305,181 research outputs found
Ipnosi come "stato modificato di coscienza": un ponte tra ricerca sperimentale e prassi psicoterapeutica (seconda parte)
No full textSlope fans and aprons dominated by supercritical bedforms: topographic and feeding system controls (Southeastern Tyrrhenian Sea)
No full textIn the marine environment, turbidite supercritical bedforms have been widely reported from channel-axis and overbank wedges. On the contrary, their dominance in the make-up of fans and apron, apart from local areas such as channel mouths, is at present not recognized. However, since it has been postulated that turbidity currents reach the supercritical conditions for slope > 0.5°, submarine slopes should contain abundant supercritical flow deposits. Here, we provide a review of different types of slope fans and aprons dominated by supercritical bedforms, based on examples from the modern seafloor. We compare depositional elements located in different intraslope basins of the Tyrrhenian Sea, through high-resolution bathymetry, chirp subbottom section and, where available cores. The variable geological context results in axial and transvers slope fans with highly variable sizes (few to tens of kilometres) and geometries, dependent upon the erosive and/or depositional processes involved, as well as the seafloor topography of the area. In particular, we have recognized two types of lobe-shaped deposits characterized by supercritical bedforms: channel-attached fans and detached aprons. The first ones are connected to a canyon-channel system and develop on slope gradients of 0.5° to 1.2°, display small-scale bedforms (wavelength of about 150 m and height < 10 m), with upslope asymmetric or symmetric cross-sections, interpreted as cyclic steps and antidunes. According to the amplitude of the reflections, cores, and to the bedform aspect ratio, the channel-attached fans are interpreted to be composed of coarse-grained sediments. Our examples highlight that cyclic steps and antidunes dominate the channel-attached fans both in axial and lateral portion while scours mark topographic changes such as breaks in slope or laterally confined areas. Detached aprons develop from the un-incised shelf edge on steep slopes of about 1.2° to 3° and are composed by large-scale bedforms (wavelength of about 500 m and height of about 5 m) mainly upslope asymmetric, associated with cyclic steps. The low amplitude of the seismic reflections suggests the fine-grained nature of the aprons. This study shows that there are significant differences in the distribution and character of supercritical bedforms in slope settings according to the type of feeding system, the degree of flow confinement and the seafloor topography. The analysis of the downslope evolution of turbidity currents, and of the character of associated bedforms in deep-water systems can contribute new perspectives to refine our models of deep-sea depositions
Ipnosi come "stato modificato di coscienza": un ponte tra ricerca sperimentale e prassi psicoterapeutica. Prima parte
No full textDownslope evolution of supercritical bedforms in a confined deep-sea fan lobe, Amantea Fan, Paola Basin (Southeastern Tyrrhenian Sea)
No full textThe sedimentology of upper flow regime bedforms represents an important research topic at the present. Deposits interpreted as those of supercritical flows are widely recognized in modern fan systems, but their recovery is challenging. Most of the sedimentological information has come from channel thalwegs but supercritical bedforms are also frequently downslope from the channel mouths. Such an environment has been identified in the Paola basin, where erosive and depositional cyclic steps have been imaged and identified in a sandy submarine lobe of the Amantea Fan. High-resolution sub-bottom profiles provide insight into the bedform internal architecture and their relationships with a frontally-confining ridge. For the first time, supercritical bedforms in a submarine lobe have been interpreted in two distinct positions: in the scour of an erosional cyclic step and in the stoss side of a depositional cyclic step. Coarse to medium-grained massive sand with flame structures, indicating rapid sediment fall-out and frequently associated with the occurrence of hydraulic jumps, has been identified in the scour and at the toe of the ridge. The latter represents an example of topographically induced hydraulic jumps driven by a frontal confinement. Top-cut-out medium to fine sands with tractive structures have been interpreted as the deposits related to the stoss side of a cyclic step or small-scale antidune superimposed on the cyclic step surface. The presented data broaden the understanding of the range of processes that are driven by the interaction between turbidity currents and seafloor topography and the dip of the slope. The recognition that topography influences the density structure and the degree of criticality of the flow and, consequently, the morphodynamics and facies of the relative deposits may help to explain sediment distribution and improve depositional models of fan lobes in confined settings
