maxim(®) XL on amphibians. Finally, our findings highlight the properties of this fungicide that might jeopardize non-target living species exposed to it in agricultural environments. PMID:27214195

  9. The dynamics of venous return and response to hypervolemia in the toad, Bufo marinus (L.)

    OpenAIRE

    Toews Daniel P; Killorn Erin E

    2001-01-01

    Abstract Background Venous return from the posterior region of amphibians travels by either two renal portal veins to the kidney or a central abdominal vein that drains into the hepatic portal system. The relative proportions of blood flow in these vessels has never been measured nor has a modification of flow been determined when venous return increases by changes in blood volume during hypervolemia or during increased volume input from the posterior lymph hearts. Results Venous return from ...

  10. Beta-adrenergic activation of solute coupled water uptake by toad skin epithelium results in near-isosmotic transport

    DEFF Research Database (Denmark)

    Nielsen, Robert; Larsen, Erik Hviid

    2007-01-01

    of [Na+]out in agreement with Na+ self-inhibition of ENaC. Ouabain on the inside decreased I(SC)(Eqv) from 60+/-10 to 6.1+/-1.7 microA cm(-2), and J(V) from 3.34+/-0.47 to 1.40+/-0.24 nL cm(-2) x s(-1). Short-circuited preparations exhibited a linear relationship between short-circuit current and J...

  11. Biomarker Analysis of American Toad (Anaxyrus Americanus) and Grey Tree Frog (Hyla Versicolor) Tadpoles Following Exposure to Atrazine

    Science.gov (United States)

    To better understand the mode of action of atrazine in amphibians, we utilized mass spectrometry-based metabolomics to investigate the biochemical changes in two species of larval amphibians exposed to atrazine. Our objectives were to 1) Use changes in endogenous metabolites to f...

  12. Tracking Amendments to Legislation and Other Political Texts with a Novel Minimum-Edit-Distance Algorithm: DocuToads

    DEFF Research Database (Denmark)

    Hermansson, Henrik Alf Jonas; Cross, James

    2015-01-01

    Political scientists often nd themselves tracking amendments to political texts. As different actors weigh in, texts change as they are drafted and redrafted, reflecting political preferences and power. This study provides a novel solution to the problem of detecting amendments to political text......) and substantive amount of amendments made between version of texts. To illustrate the usefulness and eciency of the approach we replicate two existing studies from the field of legislative studies. Our results demonstrate that minimum edit distance methods can produce superior measures of text amendments to hand...

  13. Wyoming toad, Bufo hemiophrys baxteri, habitat use and hibernaculum research project with the use of telemetry : Annual report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual report is on a two year study, started in 1998, to evaluate the daily and seasonal habitat use to determine the location of the hibemaculum of the...

  14. Mechanisms of adreno- and cholinoreceptors in isolated pulmonary and systemic vasculature of the cane toad (Rhinella marina)

    DEFF Research Database (Denmark)

    Pedersen, Pil Birkefeldt Møller; Wang, Tobias; Brøndum, Emil Toft

    site of regulation of resistance and therefore holds the capacity to control blood flow and pressure. This vascular control allows amphibians to regulate their shunt, i.e. partially bypassing either the pulmonary or systemic circuit. Shunting in amphibians has been studied due to their multiple...

  15. Responses on toad tadpoles to ammonium nitrate fertilizer and predatory stress: differences between populations on a local scale

    OpenAIRE

    Ortíz-Santaliestra, Manuel E.; Fernández-Benéitez, María José; Lizana, Miguel; Marco, Adolfo

    2011-01-01

    — Agriculture-related pollution is among the major causes of global amphibian population declines. The multiple stressors to which amphibians are exposed in the field, such as predation pressure, can make agrochemicals far more deadly than when they act in isolation. Even within a small area, diffuse agricultural pollution does not affect all aquatic environments equally, which could account for local differences in amphibian sensitivity to agrochemicals. We examined the combined effects of am...

  16. Tribulations of a prostate cancer trial - lessons learned from TOAD, a cancer council Victoria and Transtasman Radiation Oncology Group Trial

    International Nuclear Information System (INIS)

    Full text: From 2004-2009 a total of 226 out of a target of 750 prostate cancer patients have been randomised into the Timing of Androgen Deprivation trial between immediate and delayed androgen deprivation. A screening log was kept by participating centres for the first 928 patients, which documented the reasons for non-entry into the trial; 42.7% of screened patients were ineligible and a further 33.0% were not entered for other reasons. Fewer than 10% of patients cited not wanting to be part of a clinical trial as a reason for non-entry. Strategies to improve recruitment included broadening the eligibility criteria, encouraging international collaboration, the use and support of research nurses in the private health care environment, and the use of phone follow-up. Recruitment will be completed at the number originally intended to inform the interim analysis designed to test the validity of the statistical assumptions, and a combined survival analysis with the Canadian study is planned.

  17. Distribution of Boreal Toad Populations in Relation to Estimated UV-B Dose in Glacier National Park, Montana, USA

    Science.gov (United States)

    This work provides information on amphibian distributions as well as the range of UV-B exposure in mountain habitats, and will be of use to scientists interested in tracking changes in amphibian distributions and abundance, and spatial and temporal patterns of UV-B exposure

  18. THE EFFECT OF SUBSTRATE TYPE ON AVOIDANCE OF UREA IN JUVENILE WESTERN TOADS (BUFO BOREAS). (U915529)

    Science.gov (United States)

    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...

  19. Widespread occurrence in frogs and toads of skin compounds interacting with the ouabain site of Na+, K+-ATPase.

    Science.gov (United States)

    Flier, J; Edwards, M W; Daly, J W; Myers, C W

    1980-05-01

    Amphibians of the family Bufonidae contain high levels of skin compounds that both inhibit Na+- and K+-dependent adenosinetriphosphatase and antagonize the binding of ouabain to the enzyme. In species of Bufo and Atelopus, these compounds are relatively nonpolar bufodienolides, whereas Dendrophryniscus and Melanophryniscus contain more polar compounds of unknown structure. Skin extracts from 30 of 48 species of frogs representing an additional eight families contained relatively low levels of compounds that inhibit binding of ouabain to Na+,K+-adenosinetriphosphatase. The widespread occurrence of low levels of inhibitory compounds is consonant with the role for these compounds as physiological regulators of Na+,K+-adenosinetriphosphatase in amphibian skin; high levels in the Bufonidae probably also serve as a defense against some predators. PMID:6245447

  20. Políticas públicas de inclusión en la educación superior los casos de Argentina y Brasil Public policies for inclusion in higher education the Argentinian and Brazilian cases

    Directory of Open Access Journals (Sweden)

    Adriana Chiroleu

    2009-08-01

    Full Text Available Las políticas inclusivas en la educación superior se orientan a lograr que las instituciones contengan una diversidad racial, cultural y sexual semejante a la que existe en el seno de la sociedad, en procura de remediar discriminaciones históricas que han conducido a la situación de desigualdad por la que atraviesan esos grupos. En este sentido, la implementación en algunos países de Políticas de Acción Afirmativa en el ámbito de la educación superior procura una mayor integración social en sociedades caracterizadas por fragmentaciones de diferente naturaleza. En este trabajo nos proponemos abordar desde una perspectiva comparativa los alcances de las políticas públicas de inclusión en la universidad que se desarrollan en Argentina y Brasil, enmarcándolas en los rasgos diferenciales de sus estructuras sociales y sus sistemas de Educación superior.Inclusive policies in higher education are planned to achieve racial, cultural and sexual diversity in institutions, similarly to social diversity itself. Such policies are intended to repair historical discrimination that has contributed to the unequal situation those groups have been facing. For such, the establishment of Affirmative Action Policies in the higher education field in some countries is intended to achieve greater social integration in societies that are usually characterized by fragmentation of different kinds. The purpose of this paper is to address, from a comparative perspective, the advances of public policies for university inclusion in Argentina and Brazil, considering the differences between their social structures and higher education systems.

  1. Fotografías de indígenas en manuales escolares argentinos: representaciones visuales y connotaciones textuales Photographs of indigenous people in argentinian school textbooks: visual representations and textual connotations

    Directory of Open Access Journals (Sweden)

    María José Saletta

    2012-07-01

    Full Text Available El objetivo de este trabajo es analizar las fotografías de pueblos originarios argentinos utilizadas en manuales escolares de 2o y 3o ciclo publicados por dos editoriales: Santillana y Aique. Se presentan los resultados de un análisis cuantitativo y cualitativo de 93 fotografías correspondientes a 38 manuales publicados entre los anos 2000 y 2005. Se reconoce qué tipo de imágenes son utilizadas, la presencia o no de cultura material autóctona, la utilización de epígrafes y la adscripción étnica de los retratados. Se concluye que existe una representación diferencial a favor de aquellas imágenes que muestran pueblos originarios con su cultura material, pero, al mismo tiempo, una utilización de un lenguaje que emplea términos como "aborigen", que implica un sesgo homogeneizador. Las fotografías son empleadas sólo en su función denotativa, mientras que se deja de lado la connotación visual en privilegio de la textual. La información presente en epígrafes y textos que acompanan a las imágenes no cumple con los requisitos necesarios de precisión y rigurosidad.The aim of this paper is to analyze photographs of native people in Argentinean primary and secondary school textbooks published by two companies, Santillana and Aique. Results from quantitative and qualitative analyses of 93 images taken from 38 school text books published between 2000 and 2005 are presented. Type of image used, presence of autochthonous material culture, use of epigraphs, and the ethnic adscription of the subjects portrayed are analyzed. It is concluded that there is differential representation in favor of those images showing native people with their material culture, although the use of language that contains derogative terms such as "aborigen" (i.e., native people at the same time clearly indicates an homogenizing bias. Images are used mostly denotatively, while textual connotation is privileged over visual connotation. Information on the epigraphs and texts accompanying an image do not fulfill the requirements of thoroughness and accuracy, thus reducing the images to illustrations rather than useful documents.

  2. LA "LEGITIMIDAD" DEL ENUNCIADOR JURÍDICO EN LA LEY DE RADIODIFUSIÓN ARGENTINA (22285/80 THE JURIDICAL SPEAKER’S LEGITIMACY IN THE ARGENTINIAN RADIO BROADCASTING LAW (22285/80

    Directory of Open Access Journals (Sweden)

    Adriana Callegaro

    2009-06-01

    Full Text Available Este artículo aborda el análisis discursivo de la exposición de motivos de la Ley 22285/80, que legisla acerca de la radiodifusión en Argentina. La misma, surgida en el contexto de la dictadura militar y firmada por Jorge R. Videla, Emilio E. Massera y Albano Harguindeguy, carece de la legitimidad proveniente del lugar de producción en la medida en que no emana de institución democrática alguna. Mediante la aplicación de instrumentos teóricos provenientes del Análisis del Discurso Argumentativo, se pretende dar cuenta de las estrategias discursivas que despliega el texto para constituirse en locutor legítimo, en la medida en que carece del ethos prediscursivo necesario. No obstante, el revelamiento de las formas lingüísticas y los procedimientos argumentativos permiten dar cuenta de la realidad implicada en dicha norma, más allá de los numerosos procedimientos que pretenden enmarcar la comunicación en una realidad democrática inexistente. La apelación a entimemas, que recurren al saber de la creencia y a la autoridad de la doxa, no logra encubrir los objetivos de control sobre las comunicaciones y asegura la perdurabilidad de esta ley, aún vigente luego de varias décadas de gobiernos constitucionales.This paper aproaches a discursive analysis of the preliminary recitals in the 22285/80 Law, which regulates radio broadcasts in Argentina. It was enacted within a context of military dictatorship and was signed by Jorge R. Videla, Emilio E. Massera and Albano Harguindeguy. It lacks the legitimacy that should come from the production site, since it wasn't promulgated by any democratic institution. By using theoretical tools from Argumentative Discourse Analysis, we intend to evidence the discursive strategies displayed in the text in order to become a legitimate speaker, given its lack of the necessary pre-discursive ethos. Nevertheless, the change of lingüistic forms and argumentative procedures sheds light on the reality involved in this Law, beyond the many techniques that attempt to frame communication in a nonexistent democratic reality. The use of enthymemes, which appeal to the belief's knowledge and the norm's authority, does not manage to hide the controlling purposes over communications and assures the endurance of this law, still in force after several decades of constitutional governments.

  3. Estimación bayesiana de componentes de (covarianza en Brangus argentino para caracteres de res mediante el algoritmo FCG Bayesian estimation of (co variance components in Argentinian Brangus for carcass traits using the FCG algorithm

    Directory of Open Access Journals (Sweden)

    R. J. C. Cantet

    2010-06-01

    Full Text Available Se emplearon los datos de 2273 toritos y vaquillonas Brangus para estimar las heredabilidades (h² y las correlaciones aditivas y ambientales de caracteres de calidad de carne medidos por ultrasonido. Los registros provenían del programa de evaluación genética de la Asociación Argentina de Brangus. Los caracteres medidos fueron el área del ojo del bife (AOB, el marmoreado (MB, la grasa dorsal (GD y la grasa de cadera (GC. La edad media de los animales al momento de la medición fue 641 días en machos y 685 días en hembras. Los parámetros genéticos y ambientales fueron estimados mediante un algoritmo bayesiano conjugado. Los valores estimados de h² fueron 0,22, 0,16, 0,12 y 0,21, para AOB, GD, CC y MB, respectivamente. En términos generales, las estimaciones de las correlaciones genéticas y ambientales se encontraron cercanas a la cifra media de la literatura. Si bien los valores estimados de h² fueron inferiores al promedio de la investigación realizada en vacunos para carne, la variabilidad encontrada es suficiente como para que la respuesta a la selección por estos caracteres - empleando predicciones de los valores de cría calculadas con los parámetros estimados - sea moderadamente efectiva.Data on 2273 Brangus young bulls and heifers were used to estimate heritabilities (h² and genetics and environmental correlations for ultrasound carcass measures. Records were from the genetic evaluation program of Asociación Argentina de Brangus. Traits measured were rib-eye area (AOB, marbling (MB, back-fat thickness (GD, and hip-fat thickness (GC. Average ages of measure were 641 days in males and 685 in females. The genetic and environmental dispersion parameters were estimated by a conjugate Bayesian algorithm (FCG. Estimates of h² were 0,22, 0,16, 0,12, and 0,21, for AOB, GD, CC, and MB, respectively. In general, estimates of genetic and environmental correlations were close to the average published values. Even tough estimates of h² were below the average of published estimates for beef cattle, the additive genetic variation found in the current study would lead to a moderate response to selection - using predictions of breeding value that are calculated with the estimate parameters.

  4. La privatización de la educación Argentina: un largo proceso de expansión y naturalización Privatization of Argentinian education: an enduring process of expansion and naturalization

    Directory of Open Access Journals (Sweden)

    Susana E. Vior

    2012-08-01

    Full Text Available En el artículo se revisan los momentos más importantes de la política educacional en Argentina en relación con el proceso de privatización de la vida social. Despejando algunas hipótesis habituales, se analiza ese proceso como resultado del modo en que se fueron resolviendo las demandas concretas de los grupos, fracciones o clases a lo largo de la historia nacional, culminando en la consolidación de un sólido sector de proveedores privados de educación, al amparo de medidas que le aseguran el financiamiento estatal y la presencia de sus intereses en la elaboración de la política educativa pública. Se interpreta el sentido del proceso en el marco del reacomodamiento de los intereses dominantes en esta etapa de recomposición capitalista, que realiza su hegemonía mediante la naturalización de las diversas formas de privatización de la educación nacional, tanto históricas como "novedosas", y oculta sus efectos concretos: la devaluación de la educación pública como bien universal y del papel del Estado como garante de su distribución igualitaria.In this paper the most important moments of the educational policy in Argentine, related to the privatization process of social life, are reviewed. Putting aside some commonplace hypothesis, this process is analyzed as a consequence of the ways involved in the response to demands from classes or groups along the history of our country. This process led to the strengthening of a group of private suppliers of educational services, protected by measures that guarantee the financial support from the State and the presence of their interests when public education policies are prepared. The meaning of this process is considered within the frame of resetting the predominant forces in the present period of capitalism. Its hegemony is settled making the different forms of privatization -traditional or new of the national education system look natural, and hiding their real effects: the devaluation of public education as a universal value and of the role of the State to guarantee that education is equally distributed.

  5. Estimación bayesiana de componentes de (co)varianza en Brangus argentino para caracteres de res mediante el algoritmo FCG Bayesian estimation of (co) variance components in Argentinian Brangus for carcass traits using the FCG algorithm

    OpenAIRE

    Cantet, R. J. C.; A. N. Birchmeier

    2010-01-01

    Se emplearon los datos de 2273 toritos y vaquillonas Brangus para estimar las heredabilidades (h²) y las correlaciones aditivas y ambientales de caracteres de calidad de carne medidos por ultrasonido. Los registros provenían del programa de evaluación genética de la Asociación Argentina de Brangus. Los caracteres medidos fueron el área del ojo del bife (AOB), el marmoreado (MB), la grasa dorsal (GD) y la grasa de cadera (GC). La edad media de los animales al momento de la medición fue 641 día...

  6. Role of Mitochondria-rich Cells for Passive Chloride Transport, discussion of Ussing's Contribution to Our Understanding of Shunt Pathways in Epithelia

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Kristensen, Poul; Nedergaard, Signe Nielsen;

    2001-01-01

    Toad skin, Mitochondria-rich cells, Chloride channels, Epithelial shunt pathways, Leaky epithelia, Recirculation theory of isotonic transport......Toad skin, Mitochondria-rich cells, Chloride channels, Epithelial shunt pathways, Leaky epithelia, Recirculation theory of isotonic transport...

  7. Mechanisms of ion transport in the mesonephric collecting duct system of Bufo bufo as revealed by microelectrode recordings in isolated perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2002-01-01

    amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad......amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad...

  8. Drug: D06750 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available cine in Japan [BR:br08304] Crude Drugs Drugs for external use Drugs for external use D06750 Toad venom Crude drugs [BR:br08305] Animals Amphibians D06750 Toad venom PubChem: 47208401 ...

  9. Risk from radionuclides: a frog's perspective : Accumulation of 137Cs in a riparian wetland, radiation doses, and effects on frogs and toads after low-dose rate exposure

    OpenAIRE

    Stark, Karolina

    2006-01-01

    Threats from man-made radionuclides include waste issues, increasing number of power plants, underground bomb testing, nuclear weapons, and “dirty bombs”. Until recently the ionizing radiation protection system focused on protecting humans with an implied protection of biota. However, goals of sustainable development and precautionary principles for human activity are leading to an inclusion of plant and animal populations in the protection system. From this perspective, the present thesis ex...

