METAXYTHERIUM MEDIUM (MAMMALIA: SIRENIA) FROM UPPER MIOCENE SEDIMENTS OF THE ARENARIA DI PONSANO FORMATION (TUSCANY, ITALY)

Records of Metaxytherium medium (Mammalia: Sirenia) from Tononian (Late Miocene) sediments from che Arenaria di Ponsano Formation (Tuscany, Italy) are described. They consist of fragmentary specimens, including several partial cranial elements representing at least three skulls, two humeri, fragments of venebrae and some incomplete ribs. The new Tuscan records confirm che wide diffusion of Metaxytherium in the Mediterranean during the Miocene. This sirenian's occurrence in the Arenaria di Ponsano sediments is in accordance with the shelf environment indicated by other fossils. The low sea bottom was at least partially covered by segrass meadows, the food source of this dugongid.&nbsp

KOGIA PUSILLA FROM THE MIDDLE PLIOCENE OF TUSCANY (ITALY) AND A PHYLOGENETIC ANALYSIS OF THE FAMILY KOGIIDAE (ODONTOCETI, CETACEA)

A partial skull of an odontocete cetacean from Middle Pliocene sediments of Monte Voltraio (Pisa Province, Tuscany, Italy) is examined. This fossil, erroneously referred to the family Ziphiidae and described in the past as holotype of the species Hyperoodon pusillus, is assigned here to the genus Kogia (family Kogiidae). The species Kogia pusilla is redescribed and compared to the living species K. breviceps and K. simus. Phylogenetically, an old separation (at least in the Lower Miocene) of Kogiidae and Physeteridae is suggested. The lack of substantiated kogiid records until the Upper Miocene is probably due to the rarity of these cetaceans. Phyletic analysis within the Kogiidae is undertaken and supposed apomorphies in the morphology and/or the extension of the supracranial basin that houses the large air sacs and the spermaceti organ are considered.&nbsp

Biogeographic and palaeoclimatic relationships of the Middle Pliocene ichthyofauna of the Samoggia Torrent (Bologna, Italy)

New Middle Pliocene ichthyofauna (2.4-2.2 Ma) from central-eastern Italy (Samoggia Torrent, Bologna) are described. These ichthyolites were found in a rather thin laminated layer that was deposited after the 2.4 Ma climatic crisis. The origin of this deposit, in which 31 taxa have been classified, is to be related to anoxic events on a regional and, probably, supraregional scale. This ichthyofaunistic association, which consists of living genera, is characterized by a clearcut predominance of mesopelagic species. The palaeoclimatic characters of these ichthyofauna indicate subtropical-type waters, while from a palaeobiogeographic point of view there is a close relationship with the present-day Atlantic-Mediterranean bioprovince. The Samoggia deposit has yielded six taxa that are absent or only occasionally present in the Mediterranean: one of these, Spratelloides gracilis, is exclusive of the Indo-Pacific bioprovince

El aprendizaje de extensionistas y la reflexión desde la acción. Prácticas y disposiciones reflexivas

This paper contributes to understand the non-formal learning processes that take place in the context of rural extension workers’ practices in North-eastern Argentina. The objective of this research was to understand the learning processes of extension workers that take place in the interaction among extensionists, and between them and farmers, drawing on reflexion on practice as main analytical dimension. In terms of methodology, individual interviews and focus groups were conducted with extensionists that work in the province of Corrientes in public national extension institutions. Transcriptions were analyzed with the support of Atlas.Ti software focusing on three analytical axes: learning in practice, idea of learning that extension workers have, and group work. This article recovers and highlights the importance of understanding the dynamics that characterize learning processes based on reflection on practice, having in mind extensionists’ creative activity in the context of their reflective capacity and group work.El presente trabajo es un aporte a la comprensión de las formas de aprendizaje no formales que se sustancian en las prácticas de los extensionistas rurales del nordeste argentino. La investigación planteó como objetivo comprender los procesos de aprendizaje de los extensionistas a partir de analizar el vínculo entre pares, y entre extensionistas y productores, tomando como eje analítico principal la reflexión sobre la práctica. Metodológicamente el trabajo se apoya en el análisis de entrevistas individuales y grupos focales realizados a extensionistas que se desempeñan en la provincia de Corrientes en instituciones nacionales públicas de extensión rural. Para el análisis del material se utilizó como soporte el programa Atlas.Ti focalizando la reflexión en tres dimensiones de análisis: el aprendizaje en la práctica, la idea de aprendizaje que tienen los extensionistas y el trabajo en equipo. El artículo recupera y resalta la importancia de la comprensión de las dinámicas características de los procesos de aprendizaje que se apoyan en la reflexión sobre la práctica, teniendo presente la actividad creativa de los extensionistas en el ejercicio de su capacidad reflexiva y del trabajo en equipo

