62 research outputs found

    Lamniform shark teeth from the Late Cretaceous of southernmost South America (Santa Cruz Province, Argentina)

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    Here we report multiple lamniform shark teeth recovered from fluvial sediments in the (Campanian-Maastrichtian) Cerro Fortaleza Formation, Santa Cruz Province, Argentina. This small tooth assemblage is compared to various lamniform sharks possessing similar dental morphologies, including Archaeolamna, Cretalamna, Dwardius, Dallasiella, and Cretodus. Although the teeth share numerous morphological features with the genus Archaeolamna, including a developed neck that maintains a relatively consistent width along the base of the crown, the small sample size and incomplete nature of these specimens precludes definitive taxonomic assignment. Regardless, the discovery of selachian teeth unique from those previously described for the region broadens the known diversity of Late Cretaceous South American sharks. Additionally, the discovery of the teeth in fluvial sandstone may indicate a euryhaline paleobiology in the lamniform taxon or taxa represented by this tooth assemblage.Fil: Schroeter, Elena R.. Drexel University; Estados UnidosFil: Egerton, Victoria M.. University Of Manchester; Reino UnidoFil: Ibiricu, Lucio Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Lacovara, Kenneth J.. Drexel University; Estados Unido

    Microstratigraphic Analysis of Fossil Distribution in the Lower Hornerstown and Upper Navesink Formations at the Edelman Fossil Park, NJ

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    Maastrichtian–Danian sediments of the Navesink and Hornerstown formations at the Jean and Ric Edelman Fossil Park of Rowan University in Mantua Township, New Jersey, have long intrigued paleontologists. Within the basal Hornerstown Formation occurs the Main Fossiliferous Layer (MFL), a regionally well-known and diverse bonebed. The lithostratigraphic and chronostratigraphic position of this fossil layer have been debated for more than 50 years, fueling debate over its origin. Herein, we present the results of a microstratigraphic analysis of the fossil composition and distribution of the MFL undertaken to rectify these discrepancies. Through methodical top-down excavation, we recorded the three-dimensional position of every fossil encountered. Three-dimensional visualization and analyses of these data in ArcGIS Pro yielded an unprecedented view of this bonebed. Most reported discrepancies about the stratigraphic placement and thickness of the MFL can be explained by the presence of two distinct fossil assemblages within this interval that are occasionally combined into a single bonebed. The stratigraphically-lower assemblage, herein termed an “oyster layer”, is geometrically-tabular and exhibits low taxonomic diversity, high abundance of the oyster Pycnodonte, and moderate taxonomic richness. The stratigraphically-higher assemblage, the MFL, occurs approximately 9 cm higher in section and exhibits high values of taxonomic diversity, fossil abundance, and taxonomic richness. Sedimentological homogeneity throughout this interval suggests that these faunal contrasts arise from the two assemblages having formed via independent taphonomic pathways. Specifically, prevalence of Pycnodonte in the oyster layer implies formation by a selective mortality event, whereas the diversity of the MFL appears to reflect a more universal agent of mortality. Spatial variations in the stratigraphic distribution of fossils within the MFL in our excavation area indicate this assemblage does not form a simple, tabular layer as previously thought and may, in part, record original bathymetry. Importantly, our definition of the MFL and detailed characterization of its stratigraphic placement are essential for future studies on the taphonomic origin and chronostratigraphy of this bonebed. Universal use of this definition would allow researchers to confidently elucidate the exact lithostratigraphic positions of precise chronostratigraphic indicators within the MFL and accurately estimate the degree of time averaging of its fossils

    Incidencias en Trichostrongylídeos en relación con los patrones de remolinos frontales en bovinos