  10. A contribution to the knowledge of the trophic spectrum of the Common toad (Bufo bufo L., 1758 (Amphibia: Anura from Bulgaria

    Directory of Open Access Journals (Sweden)

    Petar Boyadzhiev

    2009-07-01

    Full Text Available During our study we identified 500 prey items in 20 prey categories in the trophic spectrum of Bufo bufo with average number of prey items per stomach 25.00. The most important prey taxon is Formicidae (70.20%, followed by Coleoptera (especially Carabidae – 11.40%, as well as non-insect invertebrates (Isopoda, Gastropoda, Arachnida which also play significant role. The estimated trophic niche breadth is low – 1.96.

  11. Scaling new heights: first record of Boulenger’s Lazy Toad Scutiger boulengeri (Amphibia: Anura: Megophryidae from high altitude lake in Sikkim Himalaya, India

    Directory of Open Access Journals (Sweden)

    Barkha Subba

    2015-08-01

    Full Text Available Frogs in the genus Scutiger of the family Megophryidae are the highest altitude frogs in the world, and are endemic to eastern Himalaya. Here, we report the occurrence of Scutiger boulengeri (Bedriaga, 1898 in one of the highest altitude lakes in the world, Lake Gurudongmar. This is the first report of Scutiger boulengeri from India and the first record of any amphibian species to be found at an altitude as high as 5270m, thus setting a world record for the highest altitude frog. Scutiger sikimmensis (Blyth, 1855 is another species of the genus Scutiger found in this region. This species is often confused with Scutiger boulengeri due to similar morphology and habitat overlap. We provide a detailed account of both S. boulengeri and S. sikimmensis based on morphology and molecular identification techniques. 

  12. On-line comprehensive two-dimensional normal-phase liquid chromatography×reversed-phase liquid chromatography for preparative isolation of toad venom.

    Science.gov (United States)

    Li, Jia-Fu; Fang, Hua; Yan, Xia; Chang, Fang-Rong; Wu, Zhen; Wu, Yun-Long; Qiu, Ying-Kun

    2016-07-22

    An on-line comprehensive preparative two-dimensional normal-phase liquid chromatography×reversed-phase liquid chromatography (2D NPLC×RPLC) system was constructed with a newly developed vacuum evaporation assisted adsorption (VEAA) interface, allowing fast removal of NPLC solvent in the vacuum condition and successfully solving the solvent incompatibility problem between NPLC and RPLC. The system achieved on-line solvent exchange within the two dimensions and its performance was illustrated by gram-scale isolation of crude extract from the venom of Bufo bufo gargarizans. Within separation time of ∼20h, 19 compounds were obtained with high purity in a single run. With the VEAA interface, the 2D system exhibited apparent advantages in separation efficiency and automation compared with conventional methods, indicating its promising application in the routine separation process for complicated natural products. PMID:27328884

  13. On The Identity Of Some Toads Of The Genus Bufo From Ecuador, With Additional Remarks On Andinophryne Colomai Hoogmoed, 1985 (Amphibia: Anura: Bufonidae).

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1989-01-01

    Study of the type specimens of B. caeruleostictus Günther, 1859 and B. chanchanensis Fowler, 1913, and of fresh material showed that B. chanchanensis is a junior subjective synonym of B. caeruleostictus. Probably it is a member of the B. guttatus group. B. caeruleocellatus Fowler, 1913 is a junior s

  14. Exploring the Genetic Basis of Adaptation to High Elevations in Reptiles: A Comparative Transcriptome Analysis of Two Toad-Headed Agamas (Genus Phrynocephalus)

    Science.gov (United States)

    Yang, Weizhao; Qi, Yin; Fu, Jinzhong

    2014-01-01

    High elevation adaptation offers an excellent study system to understand the genetic basis of adaptive evolution. We acquired transcriptome sequences of two closely related lizards, Phrynocephalus przewalskii from low elevations and P. vlangalii from high elevations. Within a phylogenetic framework, we compared their genomic data along with green anole, chicken and Chinese softshell turtle, and identified candidate genes and functional categories that are potentially linked to adaptation to high elevation environments. More than 100 million sequence reads were generated for each species via Illumina sequencing. A de novo assembly produced 70,919 and 62,118 transcripts for P. przewalskii and P. vlangalii, respectively. Based on a well-established reptile phylogeny, we detected 143 positively selected genes (PSGs) along the P. vlangalii lineage from the 7,012 putative orthologs using a branch-site model. Furthermore, ten GO categories and one KEGG pathway that are over-represented by PSGs were recognized. In addition, 58 GO categories were revealed to have elevated evolutionary rates along the P. vlangalii lineage relative to P. przewalskii. These functional analyses further filter out PSGs that are most likely involved in the adaptation process to high elevations. Among them, ADAM17, MD, and HSP90B1 likely contributed to response to hypoxia, and POLK likely contributed to DNA repair. Many other candidate genes involved in gene expression and metabolism were also identified. Genome-wide scan for candidate genes may serve as the first step to explore the genetic basis of high elevation adaptation. Detailed comparative study and functional verification are needed to solidify any conclusions. High elevation adaptation requires coordinated changes in multiple genes that involve various physiological and biochemical pathways; we hope that our genetic studies will provide useful directions for future physiological or molecular studies in reptiles as well as other poikilothermic species. PMID:25386640

  15. Historical biogeography resolves the origins of endemic Arabian toad lineages (Anura: Bufonidae): Evidence for ancient vicariance and dispersal events with the Horn of Africa and South Asia

    OpenAIRE

    Portik, Daniel M; Papenfuss, Theodore J.

    2015-01-01

    Background The Arabian Peninsula is home to a unique fauna that has assembled and evolved throughout the course of major geophysical events, including the separation of the Arabian Plate from Africa and subsequent collision with Eurasia. Opportunities for faunal exchanges with particular continents occurred in temporally distinct periods, and the presence of African, Western Eurasian, and South Asian derived taxa on the Arabian Peninsula signifies the complexity of these historical biogeograp...

  16. Geographic variation in Incilius occidentalis (Anura: Bufonidae), an endemic toad from Mexico, with a redescription of the species and delimitation of the type locality

    OpenAIRE

    Georgina Santos-Barrera

    2014-01-01

    A taxonomic revision of the populations referable to the wide ranging species Incilius occidentalis was conducted based on 10 morphometric variables and other external morphological traits. Thirty three populations were geographically defined from more than 220 locality records of the species. A brief summary of the nomenclatural history of this species is presented and the external morphological variation is analyzed. Incilius occidentalis is here redescribed on the basis of comparisons with...

  17. Membrane potentials and intracellular Cl- activity of toad skin epithelium in relation to activation and deactivation of the transepithelial Cl- conductance

    DEFF Research Database (Denmark)

    Willumsen, N J; Larsen, Erik Hviid

    1986-01-01

    , but was independent of whether the external bath was NaCl-Ringer's, NaCl-Ringer's with amiloride, KCl-Ringer's or choline Cl-Ringer's. To partition the routes of the conductive Cl- ion flow, we measured in the isolated epithelium with double-barrelled microelectrodes apical membrane potential. Va, and intracellular...

  18. Effect of Uncaria rhynchophyla Mig.jackas on the heart of toad%钩藤对蟾蜍心脏的作用机制研究

    Institute of Scientific and Technical Information of China (English)

    唐省三

    2002-01-01

    目的:探讨钩藤对蟾蜍心脏的作用.方法:用钩藤灌流蟾蜍心脏,观察灌流前后心肌收缩力、心输出量和心率的变化.结果心肌收缩幅度减小、心输出量减少和心率变慢.结论:钩藤对蟾蜍心脏有抑制作用,从而降低血压.

  19. Range extension of Ferguson Toad Duttaphrynus scaber (Schneider (Amphibia: Anura: Bufonidae up to the northern most limit of Western Ghats, with its advertisement call analysis

    Directory of Open Access Journals (Sweden)

    A. Padhye

    2013-07-01

    Full Text Available Duttaphrynus scaber (Schneider is known to occur in the southern Western Ghats, Eastern Ghats and northeastern India. However, there is no report of its occurrence from the northern Western Ghats from the states of Maharashtra and Gujarat. Here we report the occurrence of this species from the northernmost limit of the Western Ghats, a substantial range extension (approx. 550km from the nearest known locality. We confirm our identification on the basis of morphology by comparing our specimens with a previously collected Duttaphrynus scaber specimen from Thrissur in Kerala State as well as on the molecular basis. Analysis based on the advertisement call of Duttaphrynus scaber, albeit preliminary, is provided for the first time for this species.

  20. A new genus of Toads (Amphibia: Anura: Bufonidae) from the Pacific Slopes of the Andes in Northern Ecuador and Southern Colombia, with the description of two new species

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1985-01-01

    The genus Andinophryne, characterized by the presence of an omosternum, an externally visible tympanum, elongate parotoids and extensively webbed hands and feet is described from the Pacific versant of the Andes in northwestern Ecuador and southwestern Colombia. Two new species, Andinophryne colomai

  1. Lino Baranao, President of the National Agency for the Promotion of Science and Technology in Argentina, toured the ATLAS experiment's underground cavern during his visit to CERN on 9 May

    CERN Multimedia

    Patrice Loïez

    2005-01-01

    Picture 01 : Here he is seen with ATLAS spokesperson, Peter Jenni (left), and the ATLAS Muon System project leader, Giora Mikenberg, listening to Karina Loureiro (right), an Argentinian student at the University of Wisconsin

  2. Spent fuel management in Argentina

    International Nuclear Information System (INIS)

    The general program on Argentinian Spent Fuel Management has been presented in the previous meeting. This presentation includes an updating of the programs and a short description of the mixed oxide rods pilot plant. (author). 1 fig., 5 photographs

  3. Spent fuel management in Argentina

    International Nuclear Information System (INIS)

    The general program on Argentinian Spent Fuel Management has been informed in previous meetings and IAEA publications. This presentation includes an updating of the programs and a short description of the dry storage of Embalse NPP spent fuel. (author)

  4. The Need for Training in the Metal Recycling Industry

    International Nuclear Information System (INIS)

    This paper describes the experiences of an Argentinian steelmaking company in installing and operating equipment for detecting radioactive material in scrap metal. The lessons learned and the improvements made on the basis of the experience gained are documented. (author)

  5. ABACC ten years applying safeguards

    International Nuclear Information System (INIS)

    The Argentinian-Brazilian Agency for Accounting and Control of nuclear special materials has been in operations for ten years. The rational behind the creation and the work performed by the Agency during the last decade is described. (author)

  6. Gastronomie Argentiny

    OpenAIRE

    Cypriánová, Michaela

    2015-01-01

    The aim of this thesis is to characterize Argentinian gastronomy with emphasis on regional differences and also to ascertain a situation of representation of Argentinian gastronomy in Prague. The thesis is divided into six chapters where the first two chapters deal with the theoretical background, namely the importance of tourism and gastronomy and their mutual relationship and also a description of the locality of Argentina from the point of view of geographical, demographical, historical an...

  7. Advertisement call of species of the genus Frostius Cannatella 1986 (Anura: Bufonidae)

    OpenAIRE

    Flora A. Juncá; David L. Röhr; Ricardo Lourenço-de-Moraes; Flávio J.M. Santos; Airan S. Protázio; Ednei A. Mercês; Mirco Solé

    2012-01-01

    Frostius pernambucensis and F. erythrophthalmus are cryptic bufonid species recognized mainly by the iris color: yellow in F. permambucensis and red in F. erythrophthalmus. However, field studies showed that the iris color of F. erythrophthalmus could vary between yellow and red. To improve the recognition of these species we described the advertisement call of Frostius pernambucensis and Frostius erythrophthalmus and we tested if call characteristics are influenced by temperature, male size ...

  8. The structure of zetekitoxin AB, a saxitoxin analog from the Panamanian golden frog Atelopus zeteki: A potent sodium-channel blocker

    OpenAIRE

    Yotsu-Yamashita, Mari; Yong H Kim; Dudley, Samuel C.; Choudhary, Gaurav; Pfahnl, Arnold; Oshima, Yasukatsu; Daly, John W.

    2004-01-01

    Bufonid anurans of the genus Atelopus contain both steroidal bufadienolides and various guanidinium alkaloids of the tetrodotoxin class. The former inhibit sodium-potassium ATPases, whereas the latter block voltage-dependent sodium channels. The structure of one guanidinium alkaloid, zetekitoxin AB, has remained a mystery for over 30 years. The structure of this alkaloid now has been investigated with a sample of ≈0.3 mg, purified from extracts obtained decades ago from the Panamanian golden ...

  9. Les « clubs de troc » argentins : un microcosme monétaire Credito dépendant du macrocosme Peso The Argentinian Barter clubs: a monetary microcosm Credito dependent of the monetary macrocosm Peso Los clubes de trueque argentinos: un microcosmos monetario. Crédito dependiente del macrocosmos Peso

    Directory of Open Access Journals (Sweden)

    Pepita Ould-Ahmed

    2010-06-01

    Full Text Available Cet article s’intéresse à un cas concret de système monétaire local, celui des « clubs de troc » développés en Argentine à partir de 1995. Contrairement à ce que leur nom laisse penser, les « clubs de troc » désignent des espaces marchands communautaires, à l’intérieur desquels les transactions économiques sont réglées en credito, monnaie-papier interne et non convertible avec la monnaie officielle. La question que pose ce type d’expérience monétaire parallèle est de savoir pourquoi et sous quelles conditions cette monnaie privée non convertible avec la monnaie officielle parvient à être acceptée. Est-ce que ce micro-système monétaire peut fonctionner de manière indépendante et cloisonnée, ou bien a-t-il besoin de nouer des rapports avec le macro-système monétaire officiel ? Telles sont les questions auxquelles cet article se propose de répondre.This paper examines a concrete case of local currency systems, the Argentine “barter clubs” developed from 1995. “Barter club” denotes a place of market exchange, within which economic transactions are paid for using an internal paper currency, the “credito”, issued by the founders of these clubs and not convertible with the official currency. Its starting point is to wonder why and under what conditions this private currency, non-convertible with the official currency, is accepted. Could this micro-monetary system operate in an insular and independent manner, or was it necessary to establish some kind of relation with the official macro-monetary system? These are the questions that this article sets out to answer.Este artículo se interesa sobre un caso concreto del sistema monetario local, el de los “clubes de trueque”, desarrollados en Argentina a partir de 1995. Contrariamente a lo que su nombre deja pensar, los “clubes de trueque” designan los espacios comerciales comunitarios, al interior de los cuales las transacciones económicas son reguladas mediane créditos, moneda papel interna y no convertible con la moneda official, que llegan a ser aceptados. En ese micro sistema monetario ¿puede funcionar de manera independiente y encapsulada, o tienen necesidad de establecer relaciones con el macro sistema monetario official? Tales son las cuestiones a las cuales este artículo se propone responder.

  10. Infancia, dibujos animados y televisión pública. La difusión de valores y contravalores en la producción española y argentina Childhood, cartoons and public television. The diffusion of the values and disvalues in the Spanish and Argentinian production

    Directory of Open Access Journals (Sweden)

    Gabriela Fabbro

    2016-01-01

    Full Text Available La exposición a los medios 'cultiva' la forma de comprender el mundo asentando creencias, representaciones mentales y actitudes que llegan a modificar la concepción de la realidad. Ante esta situación, la audiencia infantil es la que más interesa ya que consume productos audiovisuales en un momento de formación en la que preocupa qué ven en televisión y cómo lo interpretan. Por ello, y por ser un público vulnerable que aprende y aprehende lo que les viene impuesto, el objetivo de este trabajo es comprobar el compromiso de la televisión pública en España y Argentina por producir contenidos adecuados para los niños y niñas. Mediante una metodología cualitativa, y usando como herramienta de abordaje el análisis de contenido, se ha podido demostrar que ambos países difunden programas infantiles basados en valores. Aunque este trabajo tiene las limitaciones propias de un diseño experimental basado en un número de observaciones limitadas, los resultados son relevantes para demostrar que desde la perspectiva del discurso televisivo como informador y formador, la televisión pública de ambos países contribuye al enriquecimiento cognitivo de los niños y niñas que los consume, potenciando así la educación en valores. The media exposure ‘cultivate’ the way to understand the world by setting beliefs, mental representations and attitudes that change the conception of reality. In this situation, childish audience is the most interesting one because it consumes audiovisual products in a formative stage in which it worries what they watch on TV and how they interpret it. By then, being a vulnerable audience that learn and apprehend what is imposed to them, the aim of this study is to confirm the agreement of the public television in Spain and Argentina to produce suited contents for children. By a qualitative methodology, and by using the analysis of content as a tool, it has been shown that both countries broadcast children programmes based on values. Although this study has its own limitations of experimental design based on a limited number of observations, the results are important for demonstrating that from the perspective of the television speech as reporter and former, public television of both countries contribute to children’s cognitive knowledge that consume it, strengthening to education on values.

  11. La política social y la recomposición material del consenso: la centralidad de los programas de Transferencia de Renta Condicionada: el caso argentino Social policy and the material reform of the agreement: the central character of the programs of Conditioned Income Transfer: the Argentinian case

    Directory of Open Access Journals (Sweden)

    Silvia Fernández Soto

    2013-03-01

    Full Text Available En el marco de una estrategia global de recomposición material del consenso, analizamos el programa de Transferencia de Renta Condicionada, Asignación Universal por hijo para protección social (AUH en Argentina. Desde una perspectiva amplia y compleja de análisis de la política social, identificamos problemas en relación a la orientación y sentido ético político que persigue, en un contexto de disputa de las perspectivas de protección social. Analizamos algunas tensiones centrales: la relación de las condiciones y formas de organización del trabajo y las desigualdades contemporáneas con las formas de protección social; el papel de las condicionalidades y las tensiones con perspectivas universalistas.In the context of an overall strategy of material reform of the agreement, we have analyzed the program of Conditioned Income Transfer, Universal Allocation per Child for social protection (AUH - Asignación Universal per hijo in Argentina. From a broad and complex analysis of the social policy, we have identified problems related to the orientation and political ethical sense in a disputing context of the perspectives of social protection. We have analyzed some central tensions: the relationship between the conditions and forms of work organization and inequalities and the contemporary forms of social protection; the role of conditions and tensions and the universal perspective.

