Nuevos aportes a la palinología de las formaciones Frayle Muerto, Mangrullo y Paso Aguiar, Paleozoico Superior, Uruguay

Palynological content of nine samples extracted from borehole N° 254 “Paso de las Toscas”(DI.NA.MI.GE.) is analyzed. The samples derived from the Frayle Muerto, Mangrullo and Paso Aguiar formations, Permian in age. A total of 123 species were identified. This paper presents a systematic analysis of 25 species that are new records for Uruguay. Twelve of these species are assigned to spores, seven to pollen grains and six to acritarchs. Pollen grains are dominant in all assemblages except in the lower stratigraphic levels. Spores are present in relatively high proportions only at the lower and upper levels. Acritarchs and reworked material are found in two samples. The comparison of palynological assemblages with regional palynostratigraphic schemes suggests a Cisuralian age (probably Asselian-Artinskian) for the lower stratigraphic level (Cristatisporites Biozone for Argentina, Vittatina costabilis Biozone for Brasil and Cristatisporites inconstans–Vittatina saccata Biozone for Uruguay) and an age between the late Cisuralian and the Guadalupian for the remaining levels (Striatites Biozone for Argentina, Lueckisporites virkkiae Biozone for Brasil and Striatoabieites anaverrucosus – Staurosaccites cordubensis Biozone for Uruguay).Se analiza el contenido palinológico de nueve muestras pertenecientes a la perforación N° 254 “Paso de las Toscas” (DI.NA.MI.GE.) que abarcan las formaciones Frayle Muerto, Mangrullo y Paso Aguiar, de edad Pérmica. De un total de 123 especies identificadas, se analizan desde el punto de vista sistemático las 25 especies que son nuevas citas para Uruguay, de las cuales 12 corresponden a esporas, siete a granos de polen y seis a acritarcas. Los granos de polen predominan en todas las asociaciones salvo en los niveles estratigráficamente inferiores. Las esporas se presentan en proporciones relativamente elevadas únicamente en el nivel inferior y en los niveles superiores. Las acritarcas y el material retrabajado están presentes en dos muestras. La comparación de las asociaciones palinológicas con los esquemas palinoestratigráficos regionales sugiere una edad Cisuraliense, probablemente comprendida entre el Asseliense y el Artinskiense, para el nivel estratigráfico inferior (Biozona Cristatisporites para Argentina, Biozona Vittatina costabilis para Brasil y Biozona Cristatisporites inconstans–Vittatina saccata para Uruguay) y una edad entre el Cisuraliense Tardío y el Guadalupiense para los niveles restantes (Biozona Striatites para Argentina, Biozona Lueckisporites virkkiae para Brasil y Biozona Striatoabieites anaverrucosus – Staurosaccites cordubensis para Uruguay)

General characteristics of airbone pollen in Montevideo city, Uruguay

Características generales del polen aéreo en Montevideo, Uruguay. Este trabajo analiza las variaciones diarias y estacionales y la influencia de las condiciones meteorológicas en lasconcentraciones de polen en el período de junio de 2011 a mayo de 2014. Fueron identificados noventa y tres taxones polínicos, correspondientes a 49 tipos arbóreos y a 44 tipos polínicos herbáceos. Los tipos polínicos más importantes fueron Poaceae, Platanus, Cupressaceae/Taxaceae, Eupatorieae type, Celtis, Urticaceae, Myrtaceae, Casuarina, Amaranthaceae, Cyperaceae, Fraxinus, Arecaceae, Ricinus communis, Moraceae, Myrsine, Ambrosia, Quercus y Pinaceae. Se registró polen todos los días del año, pero el período de polinización principal se registró desde agosto a abril. Se observaron diferencias interanuales en los índices polínicos, en las fechas y concentraciones diarias máximas, así como en las concentraciones mensuales acumuladas. La temperatura media, la humedad relativa del aire y la dirección y velocidad del viento fueron las variables meteorológicas con mayor influencia sobre el polen aéreo. Las concentraciones polínicas excedieron los umbrales considerados como moderados o altos un promedio de 182 días al año.This paper analyses daily and seasonal variations on pollen concentrations and the influence of meteorological conditions on the airborne pollen from June 2011 to May 2014. Data is also compared with results from a previous pollen survey from 2000-2001. Ninety-three taxa were identified, belonging to 49 trees and shrub taxa and 44 herbaceous taxa. The most important pollen sources were Poaceae, Platanus, Cupressaceae/Taxaceae, Eupatorieae type, Celtis, Urticaceae, Myrtaceae, Casuarina, Amaranthaceae, Cyperaceae, Fraxinus, Arecaceae, Ricinus communis, Moraceae, Myrsine, Ambrosia, Quercus, and Pinaceae. Pollen was recorded all year round but the main pollen season was from August to April. Inter-annual differences were observed on pollen indexes, dates and values of daily peak concentrations and monthly accumulated concentrations. Temperature, relative air humidity and wind speed and direction seem to be the most influential meteorological variables on pollen concentrations. The number of days that pollen concentrations are above moderate and high thresholds levels is estimated and woody and non-woody pollen concentrations would be above moderate levels on average 182 days per year

