An in situ shelly fauna from the lower Paleozoic Zapla diamictite of northwestern Argentina: implications for the age of glacial events across Gondwana

A shelly fauna from the upper part of the Zapla glacial diamictite includes thelingulate brachiopod Orbiculoidea radiata Troedsson, the rhynchonelliforms Dalmanella cf. testudinaria (Dalman) and Paromalomena sp., the bivalve Modiolopsis? sp., and the trilobite Dalmanitina subandina Monaldi and Boso. Both taphonomic and paleoecologic data indicate a lack of transport reflecting the original community. The assemblage is closely comparable to the widespread latest Ordovician Hirnantia-Dalmanitina fauna. The Hirnantian age of the Zapla diamictite is further corroborated by the record of the northern Gondwana chitinozoans Spinachitina cf. oulebsiri Paris and Desmochitina minor typicaEisenack. The graptolites and chitinozoans from the overlying Lipeón Formation indicate that the postglacial transgression took place in the earliest Llandovery (P. acuminatus Biozone). According to the tectonosedimentary evidence, the Early Silurian age of the Cancañiri and San Gabán diamictites of north-central Bolivia and south Peru based on their palynological record is more likely the age of posglacial gravity flows and not that of the glaciation. We support the hypothesis that the weakly lithified glacigenic deposits ofHirnantian age were reworked and redistributed by high-energy marine processes during the postglacial transgression and then transported to the adjacent deep-marine trough. Ironrich horizons have been recognized in many basins of southern South America reflecting eustatic and paleoclimatic fluctuations. Most of them formed during the early stages of the postglacial transgression at the Ordovician/Silurian transition and are associated with low sedimentation rates and condensed intervals. The mild maritime postglacial climate, the increasing atmospheric CO2, and possibly the presence of incipient vegetated areas led toextensive weathering of glacigenic sediments supplying iron into the marine system to form ferruginous deposits. The sea level fall related to the peak of glaciation is recorded by both paleovalley incision and a sharp subaerial to subglacial unconformity. The transgressive systems tract starts with fluvio-estuarine deposits within incised valleys followed by widespread deposition of subtidal to open marine organic-rich shales onlapping regionally the basement rocks. The recognition of key stratigraphic markers (e.g. sequence boundary, flooding surface, ferruginous beds), alongside reliable micro and macropaleontological evidence allow a more accurate correlation between the Central Andean Basin of Peru, Bolivia and NW Argentina, the W Puna region, the Paraguayan and Brazilian sectors of the Paraná Basin, the Precordillera Basin of W Argentina, and the Cape Basin of South Africa.Fil: Benedetto, Juan Luis Arnaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Halpern, Karen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: de la Puente, Graciela Susana. Universidad Nacional del Comahue. Facultad de Ingeniería. Departamento de Geología y Petróleo; ArgentinaFil: Monaldi, Cesar Ruben. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentin

Association between Caries, Obesity and Insulin Resistance in Mexican Adolescents

Aim: To determine the association among dental caries, obesity and insulin resistance in Mexican adolescents. Methods: Body Mass Index, obesity (OB) blood pressure, insulin level, insulin resistance (IR), triglycerides level, serum HDL-cholesterol (cHDL), DMFT index and salivary flow were measured. Results: Anthropometric measures showed a significant statistical difference (p \u3c 0.05). Insulin level was 8.98 for healthy subjects, whereas for OB-IR group was 25.35, there was a statistical significant difference (p \u3c 0.05). Triglycerides level was 88.50 for healthy subjects and 169.40 mg/dL for OB-IR; cHDL was 52.88 for healthy and 41.82 mg/dL for OB-IR group, both showed a statistically significant difference (p \u3c 0.05). Salivary flow was 4.30 for healthy and for OB-IR group was 5.48 ml/min showed a significant statistical difference (p \u3c 0.05). DMFT index was 3.02 for healthy and for OB-IR adolescents was 4.78, showed a significant statistical difference (p \u3c 0.05). The caries component of DMFT index was 1.84 for healthy and was 3.52 for OB-IR adolescents, showed a significant statistical difference (p \u3c 0.05). According to the multivariate analysis, DMFT (OR=3.10; IC95%=0.20-1.02, p=0.042) and decay (OR=3.30; IC95%=0.19-1.0, p=0.011) were associated with subjects with OB-IR. Conclusion: OB-IR Mexican adolescents showed a positive association with DMFT

Physical and hydrological properties of volcanic soils affected by recent wildfires in Patagonia