  12. GARGANTA SECA Y ARENA EN LAS BOTAS: PROSPECTANDO ANTECEDENTES ARQUEOLÓGICOS DE LAS TIERRAS ÁRIDAS DEL NORESTE MENDOCINO (CENTRO OESTE ARGENTINO (Dry throat and sand in the boots: Prospecting archaeological backgrounds of the Mendoza Northeastern drylands, Argentinian Center South

    Directory of Open Access Journals (Sweden)

    Horacio Chiavazza

    2009-03-01

    Full Text Available Aquí se presenta un detallado estado de las investigaciones arqueológicas desarrolladas en el noreste de la provincia argentina de Mendoza. Esta zona es objeto de estudios desde principios del siglo XX. Sin embargo los pulsos de la investigación han registrado etapas de abandono total y de intervenciones selectivas. Los investigadores han partido de los trabajos precedentes para explicar por extensión las modalidades de asentamiento en la totalidad del territorio norte y, sobre todo, del occidente montañoso, que era donde concentraban sus campañas. Esto acabó generando un cuadro de antecedentes desequilibrado y superficial en el conocimiento de dicha área, con implicaciones en el cuadro interpretativo general de la prehistoria local. En este caso, indagamos las posibles causas que dieron lugar a tal proceso, sus vínculos con los enfoques teóricos y metodologías dominantes a lo largo del siglo XX y su relación con la selección de zonas para llevar a cabo estudios de campo en el norte de la provincia. Reflexionamos críticamente sobre los alcances, límites y posibilidades que ofrece la región para profundizar los análisis arqueológicos del poblamiento prehispánico en relación con las condiciones del ambiente y los procesos históricos documentados, proponiendo discutir los enfoques que basan sus explicaciones en hechos dados por sentados y que merecerían antes una discusión en base a la evidencia disponible. ENGLISH: Here is a detailed state of archaeological research developed in the northeastern Argentine province of Mendoza. This area is the subject of studies since the early twentieth century. However, the pulses of the investigation have been stages of total abandonment and selective interventions. This ended up creating an unbalanced picture of history and superficial knowledge of that area, with implications for the general picture of prehistory interpreted locally. In this case, we investigate the possible causes leading to this process, their ties with the dominant theoretical approaches and methodologies throughout the twentieth century and their relationship with the selection of areas to conduct field studies in northern province. We reflect critically on the scope, limits and possibilities of the region for further archaeological analysis of prehistoric settlement to discuss approaches that base their explanations on facts taken for granted and which deserve before a discussion based on the evidence available.

  13. Chloroform fumigation-extraction labile C pool (microbial biomass C "plus" shows high correlation to microbial biomass C in Argentinian and Brazilian soils Alta correlación entre el "pool" de carbono lábil por fumigación con cloroformo-extracción (carbono de biomasa microbiana plus y carbono de biomasa microbiana en suelos de Argentina y Brasil

    Directory of Open Access Journals (Sweden)

    Helvécio De-Polli

    2007-07-01

    Full Text Available Chloroform fumigation-incubation and chloroform fumigation-extraction approaches have significantly contributed to assess soil microbial biomass. Some controversy is found in the literature about the suggestion to calculate microbial biomass carbon (MBC without the subtraction of the un-fumigated control, in opposition to the originally proposed method that requires such subtraction. Some authors consider the non-subtraction proceeding as a more robust method. Nevertheless, values obtained without subtraction of a control include other labile organic fractions of soil carbon besides microbial biomass. Therefore, due to the usefulness of this measurement we consider more appropriate to call it as chloroform-fumigation labile C pool or microbial biomass carbon "plus" (MBC PLUS. We used a vast series of data from soils of Argentina and Brazil under different management situations to verify whether MBC correlates to MBC PLUS. There was a significant statistical correlation between values of MBC obtained by fumigation-extraction method and the corresponding MBC PLUS. The MBC PLUS performed as well as MBC as an indicator to differentiate soil managements and their impact on soil quality.Los métodos de fumigación-incubación y fumigación extracción han contribuido significativamente a las determinaciones de biomasa microbiana del suelo. En la literatura se encuentran algunas controversias acerca de la sugerencia de calcular el carbono de biomasa microbiana (CBM sin la sustracción del control no fumigado, en oposición a las metodologías tradicionales que requieren de dicha sustracción. Algunos autores mencionan que el hecho de no realizar la sustracción hace al procedimiento más robusto. Sin embargo, los valores obtenidos sin la sustracción del control incluyen otras fracciones lábiles del carbono, además de la biomasa microbiana. Debido a lo útil que resulta esta medida consideramos adecuado llamarla "pool" de carbono lábil por fumigación con cloroformo o carbono de biomasa microbiana "plus" (CBM PLUS. Usamos una amplia serie de datos de suelos de Argentina y Brasil bajo diferentes situaciones de manejo para verificar si el CBM correlaciona con el CBM PLUS. Hubo una correlación estadísticamente significativa entre los valores de CBM obtenidos por el método de fumigación-extracción y los correspondientes a CBM PLUS. Este se vislumbra, al igual que el CBM, como un indicador para diferenciar situaciones de manejo de suelos y el impacto sobre su calidad.

  14. La Dimensión Global y Sexual de la Ciudadanía en América Latina y los Derechos Humanos- El Caso Argentino (The Global and Sexual Aspects of Citizenship and Human Rights in Latin America: The Argentinian Case

    Directory of Open Access Journals (Sweden)

    Maria Luisa Bartolomei

    2015-06-01

    Full Text Available The paper discusses the issue of sexual violence against women during the past military dictatorships in Latin America, especially in Argentina, and some consequences in the current practice of their sexual and reproductive rights. It analyzes the extent the exercise of sexuality has a connection with the exercise of power, which organizes, manages, and prioritizes behavior depending on a political, social and cultural project, in a context of time and space. This means that the public and private, power and sexuality depend on the idea of the nation, class, race and religion, and consequently implies the political control of reproduction and the family model, including expressions of gender sexual violence. The paper discusses feminist theoretical concepts, such as the concept of gender and nation from an intersectional perspective (Yuval Davis, the idea of post colonialism and decolonization of feminism (Mohanty, and the relationship between gender and globalization (Fraser. Este artículo debate el tema de la violencia sexual contra las mujeres durante las últimas dictaduras militares en América Latina, especialmente el caso argentino y sus efectos en el ejercicio actual de los derechos sexuales. En él se analiza cómo el ejercicio de la sexualidad tiene una relación con el poder, el cual organiza, gestiona, y jerarquiza conductas según un proyecto político, social y cultural, en un contexto determinado. Lo público y lo privado, el poder y la sexualidad en relación a los conceptos de patria, clase, raza y religión, y con ello el control político de la reproducción y del modelo de familia, y de la violencia sexual. En el análisis se discuten concepciones teóricas feministas, como el concepto de género y nación desde la perspectiva interseccional de Yuval Davis, la idea de postcolonialidad y descolonización del feminismo de Mohanty, y la relación entre género y globalización de Fraser. DOWNLOAD THIS PAPER FROM SSRN: http://ssrn.com/abstract=2611061

  15. TAFONOMÍA DE RESTOS ÓSEOS PROVENIENTES DE EGAGRÓPILAS DE CORAGYPS ATRATUS (JOTE DE CABEZA NEGRA) EN EL NOROESTE DE LA PATAGONIA ARGENTINA/Taphonomy of bones remains from pellets of Coragyps Atratus (black vulture) in the northwest of the argentinian Patag

    OpenAIRE

    Fernando Ballejo; Fernando Fernández; Luciano J. M. De Santis

    2012-01-01

    Existen diversos estudios actualísticos en tafonomía sobre restos de presas de diferentes especies de aves raptoras. Sin embargo, este tipo de trabajos en aves carroñeras ha sido escasamente considerado hasta el momento en Argentina, a pesar que ellas cumplen un papel fundamental en la alteración y transporte de cadáveres. Coragyps atratus (jote de cabeza negra) tiene la particularidad de formar posaderos comunales cercanos a áreas de actividades humanas y de alimentarse de animales de todos ...

  16. TAFONOMÍA DE RESTOS ÓSEOS PROVENIENTES DE EGAGRÓPILAS DE CORAGYPS ATRATUS (JOTE DE CABEZA NEGRA EN EL NOROESTE DE LA PATAGONIA ARGENTINA/Taphonomy of bones remains from pellets of Coragyps Atratus (black vulture in the northwest of the argentinian Patag

    Directory of Open Access Journals (Sweden)

    Fernando Ballejo

    2012-11-01

    Full Text Available Existen diversos estudios actualísticos en tafonomía sobre restos de presas de diferentes especies de aves raptoras. Sin embargo, este tipo de trabajos en aves carroñeras ha sido escasamente considerado hasta el momento en Argentina, a pesar que ellas cumplen un papel fundamental en la alteración y transporte de cadáveres. Coragyps atratus (jote de cabeza negra tiene la particularidad de formar posaderos comunales cercanos a áreas de actividades humanas y de alimentarse de animales de todos los tamaños, por lo que pueden interferir en la formación de sitios arqueológicos. El objetivo de este trabajo es realizar un análisis tafonómico sobre los restos óseos recuperados de egagrópilas de C. atratus en el Noroeste patagónico, con el fin de generar herramientas que permitan identificar a estas aves como posibles agentes acumuladores. Se recolectaron 469 egagrópilas distribuidas en tres posaderos del Noroeste patagónico. Se identificaron los elementos recuperados y se evaluaron los grados de alteraciones por ácidos gástricos. Lepus europaeus y Ovis aries dominaron las muestras. Los elementos más representativos pertenecen al autopodio, principalmente falanges. Todos ellos muestran signos de digestión, que van desde porosidades superficiales, perforaciones y fracturas, con la desaparición de la médula en el caso de varias falanges; denotando diferencias en relación al tamaño de la presa consumida. Abstract There are several actualistic taphonomic studies regarding different species of birds of prey. However, the studies focus on scavenger birds have been scarcely considered in Argentina, despite the fact that they play a fundamental role in the alteration and transportation of carcasses. A peculiar characteristic of Coragyps atratus (black vulture is that it builds communal roosts near places where human activities are developed and it feeds on animals of varying size, which may interfere with the formation of archaeological sites. The aim of this study is to perform a taphonomic analysis of the bones remains retrieved from pellets of C. atratus in the Northwest of Patagonia, with the purpose of creating tools that allow the identification of these birds as possible accumulator agents. 469 pellets, distributed in the three roosts of the patagonic norhtwest, were gathered. The elements retrieved were identified and the degrees of alterations caused by gastric acids were evaluated. Lepus europaeus and Ovis aries predominate in the samples. The main elements belong to the articular bones, mainly phalanges. They all show signs of digestion, from surface porosities to perforations and fractures, and in the case of several phalanges, the disappearance of marrow, denoting differences regarding the size of the ingested prey.

  17. El rol de la dirigencia política argentina en la promoción de un nuevo patrón de relaciones internacionales en la década de los noventa | The role of the political argentinian ruling class in the promotion of a new international relations pattern

    Directory of Open Access Journals (Sweden)

    María Cecilia MÍGUEZ

    2010-10-01

    Full Text Available En este artículo se analiza el rol de la dirigencia política argentina en la adopción de las reformas neoliberales en los inicios de la década de los noventa. En especial,  estudia una etapa de transición (1987-1991 hacia un consenso entre los dos partidos mayoritarios del sistema político respecto de la adopción de las reformas neoliberales, que profundizaron una inserción internacional dependiente. Se analizarán las posiciones de la Unión Cívica Radical y del Partido Justicialista respecto de tres dimensiones de la política exterior y de la política económica doméstica en dicho período, y las condiciones de gestación de dicho consenso.This article analyzes the role of Argentina’s political leadership in the adoption of neoliberal reforms in the early nineties. In particular, studies the formation of a consensus between the two major parties of the political system on foreign policy, in its various dimensions, which made possible the deepening of international integration dependent. It will analyze the structural and economic conditions of that consensus gestation and their specific content.

  18. Estudio transversal clínico y epidemiológico de la enfermedad de Chagas en una área rural del Nordeste Argentino Clinical and epidemiological transversal study on Chagas' disease in a rural area of the Argentinian Northeastern

    Directory of Open Access Journals (Sweden)

    María Esther Bar

    1998-04-01

    Full Text Available Esta investigación tiene por objeto analizar las características epidemiológicas, clínicas, electrocardiográficas y radiológicas de una población de seropositivos y seronegativos al Trypanosoma cruzi en una área rural del Departamento San Miguel, provincia de Corrientes, Argentina. Se seleccionaron 132 pobladores (58 hombres y 74 mujeres de todos los grupos etareos para la realización de un examen clínico y cardiovascular. Se registraron síntomas y signos compatibles con afección cardíaca, tensión arterial, electrocardiograma de 12 derivaciones y radiografía anteroposterior de tórax. En la signo-sintomatología, anomalías electrocardiográficas y en las alteraciones radiográficas detectadas, no se observaron diferencias estadísticamente significativas entre seropositivos y seronegativos. Se concluye que si bien en la población objeto de estudio la infección chagásica no se asoció a mayor prevalencia de cardiopatía, cabe destacar que los pacientes chagásicos pertenecían a un grupo etareo muy joven con un 54,0% de ellos menores de 20 años y que el 45,0% de los pacientes mayores de 41 años tenían alteraciones electrocardiográficas.The main goal was to know the epidemiologic, clinical, electrocardiographic and radiologic characteristics among a population of seropositives and seronegatives to Trypanosoma cruzi in a rural area of the Departament of San Miguel, province of Corrientes, Argentina. One hundred and thirty-two patients of different ages: 2-79 years old were researched (58 males, 74 females. In order to make a thorough assessment clinical evaluation and cardiologic testing were carried out. Signs and symptoms consistent with heart disease, blood pressure, 12-lead ECG registry and chest x-ray (PA view were registered. In signs and symptoms, abnormal ECG patterns and radiologic abnormalities, non-significant statistic difference were observed. Although we were unable to find a significant relationship between chagasic infection and a higher prevalence for heart disease, it is important to stress the fact that 54.0% of the studied population was largely composed of very young patients whose ages were less than 20 years old, and 45.0% of those older than 41 years showed ECG abnormalities.

  19. Rickettsia bellii in Amblyomma rotundatum ticks parasitizing Rhinella jimi from northeastern Brazil.

    Science.gov (United States)

    Horta, Mauricio C; Saraiva, Danilo G; Oliveira, Glauber M B; Martins, Thiago F; Labruna, Marcelo B

    2015-01-01

    This study evaluated rickettsial infection in Amblyomma rotundatum ticks collected from toads (Rhinella jimi) in the Brazilian Caatinga biome, an unique semiarid region of South America. Tick infestations were observed in 57.8% toads (26/45); mean infestation: 1.6 ticks/toad. DNA extraction from 42 ticks (6 larvae, 22 nymphs and 11 female adults) was tested by polymerase chain reaction (PCR) targeting Rickettsia organisms, which were detected in 100% of the ticks. Amplicons' DNA sequences were identical to each other and 99% identical to Rickettsia bellii from GenBank. DNA samples extracted from the blood of the 45 toads were negative by rickettsia-PCR protocols.

  20. Tissue kinetics, ion transport, and recruitment of mitochondria-rich cells in the skin of the toad (Bufo bufo) in response to exposure to distilled water

    DEFF Research Database (Denmark)

    Budtz, Poul Egede; Christoffersen, Betina C.; Johansen, Jesper S.;

    1995-01-01

    Mitochondria-rich cells (MRC) of the amphibian epidermis are responsible for active chloride uptake at low external salinity, and new MRCs are recruited in response to exposure to distilled (deionized) water. The time-course of this recruitment, the tissue kinetics and ion transport have been...

  1. 黄芪对蟾蜍离体单一肌梭传入放电的影响%Effect of Radix Astragali on the discharge of isolated toad muscle spindle

    Institute of Scientific and Technical Information of China (English)

    唐斌; 樊小力; 吴苏娣

    2003-01-01

    目的探讨黄芪、丹参对肌梭传入放电的影响.方法用空气隔绝法记录蟾蜍离体单一肌梭的传入放电,观察黄芪和丹参注射液对肌梭传入电活动的影响,并与琥珀胆碱(SCh)的作用进行比较.结果应用50 mg*L-1 SCh后,肌梭的自发放电频率由(0.79±0.12) Hz增加至(12.26±2.38) Hz.应用100、200、300 mg*L-1黄芪后,肌梭的传入放电分别由(0.80±0.34) Hz、(0.77±0.29) Hz、(0.70±0.42) Hz增加至(13.18±2.43) Hz、(24.03±4.07) Hz、(36.17±5.83) Hz.丹参注射液对肌梭的传入放电没有作用.结论黄芪可以使肌梭的传入放电频率显著增加,且呈剂量依赖现象.

  2. Effect of Cordycepin on Discharge of Isolated Toad Muscle Spindle%冬虫夏草增强蟾蜍离体单一肌梭传入放电频率

    Institute of Scientific and Technical Information of China (English)

    石磊; 廉西娟; 王保成; 樊小力; 吴苏娣

    2006-01-01

    目的:探讨冬虫夏草对肌梭传入放电的影响.方法:用蟾蜍缝匠肌制备单一肌梭标本以空气隔绝法记录单一肌梭的传入放电,观察冬虫夏草水提液对肌梭传入放电的影响.结果:应用50 mg/L、100 mg/L、200 mg/L冬虫夏草水提液后,肌梭的传入放电分别由(0.85±0.12)Hz、(0.87±0.12)Hz、(0.84±0.10)Hz增加至(10.52土2.48)Hz、(20.79±3.03)Hz、(29.25±4.08)Hz.结论:冬虫夏草水提液可以使肌梭的传入放电频率明显增加,且呈剂量依赖关系.

  3. Range extension of Ferguson Toad Duttaphrynus scaber (Schneider) (Amphibia: Anura: Bufonidae) up to the northern most limit of Western Ghats, with its advertisement call analysis

    OpenAIRE

    A. Padhye; Pandit, R.; Patil, R; S Gaikwad; N. Dahanukar; Y. Shouche

    2013-01-01

    Duttaphrynus scaber (Schneider) is known to occur in the southern Western Ghats, Eastern Ghats and northeastern India. However, there is no report of its occurrence from the northern Western Ghats from the states of Maharashtra and Gujarat. Here we report the occurrence of this species from the northernmost limit of the Western Ghats, a substantial range extension (approx. 550km) from the nearest known locality. We confirm our identification on the basis of morphology by comparing our spec...

  4. A toad getting a swan's flesh: review on the film If You Are The One (feicheng wurao)%癞蛤蟆吃到了天鹅肉——评《非诚勿扰》

    Institute of Scientific and Technical Information of China (English)

    胡建波

    2009-01-01

    实际上是讲了一只癞蛤蟆如何吃了天鹅肉的故事.从谁是大家心目中的天鹅、癞蛤蟆差点没吃着天鹅肉、几处拿捏得恰到好处的精彩故事、绚丽风景与爱情故事的完美融合,字字珠玑的台词等方面评论了冯导的这部经典之作.