Late Miocene mammalian burrows in the Camacho Formation of Uruguay reveal a complex community of ecosystem engineers

We report fossil mammal burrows from backshore beach facies in the Camacho Formation of southern Uruguay, of Late Miocene (Huayquerian SALMA) age. The presence of desiccation cracks and rhizoliths indicate the occurrence of relatively extended periods of subaerial exposure and the incipient development of vegetation. The analysis of the burrows' spatial extent, size, and structure reveals the existence of exceptionally well-preserved and intercrossing tunnel systems. We show the existence of different size classes of burrows, which indicate that at least four different taxa were responsible for their construction. Considering the inferred body masses of the trace makers obtained from allometric relationships and the body masses of taxa recovered for the Camacho Formation, the burrows may have been produced by a combination of the following mammals: one of several rodents, notoungulates, cingulates, folivorans, and a carnivoran. The fossil association represents an exceptional case of a community of ecosystem engineers in the Late Miocene of southeastern South America.ANII: POS_NAC_2014_1_10237

Desinfección de agua residual doméstica mediante un sistema de tratamiento acoplado con fines de reúso

La posibilidad de combinar sistemas biológicos con tecnologías avanzadas de oxidación (TAO) para el tratamiento de aguas residuales hace imprescindible valorar la utilidad de la combinación de tales tecnologías, ajustando los diseños y condiciones de operación. Este proyecto de investigación abordó la desinfección de agua residual doméstica con fines de reutilización, evaluando el potencial de combinación de un proceso fotocatalítico solar que utiliza peróxido de hidrógeno (UV solar/H2O2) con un sistema de humedales construidos de flujo subsuperficial horizontal (HC FSSH), como alternativa para el reúso del agua residual doméstica para riego. Para ello, se construyó un fotorreactor en tubos de polimetilmetacrilato (PMMA) expuesto a la radiación solar UV, que opera en modo batch, y se evaluó el efecto de la fotólisis y adición de peróxido de hidrógeno, aplicando dosis de 3, 30 y 300 mgl-1 de H2O2. La eficiencia de eliminación de coliformes totales y fecales fue evaluada considerando el efecto de radiación ultravioleta, dosis de peróxido de hidrógeno y tratamiento con HC FSSH plantados con Cyperus ligularis. Los resultados indicaron que es posible obtener un grado de desinfección de 99.999% de coliformes fecales y totales cuando se acoplan la TAO y el sistema biológico con un tiempo de retención de tres días en el HC FSSH y cinco horas en el fotorreactor

La diversidad palinológica y los cambios climáticos en el Paleozoico Superior en Brasil y Uruguay