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    La transmisión de los nematodes gastrointestinales trichostrongylideos de los rumiantes en pastoreo está asociada con la ingestión de sus larvas infectivas distribuidas en las pasturas. Con el objetivo de analizar si la incidencia de estas parasitosis en bovinos podría estar influenciada por la posición de los remolinos pilosos de la cabeza, fueron evaluadas las intensidades medias e Intervalos de confianza 95 % de los recuentos de huevos de nematodes por gramo de materia fecal (hpg) de 126 muestras pertenecientes a tres rodeos de bovinos Aberdeen Angus de 8 a 10 meses de edad. Los valores hallados para los animales con remolinos-altos fueron de 203.7 (155.6-259.3), 300.1 (200-440.1) y 360 (200-520), para animales con los remolinos-medios de 253.4 (173.3-360.1), 417 (216.6-600.7) y 416.7 (341.67-500) y para los animales con remolinos-bajos de 250 (186.4-318.2), 362.8 (212.5-525.5) y 433.6 (350.06-522.6) en los rodeos denominados Villegas, Zavalla y Tierra. En los tres rodeos, los bovinos con remolinos medios y bajos presentaron tendencias mayores en sus incidencias medias, mientras que en los animales con remolinos pilosos altos, las incidencias medias tendieron a ser más bajas. Otros factores, además del comportamiento, pueden influir en las intensidades del parasitismo por nematodes trichostrongylideos según los tipos de remolinos. Entender las diferencias probablemente esté asociado a explicar cómo se conforma el estilo de pastoreo en los grupos de animales en relación a cada subtipo en la zona de ingesta.Transmission of gastrointestinal nematodes from grazing ruminants is associated with the ingestion of their infective larvae distributed in pastures. In order to analyze if the incidence of parasitism in cattle could be influenced by associated to hair whorl position of the head, the mean intensities and 95% confidence intervals of nematode egg counts were evaluated by gram of fecal material (epg) of 126 samples cattle of 8 to 10 months old in three ranchs of Aberdeen Angus. The values were for animals with high whorl 203.7 (155.6-259.3), 300.1 (200-440.1) and 360 (200-520), for animals with middle whorl 253.4 (173.3-360.1), 417 (216.6)-600.7) and 416.7 (341.67-500), and for animals with low whorl 250 (186.4-318.2), 362.8 (212.5-525.5) and 433.6 (350.06-522.6) in the herds Villegas, Zavalla and Tierra. In the three rodeos, the animals with medium and low whorl presented higher trends in their mean incidences, while in animals with high hair whorl, the average incidences tended to be lower. Other factors, besides behavior, can influence the intensities of parasitism by trichostrongylid nematodes according to the types of swirls. Understanding the differences is probably associated with explaining how the grazing style is conformed in the groups of animals in relation to each subtype in the intake zone.EEA General VillegasFil: Ardusso, Gerardo L. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: Lacovara, Martin Andres. Becario INTA-AUDEAS CONADEV; ArgentinaFil: Graziati, Georgina. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: Angulo Lewille, M. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: Kleinerman, Gabriela. The Hebrew University of Jerusalem. Koret School of Veterinary Medicine; IsraelFil: Buffarini, Miguel. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria General Villegas; ArgentinaFil: Giudici, Claudio. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    A basal lithostrotian titanosaur (Dinosauria: Sauropoda) with a complete skull: Implications for the evolution and paleobiology of titanosauria