A well preserved skeleton of the fossil shark Cosmopolitodus hastalis from the late Miocene of Peru, featuring fish remains as fossilized stomach contents

Both the preservation of the poorly mineralized skeleton of sharks and the preservation of stomach contents are rarely observed in the fossil record. Here we report on a partial skeleton of a lamniform shark, including portions of the visceral arches and the anterior segment of the vertebral column, collected from the late Miocene beds of the Pisco Formation exposed at Cerro Yesera (Ica Desert, South Peru). Based on the morphology of the preserved teeth, this specimen was determined as a juvenile of the extinct lamnid species Cosmopolitodus hastalis. The shark skeleton includes remains of fish (featuring a pilchard determined as Sardinops sp. cf. S. sagax) in the abdominal region. These fish remains are interpreted herein as the fossilized stomach contents of the shark. For the first time, piscivory is demonstrated in a juvenile individual of Cosmopolitodus hastalis. This result is consistent with the current knowledge about the feeding habits of immature individuals of extant lamniform shark species (including Carcharodon carcharias and Isurus oxyrinchus). Our report further outlines the fundamental role of schooling pilchards in the late Miocene trophic chains of the highly productive coastal waters off present South Peru. Moreover, the find of this well preserved shark skeleton strengthens the qualification of the Pisco Formation as a Fossil-Lagerstätte, and emphasizes the role of early mineralization processes in cases of exceptional preservation

Extension workers’ learning and reflection from action: practices and reflective dispositions

El presente trabajo es un aporte a la comprensión de las formas de aprendizaje no formales que se sustancian en las prácticas de los extensionistas rurales del nordeste argentino. La investigación planteó como objetivo comprender los procesos de aprendizaje de los extensionistas a partir de analizar el vínculo entre pares, y entre extensionistas y productores, tomando como eje analítico principal la reflexión sobre la práctica. Metodológicamente el trabajo se apoya en el análisis de entrevistas individuales y grupos focales realizados a extensionistas que se desempeñan en la provincia de Corrientes en instituciones nacionales públicas de extensión rural. Para el análisis del material se utilizó como soporte el programa Atlas.Ti focalizando la reflexión en tres dimensiones de análisis: el aprendizaje en la práctica, la idea de aprendizaje que tienen los extensionistas y el trabajo en equipo. El artículo recupera y resalta la importancia de la comprensión de las dinámicas características de los procesos de aprendizaje que se apoyan en la reflexión sobre la práctica, teniendo presente la actividad creativa de los extensionistas en el ejercicio de su capacidad reflexiva y del trabajo en equipo.This paper contributes to understand the non-formal learning processes that take place in the context of rural extension workers’ practices in North-eastern Argentina. The objective of this research was to understand the learning processes of extension workers that take place in the interaction among extensionists, and between them and farmers, drawing on reflexion on practice as main analytical dimension. In terms of methodology, individual interviews and focus groups were conducted with extensionists that work in the province of Corrientes in public national extension institutions. Transcriptions were analyzed with the support of Atlas.Ti software focusing on three analytical axes: learning in practice, idea of learning that extension workers have, and group work. This article recovers and highlights the importance of understanding the dynamics that characterize learning processes based on reflection on practice, having in mind extensionists’ creative activity in the context of their reflective capacity and group work.Fil: Monzón, Marisa Cristina. Universidad de la Cuenca del Plata; ArgentinaFil: Brites, Walter Fernando. Universidad de la Cuenca del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Estudios Sociales y Humanos. Universidad Nacional de Misiones. Facultad de Humanidades y Ciencias Sociales. Instituto de Estudios Sociales y Humanos; ArgentinaFil: Landini, Fernando Pablo. Universidad de la Cuenca del Plata. Secretaría de Políticas del Conocimiento. Instituto de Investigaciones Científicas (Sede Posadas); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentin

