338 research outputs found

    Palinología e importancia paleoambiental de la Formación Tunal (Daniano) en su localidad tipo, Quebrada el Chorro (Salta, Argentina).

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    The palynologic investigation of samples from the Tunal Formation at El Chorro creek (Salta, Argentina) resulted in the recovery of terrestrial assemblages of pollen and spores associated with freshwater algae (Pediastrum spp. and Scenedesmus sp.). Of the 43 species of sporomorphs identified for the Tunal Formation so far, 28 species are cited here for the first time. The spores and pollen indicate a Danian age at the type locality. Sedimentary proxidata including abundant evaporites suggest intervals of at least seasonal arid environmental conditions. In contrast, the palynologic assemblages recovered from the organic rich dark shales indicate the presence of swampy areas and forests surrounding them. The dominance of Verrustephanoporites simplex Leidelmeyer (corresponding to the modern Phyllostylon, Ulmaceae) indicates abundant seasonal rainfalls, warm humid conditions and subtropical climate.La investigación palinológica de muestras extraídas de la Formación Tunal en la quebrada El Chorro (Salta, Argentina) resultó en la recuperación de una asociación de polen y esporas, juntamente con algas de agua dulce (Pediastrum spp. y Scenedesmus sp.). De las 43 especies de esporomorfos identificadas hasta el momento para la Formación Tunal, 28 se citan aquí por primera vez. Las esporas y polen indican edad Daniana en la localidad tipo. Los proxidata sedimentarios incluyendo abundantes evaporitas, sugieren intervalos al menos estacionales de condiciones ambientales áridas. Por otro lado, las asociaciones palinológicas recuperadas de las pelitas oscuras ricas en materia orgánica indican la presencia de áreas anegadas y selvas en sus alrededores. En las últimas, el predominio de Verrustephanoporites simplex Leidelmeyer (que se corresponde con el actual Phyllostylon, Ulmaceae) indica abundantes lluvias estacionales, condiciones cálido-húmedas y clima subtropicalFil: Volkheimer, Wolfang. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Novara, Martin Guillermo. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; ArgentinaFil: Narvaez, Paula Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Marquillas, Rosa Argentina. Universidad Nacional de Salta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta; Argentin

    Jurassic conchostracans from Patagonia

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    24 p., 19 fig.http://paleo.ku.edu/contributions.htm

    A Danian subtropical lacustrine palynobiota from South America (Bororó Formation, San Jorge Basin, Patagonia - Argentina)

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    New results on a lacustrine Danian palynological association in extra-andean northern Patagonia (lower member of the Cerro Bororó Formation, San Jorge Basin, Chubut province, Argentina) are presented. This is a contribution to the largely unexplored field of Paleogene freshwater environments. The palynobiota includes representatives of the kingdoms Protoctista and Plantae. Twelve of the aquatic species are Protoctista. From the nine Chlorophyta form-species, four correspond to Botryococcaceae, one to Coelastraceae and four to Zygnemataceae (Gelasinicysta, Schizosporis, Ovoidites, and Pseudoschizaea). The remaining forms are dinoflagellate cysts (Peridinium and dinocyst indet.) and prasinophyceans (Leiosphaeridia). Plants are represented by spores and pollen of Bryophytes (Sphagnaceae and Ricciaceae), Pteridophytes (Salviniaceae), and Angiosperms (Arecaceae, Araceae and Sparganiaceae/Typhaceae, the latter representing macrophytes living in or near the swampy areas). Other palynomorph groups closely related with biotopes of permanent moisture are dominated by spores of the families Selaginellaceae, Lycopodiaceae, Cyatheaceae, Schizaeaceae, Polypodiaceae and Psilotaceae. The palynological assemblage reflects a freshwater lacustrine environment that developed in a marine coastal zone nearby brackish coastal swamps. Based on the composition of the palynoflora including palm pollen and other thermophilous taxa, humid, warm climatic conditions are inferred for the area of deposition