  5. 78 FR 15737 - Incidental Take Permit Amendment and Supplemental Environmental Assessment for Wind Energy...

    Science.gov (United States)

    2013-03-12

    .... The Service previously advertised (71 FR 951), and issued in September 2006, TE104073 as a 40-year ITP... address the impacts to the Puerto Rican crested toad within the Punta Ventana section of the covered area... turbines in Guayanilla, Puerto Rico. Puerto Rican crested toads have been observed in the Punta...

  6. Cattle grazing and conservation of a meadow-dependent amphibian species in the Sierra Nevada.

    Directory of Open Access Journals (Sweden)

    Leslie M Roche

    Full Text Available World-wide population declines have sharpened concern for amphibian conservation on working landscapes. Across the Sierra Nevada's national forest lands, where almost half of native amphibian species are considered at risk, permitted livestock grazing is a notably controversial agricultural activity. Cattle (Bos taurus grazing is thought to degrade the quality, and thus reduce occupancy, of meadow breeding habitat for amphibian species of concern such as the endemic Yosemite toad (Anaxyrus [ = Bufo] canorus. However, there is currently little quantitative information correlating cattle grazing intensity, meadow breeding habitat quality, and toad use of meadow habitat. We surveyed biotic and abiotic factors influencing cattle utilization and toad occupancy across 24 Sierra Nevada meadows to establish these correlations and inform conservation planning efforts. We utilized both traditional regression models and Bayesian structural equation modeling to investigate potential drivers of meadow habitat use by cattle and Yosemite toads. Cattle use was negatively related to meadow wetness, while toad occupancy was positively related. In mid and late season (mid July-mid September grazing periods, cattle selected for higher forage quality diets associated with vegetation in relatively drier meadows, whereas toads were more prevalent in wetter meadows. Because cattle and toads largely occupied divergent zones along the moisture gradient, the potential for indirect or direct negative effects is likely minimized via a partitioning of the meadow habitat. During the early season, when habitat use overlap was highest, overall low grazing levels resulted in no detectable impacts on toad occupancy. Bayesian structural equation analyses supported the hypothesis that meadow hydrology influenced toad meadow occupancy, while cattle grazing intensity did not. These findings suggest cattle production and amphibian conservation can be compatible goals within this

  7. The Role of Domain-Specific Practice, Handedness, and Starting Age in Chess

    Science.gov (United States)

    Gobet, Fernand; Campitelli, Guillermo

    2007-01-01

    The respective roles of the environment and innate talent have been a recurrent question for research into expertise. The authors investigated markers of talent, environment, and critical period for the acquisition of expert performance in chess. Argentinian chess players (N = 104), ranging from weak amateurs to grandmasters, completed a…

  8. Draft Genome Sequences of Burkholderia contaminans, a Burkholderia cepacia Complex Species That Is Increasingly Recovered from Cystic Fibrosis Patients

    OpenAIRE

    Bloodworth, Ruhi A M; Selin, Carrie; López De Volder, Maria Agustina; Drevinek, Pavel; Galanternik, Laura; Degrossi, José; Cardona, Silvia T.

    2015-01-01

    Burkholderia contaminans belongs to the Burkholderia cepacia complex (BCC), a group of bacteria that are ubiquitous in the environment and capable of infecting the immunocompromised and people with cystic fibrosis. We report here draft genome sequences for the B. contaminans type strain LMG 23361 and an Argentinian cystic fibrosis sputum isolate.

  9. In-service inspection of steam generator pipes

    International Nuclear Information System (INIS)

    Tasks achieved during in-service inspection by Eddy currents in steam generator pipes of Atucha Reactor are described. Argentinian technicians made an ''on-the-job training'' under the supervision of KWU's personnel. This inspection was realized between November and December 1987

  10. Subduction controls on Miocene back-arc lavas from Sierra de Huantraico and La Matancilla, Argentina and new 40Ar/39Ar dating from the Mendoza Region, Argentina

    DEFF Research Database (Denmark)

    Dyhr, Charlotte Thorup; Holm, Paul Martin; Llambias, Eduardo J.;

    2013-01-01

    Back-arc volcanism in the western Argentinian provinces of Mendoza and Neuquén has been widespread from the Miocene to historic times. We present a detailed investigation of profiles through two of the major Miocene volcanic areas of the region, the neighboring Huantraico and LaMatancilla plateau...

  11. Specifika podnikatelského prostředí Argentinské republiky

    OpenAIRE

    Nováková, Karolína

    2010-01-01

    Presented work analyzes the business environment of the Republic of Argentina. It focuses on the economic, political and legislative, cultural and social, and institutional environment. It evaluates the mutual commercial relations between the Czech and Argentinian Republic and suggests possible business opportunities for their commercial exchange.

  12. An Introduction to American Literature.

    Science.gov (United States)

    Borges, Jorge Luis

    Offered in this book is an Argentinian's view of the literary achievement of the United States. The beginning chapters discuss Mather, Edwards, and Freneau; Franklin, Cooper, and the historians; Hawthorne and Poe; and Whitman and Herman Melville. Other chapters are given to a discussion of three poets of the nineteenth century (Lanier, Whittier,…

  13. Estrategias reproductivas de moluscos bivalvos y equinoideos

    OpenAIRE

    Calvo, J.; Morriconi, E.; Orler, P.

    1998-01-01

    The theoretical aspects of reproductive strategies and life histories are analyzed. The gonadal structures and the main features of gametogenesis of bivalves and echinoids are described. Research on the reproductive characteristics and gametogenic cycles of the bivalve molluscs in the Argentinian littoral and the echinoid Loxechinus albus is reviewed. Special references to Mytilus edulis, Aulacomya ater, Brachidontes purpuratus, Aequipecten tehuelchus, Zygochlamys patagonica, Ostrea puelchana...

  14. Little Sun

    DEFF Research Database (Denmark)

    Ebbesen, Toke Riis

    2017-01-01

    the ideas of Alfred Gell’s anthropology of art and the indicative framework derived from Argentinian semiotician Juan Pablo Bonta and Jørn Guldberg. The toy-like solar lamp Little Sun by Olafur Eliasson and Frederik Ottesen is used as case that blends the registers of social design and art...

  15. Detection of the emerging amphibian pathogens Batrachochytrium dendrobatidis and ranavirus in Russia

    Science.gov (United States)

    Reshetnikov, Andrey N.; Chestnut, Tara E.; Brunner, Jesse L.; Charles, Kaylene M.; Nebergall, Emily E.; Olson, Deanna H.

    2014-01-01

    In a population of the European common toad Bufo bufo from a rural pond in the region of Lake Glubokoe Regional Reserve in Moscow province, Russia, unexplained mass mortality events involving larvae and metamorphs have been observed over a monitoring period of >20 yr. We tested toads from this and a nearby site for the emerging amphibian pathogens Batrachochytrium dendrobatidis (Bd) and ranavirus (Rv). Both pathogens were detected, and at the rural pond site, with the above-noted losses and decline in toad breeding success, 40% of B. bufo metamorphs were Bd positive, 46% were Rv positive and 20% were co-infected with both pathogens. Toad metamorphs from a neighbouring water body were also Bd and Rv positive (25 and 55%, respectively). This is the first confirmation of these pathogens in Russia. Questions remain as to the origins of these pathogens in Russia and their roles in documented mass mortality events.

  16. Dynamic characterization of silicon nanowires using a terahertz optical asymmetric demultiplexer-based pump-probe scheme

    DEFF Research Database (Denmark)

    Ji, Hua; Cleary, C. S.; Dailey, J. M.;

    2012-01-01

    Dynamic phase and amplitude all-optical responses of silicon nanowires are characterized using a terahertz optical asymmetric demultiplexer (TOAD) based pump-probe scheme. Ultra-fast recovery is observed for moderate pump powers....

  17. Amphibian abnormalities on National Wildlife Refuges

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This fact sheet outlines a study done to 1) find the percentage of abnormal frogs and toads on the nation’s National Wildlife Refuges and 2) determine how the...

  18. Harbingers of Spring

    Science.gov (United States)

    Serrao, John

    1976-01-01

    Emphasizing the spring migration of frogs, toads, and salamanders to their watery breeding sites, this article presents information on numerous amphibians and suggests both indoor and outdoor educational activities appropriate for elementary and/or early secondary instruction. (JC)

  19. Valge fungi uus tulemine / Kersti Pikk

    Index Scriptorium Estoniae

    Pikk, Kersti

    2007-01-01

    Peeter Tambu projekteeritud valge "eestiaegne" funk eramu, kus avatud planeeringu asemel on paraja suurusega eraldi toad, esikohal ruumide otstarbekus ja ratsionaalsus. Arhitekt on kujundanud interjööri ja mööbli

  20. Effects of an insecticide on amphibians in large-scale experimental ponds

    Science.gov (United States)

    Boone, M.D.; Semlitsch, R.D.; Fairchild, J.F.; Rothermel, B.B.

    2004-01-01

    We examined the effects of the insecticide carbaryl on larval amphibian communities in large-scale experimental ponds. Tadpoles of two anurans, Woodhouse's toad (Bufo woodhousii) and southern leopard Frog (Rana sphenocephala), were reared in ponds (800 m3 volume) to determine the effects of tadpole density and carbaryl exposure on mass at metamorphosis and on time and survival to metamorphosis. Exposure to carbaryl significantly affected toads at metamorphosis, but not leopard frogs. Carbaryl exposure nearly doubled toad survival compared to controls; this effect may be attributable to an indirect effect of earbaryl increasing algal food resources. The competitive environment (i.e., density) and carbaryl exposure significantly affected the trade-off between mass and time to metamorphosis for toads. Our study is the first to demonstrate that in pond communities where predation and competition may be strong, short-lived insecticides can significantly alter the community dynamics of amphibians.

  1. Rahvusvahelisel muuseumipäeval 18. V avati Tartu Kunstimuuseumis Raekoja plats 18... / Reeli Kõiv

    Index Scriptorium Estoniae

    Kõiv, Reeli

    2005-01-01

    Näituse kuraator ülevaatenäitusest "Tartu kunsti lood", mis esitab Tartu kunsti arenguloo rohkem kui pooleteise sajandi lõikes. Näitusega kaasnevad muuseumitunnid ja töötoad igas vanuses lastele ja noortele

  2. Instruction Manual and Frog Survey Protocols for Region 1 National Wildlife Refuges, East-side Zone

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This manual is intended to assist biologists wishing to conduct surveys for frogs and toads. The document includes detailed information on how to conduct surveys,...

  3. Filmifestival õpetas ise filme looma / Aarne Mäe

    Index Scriptorium Estoniae

    Mäe, Aarne, 1967-

    1999-01-01

    30. sept. - 3. okt. Rakvere Exclusiveì ööklubis toimunud Põhjamaade ja Baltikumi noorte videofilmide filmifestivali "Visions of Light" raames tegutsesid ka töötoad : Eesti nukufilmi töötuba ja "Video netis"

  4. Trophic ecology and microhabitat utilization by the Bufo gargarizans, Rana guentheri, and Rana limnocharis in southwestern China

    OpenAIRE

    Tonglei Yu; Yanshu Guo

    2012-01-01

    We studied the trophic ecology and microhabitat use of the Asiatic toad, Bufo gargarizans Cantor, 1842; Guentheri frog, Rana guentheri (Boulenger, 1882); and the Ricefield frog, Rana limnocharis (Boie, 1834). These three species are common around Nanchong City, in southwestern China, where they live in the same habitat before hibernation. The main objective of this study was to analyze the diets and patterns of coexistence relative to the microhabitat of each species. In the Asiatic toad, bas...

  5. Can protected mountain areas serve as refuges for declining amphibians? Potential threats of climate change and amphibian chytridiomycosis in an alpine amphibian population. eco.mont (Journal on Protected Mountain Areas Research)|eco.mont Vol. 1 No. 2|

    OpenAIRE

    Sztatecsny, Marc; Hödl, Walter

    2009-01-01

    In June 2004 and June 2005, we checked 40 and 134 ponds respectively for alive and dead alpine newts, common toads, common frogs, and their clutches on the "Kirchfeld" plateau in the Northern Limestone Alps of Austria. We found several hundred dead common frogs and alpine newts in the two consecutive years and also observed an unusually high number of heterospecific matings between common toads and common frogs in 2004. In order to test whether the observed mortalities were caused by disease,...

  6. The herpetofauna of Timor-Leste: a first report

    OpenAIRE

    Hinrich Kaiser; Venancio Lopes Carvalho; Jester Ceballos; Paul Freed; Scott Heacox; Barbara Lester; Richards, Stephen J.; Trainor, Colin R.; Caitlin Sanchez; Mark O’Shea

    2011-01-01

    Abstract Fieldwork conducted throughout Timor-Leste in September 2004 and July 2009 resulted in a collection or recording of 263 herpetological specimens (100 amphibians, 163 reptiles), comprising at least seven species of frogs and toads, 20 species of lizards, seven species of snakes, two species of turtles, and one species of crocodile. Among the amphibians, the most frequently encountered species were toads ( Duttaphrynus melanostictus ), rice paddy frogs (genus Fejervarya ), and rhacopho...

  7. Use of stress-hormone levels and habitat selection to assess functional connectivity of a landscape for an amphibian.

    Science.gov (United States)

    Janin, Agnès; Léna, Jean-Paul; Deblois, Sandrine; Joly, Pierre

    2012-10-01

    The influence of landscape matrix on functional connectivity has been clearly established. Now methods to assess the effects of different land uses on species' movements are needed because current methods are often biased. The use of physiological parameters as indicators of the level of resistance to animal movement associated with different land uses (i.e., matrix resistance) could provide estimates of energetic costs and risks to animals migrating through the matrix. To assess whether corticosterone levels indicate matrix resistance, we conducted experiments on substrate choice and measured levels of corticosterone before and after exposure of toads (Bufo bufo) to 3 common substrates (ploughed soil, meadow, and forest litter). We expected matrix resistance and hormone levels to increase from forest litter (habitat of the toad) to meadows to ploughed soil. Adult toads had higher corticosterone levels on ploughed soil than on forest litter or meadow substrates. Hormone levels did not differ between forest litter and meadow. Toads avoided moving onto ploughed soil. Corticosterone levels in juvenile toads were not related to substrate type; however, hormone levels decreased as humidity increased. Juveniles, unlike adults, did not avoid moving over ploughed soil. The difference in responses between adult and juvenile toads may have been due to differences in experimental design (for juveniles, entire body used to measure corticosterone concentration; for adults, saliva alone); differences in the scale of sensory perception of the substrate (juveniles are much smaller than adults); or differences in cognitive processes between adult and juvenile toads. Adults probably had experience with different substrate types, whereas juveniles first emerging from the water probably did not. As a consequence, arable lands could act as ecological traps for juvenile toads. PMID:22891816

  8. Disease in a dynamic landscape: host behavior and wildfire reduce amphibian chytrid infection

    Science.gov (United States)

    Hossack, Blake R.; Lowe, Winsor H.; Ware, Joy L.; Corn, Paul Stephen

    2013-01-01

    Disturbances are often expected to magnify effects of disease, but these effects may depend on the ecology, behavior, and life history of both hosts and pathogens. In many ecosystems, wildfire is the dominant natural disturbance and thus could directly or indirectly affect dynamics of many diseases. To determine how probability of infection by the aquatic fungus Batrachochytrium dendrobatidis (Bd) varies relative to habitat use by individuals, wildfire, and host characteristics, we sampled 404 boreal toads (Anaxyrus boreas boreas) across Glacier National Park, Montana (USA). Bd causes chytridiomycosis, an emerging infectious disease linked with widespread amphibian declines, including the boreal toad. Probability of infection was similar for females and the combined group of males and juveniles. However, only 9% of terrestrial toads were infected compared to >30% of aquatic toads, and toads captured in recently burned areas were half as likely to be infected as toads in unburned areas. We suspect these large differences in infection reflect habitat choices by individuals that affect pathogen exposure and persistence, especially in burned forests where warm, arid conditions could limit Bd growth. Our results show that natural disturbances such as wildfire and the resulting diverse habitats can influence infection across large landscapes, potentially maintaining local refuges and host behaviors that facilitate evolution of disease resistance.

  9. Representaciones Sociales de la Historia Universal: Posicionamientos Diferenciales en Función de la Ideología Política, Religiosidad y Nacionalismo en una Muestra Argentina/RepresentationsSocial Representations of Universal History: Differential Positioning at the Service of Political Ideology, Religiosity and Nationalism in the Argentinian Context/Representações Sociais da História Universal: Posicionamentos Diferenciados em função da Ideologia Política, da Religiosidade e do Nacionalismo numa Amostra Argentina

    OpenAIRE

    Fernanda Mariel Sosa; Gisela Isabel Delfino; Magdalena Bobowik; Elena Mercedes Zubieta

    2016-01-01

    Con el objetivo de analizar las representaciones sociales de la historia a través de los sentimientos que despiertan 24 personajes de la historia universal, se administró una versión modificada del cuestionario construido por Liu et al. (2005) a una muestra intencional (n=369) de Argentina (55.7% mujeres, medad=36.20, deedad=11.16). El análisis de conglomerados no jerárquico arrojó 4 grupos en función de la religiosidad, el nacionalismo y el posicionamiento ideológico de los participantes. Po...

  10. Representaciones Sociales de la Historia Universal: Posicionamientos Diferenciales en Función de la Ideología Política, Religiosidad y Nacionalismo en una Muestra Argentina/RepresentationsSocial Representations of Universal History: Differential Positioning at the Service of Political Ideology, Religiosity and Nationalism in the Argentinian Context/Representações Sociais da História Universal: Posicionamentos Diferenciados em função da Ideologia Política, da Religiosidade e do Nacionalismo numa Amostra Argentina

    Directory of Open Access Journals (Sweden)

    Fernanda Mariel Sosa

    2016-03-01

    Full Text Available Con el objetivo de analizar las representaciones sociales de la historia a través de los sentimientos que despiertan 24 personajes de la historia universal, se administró una versión modificada del cuestionario construido por Liu et al. (2005 a una muestra intencional (n=369 de Argentina (55.7% mujeres, medad=36.20, deedad=11.16. El análisis de conglomerados no jerárquico arrojó 4 grupos en función de la religiosidad, el nacionalismo y el posicionamiento ideológico de los participantes. Por su parte, del análisis de clúster jerárquico, en función de los sentimientos hacia los personajes, se desprendieron 2 conglomerados denominados héroes y villanos. Los personajes religiosos y políticos son los que mayor disenso suscitan.