We have analysed the diversity of the late Paleozoic palynoflora of the Paraná (Brazil and Uruguay), Parnaíba and Amazon (Brazil) basins using already published data. In order to do this the total diversity and diversity with range-through approach curves were built up, as well as Foote’s appearance and disappearance rates at the generic level. These parameters were also obtained separately for each group of sporomorphs. An important increase in diversity in the Asselian and Sakmarian and a posterior decrease until the Lopingian were observed. The values of the appearance rates were higher than those of disappearance and they peaked in the Asselian, while the highest disappearances took place in the Capitanian and, to a lesser extent, in the Sakmarian. On the other hand, spores and pollen grains show some differences in the general diversity trend. However, there are differences in the patterns of appearance and disappearance. Despite possible biases, mainly related to the collecting effort, the diversity curves and appearance and disappearance rates obtained are congruent with the climatic phases proposed for this region in these periods. The increase in the number of palynomorph genera is associated to the early Permian climatic amelioration whilst a decrease in diversity is related to the beginning of an arid phase.Se analizó la diversidad de la palinoflora correspondiente a estratos del Paleozoico superior de las cuencas de Paraná (Brasil y Uruguay), Parnaíba y Amazonas (Brasil), utilizando datos previamente publicados. Se elaboraron curvas de diversidad total y diversidad calculadas mediante el método range-through y se calcularon los índices de aparición y desaparición de los diferentes géneros utilizando como herramienta el índice de Foote. También se analizaron esos parámetros en diferentes grupos de esporomorfos por separado. Se observó un aumento importante de la diversidad en el Asseliano y Sakmariano y una posterior disminución gradual hasta el Lopingiano. Los valores de los índices de aparición fueron más importantes que los de desaparición y se dieron en el Asseliano, mientras que las mayores desapariciones se observaron en el Capitaniano y en menor medida en el Sakmariano. Por otra parte, las esporas y los granos de polen presentan algunas diferencias en la tendencia general de diversidad. Sin embargo, se aprecian diferencias en los patrones de aparición y desaparición. A pesar de los posibles sesgos, fundamentalmente relacionados con el esfuerzo de colecta, existe cierta coherencia entre la diversidad, los índices de apariciones y desapariciones y las fases climáticas propuestas para esa edad en la región. El cambio hacia un clima más templado ocurrido en el Pérmico inferior estaría asociado a un aumento en el número de géneros de palinomorfos mientras que el comienzo de una fase más árida estaría relacionado a una disminución en la diversidad

A synthesis of palynological data from the Lower Permian Cerro Pelado Formation (Paraná Basin, Uruguay): A record of warmer climate stages during Gondwana glaciations

This paper presents a synthesis of the palynological record in the Cerro Pelado Formation deposits (Lower Permian, Paraná basin, Cerro Largo Department, north eastern Uruguay) based on pre-existing data and new findings. The successions studied in this formation consist mainly of non-marine to glacial-marine mudstones and sandy mudstones. The palynological assemblages yielded by 32 samples collected from two outcrops and thirty borehole samples demonstrate that not significant floral changes took place through the considered stratigraphic range. The correlation of these assemblages with biostratigraphic palynozones, proposed previously for the Paraná/ Chacoparaná Basin of Brazil, Argentina and Uruguay point to their Early Permian age. The most widespread spore genera in these assemblages are Punctatisporites, Lundbladispora, Vallatisporites and Granulatisporites. Among pollen grains, Caheniasaccites, Vittatina, Potonieisporites, Protohaploxypinus and Plicatipollenites are the most representative. Palynomorphs assigned to Chlorophyta, Prasinophyta, and acritarchs indicate the development of brackish to fresh water lacustrine environments. The results from the facies and palynological analyses suggest that these deposits were formed during interglacial or postglacial warmer climatic episodes. This fact would agree well with the proposal that Gondwana glaciations were characterized by discrete glacial phases (with multiple glacial lobe advance-retreat phases) alternating with warmer climatic episodes. These episodes could be recognized thanks to sub-glacial and melt water related continental deposits that would bear characteristic palynological assemblages, like the recorded in the Cerro Pelado Fm. successions

Permian palynofloral changes in Uruguay and their relationships with lithostratigraphic units