Los incendios forestales o casionan importan tes impactos sobre el suelo ya que pu eden consumir gran parte de la cobertura vegetal y materia orgánica, a lterando su fertilidad física y rég imen hidrológ ico. En este trabajo evaluamos algunas propiedades de los suelos de origen volcánico a fectados por incendios recientes. Se seleccionaron dos áreas de estudio, correspon dientes a bosques de Austrocedrus chilensis, ubicadas en las provincias de Chubut y Río Negro, Argen tina, afectadas por in cendios o curridos en el 2008 y 2009, respectivamente. En cada sector se iden tificaron dos niveles de disturbio por fuego y un área con trol. Se d eterminó la tasa de infiltración y se tomaron muestras compuestas del suelo mineral a dos profundidades (0 - 2 . 5 cm y 2 . 5 - 5 cm) y se evaluó densidad aparente (DA), humedad equivalen te (HE), textura, hidro fobicidad y materia orgánica (MO). El paso d el fuego produjo una fuerte disminución en los contenidos d e MO y HE en los suelos con un alto nivel de d isturbio. El fuego aumentó la repelencia al agua, prin cipalmen te en los suelos afectados por el incendio más reciente, en los que se detectó una mayor hidrofob icidad en las muestras de 2,5 a 5 cm. Los máximos valores se registraron en los suelos con un alto nivel de disturbio correspondiendo a extremadamente hidrofób icos. Con trariamente a lo esperado, el fuego no afectó significativamente la DA, in filtra ción y la textura de los suelos. La evaluación de las modificaciones en el suelo permite interpretar el impacto del fuego sobre la calidad de los suelos y la posterior recup eración de la vegetación.Wildfire cause major impacts on the soil due the loss of vegetation cover and organic matter, altering physica l and h ydrologica l soil properties. We evaluated some properties of volcanic soils affected by recent fires. Two study sites with Austrocedrus chilensis forests were selected in Chubut and Río N egro provinces, Argen tina, wh ich were affected b y fires in February 2008 and January 2009, respectively. In each site, two levels of d isturbance b y fire were id entified and unburned soil was used as control. Infiltration rate was d etermined and samples of the mineral soil a t two d epths (0 - 2.5 cm and 2.5 - 5 cm) w ere randomly taken for bulk density ( BD), available water capacity (AWC), texture, hydrophob icity and organic matter (OM) determinations. The results showed, one year after fire, d ecrease in OM and AW C in burned soils with high level of disturbance by fire. Hydrophobicity greatly varied, but tended to increase at 2.5 - 5 cm, mainly in th e most recent w ildfire. The maximum values were observed in the burned soil with h igh level of d isturbance b y fire, bei ng extremely h ydrophobic. The wild fire did not significantly a ffect the texture, bu lk density and infiltration rate of soils. The evaluation of changes in ph ysical and hydrolog ical soils properties is useful to assess the impact of fire on soil quality and the subsequen t recovery o f vegetation. These changes may be very variable a ccording to soil and climatic conditions and characteristics of fire.Fil: Morales, Daniela Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: la Manna, Ludmila Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Rostagno, Cesar Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentin

Impacto del fuego sobre el comportamiento hidrológico del suelo en un bosque de ciprés

Los incendios forestales, especialmente los de gran severidad, pueden acelerar los procesos de erosión del suelo. La eliminación de la cobertura vegetal y de la materia orgánica del suelo da lugar a cambios en los procesos hidrológicos al reducir la intercepción de las precipitaciones y modificar la estructura del suelo superficial. El objetivo de este trabajo fue caracterizar el comportamiento hidrológico de un suelo forestal luego del paso del fuego mediante un ensayo de lluvia simulada. El sitio de estudio fue ubicado en el noroeste de la provincia de Chubut dentro de un área afectada por un incendio ocurrido en el 2008. La vegetación correspondió a un bosque de Austrocedrus chilensis y los tratamientos considerados fueron: bosque quemado y sin cobertura vegetal, bosque quemado luego de 1 año del incendio y control. Se evaluó la tasa de infiltración, el escurrimiento y la producción de sedimentos mediante el empleo de lluvia simulada. El fuego afectó de manera significativa la tasa de infiltración, el escurrimiento superficial y la producción de sedimentos. En los suelos afectados por el fuego, se registró una disminución en la infiltración del suelo y un aumento de la escorrentía y producción de sedimentos.Fil: la Manna, Ludmila Andrea. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centro de Investigación y Extensión Forestal Andino Patagónico; ArgentinaFil: Rostagno, Cesar Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Morales, Daniela Vanesa. Centro de Investigación y Extensión Forestal Andino Patagónico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentin

