175 research outputs found
Evaluación del analizador Glucocard Memory 2 para medir la concentración de glucosa en sangre capilar
ObjetivoEvaluar la validez y precisión analítica y la practicabilidad del sistema medidor de la concentración de glucosa Glucocard Memory 2 diseñado para el autocontrol del paciente diabético.DiseñoDescriptivo, transversal. Validación de un instrumento de medida siguiendo las recomendaciones de la Sociedad Española de Bioquímica Clínica y Patología Molecular.!EmplazamientoEstudio realizado en un laboratorio de atención primaria.MuestraNoventa y tres muestras de sangre de pacientes diabéticos seleccionadas mediante muestreo consecutivo de los tubos recibidos en el laboratorio para realizar el protocolo analítico de seguimiento de diabetes.Mediciones y resultados principalesLa repetibilidad del sistema se estudió analizando la precisión intradía a 4 concentraciones distintas de glucosa, obteniéndose coeficientes de variación entre el 2,12% (a 410 mg/dl de glucosa) y un 4,17% (a 37,2 mg/dl). La linealidad del analizador se demostró experimentalmente entre 27 y 485 mg/dl. La exactitud se evaluó por comparación con el procedimiento habitual del laboratorio (Hitachi 747, GOD-PAP), calculando la recta de regresión mediante el método de Passing-Bablok (y = 1,01, × –2,34) y mediante la obtención del coeficiente de correlación intraclase, cuyo resultado fue del 99%. La técnica de análisis de «error Grid» para investigar la significación clínica de las posibles desviaciones respecto al método de referencia dio un 100% de resultados dentro de la zona de exactitud clínica. El estudio de la practicabilidad mostró una gran simplicidad de manejo.ConclusionesEl Glucocard Memory 2 es un analizador para la medición de la glucemia capilar y venosa con una extrema simplicidad de manejo y unas excelentes características analíticas.ObjectiveTo evaluate the analytical reliability and accuracy as well as the practicability of the Glucocard Memory 2 glucose meter, intended to the control of the diabetic patient.DesignDescriptive, crossover study. To validate an analytical instrument according to guidelines of the Spanish Society of Clinical Biochemistry and Molecular Pathology.SettingPrimary health care, urban setting.ParticipantsNinety-three blood samples from diabetic patients were used. These samples were selected by a consecutive sampling of the tubes received in the laboratory for the diabetes follow-up protocol.Measurements and main resultsRepeatability of the system was studied analysing the within-run precision at four concentrations of glucose.We obtained coefficients of variation between 2.12% (at 410 mg/dl of glucose) and 4.17% (at 37.2 mg/dl). The linearity study allowed to check experimentally the linear response of the instrument between 27 and 485 mg/dl. The accuracy was evaluated comparing the Glucocard results with the routine procedure of our laboratory (Hitachi 747, GOD-PAP) and calculating the regression parameters with the Passing and Bablok method (y = 1,01 × –2,34) and the intraclass correlation (99%). To evaluate the clinical significance of possible deviations related with the reference laboratory method the «error Grid» analysis was used. This analysis showed that 100% of Glucocard Memory 2 results fell into the clinical accuracy zone. Practicability study showed that the instrument is very simple to use.ConclusionsGlucocard Memory 2 is a glucose meter intended to the measurement of glucose both on capillary and venous blood that, besides its extreme simplicity of use, shows very good analytical features
Activation of stylolites as conduits for overpressured fluid flow in dolomitized platform carbonates
This research was developed with funding provided by the Spanish Government I+D+I Research Projects CGL2015-69805-P and CGL2015-66335-C2-1-R, and the Generalitat de Catalunya (2014SGR251). The research also benefited from a grant of the Geological Society of London (Elspeth Matthews Fund 2015) to EGR. The authors would like to thank M. Aston and O. P. Wennberg for the editorial work, and F. Laponi and an anonymous reviewer for their critical and constructive comments.Peer reviewedPostprin
Marine and Transitional Middle/Upper Eocene Units of the Southeastern Pyrenean Foreland Basin (NE Spain)