  11. Dante e i lettori argentini: l'interpretazione politica della Commedia

    Directory of Open Access Journals (Sweden)

    Claudia Fernández Speier

    2014-12-01

    The relationship between Dante and Argentinian readers dates back to the first half of the 19th century. In agreement with the romantic interpretation that caracterised its reading in Italy, they saw in the Divine Comedy, above all, the values of political freedom and national unity. Conceived as a universal work, deprived of its more Italian and medieval traits, from then on the poem was read in Argentina as a universal and timeless book, capable of recieving every historical context. This work attempts to retrace the process of political appropriation underwent by Dante’s Comedy through two centuries. We concentrate on the characteristics of its circulation in each period, and we identify the ideological and aesthetic values it has trasmitted in the Argentinian literary field, in relation with the different aspects of the local reality connected with the poem.

  12. The Test Observation of Electrical Physiology about the Exhausted Recovery of a Toad's Calf Intestines Muscle Specimen by Acupuncture%关于针刺对蟾蜍腓肠肌标本疲劳恢复的电生理实验观察

    Institute of Scientific and Technical Information of China (English)

    黄琰

    2002-01-01

    以蟾蜍为实验对象,对蟾蜍腓肠肌标本进行电刺激收缩达到一定的疲劳程度后,分别采取休息和针刺方法恢复,观察整个过程中的肌肉收缩曲线并分析.实验结果显示:针刺可以大幅度地提高肌肉在疲劳后恢复中的最大用力.

  13. Absence of tetrodotoxins in a captive-raised riparian frog, Atelopus varius.

    Science.gov (United States)

    Daly, J W; Padgett, W L; Saunders, R L; Cover, J F

    1997-05-01

    Bufonid frogs of the genus Atelopus contain two classes of skin toxins, namely the steroidal bufadienolides and the water-soluble tetrodotoxins. Frogs of the Panamanian species Atelopus varius have now been raised in captivity and levels in skin extracts of bufadienolides and of tetrodotoxin-like compounds assessed, using inhibition of [3H]ouabain binding and inhibition of [3H]saxitoxin binding, respectively. Levels of ouabain equivalents, corresponding to bufadienolides, were comparable to those found in wild-caught frogs from the same population in Panama, while tetrodotoxin-like activity was undetectable. The results strongly implicate environmental factors, perhaps symbiotic microorganisms, in the genesis of tetrodotoxins in the skin of frogs of the genus Atelopus, while indicating that the frog itself produces the skin bufadienolides. PMID:9203295

  14. Sociologia, peronismo e esquerda na Argentina Sociology, peronism and left in Argentina

    OpenAIRE

    Carlos R. Etulain

    2007-01-01

    O trabalho discute, o papel do peronismo e os problemas político-ideológicos que ele coloca para a esquerda Argentina. Busca, também, apresentar os principais elementos para uma análise da esquerda frente ao fenômeno do peronismo. Palavras-chave: Peronismo. Esquerda. Trabalhadores. Movimentos sociais. Classes sociais. Capitalismo. Política. This paper presents the role of Peronism and the ideological political problems to be confronted by the Argentinian leftists...

  15. Revisiting Germani: the interpretation of modernity and the theory of action

    OpenAIRE

    José Maurício Domingues; María Maneiro; Deborah Neale

    2005-01-01

    The work of the Italo-Argentinian sociologist Gino Germani has traditionally been classified as functionalist. However, recent studies have tended to change this perspective, emphasizing other important influences in his work. Against the backdrop of his broader theory, the objective of this article is to analyze, on the one hand, his perception, in the Latin American transition to modernity, of freedom as the essential issue in politics and daily life, and on the other, how this translates i...

  16. A través de la yerba mate: etnicidad y racionalidad económica entre los trabajadores rurales paraguayos en la industria de la construcción de Buenos Aires

    Directory of Open Access Journals (Sweden)

    Álvaro del Águila

    2014-04-01

    Full Text Available This article analyzes the process by which rural workers migrate from Paraguay to work in the Argentinian construction industry. There is some evidence that the migration process changes not only the lives of migrants but, in a profound way, their economic rationality. Employing an ethnographic perspective we contrast the work experiences of Paraguayan migrants at origin and at their point of arrival. The article casts light on the profound overlap between ethnicity, work and economic rationality.

  17. Azar y psicoanálisis: Una interpretación del sueño en nadie nada nunca de Juan José Saer

    OpenAIRE

    Degrande, François

    2014-01-01

    . Our reading attempts to shed light on the literary project of the Argentinian writer as he plots the improbable relation of chance and psychoanalysis in his fifth novel, Nadie nada nunca. In this vein, the problematic coexistence of causality and chance can only be explained by the dictatorial terror that permeates this novel. To prove this, the article analyzes the oneiric world of El Gato (II), in which the freudian principle of condensation turns a bawdy house into a casino. This crucial...

  18. Erythromycin-Resistant Streptococcus pyogenes in Argentina Resistencia a la eritromicina en Streptococcus pyogenes en la Argentina

    OpenAIRE

    Lopardo, Horacio A.; Claudia Hernandez; Patricia Vidal; Miryam Vazquez; Liliana Rosaenz; Gabriela Rubinstein; Jorgelina Smayevsky; Marta Tokumoto; Adriana Fernandez Lausi; Omar Daher; Sara Kaufman; Silvia V. Soriano; Susana Brasili; Marina Bottiglieri; Maria Cristina Carranza

    2004-01-01

    Erythromycin (ERY) resistance in Streptococcus pyogenes has recently emerged as a problem of growing concern all through the world. We are presenting the comparison of results of the continuous surveillance of erythromycin resistance in S. pyogenes performed since 1989 in the Hospital de Pediatría J.P.Garrahan of Buenos Aires City, with independently observed rates in other five centers of Buenos Aires and seven centers of six other Argentinian cities, obtained between 1999 and 2001. A signif...

  19. Antarctic network of lamp-calibrated multichannel radiometers for continuous ozone and uv radiation data

    OpenAIRE

    Redondas, A.; Torres, C.; O. Meinander; K. Lakkala; R. García; E. Cuevas; Ochoa, H.; Deferrari, G.; Díaz, S.

    2008-01-01

    Three NILU-UV multichannel radiometers have been installed in 1999 at the Argentinian sites of Ushuaia (54S), Marambio (64S) and Belgrano-II (77S) in order to continuously monitor UV radiation, photosynthetically active radiation and total ozone. The measurements were established by INM, Spain in collaboration with FMI, Finland, DNA-IAA, Argentina and CADIC, Argentina to observe and characterize the spatial and temporal evolution of ozone and ultraviolet radiation in the Antarctic region. Spe...

  20. El liberalismo conservador y la ideología del Proceso de Reorganización Nacional

    Directory of Open Access Journals (Sweden)

    Sergio Morresi

    2010-06-01

    Full Text Available This article aims to show that the political ideas of the selfnamed "National Reorganization Process -Proceso de Reorganización Nacional [PRN]" -were structured within the ideological frame offered by conservative-liberalism. Through the study of some of the ideologicalpromoters of the PRN, it is argued that conservative-liberalism served as merger of the different types of argentinian rights and laid the foundations for the neoliberal ideas that were impelled afer the dictatorship period

  1. La invención de los ancestros: el «patagón antiguo» y la construcción discursiva de un pasado nacional remoto para la Argentina (1870-1915

    Directory of Open Access Journals (Sweden)

    Navarro Floria, Pedro

    2004-08-01

    Full Text Available We intend to demonstrate that the existence of an «Antique Patagon» was an idea stemming from the political need —at the end of the 19th Century— of imagining a remote past for the young Argentinian nation. This article studies in historical context a group of anthropological writings of the 1870’s and 1880’s. Firstly, those of the Argentinian F.P. Moreno and the German-Argentinian H. Burmeister. Secondly, those of the Argentinian E. Zeballos. The former show the relation between nationalist interests and the scientifical debates of the time; the latter are the historical narrative corresponding to those interests.

    Nos proponemos demostrar que la idea de la existencia de un «patagón antiguo» respondió a la necesidad política de imaginar, a fines del siglo XIX, un pasado remoto para la joven nación argentina. Estudiamos en su contexto histórico una serie de trabajos antropológicos de las décadas de 1870 y 1880, del argentino F.P. Moreno y del alemán-argentino H. Burmeister, y de escritos de divulgación del argentino E.S. Zeballos. Los primeros muestran la relación entre los intereses nacionalistas y los debates científicos vigentes en la época; los segundos constituyen el relato histórico funcional a aquellos intereses.

  2. Las armas de la conquista. Presencia de armas de fuego en sitios coloniales de Argentina

    OpenAIRE

    Ana Igareta; Vanina Castillón

    2013-01-01

    Objects used as weapons by the man had interested archaeologists worldwide since the early times of the discipline. Cultural sequences had been defined using the evolution arms as one of the relevant material indicators of social development. Argentinian archaeology has an extensive tradition of prehistoric weapons studies, but little attention has been accorded to the repertoire of arms -particulary firearmsused during colonial confrontations between Spanish soldiers and nativ...

  3. Wladimiro Acosta y la vivienda colectiva (1928 - 1935) : su aporte a la innovación arqueológica y tipológica en América Latina

    OpenAIRE

    Ranzini, Marcelo

    2015-01-01

    VVladimiro Acosta (WA) was a Russian architect with centro-european modem studies. His moving to Latin America in 1928 he meant one of the most significant contributions to Argentinian architecture. Since his arrival until 1935 he would develop ten social housing prototypes, which although they were never built they still represent one of the main and most complete studies on housing unit. The hypothesis which leads this thesis shows these prototypes as one of the most significant contributio...

  4. Zulma Ageitos de Castellanos: Publications and status of described taxa.

    Science.gov (United States)

    Signorelli, Javier H; Urteaga, Diego; Teso, Valeria

    2015-10-28

    Zulma Ageitos de Castellanos was an Argentinian malacologist working in the "Facultad de Ciencias Naturales y Museo" at La Plata University where she taught invertebrate zoology between 1947 and 1990. Her scientific publications are listed in chronological order. Described genus-group and species-group taxa are listed. Information about the type locality and type material, and taxonomic remarks are also provided. Finally, type material of all described taxa was requested and, when located, illustrated.

  5. Outsourcing central banking

    DEFF Research Database (Denmark)

    Khoury, Sarkis Joseph; Wihlborg, Clas

    2005-01-01

    The literature on Currency Boards (CB) stops at the water edge in terms of dealing with the totality of the functions of a central bank. Monetary policy, and banking supervisioncan be "outsourced" in an open economy with substantial foreign direct investment (FDI)in the banking sector if political...... the feasibility of, and constraints on, outsourcing of central bank functions. A brief discussion of the Argentinian experience is used for contrast.Key words: Currency Board, Foreign Banks, Supervision, Regional Integration,outsourcing....

  6. Los caracteres morfológicos del controvertido Neobatrachia arborícola Allophryne ruthveni Gaige, 1926

    Directory of Open Access Journals (Sweden)

    Fabrezi, Marissa

    2000-07-01

    Full Text Available Allophtyne ruthveni es un anuro neotropical arborícola asignado a una familia monotípica. Aunque sus afinidades con otros taxa permanecen sin precisar, durante mucho tiempo se lo relacionó con los anuros arborícolas neotropicales, aún cuando la ausencia de dientes, característica de los Bufonidae, fue el primer argumento para establecer alguna relación con estos. En el presente trabajo, presentamos un re-análisis de caracteres esqueléticos y miológicos de A. ruthveni a partir del cual encontramos ausencia de elementos intercalares, típicos de formas arborícolas; algunos rasgos compartidos con los bufónidos; y numerosos caracteres presentes en distintos neobatracios que deberían ser discutidos sobre la base de un análisis filogenético. Finalmente, consideramos dos características distintivas de las extremidades de A. ruthveni. Allophryne ruthveni is a neotropical arboreous frog assigned to a monotypical family. Although A. ruthveni's relationships remain poorly known, most of authors searched relationships with neotropical treefrogs in spite of the absence of teeth was an early evidence to relate it with bufonids. Herein, we presented a new analysis of osteological and some myological traits of A. ruthveni. Intercallary elements, related to the arboreal life style similar lo that present in neotropical treefrogs such as hylids, is very different in A. ruthveni; some cranial features of A. ruthveni represent traits shared with bufonids, and many morphological characters also are present among neobatracians. However, they can not be interpreted without a phylogenetic analysis. Finally, we considered two specific limb features of A. ruthveni.

  7. A New Time-Based Algorithm for Positioning Mobile Terminals in Wireless Networks

    Directory of Open Access Journals (Sweden)

    Francisco Barcelo-Arroyo

    2008-03-01

    Full Text Available This paper presents a positioning algorithm, named time of arrival to time difference of arrival (TOAD, which computes time-difference-of-arrival (TDOA measurements from the messages that time-of-arrival (TOA stations in sight exchange while their positioning processes are running. This study addresses the accuracy of the TOAD algorithm in two different environments: line-of-sight (LOS and non-line-of-sight (NLOS. Simulation is used to set up a wireless network. The Gauss-Newton nonlinear least squares algorithm is used to compute the positions in both TOA and TOAD stations. Results indicate that the TOAD algorithm increases the root mean square error (RMSE of the positioning error in LOS scenarios by 10 to 20% compared with the RMSE achieved by TOA. This drop in accuracy contrasts with the results for the NLOS scenarios. The RMSE of TOAD in such scenarios is at least 10% lower than that achieved by TOA. This result is specially important since this latter scenario is the most common. Consequently, this novel technique therefore improves the scalability and integrity of TOA techniques based on RTT, making it possible for the stations to position themselves without injecting traffic and with QoS figures close and most times better than that achieved by TOA.

  8. Desiccation risk drives the spatial ecology of an invasive anuran (Rhinella marina in the Australian semi-desert.

    Directory of Open Access Journals (Sweden)

    Reid Tingley

    Full Text Available Some invasive species flourish in places that impose challenges very different from those faced in their native geographic ranges. Cane toads (Rhinella marina are native to tropical and subtropical habitats of South and Central America, but have colonised extremely arid regions over the course of their Australian invasion. We radio-tracked 44 adult cane toads at a semi-arid invasion front to investigate how this invasive anuran has managed to expand its geographic range into arid areas that lie outside of its native climatic niche. As predicted from their low physiological control over rates of evaporative water loss, toads selected diurnal shelter sites that were consistently cooler and damper (and thus, conferred lower water loss rates than nearby random sites. Desiccation risk also had a profound influence on rates of daily movement. Under wet conditions, toads that were far from water moved further between shelter sites than did conspecifics that remained close to water, presumably in an attempt to reach permanent water sources. However, this relationship was reversed under dry conditions, such that only toads that were close to permanent water bodies made substantial daily movements. Toads that were far from water bodies also travelled along straighter paths than did conspecifics that generally remained close to water. Thus, behavioural flexibility--in particular, an ability to exploit spatial and temporal heterogeneity in the availability of moist conditions--has allowed this invasive anuran to successfully colonize arid habitats in Australia. This finding illustrates that risk assessment protocols need to recognise that under some circumstances an introduced species may be able to thrive in conditions far removed from any that it experiences in its native range.

  9. All-optical adder/subtractor based on tera-hertz optical asymmetric demultiplexer

    Institute of Scientific and Technical Information of China (English)

    Dilip Kumar Gayen; Rajat Kumar Pal; Jitendra Nath Roy

    2009-01-01

    An all-optical adder/subtractor (A/S) unit with the help of terahertz optical asymmetric demultiplexer (TOAD) is proposed.Tile all-optical A/S unit with a set of all-optical full-adders and optical exclusive-ORs (XORs),can be used to perform a fast central processor unit using optical hardware components.We try to exploit the advantages of TOAD-based optical switch to design an integrated all-optical circuit which can perform binary addition and subtraction.With computer simulation results confirming the described methods,conclusions are given.

  10. Výskyt a biotopové preference obojživelníků na bývalém tankovém cvičišti u Českých Budějovic

    OpenAIRE

    NĚMEC, Stanislav

    2011-01-01

    Submitted bachelor thesis deals with biotope preferences of amphibians. Experimental part of my work was carried out at former military tank ground near České Budějovice from March until June 2010. Biotope preferences were examined at these species: European Fire-bellied Toad, European tree frog, Agile Frog and Common toad. Since the end of military activity in 1990, there has been growing ecological succession which influences each of the species. The aim of my work was to find out what fact...

  11. "mina usun sõna..." : [luuletused] / Maarja Kangro, Mart Kangur, Lauri Kitsnik jt

    Index Scriptorium Estoniae

    2007-01-01

    Sisu: "mina usun sõna..." ; Tüdruk heitis mulle silma (Silmapartii) ; "Helista siis mulle. Hoolimata sellest, mis kell ma täna magama..." ; Tärkab ; Toad ; "Tee sees on augud. Maa sees on augud..." ; "Puuk on perses. Ai-ai, valus on..." ; Päärätik ; Pliidikütt ; "Ukrainlannast põetaja..." ; Stereonurr ; "Luuletused..."

  12. Our Zoo to You

    Science.gov (United States)

    Wickless, Mimi; Brooks, David W.; Abuloum, Amjad; Mancuso, Brian; Heng-Moss, Tiffany M.; Mayo, Lois

    2003-01-01

    An innovative zoo outreach program, Our Zoo to You, places zoo animals in local classrooms for extended observation periods. With guidance and support from zoo staff, students are able to safely experience a variety of animals, including geckos, snakes, legless lizards, horned toads, ringneck doves, ferrets, hedgehogs, African brown millipedes,…

  13. Kassinurme mägedes toimusid Elendili päeva pidustused ehk Tolkieni sõprade suvelaager / Ilmar Pajumägi

    Index Scriptorium Estoniae

    Pajumägi, Ilmar

    2005-01-01

    J. R. R. Tolkieni triloogia "Sõrmuste isand" sai tänavu 50 aastaseks. Sellega seoses korraldasid muinasjutusõbrad 18.-21. aug. Jõgeva lähedal Kassinurme mägedes LARPi (Live Action Role Play). Toimusid ka mitmed teemaga seotud töötoad, õpitoad ja loengud

  14. Täpne arhitektuur : ACADIA aastakonverents Cooper Unioni arhitektuurikoolis / Veronika Valk

    Index Scriptorium Estoniae

    Valk, Veronika, 1976-

    2010-01-01

    Septembris 2010 toimunud ACADIA aastakonverentsist New Yorgis. Konverents, töötoad ja näitus pakkusid parameetrilise projekteerimise spetsialistidele üle maailma lava, kus arhitektuuri uusi suundi arutada ja oma praktika üle mõtteid vahetada

  15. Effect of atrazine and fenitrothion at no-observed-effect-levels (NOEL) on amphibian and mammalian corticosterone-binding-globulin (CBG).

