60 research outputs found

    Devonian palynological assemblages from the San Antonio x-1 Borehole, Tarija Basin, northwestern Argentina

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    The palynological analysis of the 2548-3628 m interval of the San Antonio x-1 Borehole in northwestern Argentina is presented. The illustrated palynoflora is composed of 96 species represented by diverse palynological groups such as trilete spores and cryptospores (46 species), microplankton (39 species), chitinozoans (7 species), scolecodonts, and some remaining specimens in open nomenclature and as incertae sedis. One new species, Retusotriletes ottonei, is described. Thirty-four species are first records in the Argentinean Devonian. Three assemblages (SA1, SA2, and SA3) are defined based on the presence, absence, or abundance of groups of taxa. The presence of Grandispora protea and Grandispora douglastownense among others in the assemblage SA1 is indicative of a late Emsian to mid-Eifelian age. The concurrence of Acinosporites macrospinosus and A. acanthomammillatus in the assemblage SA2 is indicative of a late Eifelian-mid Givetian and is also supported by the appearance of several other species such as Chomotriletes vedugensis, Dibolisporites farraginis and Biharisporites parviornatus. An early Frasnian age is associated to the assemblage SA3 on the basis of the appearances of Lunulidia micropunctata, Pseudolunulidia laevigata, Verrucosisporites bulliferus and the abundance of Maranhites. The assemblages SA1 and SA2 reflect a nearshore, shallow marine depositional conditions, characterized by a high terrestrial input and variable marine influence, while the assemblage SA3 could represent a transgression during that time. The assemblages are composed of many cosmpolitan index species that support a partial correlation with Brazilian and Euramerican zonations resulting from the effects of paleolatitude and the configuration of land and sea for that time, with a narrow Rheic Ocean between northern Gondwana and Euramerica

    First record of Early Devonian (Lochkovian) flora from the Santa Rosa Formation - Alarache, Southern Bolivia

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    New information on plants and palynomorphs from Angosto de Alarache, South Bolivia, is presented. The plant remains appear at the base of the section. Dichotomizing sterile forms are assigned to Hostinella sp. and scarce stems terminated in spherical structures are interpreted as indetermined sporangia. The palynological association 1 recovered from this level contains abundant phytodebris, trilete spores, few cryptospores, algae, very poorly preserved chitinozoans, and other elements (fungi, ?lichens). Trilete spores assignable to Apiculiretusispora sp., Punctatisporites sp. and Retusotriletes sp., are obtained from the maceration of some isolated sporangia. The dichotomous branching of the stems and the trilete spores recovered from the isolated sporangia support its tracheophyte affinity. The palynological assemblage 2, obtained three metres above, contains abundant phytodebris and more diverse palynomorphs. Two new species (Retusotriletes albarinii n. sp., Acinosporites macgregorii n. sp.) are described. Based on the presence of the trilete spores Dictyotriletes emsiensis (ALLEN) MCGREGOR, Retusotriletes maculatus MCGREGOR and CAMFIELD, Apiculiretusispora plicata (ALLEN) STREEL and the absence, mainly of Verrucosisporites polygonalis LANNINGER and Urochitina loboi VOLKHEIMER et al., we propose a Lochkovian age but restricted up to the Late not latest Lochkovian, and the correlation with the lower part of the Emsiensis Zone of the Amazon Basin and the MN Zone of Western Europe. The abundance of fragmented stems of varied size and parallel to bedding planes, along with the isolated sporangia in the plant assemblage suggests a short distance transportation under low energy conditions, probably from marginal palaeoenvironments to low energy marine settings

    Morfología y estructura de la megaspora Lagenoisporites magnus (Chi y Hills) Candilier et al. 1982 del Carbonífero inferior de Bolivia

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    Se estudió la morfología y estructura de megasporas asignadas a Lagenoisporites magnus provenientes de la Formación Toregua, Grupo Retama, Tournaisiano medio-tardío de Bolivia. El análisis se realizó con microscopía óptica, fluorescencia y electrónica de barrido. Las megasporas examinadas, en su mayoría comprimidas lateralmente, presentan un cuerpo esferoidal con una gula proximal del tipo hologula. La longitud, incluyendo a la gula, es de 290-510 μm y el ancho de 184-390 μm según el eje ecuatorial.Facultad de Ciencias Naturales y Muse

    Morfología y estructura de la megaspora Lagenoisporites magnus (Chi y Hills) Candilier et al. 1982 del Carbonífero inferior de Bolivia