The stratigraphic basis of this work has allowed the use of larger foraminifers in the biostratigraphic characterisation of the new Shallow Benthic Zones (SBZ). This part of the volume presents a description of the sedimentary cycles formed by the transgressive-regressive systems of the Lutetian and Bartonian in the southeastern sector of the Ebro Foreland Basin.Concerning the Lutetian deposits studied in the Amer-Vic and Empordà areas, four sedimentary cycles have been characterised. The first and second are found within the Tavertet/Girona Limestone Formation (Reguant,1967;Pallí,1972), while the third and fourth cycles cover the Coll de Malla Marl Formation (Clavell et al.,1970), the Bracons Formation (Gich,1969,1972), the Banyoles Marl Formation (Almela and Ríos,1943),and the Bellmunt Formation (Gich,1969,1972). In the Bartonian deposits studied in the Igualada area,two transgressive-regressive sedimentary cycles have been characterised in the Collbàs Formation (Ferrer,1971),the Igualada Formation (Ferrer,1971),and the Tossa Formation (Ferrer,1971). The Shallow Benthic Zones (SBZs)recognised within the Lutetian are the following:SBZ 13, from the Early Lutetian, in the transgressive system of the first cycle;SBZ 14,from the Middle Lutetian, in the second cycle and the lower part of the transgressive system of the third cycle; SBZ 15,from the Middle Lutetian, in the remaining parts of the third system; SBZ 16, from the Late Lutetian,throughout the fourth cycle.The association of larger foraminifers in the first and second cycles of the Bartonian in the Igualada area has been used as the basis for the definition of SBZs 17 and 18 recognised in the Bartonian of the western Tethys
Permian-Triassic red-stained albitized profiles in the granitic basement of the NE Spain: evidence for deep alteration related to the Triassic Palaeosurface
Extensive areas of the Variscan granitic basement in NE Spain display profiles of red-stained albitized facies characterized by albitization of Ca-plagioclase, chloritization of biotite and microclinization of orthoclase, along with the alteration of igneous quartz to secondary CL-dark quartz. These profiles have a geopetal structure beneath the Triassic unconformity, with a very intense and pervasive alteration in the upper part that progressively decreases with depth to 150-200 m where the alteration is restricted to the walls of fractures. The red albitized facies contains secondary maghemite and hematite that indicate oxidizing conditions. Dating of microclinized orthoclase and secondary monazite that have formed in the red-stained albitized facies yielded K-Ar and U-Th-Pbtotal ages of 240 and 250 Ma, respectively, suggesting that the alteration developed during the Permian-Triassic period. The geopetal disposition of the red albitized profile with respect to the Triassic unconformity, its large regional extent, and the fracture-controlled alteration in the lower part of the profile indicate groundwater interaction. The δ18O values of albitized plagioclase (+ 11¿), microclinized orthoclase (+ 13¿), and secondary CL-dark quartz (+ 12¿) suggest that the alteration temperature was about 55 °C. This 'low' temperature suggests that the alteration occurred during interaction of the granitic rocks with Na-rich fluids below a surficial weathering mantle on the Permian-Triassic palaeosurface. The latter is possibly related to Triassic evaporitic environments in long-lasting, stable landscapes in which Na-rich solutions infiltrated deep regional groundwaters
BCN Rocks: aprendiendo geología urbana a través de una aplicación App interactiva
BCN Rocks is an application (App) for personal mobile devices (Android and iOS versions) suitable for secondary and high school students as well as people without background in Earth Sciences. The main objective of this App is to learn geology using the city facades and pavements of two emblematic spaces of the city of Barcelona, the Passeig de Gràcia and the Barri Gòtic. The application has three main sections (ELEMENTS, EXPLORE, and LABORATORY) that are intended to satisfy the different needs of users. In the first section, Elements, the user will find all the information about rocks forming the selected buildings as well as a brief explanation about the history and architecture of each edifice. The second section, Explore, aims to arise the curiosity of users. In this sense, several routes are proposed according to different criteria including geographic position and age of the edifices. Finally, the third section, Laboratory, allows all users to investigate several geological aspects by means of interactive experiments.Este trabajo se enmarca en un proyecto financiado por la Fundación Española para la Ciencia y la Tecnología, FECYT (ref. 8524) en el que ha participado la Universitat de Barcelona, el Instituto de Ciencias de la Tierra Jaume Almera del Consejo Superior de Investigaciones Científicas (ICTJA-CSIC) y la empresa FUSTA. AG agradece su contrato Ramón y Cajal (RYC-2012-11024).Peer Reviewe