<div><p>A total of 77 samples from Permian strata of Uruguay were extracted from eight boreholes drilled by Dirección Nacional de Minería y Geología of Uruguay, as well as from two outcrops located in El Barón Creek (1 sample) and on Route 26, east of Melo City (1 sample). These samples correspond to the San Gregorio-Cerro Pelado, Tres Islas, Fraile Muerto, Mangrullo and Paso Aguiar Formations from the early Cisuralian to approximately the early Guadalupian. To quantify change in palynological assemblages, 188 species of sporomorphs were identified and binned by geological formations. Extinction and originations were calculated between formations. There was no qualitative change in species composition in the San Gregorio-Cerro Pelado, Tres Islas and Fraile Muerto Formations. A turnover in sporomorph species assemblage was observed between the Fraile Muerto and the Mangrullo Formation, which coincides temporally with the onset of an arid climatic phase for the region. Plant assemblages were analysed taking into account that the botanical affinities of the sporomorphs show no significant change through the sampled time interval.</p> </div

Sampling biases and Paleozoic sporomorphs diversity dynamics in Western Gondwana strata

A dataset consisting of presence-absence data of 137 pollen and spore genera was elaborated with published sources from Pennsylvanian and Permian Atlantic (Paraná, Parnaíba, Amazonas, and Claromecó) and Pacific (Paganzo, Tarija, and Madre de Dios) basins of South America. The richness and origination, extinction, and sampling rates of sporomorphs were analyzed in order to address the effect of sampling biases over diversity estimations. Richness and sampling were estimated using the recently developed True Richness estimated using a Poisson Sampling (TRiPS) model. Origination, extinction, and sampling rates were estimated with Inverse Survivorship Models. The TRiPS analysis showed changes in richness during the studied interval. The highest richness was observed for the Cisuralian, and the lowest richness was recovered for the Pennsylvanian and Guadalupian. The best supported Inverse Survivorship Model revealed that the highest origination values occurred between the Gzhelian and Asselian, whereas the highest observed extinction rate occurred between the Kungurian and the Roadian. In particular, pollen grains showed higher net diversification than spores, while spores showed higher turnover than pollen grains. Also, an alternation in richness dominance was observed at the beginning of the Permian, with pollen grains showing higher richness after the Artinskian. Changes in total sporomorphs diversity, as well as differences between spores and pollen grains, may be related to changing climatic conditions in Western Gondwana during the late Paleozoic (from icehouse to greenhouse conditions) that could impact differently over plant communities. Although the fossil palynomorph record has been widely used as a biostratigraphic tool, our results highlight its importance and usefulness for the study of plant communities and their evolution in the past.Fil: Beri Castagnini, Ángeles. Universidad de la República; UruguayFil: Martínez Blanco, Ximena. Universidad de la República; UruguayFil: Varela, Luciano. Universidad de la República; UruguayFil: Di Pasquo Lartigue, Maria. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Alves de Souza, Paulo. Universidade Federal do Rio Grande do Sul; Brasi

SGLT2 Inhibitors and nephroprotection in diabetic kidney disease: From mechanisms of action to the latest evidence in the literature

Type 2 Diabetes Mellitus constitutes a major problem in public health worldwide. The disease poses a high risk of severe microvascular and macrovascular complications. Diabetic kidney disease is the most common cause of end-stage chronic kidney disease and contributes to the increasing morbidity and mortality associated to diabetes. Sodium-glucose contransporter-2 inhibitors (SGLT2 inhibitors) are the latest oral diabetic medications, which exhibit a great nephroprotective potential, not only by improving glycemic control, but also by glucose-independent mechanisms, such as decreasing blood pressure and other direct renal effects. We conduct a literature review based on the most recent scientific evidence with the goal to elucidate the postulated mechanisms of action of SGLT2 inhibitors in diabetic kidney disease, which are the base of the beneficial clinical effects that are seen in the condition

Biomarkers in acute kidney injury

Acute kidney injury is a common condition associated with high morbidity and short-term mortality. Its pathophysiology varies according to the numerous conditions associated with its genesis. Biomarkers allow detecting changes at the level of kidney function; therefore, they play an important role in the prevention, early diagnosis, therapeutic response and prognosis of acute kidney injury. The search for biomarkers for acute kidney injury began over 15 years ago; initially, only serum creatinine was available for diagnosis. However, throughout history, great advances have been made in research, which have allowed the finding of new biomarkers in order to improve the health and quality of life of patients. A narrative review of the literature is carried out on the basis of available scientific evidence to clarify the role and importance of biomarkers in the context of acute renal injury