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    We describe Sarmientosaurus musacchioi gen. et sp. nov., a titanosaurian sauropod dinosaur from the Upper Cretaceous (Cenomanian - Turonian) Lower Member of the Bajo Barreal Formation of southern Chubut Province in central Patagonia, Argentina. The holotypic and only known specimen consists of an articulated, virtually complete skull and part of the cranial and middle cervical series. Sarmientosaurus exhibits the following distinctive features that we interpret as autapomorphies: (1) maximum diameter of orbit nearly 40% rostrocaudal length of cranium; (2) complex maxilla - lacrimal articulation, in which the lacrimal clasps the ascending ramus of the maxilla; (3) medial edge of caudal sector of maxillary ascending ramus bordering bony nasal aperture with low but distinct ridge; (4) ´tongue-like´ ventral process of quadratojugal that overlaps quadrate caudally; (5) separate foramina for all three branches of the trigeminal nerve; (6) absence of median venous canal connecting infundibular region to ventral part of brainstem; (7) subvertical premaxillary, procumbent maxillary, and recumbent dentary teeth; (8) cervical vertebrae with ´strut-like´ centroprezygapophyseal laminae; (9) extremely elongate and slender ossified tendon positioned ventrolateral to cervical vertebrae and ribs. The cranial endocast of Sarmientosaurus preserves some of the most complete information obtained to date regarding the brain and sensory systems of sauropods. Phylogenetic analysis recovers the new taxon as a basal member of Lithostrotia, as the most plesiomorphic titanosaurian to be preserved with a complete skull. Sarmientosaurus provides a wealth of new cranial evidence that reaffirms the close relationship of titanosaurs to Brachiosauridae. Moreover, the presence of the relatively derived lithostrotian Tapuiasaurus in Aptian deposits indicates that the new Patagonian genus represents a ´ghost lineage´ with a comparatively plesiomorphic craniodental form, the evolutionary history of which is missing for at least 13 million years of the Cretaceous. The skull anatomy of Sarmientosaurus suggests that multiple titanosaurian species with dissimilar cranial structures coexisted in the early Late Cretaceous of southern South America. Furthermore, the new taxon possesses a number of distinctive morphologies - such as the ossified cervical tendon, extremely pneumatized cervical vertebrae, and a habitually downward- facing snout - that have rarely, if ever, been documented in other titanosaurs, thus broadening our understanding of the anatomical diversity of this remarkable sauropod clade. The latter two features were convergently acquired by at least one penecontemporaneous diplodocoid, and may represent mutual specializations for consuming low-growing vegetation.Fil: Martínez, Rubén Darío. Universidad Nacional de la Patagonia; ArgentinaFil: Lamanna, Matthew C.. Carnegie Museum Of Natural History; Estados UnidosFil: Novas, Fernando Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "bernardino Rivadavia"; ArgentinaFil: Ridgely, Ryan C.. Ohio University College Of Osteopathic Medicine; Estados UnidosFil: Casal, Gabriel. Universidad Nacional de la Patagonia; ArgentinaFil: Martínez, Javier E.. Hospital Regional de Comodoro Rivadavia; ArgentinaFil: Vita, Javier R.. Resonancia Magnética Borelli; ArgentinaFil: Witmer, Lawrence M.. Ohio University College Of Osteopathic Medicine; Estados Unido

    How does disaggregating a pooled inventory affect a Marine Aircraft Group?

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    MBA Professional ReportIn 2013, Marine Aircraft Group 11 (MAG-11) directed Marine Aviation Logistics Squadron 11 (MALS-11) to move Marine Fighter Attack Training Squadron 101’s (VMFAT-101) inventory allowances from MALS-11’s warehouses to VMFAT-101’s squadron spaces. The intent of this policy was to decrease requisition delivery time and increase VMFAT-101’s aircraft readiness. In only one month, MALS-11 staged the appropriate inventory at the squadron along with a detachment of Marines to manage the material. We review the effects of the inventory move on MAG-11 as a whole, in terms of order lead time and capacity utilization. In addition, we examine the new inventory policy’s other effects, such as workflow efficiency.http://archive.org/details/howdoesdisaggreg1094544621Captain, United States Marine CorpsApproved for public release; distribution is unlimited

    The first record of a neonatal ornithopod dinosaur from Gondwana

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    Discrete post-embryonic teeth and bone fragments have been recovered from the matrix with the holotype skeleton (MPM‐10001) of the ornithopod dinosaur, Talenkauen santacrucensis Novas et al., 2004 (Upper Cretaceous, Argentina). The minute tooth crowns are 1 mmapicobasally tall and 1.7 mmmesodistally wide. The crowns are symmetrical and have a centrally located primary ridge on the lingual surface. Secondary ridges lead to five marginal denticles on both teeth. The tooth morphology is consistent with dentary teeth in euiguanodontids. There is no evidence of transport, suggesting that the material is autochthonous with respect to the adult body block of T. santacrucensis (MPM‐10001). Steeply inclined wear facets on the lingual surface and associated microstriae support the conclusion that the minute teeth were from a post-embryonic euiguanodontid dinosaur rather than early stage replacement teeth. The morphology, size, and wear of the teeth and small bone fragments found in the body block ofMPM‐10001 suggest that this material belongs to a neonatal T. santacrucensis. This is the first record of neonatal ornithopod remains from Gondwana.Fil: Egerton, Victoria M. . Drexel University; Estados Unidos. University Of Manchester; Reino UnidoFil: Novas, Fernando Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: Dodson, Peter. State University Of Pennsylvania; Estados UnidosFil: Lacovara, Kenneth. Drexel University; Estados Unido