Marine and Transitional Middle/Upper Eocene Units of the Southeastern Pyrenean Foreland Basin (NE spain)
The stratigraphic basis of this work has allowed the use of larger foraminifers in the biostratigraphic characterisation of the new Shallow Benthic Zones (SBZ). This part of the volume presents a description of the sedimentary cycles formed by the transgressive-regressive systems of the Lutetian and Bartonian in the southeastern sector of the Ebro Foreland Basin.Concerning the Lutetian deposits studied in the Amer-Vic and Empordà areas, four sedimentary cycles have been characterised. The first and second are found within the Tavertet/Girona Limestone Formation (Reguant,1967;Pallí,1972), while the third and fourth cycles cover the Coll de Malla Marl Formation (Clavell et al.,1970), the Bracons Formation (Gich,1969,1972), the Banyoles Marl Formation (Almela and Ríos,1943),and the Bellmunt Formation (Gich,1969,1972). In the Bartonian deposits studied in the Igualada area,two transgressive-regressive sedimentary cycles have been characterised in the Collbàs Formation (Ferrer,1971),the Igualada Formation (Ferrer,1971),and the Tossa Formation (Ferrer,1971). The Shallow Benthic Zones (SBZs)recognised within the Lutetian are the following:SBZ 13, from the Early Lutetian, in the transgressive system of the first cycle;SBZ 14,from the Middle Lutetian, in the second cycle and the lower part of the transgressive system of the third cycle; SBZ 15,from the Middle Lutetian, in the remaining parts of the third system; SBZ 16, from the Late Lutetian,throughout the fourth cycle.The association of larger foraminifers in the first and second cycles of the Bartonian in the Igualada area has been used as the basis for the definition of SBZs 17 and 18 recognised in the Bartonian of the western Tethys
Fluid-rock interaction control on fault reactivation: A review of the Montmell-Vallès Fault System, central Catalan Coastal Ranges (NE Iberia)
Structural inheritance is a key factor controlling the tectonic evolution of the central Catalan Coastal Ranges. Up to two periods of tectonic inversion (one positive during the Paleogene and the other negative during the Neogene) affected a previously well-developed Mesozoic extensional basin system and characterized the Cenozoic evolution of the area. In this scenario, tectonic fault inversion is often observed along the Montmell-Vallès Fault System. Fault reactivation shows differences along strike from NE to SW and appears decoupled from surface to depth due to its kinked-planar geometry and the change of fault dip from >60° to 30° in depth. The ability of the Mesozoic faults to be reactivated appears also influenced by changes in the mechanical properties of the inherited fault zone. Whereas the deeper and less dipping panels of the major faults are reactivated in the entire zone (contractional during the Paleogene and extensional during the late Oligocene-Neogene), the upper and highly dipping parts of the faults only show local reactivations. The observations indicate that fault dip, the indirect role of hosting lithologies (granites and siliciclastic metasediments versus carbonate rocks) on fault rocks, the indirect role of mineral precipitation and cementation product of fluid circulation, and the direct role of the mechanical properties of the resulting fault rocks (gouge versus cemented breccias) significantly control the fault reactivation. Upper crust low angle fault segments are easily reactivated during contractional deformation but not during the extensional one. Conversely, the segments with a high-angle dip are more easily reactivated during the extensional deformation but not during the contractional one. In the study area, this resulted in the formation of footwall short-cuts developed during the Paleogene compression and extensional short-cuts occurred during the Neogene extension. On the other hand, reactivation is effective in areas where granites and siliciclastic metasediments characterize the host-rock, and non-cohesive fault gouge forms the pre-existent fault core. Instead, fault reactivation appears restricted or even prevented where the host-rock includes thick carbonate successions, and the pre-existent damage zone is formed by highly cemented and cohesive breccias