    Science.gov (United States)

    Hernández, Sandra E; Sernia, Conrad; Bradley, Adrian J

    2014-11-01

    This study determines the effect of atrazine and fenitrothion no-observed-effect-levels (NOEL) on the binding of corticosterone (B) to corticosterone-binding-globulin (CBG) in an amphibian and a mammal. Plasma from five cane toads and five Wistar rats was exposed to atrazine and fenitrothion at the NOEL approved for Australian fresh water residues and by the World Health Organization (WHO). The concentration required to displace 50% (IC50) of B binding to CBG was determined by a competitive microdialysis protein assay. Competition studies showed that both atrazine and fenitrothion at NOEL are able to compete with B for CBG binding sites in toad and rat plasma. The IC50 levels for atrazine in toads and rats were 0.004 nmol/l and 0.09 nmol/l respectively. In the case of fenitrothion the IC50 level found in toads was 0.007 nmol/l, and 0.025 nmol/l in rats. Plasma dilution curves showed parallelism with the curve of B, demonstrating that these agro-chemicals are competitively inhibiting binding to CBG. The displacement of B by atrazine and fenitrothion would affect the total:free ratio of B and consequently disrupt the normal stress response. This is the first time that the potential disruptive effect of atrazine and fenitrothion on B-CBG interaction at the NOELs has been demonstrated in amphibian and mammalian models.

  16. Proton pump activity is required for active uptake of chloride in isolated amphibian skin exposed to freshwater

    DEFF Research Database (Denmark)

    Jensen, Lars Jørn; Willumsen, Niels J.; Larsen, Erik Hviid

    2002-01-01

    Net proton secretion and unidirectional chloride fluxes were measured in isolated skin of toads (Bufo bufo) and frogs (Rana esculenta) mounted in an Ussing chamber and exposed to a Ringer's solution on the serosal side and a freshwater-like solution (1-3 mM Cl-) on the external side. Active proto...

  17. What Do Amphibians Have to Offer?: Students Monitor and Map Amphibians in Local Pond Habitats

    Science.gov (United States)

    Eareckson, Lee Anne

    2002-01-01

    Students value participation in meaningful research. They feel empowered when they effect positive change in their communities. They also have a strong affinity for frogs and toads, although they vehemently deny this at the start of the school year. In addition, most students recognize the value of using computer technology to solve world…

  18. All about Amphibians. Animal Life for Children. [Videotape].

    Science.gov (United States)

    2000

    This videotape teaches children about their favorite amphibious creatures, as well as amphibians' nearest cousins--toads, newts, and salamanders. Young students discover how these amazing creatures can live both in and out of water, learn about the amphibious life cycle, and compare the differences between amphibians and reptiles. This videotape…

  19. Microelectronic neural bridge for signal regeneration and function rebuilding over two separate nerves

    Science.gov (United States)

    Xiaoyan, Shen; Zhigong, Wang; Xiaoying, Lü; Shushan, Xie; Zonghao, Huang

    2011-06-01

    According to the feature of neural signals, a micro-electronic neural bridge (MENB) has been designed. It consists of two electrode arrays for neural signal detection and functional electrical stimulation (FES), and a microelectronic circuit for signal amplifying, processing, and FES driving. The core of the system is realized in 0.5-μm CMOS technology and used in animal experiments. A special experimental strategy has been designed to demonstrate the feasibility of the system. With the help of the MENB, the withdrawal reflex function of the left/right leg of one spinal toad has been rebuilt in the corresponding leg of another spinal toad. According to the coherence analysis between the source and regenerated neural signals, the controlled spinal toad's sciatic nerve signal is delayed by 0.72 ms in relation to the sciatic nerve signal of the source spinal toad and the cross-correlation function reaches a value of 0.73. This shows that the regenerated signal is correlated with the source sciatic signal significantly and the neural activities involved in reflex function have been regenerated. The experiment demonstrates that the MENB is useful in rebuilding the neural function between nerves of different bodies.

  20. Microelectronic neural bridge for signal regeneration and function rebuilding over two separate nerves*

    Institute of Scientific and Technical Information of China (English)

    Shen Xiaoyan; Wang Zhigong; Lü Xiaoying; Xie Shushan; Huang Zonghao

    2011-01-01

    According to the feature of neural signals, a micro-electronic neural bridge (MENB) has been designed.It consists of two electrode arrays for neural signal detection and functional electrical stimulation (FES), and a microelectronic circuit for signal amplifying, processing, and FES driving. The core of the system is realized in 0.5-μm CMOS technology and used in animal experiments. A special experimental strategy has been designed to demonstrate the feasibility of the system. With the help of the MENB, the withdrawal reflex function of the left/right leg of one spinal toad has been rebuilt in the corresponding leg of another spinal toad. According to the coherence analysis between the source and regenerated neural signals, the controlled spinal toad's sciatic nerve signal is delayed by 0.72 ms in relation to the sciatic nerve signal of the source spinal toad and the cross-correlation function reaches a value of 0.73. This shows that the regenerated signal is correlated with the source sciatic signal significantly and the neural activities involved in reflex function have been regenerated. The experiment demonstrates that the MENB is useful in rebuilding the neural function between nerves of different bodies.

  1. Microelectronic neural bridge for signal regeneration and function rebuilding over two separate nerves

    Energy Technology Data Exchange (ETDEWEB)

    Shen Xiaoyan; Wang Zhigong; Xie Shushan; Huang Zonghao [Institute of RF- and OE-ICs, Southeast University, Nanjing 210096 (China); Lue Xiaoying, E-mail: zgwang@seu.edu.cn [Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096 (China)

    2011-06-15

    According to the feature of neural signals, a micro-electronic neural bridge (MENB) has been designed. It consists of two electrode arrays for neural signal detection and functional electrical stimulation (FES), and a microelectronic circuit for signal amplifying, processing, and FES driving. The core of the system is realized in 0.5-{mu}m CMOS technology and used in animal experiments. A special experimental strategy has been designed to demonstrate the feasibility of the system. With the help of the MENB, the withdrawal reflex function of the left/right leg of one spinal toad has been rebuilt in the corresponding leg of another spinal toad. According to the coherence analysis between the source and regenerated neural signals, the controlled spinal toad's sciatic nerve signal is delayed by 0.72 ms in relation to the sciatic nerve signal of the source spinal toad and the cross-correlation function reaches a value of 0.73. This shows that the regenerated signal is correlated with the source sciatic signal significantly and the neural activities involved in reflex function have been regenerated. The experiment demonstrates that the MENB is useful in rebuilding the neural function between nerves of different bodies. (semiconductor integrated circuits)

  2. Responding to Amphibian Loss

    NARCIS (Netherlands)

    J.R. Mendelson III; K.R. Lips; R.W. Gagliardo; G.B. Rabb; J.P. Collins; J.E. Diffendorfer; P. Daszak; R. Ibáñez D.; K.C. Zippel; D.P. Lawson; K.M. Wright; S.N. Stuart; C. Gascon; H.R. da Silva; P.A. Burrowes; R.L. Joglar; E. La Marca; S. Lötters; L.H. du Preez; C. Weldon; A. Hyatt; J.V. Rodriguez-Mahecha; S. Hunt; H. Robertson; B. Lock; C.J. Raxworthy; D.R. Frost; R.C. Lacy; R.A. Alford; J.A. Campbell; G. Parra-Olea; F. Bolaños; J.J. Calvo Domingo; T. Halliday; J.B. Murphy; M.H. Wake; L.A. Coloma; S.L. Kuzmin; M.S. Price; K.M. Howell; M. Lau; R. Pethiyagoda; M. Boone; M.J. Lannoo; A.R. Blaustein; A. Dobson; R.A. Griffiths; M.L. Crump; D.B. Wake; E.D. Brodie Jr

    2006-01-01

    In their Policy Forum "Confronting amphibian declines and extinctions" (7 July, p. 48), J. R. Mendelson III and colleagues offer a strategy for "stopping" the widespread losses of frogs, toads, and salamanders. Disease research and captive breeding figure prominently in their call for action.

  3. Vertebral number is highly evolvable in salamanders and newts (family Salamandridae) and variably associated with climatic parameters

    NARCIS (Netherlands)

    Arntzen, J.W.; Beukema, W.; Galis, F.; Ivanović, A.

    2015-01-01

    In vertebrates, the relative proportion of the number of trunk and caudal vertebrae is an important determinant of body shape. While among amphibians frogs and toads show low variation in vertebrae numbers, in salamanders the numbers of trunk and caudal vertebrae vary widely, giving rise to phenotyp

  4. MRI zoo

    DEFF Research Database (Denmark)

    Laustsen, Christoffer

    The basic idea was to use MRI to produce a sequence of 3D gray scale image slices of various animals, subsequentlyimaged with a clinical CT system. For this purpose, these animals were used: toad, lungfish, python snake and a horseshoe crab. Each animal was sacrificed according to standard proced...

  5. 76 FR 78805 - Airworthiness Directives; Rolls-Royce plc (RR) RB211-Trent 800 Series Turbofan Engines

    Science.gov (United States)

    2011-12-20

    ... Register on August 22, 2011 (76 FR 52288). That NPRM proposed to correct an unsafe condition for the.... American also asserted that the estimate in the NPRM (76 FR 52288, August 22, 2011) of labor hours to...-AD685, which are referenced in the NPRM (76 FR 52288), do not include inspection criteria for the...

  6. Membrane interaction and antibacterial properties of two mildly cationic peptide diastereomers, bombinins H2 and H4, isolated from Bombina skin

    NARCIS (Netherlands)

    C. Coccia; A.C. Rinaldi; V. Luca; D. Barra; A. Bozzi; A. Di Giulio; E.C.I. Veerman; M.L. Mangoni

    2011-01-01

    Bombinins H are mildly cationic antimicrobial peptides isolated from the skin of the anuran genus Bombina, the fire-bellied toad. Some members of this peptide family coexist in skin secretions as diastereomers in which a single D-amino acid (alloisoleucine or leucine) is incorporated as a result of

  7. Feleucins: Novel Bombinin Precursor-Encoded Nonapeptide Amides from the Skin Secretion of Bombina variegata

    Directory of Open Access Journals (Sweden)

    Bing Bai

    2014-01-01

    Full Text Available The first amphibian skin antimicrobial peptide (AMP to be identified was named bombinin, reflecting its origin from the skin of the European yellow-bellied toad (Bombina variegata. Bombinins and their related peptides, the bombinin Hs, were subsequently reported from other bombinid toads. Molecular cloning of bombinin-encoding cDNAs from skin found that bombinins and bombinin Hs were coencoded on the same precursor proteins. Here, we report the molecular cloning of two novel cDNAs from a skin secretion-derived cDNA library of B. variegata whose open-reading frames each encode a novel bombinin (GIGGALLNVGKVALKGLAKGLAEHFANamide and a C-terminally located single copy of a novel nonapeptide (FLGLLGGLLamide or FLGLIGSLLamide. These novel nonapeptides were named feleucin-BV1 and feleucin-BV2, respectively. The novel bombinin exhibited 89% identity to homologues from the toads, B. microdeladigitora and B. maxima. The feleucins exhibited no identity with any amphibian AMP archived in databases. Synthetic feleucins exhibited a weak activity against Staphylococcus aureus (128–256 mg/L but feleucin-BV1 exhibited a synergistic action with the novel bombinin. The present report clearly demonstrates that the skin secretions of bombinid toads continue to represent a source of peptides of novel structure that could provide templates for the design of therapeutics.

  8. Plasticity in the melanotrope neuroendocrine interface of Xenopus laevis

    NARCIS (Netherlands)

    Jenks, B.G.; Kidane, A.H.; Scheenen, W.J.; Roubos, E.W.

    2007-01-01

    Melanotrope cells of the amphibian pituitary pars intermedia produce alpha-melanophore-stimulating hormone (alpha-MSH), a peptide which causes skin darkening during adaptation to a dark background. The secretory activity of the melanotrope of the South African clawed toad Xenopus laevis is regulated

  9. Myths.

    Science.gov (United States)

    Wheat, Maxwell Corydon, Jr.

    1982-01-01

    Deals with various myths about animals and plants. Discusses bats (not blind), toads (do not cause warts), dragonflies (will not sew up your mouth), horseshoe crabs (will not sting with their tails), owls (not so smart), and goldenrod (does not cause hayfever). (MH)

  10. Records of Sandflies (Diptera: Psychodidae: Phlebotominae feeding on Amphibia, with A new record from the Kruger National Park

    Directory of Open Access Journals (Sweden)

    H. H Braack

    1981-01-01

    Full Text Available An early record of a sandfly feeding on an amphibian is that of Hewlett (1913, Indian J. med. Res. 1: 34-38 who wrote "I have twice seen a sandfly apparently biting the head of the common toad Bufo melanostictus".

  11. Historical biogeography of Western Palaearctic pelobatid and pelodytid frogs: a molecular phylogenetic perspective

    NARCIS (Netherlands)

    Veith, M.; Fromhage, L.; Kosuch, J.; Vences, M.

    2006-01-01

    Spadefoot toads (Pelobates) and Parsley frogs (Pelodytes) are an enigmatic group of Western Palaearctic anurans. In the genus Pelobates, a fossorial lifestyle has enforced a conserved bauplan that masks their intraspecific evolutionary history. We used partial sequences of the mitochondrial 16S and

  12. New Host and Distribution Records of the Leech Placobdella sophieaeOceguera-Figueroa et al., 2010 (Hirudinida: Glossiphoniidae)

    Science.gov (United States)

    Moser, William E.; Bowerman, Jay; Hovingh, Peter; Pearl, Christopher A.; Oceguera-Figueroa, Alajandro

    2014-01-01

    Placobdella sophieae Oceguera-Figueroa et al., 2010 (Hirudinida: Glossiphoniidae) is reported from Oregon, California, and British Columbia for the first time. New hosts reported for P. sophieae include Taricha granulosa (rough-skinned newt), Rana pretiosa (Oregon spotted frog), and Anaxyrus boreas (western toad). Placobdella sophieae exhibits relatively low host specificity and all amphibians occurring in the Pacific Northwest are potential hosts.

  13. Further report of the occurrence of tetrodotoxin in Atelopus species (family: Bufonidae).

    Science.gov (United States)

    Mebs, D; Yotsu-Yamashita, M; Yasumoto, T; Lötters, S; Schlüter, A

    1995-02-01

    In alcoholic extracts from museum samples of the toads Atelopus subornatus and A. peruensis tetrodotoxin and its analogues, 4-epitetrodotoxin and 4,9-anhydrotetrodotoxin were detected by fluorometric HPLC analysis, extending the list of amphibians containing this toxin. However, the toxin was not detected in samples of Melanophryniscus stelzneri, Dendrophryniscus minutus and Oreophrynella sp. PMID:7597728

  14. La identidad lingüística argentina a través de Borges y Puig

    Directory of Open Access Journals (Sweden)

    Thon, Sonia

    2010-02-01

    Full Text Available The identity of the Argentinian linguistic expression has been studied in depth by many literary critics and linguists who demonstrated the close relationship that exists between language, ideology, and socio-historic context; especially, when incorporating the concept of oral and colloquial language to the narrative discourse. We are basing this paper on the studies of authors such as: Beatriz Sarlo, Walter Bruno Berg, Wolf Oesterreicher, Maria Zulema Kulikowsi, and others in order to situate two Argentinian writers, Jorge Luis Borges and Manuel Puig, within their historic period in order to reveal how their personal and social anxieties impacted the perception of their work as representative of the Argentinian language.

    La identidad de la expresión lingüistica argentina ha sido estudiada a fondo por numerosos críticos literarios y lingüistas que demostraron la estrecha relación que existe entre lengua, ideología y contexto socio-histórico, especialmente al incorporarse al discurso narrativo el concepto de oralidad y “coloquialidad”. En este ensayo nos basaremos en estudios de autores tales como Beatriz Sarlo, Walter Bruno Berg, Wolf Oesterreicher, María Zulema Kulikowski, entre otros, para situar a dos escritores argentinos, Jorge Luis Borges y Manuel Puig, dentro de su época y revelar cómo sus ansiedades personales y sociales impactaron la percepción de su obra como representativa de lo que se considera el lenguaje argentino.

  15. El poder de la prensa, la prensa del poder : reflexión entorno al periodismo afroargentino

    Directory of Open Access Journals (Sweden)

    Jean Arsène Yao

    2004-09-01

    Full Text Available Le grand développement de la presse qui se produisit en Argentine à partir de 1850 se caractérisa en particulier par l'émergence d'une presse afro-argentine très active, dont l'objectif était de défendre les intérêts de la communauté noire. Cet article essaie de déterminer si les Argentins d'origine africaine prirent conscience du pouvoir de la presse écrite, comme moyen de divulgation de leurs idées. Par ailleurs, il met en évidence les accointances des journaux afroargentins avec la classe politique de l'époque, démontrant ainsi à quel point ils furent instrumentalisés par le pouvoir en place.El despegue periodístico que se produjo en Argentina durante la década de 1850 vio la aparición de una activa prensa afroargentina defensora de los intereses de la comunidad negra. Este artículo pretende analizar en qué medida los argentinos de origen africano fueron conscientes del poder de la prensa escrita como medio de divulgación de sus ideas. Subraya por otra parte el acercamiento de los periódicos afroargentinos a la clase política convirtiéndose en instrumentos del poder político.In the 1850's appeared an Afro-Argentinian activist press, which defended the black community interests. In this paper the author tries to evaluate if the Argentinians of African origin realized the full power of the written press as a way of spreading their ideas.Therefore, he explains the conversion of the Afro-Argentinians newspapers as political instruments.

  16. National Agriculture Society (SNA and fruit-crops development in Chile, 1838- 1933

    Directory of Open Access Journals (Sweden)

    Pablo Lacoste

    2013-06-01

    Full Text Available Since its beginning in 1938, the National Agriculture Society (SNA began publishing journals with agriculture-related topics. This generated a singular feature-length documentary from which those devoted to fruit growing are examined in this work. Three-hundred articles referred to plant’s cultivation practices, diseases and pests infestations, fruit conservation, and the export business. North American and Argentinian, among others, references are mentioned in these articles. The SNA contributions to fruit-crops growing in Chile were significant, which became evident in the 1936 census

  17. 15 June 2009 - President of the Argentine Nation C. Fernández visiting ATLAS experimental area.