A rhinopristiform sawfish (Genus pristis) from the middle eocene (lutetian) of southern Peru and its regional implications

Modern sawfishes (Rhinopristiformes: Pristidae) are circumglobally distributed in warm waters and are common in proximal marine and even freshwater habitats. The fossil record of modern pristid genera (i.e., Pristis and Anoxypristis) dates back to the early Eocene and is mostly represented by isolated rostral spines and oral teeth, with phosphatised rostra representing exceptional occurrences. Here, we report on a partial pristid rostrum, exhibiting several articulated rostral spines, from middle Eocene strata of the Paracas Formation (Yumaque Member) exposed in the southern Peruvian East Pisco Basin. This finely preserved specimen shows anatomical structures that are unlikely to leave a fossil record, e.g., the paracentral grooves that extend along the ventral surface of the rostrum. Based on the morphology of the rostral spines, this fossil sawfish is here identified as belonging to Pristis. To our knowledge, this discovery represents the geologically oldest known occurrence of Pristidae from the Pacific Coast of South America. Although the fossil record of pristids from the East Pisco Basin spans from the middle Eocene to the late Miocene, sawfishes are no longer present in the modern cool, upwelling-influenced coastal waters of southern Peru. Given the ecological preferences of the extant members of Pristis, the occurrence of this genus in the Paracas deposits suggests that middle Eocene nearshore waters in southern Peru were warmer than today. The eventual disappearance of pristids from the coastal waters off southern Peru might be interpreted as reflecting the late Cenozoic trend of strengthening of the Humboldt Current

Stratigraphic framework of the late Miocene to Pliocene Pisco Formation at Cerro Colorado (Ica Desert, Peru)

This paper describes a 200 m-thick section of the Pisco Formation exposed at Cerro Colorado, an important fossiliferous site in the Ica desert. In order to properly place the fauna in its correct relative position, this study establishes the stratigraphic framework within which the different fossil-bearing intervals of this site can be compared and may prove invaluable in future high-resolution studies on the faunal change. Most of the Pisco Formation deposits exposed at Cerro Colorado consist of gently dipping fine-grained sandstones, diatomaceous siltstones and diatomites with minor ash layers and dolomites deposited within nearshore and offshore settings. To facilitate detailed stratigraphic correlations within the Pisco strata for a 30 km2 area, eight marker beds have been defined and large-scale (1:10,000 scale) geological mapping conducted to determine fault positions, styles and offsets. The geological map shows that there are two important angular unconformities in the study area. The first one is the interformational basal unconformity of the Pisco Formation against folded, faulted, and planated Oligo-Miocene rocks of the Chilcatay Formation. The second is a low-angle intraformational erosional discontinuity of up to 48 angular discordance that allows the subdivision of the Pisco stratigraphy exposed in the study area into two informal allomembers. Dating of the exposed succession by diatom biostratigraphy suggests that the age of the lower allomember is late Miocene, whereas the upper allomember is late Miocene or younger

Direct oral anticoagulants for secondary prevention in patients with non-valvular atrial fibrillation

The patients with non-valvular atrial fibrillation (NVAF), both permanent and paroxysmal, and history of previous transient ischemic attack (TIA) or stroke represent a category of patients at high risk of new embolic events, independently of the presence of other risk factors. In these patients, national and international guidelines recommend oral anticoagulants as first choice for antithrombotic prevention. Direct oral anticoagulants (DOACs) have been demonstrated to be not inferior to warfarin for many end points in NVAF patients in terms of efficacy and safety. The post hoc analysis in selected subgroups of patients enrolled in the three mega trials of phase III comparing DOACs (RE-LY, ROCKET-AF and ARISTOTLE) with warfarin help to evaluate whether superiority and non-inferiority persist in these subgroups. Here, patients with NVAF and history of previous TIA/stroke receiving DOACs as secondary prevention are compared with patients with the same characteristics receiving warfarin. An analysis of these patients has been recently published (separately for each of three DOACs). This analysis shows that DOACs maintain their non-inferiority when compared with warfarin in secondary prevention, representing a real alternative in this context of patients at high risk for ischemic and bleeding events