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    Se estudió la morfología y estructura de megasporas asignadas a Lagenoisporites magnus provenientes de la Formación Toregua, Grupo Retama, Tournaisiano medio-tardío de Bolivia. El análisis se realizó con microscopía óptica, fluorescencia y electrónica de barrido. Las megasporas examinadas, en su mayoría comprimidas lateralmente, presentan un cuerpo esferoidal con una gula proximal del tipo hologula. La longitud, incluyendo a la gula, es de 290-510 μm y el ancho de 184-390 μm según el eje ecuatorial.Facultad de Ciencias Naturales y Muse

    Prenatal diagnosis and outcome of fetuses with isolated agenesis of septum pellucidum: cohort study and meta-analysis

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    Objective: To evaluate the postnatal outcome of children with a prenatal diagnosis of apparently isolated agenesis of the septum pellucidum (ASP). Methods: A retrospective cohort study of cases of prenatally diagnosed ASP followed in two tertiary centers and a meta-analysis combining data from the cohort study with data from published studies identified in a systematic review were carried out. Only cases with apparently isolated ASP on antenatal ultrasound and/or magnetic resonance imaging and with available postnatal follow-up data were considered eligible for inclusion. The following outcomes were analyzed: incidence of chromosomal anomalies, agreement between antenatal and postnatal findings, overall incidence of septo-optic dysplasia (SOD) and incidence of major neurological disability (motor, language, coordination or behavioral disorder or epilepsy) in non-SOD children. The incidence of SOD in infants with apparently normal optic pathways on antenatal imaging was also evaluated. Results: Fifteen cases of isolated ASP, with median postnatal follow-up of 36 months (range, 12-60 months), were selected from the two centers. Six previously published studies met the inclusion criteria for the systematic review and a total of 78 cases were eligible for the analysis, including the 15 cases from our series. Genetic tests were carried out antenatally in 30 fetuses, of which two had an abnormal result (pooled proportion, 9.0% (95% CI, 1.8-20.7%); I2  = 0%). Additional or discordant imaging findings were noted postnatally in 9/70 (pooled proportion, 13.7% (95% CI, 3.5-29.0%); I2  = 63.9%) cases. Of all 78 neonates with available follow-up, SOD was diagnosed postnatally in 14 (pooled proportion, 19.4% (95% CI, 8.6-33.2%); I2  = 51.2%). In 60 cases, the optic pathways were considered to be normal on antenatal imaging, and six of these (pooled proportion, 9.1% (95% CI, 1.1-24.0%); I2  = 62.0%) were diagnosed postnatally with SOD. Of the 46 infants with available neurological follow-up who were not affected by SOD, a major neurological disability was diagnosed in three (pooled proportion, 6.5% (95% CI, 0.5-18.6%); I2  = 40.1%). Conclusions: In the vast majority of cases with a prenatal diagnosis of apparently isolated ASP, the prognosis is favorable. However, an additional anomaly is detected after birth in about 14% of cases and has a negative impact on clinical outcome. Detailed antenatal assessment of the brain and optic pathways is strongly recommended in order to identify the presence of associated anomalies. Antenatal visualization of apparently normal optic pathways does not rule out SOD. © 2021 International Society of Ultrasound in Obstetrics and Gynecology

    Usefulness of an Intrapartum Ultrasound Simulator (IUSimâ„¢) for Midwife Training: Results from an RCT

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    Introduction: We conducted a randomized study to determine whether a training session on a dedicated simulator (IUSim™) would facilitate the midwives in learning the technique of transperineal intrapartum ultrasound. Methods: Following a 30-min multimedia presentation including images and videos on how to obtain and measure the angle of progression (AoP) and the head-perineum distance (HPD), 6 midwives with no prior experience in intrapartum ultrasound were randomly split into 2 groups: 3 of them were assigned to the "training group"and 3 to the "control group."The midwives belonging to the former group were taught to measure the 2 sonographic parameters during a 3-h practical session conducted on IUSim™ under the supervision of an expert obstetrician. In the following 3 months, all the 6 midwives were asked to independently perform transperineal ultrasound during their clinical practice and to measure on the acquired images either the AoP or the HPD. The sonographic images were examined in blind by the teaching obstetrician who assigned a 0-3 score to the image quality (IQS) and to the measurement quality (MQS). Results: A total of 48 ultrasound images (24 patients) from 5 midwives were acquired and included in the study analysis. A midwife of the "training group"declined participation after the practical session. Independently from the randomization group, the image quality score (IQS + MQS) was significantly higher for the HPD compared with the AoP (2.5 ± 0.66 vs. 1.79 ± 1.14; p = 0.01). In the training group, the MQS of either AoP (2.66 ± 0.5 vs.1.46 ± 1.45. p = 0.038) and the HPD (2.9 ± 0.33 vs. 1.87 ± 0.83 p = 0.002) was significantly higher in comparison with the control group, while the IQS of both measurements was comparable between the 2 groups (1.91 ± 1.24 vs. 2.25 ± 0.865; p = 0.28). Conclusion: The use of a dedicated simulator may facilitate the midwives in learning how to measure the AoP and the HPD on transperineal ultrasound images

    ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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    Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

    Datos palinológicos de la Formación Cerro Piedras (Devónico Inferior), en la provincia de Salta, Argentina

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    La Formación Cerro Piedras expuesta en el Abra Azul, en la Sierra de Zenta (Cordillera Oriental, provincia de Jujuy), presenta ca. 400 metros de espesor. Esta unidad se inicia con un conglomerado polimíctico en la base y areniscas con estructuras entrecruzadas. La sección media se compone de una serie de lutitas marrón verdosas y areniscas finas con invertebrados (entre ellos braquiópodos) y abundante bioturbación. Hacia el tope, las lutitas se hacen más finas y se intercalan con paquetes de areniscas consolidadas con estructuras de flujo. La sucesión termina con tres bancos de areniscas sobre los que se apoya, discordantemente, la Formación Tarija. Se estudió el contenido palinológico y palinofacial de ocho muestras fértiles de la sección media, en las cuales 31 especies bien preservadas se agrupan en criptosporas, esporas trilete, microplancton y quitinozoos. La ausencia de especies típicas del Lochkoviano y la presencia de especies registradas desde el Pragiano o Emsiano (e.g., Cymbosporites? senex McGregor et Camfield, Acinosporites apiculatus (Streel) Streel, Squamispora arabica Breuer, Al-Ghazi, Al-Ruwaili, Higgs, Steemans et Wellman) sugieren que la asociación es más joven que Lochkoviano tardío. Sin embargo, la ausencia de Emphanisporites annulatus McGregor y la presencia de Dictyotriletes emsiensis Rubinstein, Melo et Steemans sugieren una edad no más joven que el Emsiano temprano. Las palinofacies fueron caracterizadas a partir de una matriz con los porcentajes relativos de palinomorfos, fitoclastos y el índice palinológico marino (PMI). Sutiles diferencias composicionales entre las distintas muestras de base a techo permiten identificar cambios paleoambientales dentro de un ambiente marino de plataforma proximal a distal. Dicha progresión ambiental está de acuerdo con propuestas hechas por otros autores para la edad que sugiere la asociación palinológica.Sesiones libresFacultad de Ciencias Naturales y Muse

    Devonian palynological assemblages from the San Antonio x-1 Borehole, Tarija Basin, northwestern Argentina

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    The palynological analysis of the 2548-3628 m interval of the San Antonio x-1 Borehole in northwestern Argentina is presented. The illustrated palynoflora is composed of 96 species represented by diverse palynological groups such as trilete spores and cryptospores (46 species), microplankton (39 species), chitinozoans (7 species), scolecodonts, and some remaining specimens in open nomenclature and as incertae sedis. One new species, Retusotriletes ottonei, is described. Thirty-four species are first records in the Argentinean Devonian. Three assemblages (SA1, SA2, and SA3) are defined based on the presence, absence, or abundance of groups of taxa. The presence of Grandispora protea and Grandispora douglastownense among others in the assemblage SA1 is indicative of a late Emsian to mid-Eifelian age. The concurrence of Acinosporites macrospinosus and A. acanthomammillatus in the assemblage SA2 is indicative of a late Eifelian-mid Givetian and is also supported by the appearance of several other species such as Chomotriletes vedugensis, Dibolisporites farraginis and Biharisporites parviornatus. An early Frasnian age is associated to the assemblage SA3 on the basis of the appearances of Lunulidia micropunctata, Pseudolunulidia laevigata, Verrucosisporites bulliferus and the abundance of Maranhites. The assemblages SA1 and SA2 reflect a nearshore, shallow marine depositional conditions, characterized by a high terrestrial input and variable marine influence, while the assemblage SA3 could represent a transgression during that time. The assemblages are composed of many cosmpolitan index species that support a partial correlation with Brazilian and Euramerican zonations resulting from the effects of paleolatitude and the configuration of land and sea for that time, with a narrow Rheic Ocean between northern Gondwana and Euramerica
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