    CERN Multimedia

    Maximilien Brice

    2009-01-01

    Tirage 1:President of the Argentine Nation, C. Fernández and Minister of Science, Technology and Innovative Production,L. Barañao Tirage 2-8:Arrival greetings Tirage 9-12:Introduction to CERN's activities by Director-General, R. Heuer Tirage 13-15:Signature of the guest book Tirage 16-25:M. Benedetti,R. Heuer and L.Barañao sit for the signature of the Agreement Tirage 26-33: Meeting with Argentinian scientists at CERN

  18. Revisiting Germani: the interpretation of modernity and the theory of action

    Directory of Open Access Journals (Sweden)

    José Maurício Domingues

    2005-01-01

    Full Text Available The work of the Italo-Argentinian sociologist Gino Germani has traditionally been classified as functionalist. However, recent studies have tended to change this perspective, emphasizing other important influences in his work. Against the backdrop of his broader theory, the objective of this article is to analyze, on the one hand, his perception, in the Latin American transition to modernity, of freedom as the essential issue in politics and daily life, and on the other, how this translates into a theory of action that remains overlooked, although only recently equivalents have been found in sociology, with his theory being more advanced in certain aspects than contemporary proposals in this direction.

  19. Sangre de amor correspondido: reflexões sobre um caso de autotradução

    Directory of Open Access Journals (Sweden)

    Andreia dos Santos Menezes

    2008-05-01

    Full Text Available Abstract: In this paper we will discuss about a case of autotranslation by the Argentinian writer Manuel Puig who elaboreteded himself the translation to Spanish of his novel Sangue de amor correspondido which was written in Portuguese. We will talk about the concepts of “retextualização”, model reader and model author, as well as ideal reader and ideal author. We will relate such concepts to the autotranslation for then relate them to the mentioned case of Puig, analyzing some examples of this in his novel.

  20. [Democracy and conflict in pluralist contexts: an interview with Chantal Mouffe].

    Science.gov (United States)

    Mouffe, Chantal; Ramos, Aura Helena; de Oliveira, Anna Luiza A R Martins; de Oliveira, Gustavo Gilson S; de Mesquita, Rui Gomes de Mattos

    2014-01-01

    Chantal Mouffe, along with Argentinian political theorist Ernesto Laclau (1935-2014), laid down the bases of discourse theory in 1985. She later developed her work by exploring in more detail how discourse theory formulations influence the analysis of contemporary democracies. Approaching conflict as a product of the encounter with difference, Mouffe sees it as an indelible part of the constitution of social relationships. In this encounter with the author, we seek to reflect upon certain themes and problematics that are central to her work, and upon the implications of her theory for the field of contemporary education.

  1. The Genetic Diversity of Influenza A Viruses in Wild Birds in Peru.

    Science.gov (United States)

    Nelson, Martha I; Pollett, Simon; Ghersi, Bruno; Silva, Maria; Simons, Mark P; Icochea, Eliana; Gonzalez, Armando E; Segovia, Karen; Kasper, Matthew R; Montgomery, Joel M; Bausch, Daniel G

    2016-01-01

    Our understanding of the global ecology of avian influenza A viruses (AIVs) is impeded by historically low levels of viral surveillance in Latin America. Through sampling and whole-genome sequencing of 31 AIVs from wild birds in Peru, we identified 10 HA subtypes (H1-H4, H6-H7, H10-H13) and 8 NA subtypes (N1-N3, N5-N9). The majority of Peruvian AIVs were closely related to AIVs found in North America. However, unusual reassortants, including a H13 virus containing a PA segment related to extremely divergent Argentinian viruses, suggest that substantial AIV diversity circulates undetected throughout South America.

  2. The promotional value of motorsport culture. A sociological invstigation of the FIA World Rally Championship

    OpenAIRE

    2014-01-01

    From the snow and ice of Scandinavia to the glamour of Monte Carlo, from the heat of Kenya to the thin air in the Argentinian mountainsides, the FIA World Rally Championship (WRC) has served up passionate motorsport drama since its inauguration in its current form in 1973. During that time the sport has transformed from a little-known series to a pop-cultural roadshow worth millions of euros, with 13 rallies scattered around the world and more than 600 million TV-viewers annually. This develo...

  3. El estereotipo invisible: imágenes del afrodescendiente en la narrativa argentina del siglo XIX

    Directory of Open Access Journals (Sweden)

    Javier De Navascués

    2011-12-01

    Full Text Available This paper deals with different images of Black minorities inArgentinian Literature during XIX th. century. At first, Afrodescendants numbered almost 25 % of the population. However, in comparison with other ethnic groups, such as the "gauchos",there are not literary works mainly concerned with Afroargentinian people. They only appear as secondary characters and they are reduced to one or two common places: the loyal servant o the brave soldier, for instance.Ideological motivs could explain this absence. In fact, Black peoplewere exluded from a political agenda created by criollistintellectuals from the historical origins of the Nation.

  4. Datos para una historia de la psicologia experimental Argentina (hasta 1930

    Directory of Open Access Journals (Sweden)

    Mauricio R. Papini

    1976-01-01

    Full Text Available A presentation is made of the early origins of experimental prychology .ín Argentina from 1880 to 1930. During thís 50 year perlod the first chaira of experimental psychology were created in the country. Horacio G. Píñero founded the 6rst experimental psYchology laboratory in 11198,- al the Colegio Nacional of Buenos Aires. During tbis period ltriiger. Dumas. Janet and Kohler visited Argentina. After 1980 Argentinian psychology turned to Irratíonalism, and away from experímentatíon.

  5. Historias intramuros

    OpenAIRE

    Torres, Victoria

    2013-01-01

    The articles deals with a series of Argentinian novels published after 2001 that all revolve around the same theme of the gated community. In my reading, I will relate the different texts to actual criminal cases and discuss them in the context of curreng trends in criminal fiction. El artículo analiza novelas argentinas posteriores al 2001 cuyo escenario son los barrios cerrados y las relaciona con los casos policiales reales y con las actuales formas de narrar del género policial.

  6. Argentina`s Claromeco basin needs further exploration

    Energy Technology Data Exchange (ETDEWEB)

    Pucci, J.C. [Energy Secretariat, Buenos Aires (Argentina)]|[Argentina Geological Survey, Buenos Aires (Argentina)

    1995-09-25

    The presence of a sedimentary basin between the Tandilia and Ventana hills south of Buenos Aires was recognized by several workers. The Argentine Secretary of Energy put four blocks in the Claromeco basin out for bids and awarded two to the Argentinian Bridas Co. Bridas committed to the acquisition of 200 km of seismic on each block. This paper reviews the available data on geology, stratigraphy, traps, reservoir seals, and source rocks. Although exploration in the basin would be high risk, the author makes recommendations for a minimum reconnaissance program.

  7. Kikuchi–Fujimoto disease and systemic lupus erythematosus

    Science.gov (United States)

    Baenas, Diego F; Diehl, Fernando A; Haye Salinas, María J; Riva, Verónica; Diller, Ana; Lemos, Pablo A

    2016-01-01

    Kikuchi–Fujimoto disease, or histiocytic necrotizing lymphadenitis, is an infrequent idiopathic disorder. It has been associated with autoimmune disorders, of which systemic lupus erythematosus is the most outstanding. The basis of its diagnosis relies on the histological examination of lymph nodes, which typically reveals necrosis surrounded by histiocytes with crescentic nucleus, immunoblasts and plasma cells, and absence of neutrophils. We report the case of a 27-year-old Argentinian female patient without any relevant past medical history to demonstrate the correlation between Kikuchi–Fujimoto disease and systemic lupus erythematosus. PMID:27418858

  8. Consideraciones biogeográficas y ecológicas de equinodermos arquibentónicos de Chile Central (com excepción de crinoidea

    Directory of Open Access Journals (Sweden)

    Héctor Andrade Vasquez

    1980-12-01

    Full Text Available 30 echinoderm species (the crinoias excepted have been recorded from the archibenthos off Central Chile. Samples were taken at 5 stations (from Los Vilos to Quíntero. 250-450 m depth range, every 15 days for one year. The concept of Region or Province, usually related to the intertital fauna from high latitudes are showed to be impractical using them with archibenthal echinoderms. The presence oj some species that had been registered as characteristic from the Antarctic Region and/or present in the Argentinian and Magellanic Province is related with the Antarctic Intermediate Water Mass, which is at the capture depth in the sampled area.

  9. Post-Colony/Post-Dictatorship

    Directory of Open Access Journals (Sweden)

    Juan Obarrio

    2013-12-01

    Full Text Available This essay focuses on two questions. On a general level: the relevance of postcolonial studies, after Twentieth century's second half, in the historical processes and the political cultures of the global South - concentrating on the exploration of the Argentinian position related to its Latin American regional context. More specifically, the article stresses the comparative perspective's importance to analyze the tension between postcolony/postdictatorship and the democratic transition. These questions are read within contemporary violent processes of primitive accumulation of capital, with its specific death's technologies.

  10. Feminist Yönetmen Bemberg’de Anne-Kız İlişkisi

    OpenAIRE

    Derya Nacaroglu

    2010-01-01

    In this study an Argentinian Feminist director Maria Lusia Bemberg‟s film I Don’t Want to Talk About it (1993) is analyzed. The specific focus is on how women are evaluated within the framework of a mother-daughter relationship. It is argued that Bemberg presents a feminist treatment of how a woman responds to the pressure present in a patriarchal family system. As a result, the mother‟s struggle to show her disabled daughter to society like a “normal” person illustrates the pressure and prob...

  11. Feminist Yönetmen Bemberg’de Anne-Kız İlişkisi

    Directory of Open Access Journals (Sweden)

    Derya Nacaroglu

    2010-09-01

    Full Text Available In this study an Argentinian Feminist director Maria Lusia Bemberg‟s film I Don’t Want to Talk About it (1993 is analyzed. The specific focus is on how women are evaluated within the framework of a mother-daughter relationship. It is argued that Bemberg presents a feminist treatment of how a woman responds to the pressure present in a patriarchal family system. As a result, the mother‟s struggle to show her disabled daughter to society like a “normal” person illustrates the pressure and problem created by a daughter‟s independence.

  12. QUBIC Experiment

    CERN Document Server

    Stolpovskiy, Mikhail

    2016-01-01

    QUBIC is a ground-based experiment, currently under construction, that uses the novel bolometric interferometry technology. It is dedicated to measure the primordial B-modes of CMB. As a bolometric interferometer, QUBIC has high sensitivity and good systematics control. Dust contamination is controlled by operating with two bands -- 150 and 220 GHz. There are two possible sites for QUBIC: either Concordia station in Antarctic or in the Argentinian Puna desert. It is planned to see the first light in 2018-2019.

  13. Problems of implementing a large contract abroad: the Cordoba nuclear power station

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, P.

    1984-11-01

    The building of Argentina's second nuclear power station proved to be a true test of project-management skills: the contract was to be a joint effort between an Italian and a Canadian company, to be implemented in a country thousands of miles away; the Argentinian government changed four times during the course of the project; and the local currency was always unstable and unpredictable. The various difficulties that arose, and how they were solved, are described, and the role of the project management is evaluated.

  14. Problems of implementing a large contract abroad: the Cordoba nuclear power station

    International Nuclear Information System (INIS)

    The building of Argentina's second nuclear power station proved to be a true test of project-management skills: the contract was to be a joint effort between an Italian and a Canadian company, to be implemented in a country thousands of miles away; the Argentinian government changed four times during the course of the project; and the local currency was always unstable and unpredictable. The various difficulties that arose, and how they were solved, are described, and the role of the project management is evaluated. (author)

  15. Las armas de la conquista. Presencia de armas de fuego en sitios coloniales de Argentina

    Directory of Open Access Journals (Sweden)

    Ana Igareta

    2013-12-01

    Full Text Available Objects used as weapons by the man had interested archaeologists worldwide since the early times of the discipline. Cultural sequences had been defined using the evolution arms as one of the relevant material indicators of social development. Argentinian archaeology has an extensive tradition of prehistoric weapons studies, but little attention has been accorded to the repertoire of arms -particulary firearmsused during colonial confrontations between Spanish soldiers and native population. The current paper briefly summarizes the main findings of colonial firearms remains in Argentina as well as reviews potential difficulties during archaeological identification of those remains.

  16. Rappresentazioni e (intraducibilità del delirio: Informe sobre ciegos di Alberto Breccia

    Directory of Open Access Journals (Sweden)

    Susanna Nanni

    2015-07-01

    Full Text Available The essay proposes an analysis of the relationship between text and images in Informe sobre ciegos (1991 by Alberto Breccia. In his obstinate renunciation to unnecessary words, or surplus signs, and by employing graphic devices that convey a "telluric and formless" world, Breccia interprets and illustrates – without making it comprehensible – the self-destructive delirious state of Fernando Vidal, one of the most controversial and fascinating characters in Argentinian literature. In particular, the essay focuses on the conspiracy – at the level of both form and content – and on the graphic (untranslatability of his delirium.

  17. CAPITAL INTELECTUAL Y COMPETENCIAS DISTINTIVAS EN PYMES MADERERAS DE ARGENTINA

    Directory of Open Access Journals (Sweden)

    Carlos M. F-Jardon

    2014-10-01

    Full Text Available In the knowledge economy, intellectual capital is increasingly becoming important as a source of core competences. A core competence is obtained by combining internal and external factors of the company by means of the strategy to generate better performance than its competitors. The Argentinian wood SMEs often have specific characteristics and, in particular, a limited intellectual capital. Consequently, it is expected that the process of establishing core competences is different. This paper analyzes the characteristics of that process. The results show how they organize their resources and capabilities to provide their competitiveness. This competitiveness leads to better organizational performance, but does not directly affect economic performance.

  18. Why are some mitochondria more powerful than others: insights from comparisons of muscle mitochondria from three terrestrial vertebrates.

    Science.gov (United States)

    Guderley, Helga; Turner, Nigel; Else, Paul L; Hulbert, A J

    2005-10-01

    We studied the molecular composition of muscle mitochondria to evaluate whether the contents of cytochromes or adenine nucleotide translocase (ANT) or phospholipid acyl compositions reflect differences in mitochondrial oxidative capacities. We isolated mitochondria from three vertebrates of similar size and preferred temperature, the rat (Rattus norvegicus), the cane toad (Bufo marinus) and the bearded dragon lizard (Pogona vitticeps). Mitochondrial oxidative capacities were higher in rats and cane toads than in bearded dragon, whether rates were expressed relative to protein, cytochromes or ANT. Inter-specific differences were least pronounced when rates were expressed relative to cytochrome A, a component of cytochrome C oxidase (CCO), or ANT. In mitochondria from rat and cane toad, cytochrome A was more abundant than C followed by B and then C(1), while in bearded dragon mitochondria, the cytochromes were present in roughly equal levels. Analysis of correlations between mitochondrial oxidative capacities and macromolecular components revealed that cytochrome A explained at least half of the intra- and inter-specific variability in substrate oxidation rates. ANT levels were an excellent correlate of state 3 rates while phospholipid contents were correlated with state 4 rates. As the % poly-unsaturation and the % 20:4n-6 in mitochondrial phospholipids were equivalent in toads and rats, and exceeded the levels in lizards, they may contribute to the inter-specific differences in oxidative capacities. We suggest that the numbers of CCO and ANT together with the poly-unsaturation of phospholipids explain the higher oxidative capacities in muscle mitochondria from rats and cane toads. PMID:16085440

  19. Optimisation of an oviposition protocol employing human chorionic and pregnant mare serum gonadotropins in the Barred Frog Mixophyes fasciolatus (Myobatrachidae

    Directory of Open Access Journals (Sweden)

    Clulow John

    2012-08-01

    Full Text Available Abstract Background Protocols for the hormonal induction of ovulation and oviposition are essential tools for managing threatened amphibians with assisted reproduction, but responses vary greatly between species and even broad taxon groups. Consequently, it is necessary to assess effectiveness of such protocols in representative species when new taxa become targets for induction. The threatened genus Mixophyes (family Myobatrachidae has amongst the highest proportion of endangered species of all the Australian amphibians. This study developed and optimised the induction of oviposition in a non-threatened member of this taxon, the great barred frog (Mixophyes fasciolatus. Methods Gravid female M. fasciolatus were induced to oviposit on one or more occasions by administration of human chorionic gonadotropin (hCG with or without priming with pregnant mare serum gonadotropin (PMSG. Treatments involved variations in hormone doses and combinations (administered via injection into the dorsal lymph sacs, and timing of administration. Pituitary homogenates from an unrelated bufonid species (Rhinella marina were also examined with hCG. Results When injected alone, hCG (900 to 1400 IU induced oviposition. However, priming with two time dependent doses of PMSG (50 IU, 25 IU increased responses, with lower doses of hCG (200 IU. Priming increased response rates in females from around 30% (hCG alone to more than 50% (p = 0.035, and up to 67%. Increasing the interval between the first PMSG dose and first hCG dose from 3 to 6 days also produced significant improvement (p Conclusions This study found that M. fasciolatus is amongst the few amphibian species (including Xenopus (Silurana and some bufonids that respond well to the induction of ovulation utilising mammalian gonadotropins (hCG. The optimal protocol for M. fasciolatus involved two priming doses of PMSG (50 IU and 25 IU administered at 6 and 4 days respectively, prior to two doses of hCG (100 IU, 24

  20. Pulmonary compliance and lung volume varies with ecomorphology in anuran amphibians: implications for ventilatory-assisted lymph flux.