Allochthonous salt advance recorded by the adjacent syn-kinematic sedimentation: Example from the Les Avellanes diapir (South Central Pyrenees)
This work aims to present the Les Avellanes diapir as a field analog to inquire how the origin, advance, and emplacement of an allochthonous salt body in continental settings influence the local sedimentation in terms of facies distribution, sediment provenance, and stratigraphic relationships. At the frontal part of the South-Central Pyrenean fold-and-thrust belt (Spain), the Les Avellanes diapir is an outcropping salt structure made of Triassic evaporites, lutites and carbonates. At the diapir's western boundary, a structurally controlled sub-basin presents a well-preserved, early Oligocene in age, mixed clastic-evaporitic sedimentary sequence which recorded the lateral extrusion of the diapir and its emplacement as an allochthonous salt sheet. To define the events and processes recorded by the adjacent sedimentary sequences, and to unravel the diapir evolution and the nature of the diapir contact at the study area, we have combined sedimentary, petrologic, and stratigraphic data. Three stratigraphic sections have been built, from which 8 lithostratigraphic facies associations have been described, interpreted, and correlated across the sub-basin. The deformation within the diapir deposit is also described and interpreted together with the sedimentary rocks. A prograding alluvial to colluvial system is associated with the piercing of the salt, which was exposed at the surface towards the NE area of the sub-basin. The dissolution of the salt resulting in the formation of a caprock with stacks of stringers of intrasalt carbonates and dolerites layers. The ongoing uplifting at the NE caused the incision of the local drainage network, marked as a paleo-relief in the stratigraphic sequence, filled by syn-kinematic breccias derived by the erosion, transport, and sedimentation of the caprock. The headward erosion reached the salt underneath the caprock, triggering the lateral extrusion. Thus, salt flowed southwards, favored by the local topography, overriding the syn-kinematic breccia deposit. Foliation and other shear-related deformation structures are observed in a megabreccia made of caprock remnants which overlap the sedimentary, syn-kinematic breccias along the base of the salt sheet deposit. These structures were probably formed during the advance of the salt sheet. The data acquired and interpreted in this work allows for the conceptualization of the relative lateral movement of a salt sheet front as recorded by adjacent syn-kinematic sedimentation in continental settings. Salt supply and erosion rates are compared with topographic slope, sedimentation, and salt dissolution as major controlling parameters of the salt sheet advance. The resulting combinations are expressed by the progradation, aggradation, and retrogradation in terms of proximal over distal facies
Use of measurement theory for operationalization and quantification of psychological constructs in systems dynamics modelling
The analytical tools available to social scientists have traditionally been adapted from tools originally designed for analysis of natural science phenomena. This article discusses the applicability of systems dynamics - a qualitative based modelling approach, as a possible analysis and simulation tool that bridges the gap between social and natural sciences. After a brief overview of the systems dynamics modelling methodology, the advantages as well as limiting factors of systems dynamics to the potential applications in the field of social sciences and human interactions are discussed. The issues arise with regards to operationalization and quantification of latent constructs at the simulation building stage of the systems dynamics methodology and measurement theory is proposed as a ready and waiting solution to the problem of dynamic model calibration, with a view of improving simulation model reliability and validity and encouraging the development of standardised, modular system dynamics models that can be used in social science research
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