Downslope evolution of supercritical bedforms in a confined deep-sea fan lobe, Amantea Fan, Paola Basin (Southeastern Tyrrhenian Sea)
No full textThe sedimentology of upper flow regime bedforms represents an important research topic at the present. Deposits interpreted as those of supercritical flows are widely recognized in modern fan systems, but their recovery is challenging. Most of the sedimentological information has come from channel thalwegs but supercritical bedforms are also frequently downslope from the channel mouths. Such an environment has been identified in the Paola basin, where erosive and depositional cyclic steps have been imaged and identified in a sandy submarine lobe of the Amantea Fan. High-resolution sub-bottom profiles provide insight into the bedform internal architecture and their relationships with a frontally-confining ridge. For the first time, supercritical bedforms in a submarine lobe have been interpreted in two distinct positions: in the scour of an erosional cyclic step and in the stoss side of a depositional cyclic step. Coarse to medium-grained massive sand with flame structures, indicating rapid sediment fall-out and frequently associated with the occurrence of hydraulic jumps, has been identified in the scour and at the toe of the ridge. The latter represents an example of topographically induced hydraulic jumps driven by a frontal confinement. Top-cut-out medium to fine sands with tractive structures have been interpreted as the deposits related to the stoss side of a cyclic step or small-scale antidune superimposed on the cyclic step surface. The presented data broaden the understanding of the range of processes that are driven by the interaction between turbidity currents and seafloor topography and the dip of the slope. The recognition that topography influences the density structure and the degree of criticality of the flow and, consequently, the morphodynamics and facies of the relative deposits may help to explain sediment distribution and improve depositional models of fan lobes in confined settings
Analysis of Factors Affecting E-Supply Chain Performances
No full textThe relevance of supply chain management (SCM) is continuously increasing, especially with respect to companies adopting e-commerce strategies. Although the huge number of works on this topic, an integrated approach to design and implement effective electronic supply chain (e-SC) – that is supply chain (SC) in which business actors are connected via Internet technologies - is still not available. In order to contribute towards the definition of this comprehensive framework, in this paper variables influencing e-SC performances are investigated and correlated
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Analysis of Factors Affecting E-supply Chain Performances
No full textThe relevance of supply chain (SC) behaviour is continuously increasing, especially with respect to companies adopting e-commerce strategies. Although the huge number of research on this topic, an integrated, approach to design and implement effective electronic supply chain (e-SC) is not still available. In order to define basis for a definition of an integrated approach for e-SC analysis and design, in this paper different set of variables which influence its performance are investigated, including organization, management and control
Distribución del ingreso familiar y estado nutricional en niños de 6-24 meses que asisten a los controles de PMI de los Centros de Atención Primaria 9 de Julio y APAND
No full textEl presente estudio tiene como objetivo determinar la relación entre la distribución de los ingresos familiares destinado a la compra de los diferentes grupos de alimentos en el hogar, y el estado nutricional de los niños de 6-24 meses que asisten a los controles de PMI en los centros de atención primaria de la salud APAND y 9 de Julio, de la ciudad de Mar del Plata.
A través del mismo se realiza una evaluación del estado nutricional de los niños mediante los indicadores antropométricos de peso para la edad (P/E), longitud corporal para la edad (LC/E), y peso para la longitud corporal (P/LC), a partir de datos recolectados mediante una encuesta dirigida a las madres/padres/tutores de los niños, y el acceso a las historias clínicas. Al mismo tiempo se indaga sobre la recepción de planes de asistencia alimentaria y el ingreso mensual de cada uno de los hogares, para poder identificar la población bajo la línea de pobreza y estimar el porcentaje del ingreso mensual del hogar destinado a la alimentación en general, y por grupos de alimentos. Para la estimación de éstos últimos datos, se utiliza, además, una frecuencia de compra que permite registrar los alimentos y cantidades compradas el último mes, con la posterior investigación de los
precios de los alimentos en el comercio mas referido por las madres/padres/tutores en la encuesta.Fil: Scacchia, Sergio. Universidad FASTA. Facultad de Ciencias Médicas; Argentina.Fil: Bellino, Natalia. Universidad FASTA. Facultad de Ciencias Médicas; Argentina
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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