ACCase 6 is the essential acetyl-CoA carboxylase involved in fatty acid and mycolic acid biosynthesis in mycobacteria

Mycolic acids are essential for the survival, virulence and antibiotic resistance of the human pathogen Mycobacterium tuberculosis. Inhibitors of mycolic acid biosynthesis, such as isoniazid and ethionamide, have been used as efficient drugs for the treatment of tuberculosis. However, the increase in cases of multidrug-resistant tuberculosis has prompted a search for new targets and agents that could also affect synthesis of mycolic acids. In mycobacteria, the acyl-CoA carboxylases (ACCases) provide the building blocks for de novo fatty acid biosynthesis by fatty acid synthase (FAS) I and for the elongation of FAS I products by the FAS II complex to produce meromycolic acids. By generating a conditional mutant in the accD6 gene of Mycobacterium smegmatis, we demonstrated that AccD6 is the essential carboxyltransferase component of the ACCase 6 enzyme complex implicated in the biosynthesis of malonyl-CoA, the substrate of the two FAS enzymes of Mycobacterium species. Based on the conserved structure of the AccD5 and AccD6 active sites we screened several inhibitors of AccD5 as potential inhibitors of AccD6 and found that the ligand NCI-172033 was capable of inhibiting AccD6 with an IC50 of 8 ìM. The compound showed bactericidal activity against several pathogenic Mycobacterium species by producing a strong inhibition of both fatty acid and mycolic acid biosynthesis at minimal inhibitory concentrations. Overexpression of accD6 in M. smegmatis conferred resistance to NCI-172033, confirming AccD6 as the main target of the inhibitor. These results define the biological role of a key ACCase in the biosynthesis of membrane and cell envelope fatty acids, and provide a new target, AccD6, for rational development of novel anti-mycobacterial drugsFil: Kurth, Daniel German. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Gago, Gabriela Marisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: de la Iglesia, Agustina Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Bazet Lyonnet, Bernardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Lin, Ting Wang. University of California; Estados UnidosFil: Morbidoni, Héctor Ricardo. Universidad Nacional de Rosario. Facultad de Ciencias Médicas; ArgentinaFil: Tsai, Shiou Chuan. University of California; Estados UnidosFil: Gramajo, Hugo Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin

An evaluation of International Reference Ionosphere electron density in the polar cap and cusp using EISCAT Svalbard radar measurements

Publisher's version, source: http://doi.org/10.5194/angeo-34-751-2016.Incoherent scatter radar measurements are an important source for studies of ionospheric plasma parameters. In this paper the EISCAT Svalbard radar (ESR) long-term database is used to evaluate the International Reference Ionosphere (IRI) model. The ESR started operations in 1996, and the accumulated database up to 2012 thus covers 16 years, giving an overview of the ionosphere in the polar cap and cusp during more than one solar cycle. Data from ESR can be used to obtain information about primary plasma parameters: electron density, electron and ion temperature, and line-of-sight plasma velocity from an altitude of about 50 and up to 1600 km. Monthly averages of electron density and temperature and ion temperature and composition are also provided by the IRI model from an altitude of 50 to 2000 km. We have compared electron density data obtained from the ESR with the predicted electron density from the IRI-2016 model. Our results show that the IRI model in general fits the ESR data well around the F2 peak height. However, the model seems to underestimate the electron density at lower altitudes, particularly during winter months. During solar minimum the model is also less accurate at higher altitudes. The purpose of this study is to validate the IRI model at polar latitudes

Primary central nervous system lymphoma presenting as isolated oculomotor nerve palsy

AbstractThe authors report an unusual case of primary central nervous system lymphoma presenting with isolated pupil-involved oculomotor nerve palsy. Magnetic resonance imaging demonstrated leptomeningeal involvement of the midbrain and interpeduncular cistern, a single hypothalamic lesion, and intraventricular involvement. Diffuse large B-cell lymphoma was confirmed by stereotactic intraventricular biopsy. Combination chemotherapy with methotrexate, vincristine, procarbazine and rituximab was instituted with resolution of oculomotor nerve palsy and complete disease remission. An interdisciplinary approach involving neurosurgeons, neuroradiologists, neuropathologists and neurologists is crucial in the management of primary central nervous system lymphoma

Presas del búho campestre (Asio flammeus) en un agroecosistema subtropical de Paraguay

Fil: Torres Monges, Julio Cesar. Universidad Nacional de Asuncion; ParaguayFil: Teta, Pablo Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: De la Sancha, Noé U.. Chicago State University. Integrative Research Center; Estados Unidos. The Field Museum of Natural History; Estados Unido