    Predictors of Mental Health Help-Seeking in Alaska Native Communities

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    American Indian/Alaska Native (AI/AN) persons have been identified as a group with greater risk for transgenerational trauma; furthermore, they experience environmental, systemic, and pragmatic barriers to treatment for mental and social issues. Researchers have called for more studies of groups like AI/AN to better understand the complex social, interpersonal, and intrapersonal problems involved in accessing and using mental health services. The purpose of this study was to examine the predictive relationships of demographics, transgenerational trauma, locus of control, and stigma on help-seeking and use of mental health services in the AI/AN population in a quantitative study. The developmentally based trauma framework was chosen as the conceptual framework and theory of planned behavior was chosen as the theoretical framework for this study. A correlational survey research design using a quota sampling strategy was employed. The predictors included demographics, transgenerational trauma, stigma, and locus of control. The criterion variables included attitude towards help-seeking, intention to seek help, and use of mental health services. A hierarchical multiple linear regression analysis plan was implemented. Findings were nonsignificant for all predictors except the measure of transgenerational trauma. Limitations regarding the challenges of working with the AI/AN population and conducting survey research during extraordinary external circumstances (the Covid 19 pandemic) are discussed. Although the findings were non-significant, the results point to research methods that are innovative and culturally relevant to support better response rates and integrate with positive social change for vulnerable populations like AI/AN

    Environmental and climatic proxies for the Cañadón Asfalto and Neuquén basins (Patagonia, Argentina): review of middle to upper jurassic continental and near coastal sequences

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    In this review, we include several proxies (sedimentology, palynology, invertebrates) from the Cañadón Asfalto and Neuquén basins, to infer the environments and regional climatic context during the Middle to Late Jurassic of Patagonia. In central Patagonia, early in the Middle Jurassic, and associated with a magmatic arc, began the sedimentary fi lling of Jurassic continental sub-basins in the Cañadón Asfalto Basin. Lacustrine and fl uvio-deltaic sediments, bearing a continental Middle Jurassic palynobiota, correspond to the Las Chacritas Member, while the sediments and palynobiota from the Late Jurassic Puesto Almada Member (both in the Cañadón Asfalto Formation) indicate a palustrine wetland subenvironment immersed within an arid macroenvironment. Paleoinvertebrates (conchostracans and sponges) of this formation suggest wet-dry cycles in the water bodies they inhabited. The sedimentological information together with the continental and coastal palynomorph assemblages of the back arc Neuquén Basin, allowed distinguishing a complete regressive-transgressive sequence for the Middle Jurassic Lajas Formation. For the Upper Jurassic in this basin, the thick gypsum and anhydrite deposits of the evaporitic coastal Auquilco Formation correlate with extended deposits of eolian sandstones corresponding to the Botucatú paleodesert, and a saltmarsh environment is inferred from the palynofl ora. The palynologic associations from both basins indicate a regional warm climate with seasonal aridity. Climatic conditions would have been drier in the continental interior (Cañadón Asfalto Basin), with strongly seasonally distributed temperatures, and moister in the western coast of the continent (Neuquén Basin), during the marine transgressions.Na presente revisão foram incluídos vários proxies (sedimentologia, palinologia, invertebrados), das bacias de Cañadón Asfalto e Neuquén, para inferir o contexto climático regional e ambiental durante o Jurássico Médio e Superior da Patagônia. Na região central da Patagônia, no início do Jurássico Médio, e associado a um arco magmático, começou o preenchimento sedimentar de sub-bacias continentais jurássicas na bacia Cañadón Asfalto. Os sedimentos flúvio-deitaico e lacustres, tendo uma palinobiota continental do Jurássico Médio correspondente ao Membro Las Chacritas, enquanto os sedimentos e a palinobiota do Jurássico Superior do Membro Puesto Almada (ambos na Formação Cañadón Asfalto) indicam um subambiente palustre úmido imerso em um macroambiente árido. Os paleoinvertebrados (conchostráceos e esponjas) desta formação sugerem ciclos úmidos-secos nos corpos de água por eles habitados. A informação sedimentológica juntamente com as assembleias de palinomorfos continentais e costeiros do “back arc” da bacia Neuquén permitiu distinguir uma sequência completa regressiva-transgressiva para o Jurássico Médio da Formação Lajas. Para o Jurássico Superior, os depósitos de anidrita e gesso espessos da Formação Auquilco costeira evaporítica correlacionam-se com depósitos extensos de arenitos eólicos correspondentes ao paleodeserto Botucatu. Um ambiente “saltmarsh” é inferido a partir da palinoflora. As associações palinológicas de ambas as bacias indicam um clima regional quente com aridez sazonal. As condições climáticas teriam sido mais secas no interior continental (bacia Cañadón Asfalto), com temperaturas fortemente distribuídas de forma sazonal, e úmidas na costa ocidental do continente (bacia de Neuquén), durante as transgressões marinhas.Fil: Volkheimer, Wolfang. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Quattrocchio, Mirta Elena. Universidad Nacional del Sur. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cabaleri, Nora Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geocronología y Geología Isotopica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geocronología y Geología Isotópica; ArgentinaFil: Narvaez, Paula Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Rosenfeld, U.. Westfälische Wilhelms-universität Münster; AlemaniaFil: Scafati, Laura Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Melendi, Daniel Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentin

