This basin was situated along the active margin of a Paleozoic foreland basin in western Pexidartinib order Gondwana. Continuous sedimentation occurred in different paleoenvironments from east to west: marginal marine settings with estuarine and deltaic deposits (Sierras Subandinas), shallow marine shelf environments with large clastic deposits in the central part (Cordillera Oriental-eastern Puna), and deep marine deposits with volcaniclastic supplies (western Puna). Limited biostratigraphic and chronostratigraphic data from these sequences are known from graptolites, conodonts and trilobites, and more recently also from palynomorphs. An analysis of Ordovician

sections from the different sedimentological settings of northwestern Argentina produced 60 chitinozoan-bearing samples from which 19 genera and 45 species have been recorded. Four chitinozoan assemblages were observed in the Lower Ordovician from northwestern Argentina. Correlations with other fossil groups provide independent biostratigraphic selleck control. A stratigraphic range chart of selected acritarch taxa throughout the Ordovician of the Central Andean Basin is developed and biostratigrapic or potential biostratigraphic markers for the basin

are proposed. In northwestern Argentina, Late Ordovician chitinozoan assemblages display affinities with Polar to Subpolar faunas. (C) 2012 Elsevier B.V. All rights reserved.”
“Objective. The aim of this study

was to evaluate the reinforcing effect of differently oriented fibers on the load-bearing capacity of three-unit fixed dental prostheses BMN 673 order (FDPs). Materials and methods. Forty-eight composite FDPs were fabricated. Specimens were divided into eight groups (n = 6/group; codes 1-8). Groups 1 and 5 were plain restorative composites (Grandio and Z100) without fiber reinforcement, groups 2 and 6 were reinforced with a continuous unidirectional fiber substructure, groups 3 and 7 were reinforced with a continuous bidirectional fiber and groups 4 and 8 were reinforced with a continuous bidirectional fiber substructure and continuous unidirectional fiber. FDPs were polymerized incrementally with a handheld light curing unit for 40 s and statically loaded until final fracture. Results. Kruskal-Wallis analysis revealed that all groups had significantly different load-bearing capacities. Group 4 showed the highest mean load-bearing capacity and Group 7 the lowest. Conclusion. The results of this study suggest that continuous unidirectional fiber increased the mechanical properties of composite FDPs and bidirectional reinforcement slowed crack propagation on abutments.”
“Fe3O4 is one of the important oxide materials and its surface structure should be well understood to enable application of this material. We report the first noncontact atomic force microscopy (NC-AFM) results for Fe3O4(001) thin films.