    Science.gov (United States)

    Hedrick, Michael S; Hillman, Stanley S; Drewes, Robert C; Withers, Philip C

    2011-10-01

    Vertical movement of lymph from ventral regions to the dorsally located lymph hearts in anurans is accomplished by specialized skeletal muscles working in concert with lung ventilation. We hypothesize that more terrestrial species with greater lymph mobilization capacities and higher lymph flux rates will have larger lung volumes and higher pulmonary compliance than more semi-aquatic or aquatic species. We measured in situ mean and maximal compliance (Δvolume/Δpressure), distensibility (%Δvolume/Δpressure) and lung volume over a range of physiological pressures (1.0 to 4.0 cmH(2)O) for nine species of anurans representing three families (Bufonide, Ranidae and Pipidae) that span a range of body masses and habitats from terrestrial to aquatic. We further examined the relationship between these pulmonary variables and lymph flux for a semi-terrestrial bufonid (Rhinella marina), a semi-aquatic ranid (Lithobates catesbeianus) and an aquatic pipid (Xenopus laevis). Allometric scaling of pulmonary compliance and lung volume with body mass showed significant differences at the family level, with scaling exponents ranging from ∼0.75 in Bufonidae to ∼1.3 in Pipidae. Consistent with our hypothesis, the terrestrial Bufonidae species had significantly greater pulmonary compliance and greater lung volumes compared with semi-aquatic Ranidae and aquatic Pipidae species. Pulmonary distensibility ranged from ∼20 to 35% cmH(2)O(-1) for the three families but did not correlate with ecomorphology. For the three species for which lymph flux data are available, R. marina had a significantly higher (P<0.001) maximal compliance (84.9±2.7 ml cmH(2)O(-1) kg(-1)) and lung volume (242.1±5.5 ml kg(-1)) compared with L. catesbeianus (54.5±0.12 ml cmH(2)O(-1) kg(-1) and 139.3±0.5 ml kg(-1)) and X. laevis (30.8±0.7 ml cmH(2)O(-1) kg(-1) and 61.3±2.5 ml kg(-1)). Lymph flux rates were also highest for R. marina, lowest for X. laevis and intermediate in L. catesbeianus. Thus, there is

  1. La construcción de la subjetividad. El impacto de las políticas sociales

    Directory of Open Access Journals (Sweden)

    Nora Mabel Briuoli

    2009-12-01

    Full Text Available El objetivo de este trabajo es abordar el modo complejo en que la realidad social impacta en la construcción de la subjetividad. Los ejes de análisis son los siguientes: La Construcción De La Subjetividad. Las funciones simbólicas que permiten dicho proceso psíquico. Los Nuevos Sujetos y Territorios de la precariedad y la desafiliación. Los Lazos Sociales. Nuevos roles. Declive de las instituciones y de los dispositivos de la Ley. Viejas Problemáticas planteadas Como Nuevas en el contexto actual: Desocupación, robo, adicciones, problemáticas escolares, los hijos de desaparecidos. Lo complejo de la realidad a la que nos enfrentamos en la vida cotidiana. Necesidad de revisar nuestras miradas e intervenciones.___________________ABSTRACT:The research has the purpose of analyzing the influence of the Army institutions during the return to the argentinian democratic system in 1983. It tries to study the way in which the Army influenced in the speeches of the electoral campaign, the political decisions put in practice by the Alfonsin Administration in military order, the Argentinian Forces imbalances, the disposition (or not of subordinating to the civil power and their role during the mutinies between 1987 and 1989, ideas that will allow an adequate analysis of the abilities and fragilities of the government strategies in the military sphere.

  2. Fuerzas Armadas y transición democrática. Argentina, 1983-1989

    Directory of Open Access Journals (Sweden)

    Andrés Alberto Masi Rius

    2009-12-01

    Full Text Available El presente trabajo procura analizar el grado de influencia que las instituciones militares tuvieron en la apertura democrática argentina en 1983. Se analizará la modalidad en que las Fuerzas Armadas influyeron en los discursos en la campaña electoral, las medidas implementadas por la Administración Alfonsín en materia militar, los desequilibrios internos del Ejército Argentino, la disposición (o no de las Fuerzas de subordinarse al poder civil y el rol que las mismas desempeñaron en los levantamientos de 1987 y 1989, líneas que permitirán una adecuado análisis de los aciertos y fragilidades de las estrategias de gobierno en la esfera castrense.______________________ABSTRACT:The research has the purpose of analyzing the influence of the Army institutions during the return to the argentinian democratic system in 1983. It tries to study the way in which the Army influenced in the speeches of the electoral campaign, the political decisions put in practice by the Alfonsin Administration in military order, the Argentinian Forces imbalances, the disposition (or not of subordinating to the civil power and their role during the mutinies between 1987 and 1989, ideas that will allow an adequate analysis of the abilities and fragilities of the government strategies in the military sphere.

  3. O galego como lingua de contacto co castelán riopratense: unha relación esquecida

    Directory of Open Access Journals (Sweden)

    Carsten Sinner

    2016-01-01

    Full Text Available Unlike contact between Spanish and other languages such as Catalan, contact between Galician and Spanish, two closely related Ibero-Romance languages, has hardly been studied at all. Studies of contact between Galician and American Spanish are rarer still. While contact between Spanish and immigrant languages such as Italian, French, German or even Danish in the Rio de la Plata area and Argentina in particular has been the topic of numerous studies, Spanish-Galician contact is generally ignored. The main focus of the present article is the curious fact that the Galician language has never attracted the attention of Argentinian linguists and scholars in Hispanic Linguistics, not even in the area within the latter dedicated specifically to Argentina’s national language. This fact seems to be related to gen- eral cultural prejudice against Galicians in the Rio de la Plata area. Examples are presented of the influence of Galician on Argentinian Spanish. The article is based on a detailed study of the existing linguistic literature and a number of recent empirical studies in the framework of a research project on language contact among Ibero- -Romance Languages in the Department for Applied Linguistics and Translation Studies at Leipzig University.

  4. Advertisement call of species of the genus Frostius Cannatella 1986 (Anura: Bufonidae

    Directory of Open Access Journals (Sweden)

    Flora A. Juncá

    2012-12-01

    Full Text Available Frostius pernambucensis and F. erythrophthalmus are cryptic bufonid species recognized mainly by the iris color: yellow in F. permambucensis and red in F. erythrophthalmus. However, field studies showed that the iris color of F. erythrophthalmus could vary between yellow and red. To improve the recognition of these species we described the advertisement call of Frostius pernambucensis and Frostius erythrophthalmus and we tested if call characteristics are influenced by temperature, male size and perch height. We also report on a physical interaction between two males of F. pernambucensis and the associated vocalization, suggesting that F. pernambucensis has not a territorial call or encounter call. Comparing the advertisement calls, the call of F. pernambucensis was lower, shorter and with a smaller number of notes than the call of F. erythrophthalmus. Dominant frequency and fundamental frequency variation of the F. pernambucensis advertisement call were related to the male’s size, while the call emission rate was related to air temperature. However, we could not find relationship among the acoustic characteristic of F. erythrophthalmus and male size or temperature.

  5. The structure of zetekitoxin AB, a saxitoxin analog from the Panamanian golden frog Atelopus zeteki: a potent sodium-channel blocker.

    Science.gov (United States)

    Yotsu-Yamashita, Mari; Kim, Yong H; Dudley, Samuel C; Choudhary, Gaurav; Pfahnl, Arnold; Oshima, Yasukatsu; Daly, John W

    2004-03-30

    Bufonid anurans of the genus Atelopus contain both steroidal bufadienolides and various guanidinium alkaloids of the tetrodotoxin class. The former inhibit sodium-potassium ATPases, whereas the latter block voltage-dependent sodium channels. The structure of one guanidinium alkaloid, zetekitoxin AB, has remained a mystery for over 30 years. The structure of this alkaloid now has been investigated with a sample of approximately 0.3 mg, purified from extracts obtained decades ago from the Panamanian golden frog Atelopus zeteki. Detailed NMR and mass spectral analyses have provided the structure and relative stereochemistry of zetekitoxin AB and have revealed that it is an analog of saxitoxin. The proposed structure is characterized by richness of heteroatoms (C16H25N8O12S) and contains a unique 1,2-oxazolidine ring-fused lactam, a sulfate ester, and an N-hydroxycarbamate moiety. Zetekitoxin AB proved to be an extremely potent blocker of voltage-dependent sodium channels expressed in Xenopus oocytes. The IC50 values were 280 pM for human heart channels, 6.1 pM for rat brain IIa channels, and 65 pM for rat skeletal muscle channels, thus being roughly 580-, 160-, and 63-fold more potent at these channels than saxitoxin. PMID:15070720

  6. Effects of Roads on Amphibian Populations

    DEFF Research Database (Denmark)

    Hels, T.

    to have experienced the wonders of early summer sunrises in the field - and the joy of thawing out frozen fingers after hours of field work around freezing point. Amphibian populations are declining. This worrying fact is what has initiated this work. Some fifty years ago, the life history of frogs...... and toads was common knowledge to everybody due to personal experience: amphibians were abundant. Noisy and innumerable in spring when reproducing, silent and even more abundant in late summer with both adults and metamorphs leaving the breeding ponds. Today, experiencing frogs and toads is an event......, something to talk about. Fortunately, amphibians are still numerous in certain places and hopefully, we will get to a point when we know enough about the declines and their backgrounds to bring the decline to an end. It is my hope that results of this work will add a piece to the puzzle. This work...

  7. Evolution of dispersal and life history interact to drive accelerating spread of an invasive species.

    Science.gov (United States)

    Perkins, T Alex; Phillips, Benjamin L; Baskett, Marissa L; Hastings, Alan

    2013-08-01

    Populations on the edge of an expanding range are subject to unique evolutionary pressures acting on their life-history and dispersal traits. Empirical evidence and theory suggest that traits there can evolve rapidly enough to interact with ecological dynamics, potentially giving rise to accelerating spread. Nevertheless, which of several evolutionary mechanisms drive this interaction between evolution and spread remains an open question. We propose an integrated theoretical framework for partitioning the contributions of different evolutionary mechanisms to accelerating spread, and we apply this model to invasive cane toads in northern Australia. In doing so, we identify a previously unrecognised evolutionary process that involves an interaction between life-history and dispersal evolution during range shift. In roughly equal parts, life-history evolution, dispersal evolution and their interaction led to a doubling of distance spread by cane toads in our model, highlighting the potential importance of multiple evolutionary processes in the dynamics of range expansion.

  8. Choosy Cannibals Preferentially Consume Siblings with Relatively Low Fitness Prospects.

    Science.gov (United States)

    Dugas, Matthew B; McCormack, Larkin; Gadau, Alice; Martin, Ryan A

    2016-07-01

    When an individual can selfishly cannibalize a relative or altruistically set it free, the benefits of altruism will be positively associated with the relative's fitness prospects (the benefits it receives from altruism). We tested the prediction that altruism should be preferentially directed toward high-quality relatives using larvae of the New Mexican spadefoot toad (Spea multiplicata), a species in which tadpoles plastically express omnivore and carnivore ecomorphs. In a no-choice design, we presented carnivores with sibling or nonsibling omnivores varying in developmental stage, which is positively associated with survival in this toad's ephemeral larval environment. There was a significant interaction between relatedness and developmental stage on the probability of cannibalism: carnivores were overall more likely to cannibalize less developed omnivores, but this effect was exaggerated when the potential victim was a sibling. This evidence that altruists favor relatives with high fitness prospects highlights the numerous factors shaping altruism's payoffs. PMID:27322127

  9. Amphibian monitoring in the Atchafalaya Basin

    Science.gov (United States)

    Waddle, Hardin

    2011-01-01

    Amphibians are a diverse group of animals that includes frogs, toads, and salamanders. They are adapted to living in a variety of habitats, but most require water for at least one life stage. Amphibians have recently become a worldwide conservation concern because of declines and extinctions even in remote protected areas previously thought to be safe from the pressures of habitat loss and degradation. Amphibians are an important part of ecosystem dynamics because they can be quite abundant and serve both as a predator of smaller organisms and as prey to a suite of vertebrate predators. Their permeable skin and aquatic life history also make them useful as indicators of ecosystem health. Since 2002, the U.S. Geological Survey has been studying the frog and toad species inhabiting the Atchafalaya Basin to monitor for population declines and to better understand how the species are potentially affected by disease, environmental contaminants, and climate change.

  10. Cryptosporidia: epicellular parasites embraced by the host cell membrane.

    Science.gov (United States)

    Valigurová, Andrea; Jirků, Miloslav; Koudela, Bretislav; Gelnar, Milan; Modrý, David; Slapeta, Jan

    2008-07-01

    The ultrastructure of two gastric cryptosporidia, Cryptosporidium muris from experimentally infected rodents (Mastomys natalensis) and Cryptosporidium sp. 'toad' from naturally infected toads (Duttaphrynus melanostictus), was studied using electron microscopy. Observations presented herein allowed us to map ultrastructural aspects of the cryptosporidian invasion process and the origin of a parasitophorous sac. Invading parasites attach to the host cell, followed by gradual envelopment, with the host's cell membrane folds, eventually forming the parasitophorous sac. Cryptosporidian developmental stages remain epicellular during the entire life cycle. The parasite development is illustrated in detail using high resolution field emission scanning electron microscopy. This provides a new insight into the ultrastructural detail of host-parasite interactions and species-specific differences manifested in frequency of detachment of the parasitophorous sac, radial folds of the parasitophorous sac and stem-formation of the parasitised host cell. PMID:18158154

  11. Studies of Annual and Seasonal Variations in Four Species of Reptiles and Amphibians at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Keller, D.C.; Nelson, E.I.; Mullen, M.A.; Foxx, T.S.; Haarmann, T.K.

    1998-07-01

    Baseline studies of reptiles and amphibians of the Pajarito wetlands at Los Alamos National Laboratory have been conducted by the Ecology group since 1990. With the data gathered from 1990-1997 (excluding 1992), we examined the annual and seasonal population changes of four species of reptiles and amphibians over the past seven years. The four species studied are the Woodhouse toad (Bufo woodhousii), the western chorus frog (Pseudacris triseriata), the many-lined skink (Eunzeces nudtivirgatus), and the plateau striped whiptail lizard (Cnemidophorus velox). Statistical analyses indicate a significant change on a seasonal basis for the western chorus frog and the many-lined skink. Results indicate a significant difference in the annual population of the Woodhouse toad.

  12. Studies of annual and seasonal variations in four species of reptiles and amphibians at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, E.I.; Haarmann, T.; Keller, D.C.; Foxx, T.

    1998-11-01

    Baseline studies of reptiles and amphibians of the Pajarito wetlands at Los Alamos National Laboratory have been conducted by the Ecology group since 1990. With the gathered data from 1990--1997 (excluding 1992), they plan to determine if patterns can be found in the annual and seasonal population changes of four species of reptiles and amphibians over the past seven years. The four species studied are the Woodhouse toad, the western chorus frog, the many-linked skink, and the plateau striped whiptail lizard. Statistical analysis results show that significant changes occurred on a seasonal basis for the western chorus frog and the many-lined skink. Results indicate a significant difference in the annual population of the Woodhouse toad.

  13. Decline of electrogenic Na+/K+ pump activity in rod photoreceptors during maintained illumination

    OpenAIRE

    1986-01-01

    Light-evoked changes in membrane voltage were recorded intracellularly from rod photoreceptors in the isolated retina preparation of the toad, Bufo marinus, during superfusion with a solution containing pharmacological agents that blocked voltage-dependent conductances. Under these conditions, the amplitude of the hyperpolarizing photoresponse became much greater than under control conditions. The results of several experiments support the conclusion that this increase in photoresponse amplit...

  14. Widespread disruptive selection in the wild is associated with intense resource competition

    OpenAIRE

    Martin Ryan A; Pfennig David W

    2012-01-01

    Abstract Background Disruptive selection has been documented in a growing number of natural populations. Yet, its prevalence within individual systems remains unclear. Furthermore, few studies have sought to identify the ecological factors that promote disruptive selection in the wild. To address these issues, we surveyed 15 populations of Mexican spadefoot toad tadpoles, Spea multiplicata, and measured the prevalence of disruptive selection acting on resource-use phenotypes. We also evaluate...

  15. Corticotropin-releasing factor (CRF)-like immunoreactivity in the vertebrate endocrine pancreas.

    OpenAIRE

    Petrusz, P; Merchenthaler, I; Maderdrut, J L; Vigh, S; Schally, A V

    1983-01-01

    The light microscopic immunocytochemical localization of corticotropin-releasing factor (CRF) is described in the endocrine pancreas of several species representing the major classes of vertebrates: fishes (channel catfish, Ictalurus punctatus), amphibians (African clawed toad, Xenopus laevis), reptiles (chameleon, Anolis carolinensis), birds (chicken, Gallus domesticus), and several mammals (rat, mouse, cat, rhesus monkey, and man). The CRF-containing cells are scattered over the entire isle...

  16. Clutch size in wild populations of Alytes muletensis

    OpenAIRE

    Samuel Pinya; Valentín Pérez-Mellado

    2014-01-01

    Clutch size of genus Alytes presents strong inter- and intra-specific variability. The Mallorcan midwife toad (A. muletensis) is a threatened endemism of the island of Mallorca (Spain), and has the smallest clutch size of the genus. Most of the previously published clutch size information was obtained from animals breeding in captivity. In this study we analysed a large number of clutches from wild populations, and we compared their size (number of eggs) with previously published data from bo...

  17. Bent's Old Fort: Amphibians and Reptiles

    Science.gov (United States)

    Muths, E.

    2008-01-01

    Bent's Old Fort National Historic Site sits along the Arkansas River in the semi-desert prairie of southeastern Colorado. The USGS provided assistance in designing surveys to assess the variety of herpetofauna (amphibians and reptiles) resident at this site. This brochure is the results of those efforts and provides visitors with information on what frogs, toads, snakes and salamanders might be seen and heard at Bent's Old Fort.

  18. Venomous and Poisonous Australian Animals of Veterinary Importance: A Rich Source of Novel Therapeutics

    OpenAIRE

    Hardy, Margaret C.; Jonathon Cochrane; Allavena, Rachel E.

    2014-01-01

    Envenomation and poisoning by terrestrial animals (both vertebrate and invertebrate) are a significant economic problem and health risk for domestic animals in Australia. Australian snakes are some of the most venomous animals in the world and bees, wasps, ants, paralysis ticks, and cane toads are also present as part of the venomous and poisonous fauna. The diagnosis and treatment of envenomation or poisoning in animals is a challenge and can be a traumatic and expensive process for owners. ...

  19. Injuries, envenomations and stings from exotic pets

    OpenAIRE

    Warwick, Clifford; Steedman, Catrina

    2012-01-01

    A variety of exotic vertebrate and invertebrate species are kept as ‘pets’ including fishes, amphibians (for example, frogs and toads), reptiles (turtles, crocodiles, lizards and snakes), birds, mammals (for example, primates, civets, and lions), and invertebrates (for example spiders, scorpions, and centipedes), and ownership of some of these animals is rising. Data for 2009–2011 suggest that the number of homes with reptiles rose by approximately 12.5%. Recent surveys, including only some o...

  20. Historical biogeography of Western Palearctic pelobatid and pelodytid frogs: a molecular phylogenetic perspective

    OpenAIRE

    Veith, M.; Fromhage, L.; Kosuch, J.; Vences, M.

    2006-01-01

    Abstract Spadefoot toads (Pelobates) and Parsley frogs (Pelodytes) are an enigmatic group of Western Palaearctic anurans. In the genus Pelobates, a fossorial lifestyle has enforced a conserved bauplan that masks their intraspecific evolutionary history. We used partial sequences of the mitochondrial 16S and 12S rRNA genes to infer a paleobiogeographic scenario of speciation events in these two anuran genera. Based on two alternative, mutually exclusive calibrations of the Iberian-African spli...