    Incidencias en trichostrongylídeos en relación con los patrones de remolinos frontales en bovinos

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    Transmission of gastrointestinal nematodes from grazing ruminants is associated with the ingestion of their infective larvae distributed in pastures. In order to analyze if the incidence of parasitism in cattle could be influenced by associated to hair whorl position of the head, the mean intensities and 95% confidence intervals of nematode egg counts were evaluated by gram of fecal material (epg) of 126 samples cattle of 8 to 10 months old in three ranchs of Aberdeen Angus. The values were for animals with high whorl 203.7 (155.6-259.3), 300.1 (200-440.1) and 360 (200-520), for animals with middle whorl 253.4 (173.3-360.1), 417 (216.6)-600.7) and 416.7 (341.67-500), and for animals with low whorl 250 (186.4-318.2), 362.8 (212.5-525.5) and 433.6 (350.06-522.6) in the herds Villegas, Zavalla and Tierra. In the three rodeos, the animals with medium and low whorl presented higher trends in their mean incidences, while in animals with high hair whorl, the average incidences tended to be lower. Other factors, besides behavior, can influence the intensities of parasitism by trichostrongylid nematodes according to the types of swirls. Understanding the differences is probably associated with explaining how the grazing style is conformed in the groups of animals in relation to each subtype in the intake zone.Fil: Ardusso, G.L. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Enfermedades Parasitarias. Santa Fe, ArgentinaFil: Lacovara, M. Instituto Nacional de Tecnología Agropecuaria (INTA). AUDEAS CONADEV. ArgentinaFil: Graziati, G. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Patología Médica. Santa Fe, ArgentinaFil: Angulo Lewille, M. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Patología Médica. Santa Fe, ArgentinaFil: Kleinerman, G. The Hebrew University of Jerusalem. Koret School of Veterinary Medicine. Jerusalem, IsraelFil: Buffarini, M. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria General Villegas (EEA). Buenos Aires, ArgentinaFil: Giudici, C. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Enfermedades Parasitarias. Santa Fe, ArgentinaFil: Giudici, C. Universidad Nacional de Rosario. Consejo de Investigaciones. Santa Fe, ArgentinaLa transmisión de los nematodes gastrointestinales trichostrongylideos de los rumiantes en pastoreo está asociada con la ingestión de sus larvas infectivas distribuidas en las pasturas. Con el objetivo de analizar si la incidencia de estas parasitosis en bovinos podría estar influenciada por la posición de los remolinos pilosos de la cabeza, fueron evaluadas las intensidades medias e Intervalos de confianza 95 % de los recuentos de huevos de nematodes por gramo de materia fecal (hpg) de 126 muestras pertenecientes a tres rodeos de bovinos Aberdeen Angus de 8 a 10 meses de edad. Los valores hallados para los animales con remolinos-altos fueron de 203.7 (155.6-259.3), 300.1 (200-440.1) y 360 (200-520), para animales con los remolinos-medios de 253.4 (173.3-360.1), 417 (216.6-600.7) y 416.7 (341.67-500) y para los animales con remolinos-bajos de 250 (186.4- 318.2), 362.8 (212.5-525.5) y 433.6 (350.06-522.6) en los rodeos denominados Villegas, Zavalla y Tierra. En los tres rodeos, los bovinos con remolinos medios y bajos presentaron tendencias mayores en sus incidencias medias, mientras que en los animales con remolinos pilosos altos, las incidencias medias tendieron a ser más bajas. Otros factores, además del comportamiento, pueden influir en las intensidades del parasitismo por nematodes trichostrongylideos según los tipos de remolinos. Entender las diferencias probablemente esté asociado a explicar cómo se conforma el estilo de pastoreo en los grupos de animales en relación a cada subtipo en la zona de ingesta
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