    Datos palinologicos del Bayociano (formación Cura Niyeu) de la Sierra de Chacai Cô, Cuenca Neuquina, Argentina

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    "Palynological data from the Bayocian Cura Niyeu Fm. of Sierra de Chacai Co, Neuqudn Basin, Argentina". - In marine strata with Sonninia ssp. and Otoites spp., 5 microfloristic assemblages have been identified. More than 60 terrestrial and 8 marine species of palynomorphs belong to the following genera: Alisporites, Anapiculatispohtes, Antulsporites, Araucariacites, Baculatisporites, Biretisporites, Callialasporites, Cerebropollenites, Classopollis, Concavisporites, Converrucosisporites, Cycadopites, Deltoidospora, Dictyophyllidites, Duplexisporites, Equisetosporites, Gleicheniidites, Inapertisporites, Interulobites, Ischyosporites, Leptolepidites, Lycopodiumsporites, Marattisporites, Microcachryidites, Monosulcties, Nevesisporites, Perinopollenites, Peromonolites, Phrixipollenites, Podocarpidites, Staplinisporites, Stereisporites, Taurocusporites, Todisporites, Trisaccites, Uvaesporites, Verrucosisporites, Vitreisporites, Baltisphaeridium, Campenia, Cymatiosphaera, Leiosphaeridia, Lancettopsis, Micrhystridium, Pleurozonaria, Veryhachium. The microflora is compared with other palynomorph assemblages from the Middle and Upper Jurassic of the Neuquen Basin and other regions

    Estudio palinologico de la Formacion Piedra Pintada, Jurasico inferior da la Cuenca Neuquina (Argentina)

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    This is a study of four microfloristic assemblages, in which the terrestrial species (43) are prevailing. The genera present are Deltoidospora, Alsophilidites, Dictyophyllidites, Lygodiumsporites, Concavisporites, Verrucosisporites, Leptolepidites, Foveosporites, Granulat isporit es, Baculatisporites, Lycopodiumsporites, Gleicheniidites, Antulsporites, Interulobites, Nevesisporites, Taurocusporites, Peromonolites, Vitreisporites, Alisporites, Podocarpidites, Phrixipollenites, Microcachryidites, Inaperturopollenites, Araucariacites, Perinopollenites, Classopollis, Cycadopites and Monosulcites, and the marine genera Pleurozonaria and Leiosphaeridia. The age indicated by the microflora (Nevesiporites vallatus-Assemblage, previous to the income of Callialasporites spp.), is the pre-upper Toarcian Lower Jurassic

    Lacustrine black shales near to the Paleogene -Neogene boundary in north-western Neuquén Province: palynological evidence

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    Se muestrearon con fines palinológicos sedimentitas lacustres referidas a la Formación Lileo nov. aflorantes en las cercanías de la localidad de Los Miches, en el noroeste de la provincia del Neuquén, República Argentina. Sobre la base del análisis microflorístico las capas portadoras de palinomorfos pueden asignarse al Oligoceno Tardío - Mioceno Temprano. Las rocas muestreadas se caracterizan por lutitas negras, gris verdosas, gris oscuras y castaño claras, alternando con niveles delgados, a veces oolíticos de calizas gris claras, con superficie de meteorización blanco amarillenta. Entre estas sedimentitas se intercalan andesitas, tobas y aglomerados volcánicos de composición mesosilícica. En los afloramientos del área del río Guañacos se observan capas irregulares de carbonato fibroso tanto como baritina nodular con estructura fibroradial, junto con bivalvos indeterminados de agua dulce. La asociación microflorística muestra relativamente baja diversidad. En general, el género Nothofagidites domina la asociación. Los componentes principales de la microflora consisten en granos de polen pertenecientes a varios taxones de angiospermas, tales como Baumannipollis sp. cf. B. variaperturatus, Corsinipollenites atlantica, Milfordia sp., Nothofagidites saraensis, Smilacipites sp. cf. S. echinatus and Tricolpites asperamarginis junto con granos de polen de angiospermas de Araucariacites australis, Equisetosporites notensis y Podocarpidites spp. Los elementos de Pteridophyta/Bryophyta están representados por Cyatheacidites annulatus, Cicatricosisporites sp., Deltoidospora sp., Lycopodiumsporites austroclavatidites, Ricciaesporites sp. y Laevigatosporites ovatus, mientras que entre los taxones lacustres se reconocieron Azolla sp. y Botryococcus sp. (Chlorophyta).Lacustrine sedimentary rocks referred to the Lileo Formation nov. cropping out near Los Miches locality, northwestern Neuquén Province, Argentine Republic, were sampled for palynological study. On the basis of the microfloristic analysis, the palynomorph-bearing beds can be ascribed a Late Oligocene to Early Miocene age. The sampled rocks are black, grey-green, dark grey and light brown shales alternating with thin,locally oolithic, light grey limestones, with yellowish white weathering. Among these rocks are interbedded andesites, tuffs, and volcanic agglomerates of mesosilicic composition. In the outcrops of the Guañacos river area, some irregular beds of fibrous carbonate have been observed as well as fibroradial nodular barite, together with some indeterminate fresh-water. The microfloristic assemblages have a relatively low diversity. In most of them the genus Nothofagidites dominates the association. The components present in the microflora are pollen grains corresponding to several angiosperm taxa, such as Baumannipollis sp. cf. B. variaperturatus, Corsinipollenites atlantica, Milfordia sp., Nothofagidites saraensis, Smilacipites sp. cf. S. echinatus and Tricolpites asperamarginis together with gymnosperm pollen grains of Araucariacites australis, Equisetosporites notensis and Podocarpidites spp. The Pteridophyta/Bryophyta elements are represented by Cyatheacidites annulatus, Cicatricosisporites sp., Deltoidospora sp., Lycopodiumsporites austroclavatidites, Ricciaesporites sp. and Laevigatosporites ovatus, whereas among the lacustrine taxa Azolla sp. and Botryococcus sp. (Chlorophyta) were recognized.Fil: Leanza, Hector Armando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Servicio Geológico Minero Argentino. Delegación General Roca; ArgentinaFil: Volkheimer, Wolfgang. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla | Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Museo de Historia Natural de San Rafael - Ianigla; ArgentinaFil: Hugo, Carlos A.. Servicio Geológico Minero Argentino. Delegación General Roca; ArgentinaFil: Melendi, Daniel Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Rovere, Elizabeth Ivonne. Servicio Geológico Minero Argentino. Delegación General Roca; Argentin

    Molecular phylogeny and diversification history of Prosopis (Fabaceae: Mimosoideae)

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    The genus Prosopis is an important member of arid and semiarid environments around the world. To study Prosopis diversification and evolution, a combined approach including molecular phylogeny, molecular dating, and character optimization analysis was applied. Phylogenetic relationships were inferred from five different molecular markers (matK-trnK, trnL-trnF, trnS-psbC, G3pdh, NIA). Taxon sampling involved a total of 30 Prosopis species that represented all Sections and Series and the complete geographical range of the genus. The results suggest that Prosopis is not a natural group. Molecular dating analysis indicates that the divergence between Section Strombocarpa and Section Algarobia plus Section Monilicarpa occurred in the Oligocene, contrasting with a much recent diversification (Late Miocene) within each of these groups. The diversification of the group formed by species of Series Chilenses, Pallidae, and Ruscifoliae is inferred to have started in the Pliocene, showing a high diversification rate. The moment of diversification within the major lineages of American species of Prosopis is coincident with the spreading of arid areas in the Americas, suggesting a climatic control for diversification of the group. Optimization of habitat parameters suggests an ancient occupation of arid environments by Prosopis species.Fil: Catalano, Santiago Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Vilardi, Juan Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Tosto, Daniela Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Saidman, Beatriz Ofelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentin
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