68 research outputs found
Quantifying bioirrigation using ecological parameters: a stochastic approach†
Irrigation by benthic macrofauna has a major influence on the biogeochemistry and microbial community structure of sediments. Existing quantitative models of bioirrigation rely primarily on chemical, rather than ecological, information and the depth-dependence of bioirrigation intensity is either imposed or constrained through a data fitting procedure. In this study, stochastic simulations of 3D burrow networks are used to calculate mean densities, volumes and wall surface areas of burrows, as well as their variabilities, as a function of sediment depth. Burrow networks of the following model organisms are considered: the polychaete worms Nereis diversicolor and Schizocardium sp., the shrimp Callianassa subterranea, the echiuran worm Maxmuelleria lankesteri, the fiddler crabs Uca minax, U. pugnax and U. pugilator, and the mud crabs Sesarma reticulatum and Eurytium limosum. Consortia of these model organisms are then used to predict burrow networks in a shallow water carbonate sediment at Dry Tortugas, FL, and in two intertidal saltmarsh sites at Sapelo Island, GA. Solute-specific nonlocal bioirrigation coefficients are calculated from the depth-dependent burrow surface areas and the radial diffusive length scale around the burrows. Bioirrigation coefficients for sulfate obtained from network simulations, with the diffusive length scales constrained by sulfate reduction rate profiles, agree with independent estimates of bioirrigation coefficients based on pore water chemistry. Bioirrigation coefficients for O(2 )derived from the stochastic model, with the diffusion length scales constrained by O(2 )microprofiles measured at the sediment/water interface, are larger than irrigation coefficients based on vertical pore water chemical profiles. This reflects, in part, the rapid attenuation with depth of the O(2 )concentration within the burrows, which reduces the driving force for chemical transfer across the burrow walls. Correction for the depletion of O(2 )in the burrows results in closer agreement between stochastically-derived and chemically-derived irrigation coefficient profiles
Discerning natural and anthropogenic organic matter inputs to salt marsh sediments of Ria Formosa lagoon (South Portugal)
Sedimentary organic matter (OM) origin and molecular composition provide useful information to understand carbon cycling in coastal wetlands. Core sediments from threors' Contributionse transects along Ria Formosa lagoon intertidal zone were analysed using analytical pyrolysis (Py-GC/MS) to determine composition, distribution and origin of sedimentary OM. The distribution of alkyl compounds (alkanes, alkanoic acids and alkan-2-ones), polycyclic aromatic hydrocarbons (PAHs), lignin-derived methoxyphenols, linear alkylbenzenes (LABs), steranes and hopanes indicated OM inputs to the intertidal environment from natural-autochthonous and allochthonous-as well as anthropogenic. Several n-alkane geochemical indices used to assess the distribution of main OM sources (terrestrial and marine) in the sediments indicate that algal and aquatic macrophyte derived OM inputs dominated over terrigenous plant sources. The lignin-derived methoxyphenol assemblage, dominated by vinylguaiacol and vinylsyringol derivatives in all sediments, points to large OM contribution from higher plants. The spatial distributions of PAHs (polyaromatic hydrocarbons) showed that most pollution sources were mixed sources including both pyrogenic and petrogenic. Low carbon preference indexes (CPI > 1) for n-alkanes, the presence of UCM (unresolved complex mixture) and the distribution of hopanes (C-29-C-36) and steranes (C-27-C-29) suggested localized petroleum-derived hydrocarbon inputs to the core sediments. Series of LABs were found in most sediment samples also pointing to domestic sewage anthropogenic contributions to the sediment OM.EU Erasmus Mundus Joint Doctorate fellowship (FUECA, University of Cadiz, Spain)EUEuropean Commission [FP7-ENV-2011, 282845, FP7-534 ENV-2012, 308392]MINECO project INTERCARBON [CGL2016-78937-R]info:eu-repo/semantics/publishedVersio
Perception of ‘Comprehensiveness of Care’: a qualitative study amongst dentists in the Brazilian Health System
Using a Thermal Proxy to Examine Sediment–Water Exchange in Mid-Continental Shelf Sandy Sediments
Percepciones de continuidad de la atención por parte de los usuarios de los sistemas de salud en Colombia y Brasil: M Luisa Vázquez
Antecedentes La continuidad de la atención (CC) es el grado en que el paciente experimenta la atención con el tiempo como coherente y vinculada. Se identifican tres tipos de CC: relacional, informativo y gerencial. El objetivo es determinar el grado de continuidad de la atención entre la atención primaria (PC) y la atención secundaria (SC) e identificar los factores asociados en Brasil y Colombia, países con diferentes sistemas de salud. Métodos Estudio transversal mediante una encuesta de población en Brasil (Pernambuco, n = 465) y Colombia (Bogotá, n = 609) en 2011. Se analizaron los usuarios de los servicios de salud de los sistemas de salud pública de cada país. Variables de resultado: índices sintéticos en CC relacional, informativo y gerencial. Variables explicativas: características sociodemográficas y salud. Se realizaron análisis descriptivos y modelos de regresión logística multivariante. Resultados El CC relacional fue mayor en Brasil que en Colombia tanto para los médicos de PC (82.2 y 72.9%, respectivamente) como para los médicos de SC (82.4 y 70.1%, respectivamente), pero la percepción de una buena transferencia de información (CC informativo) es menor (56.3 y 67.6%, respectivamente). No se encontraron diferencias en la percepción de consistencia de la atención (CC gerencial) (alrededor del 70%). Entre los factores asociados con CC, se destacan los siguientes: en Brasil, la edad (ancianos) y el área (Caruaru, ciudad remota) se asociaron con cualquier tipo de CC. En ambos países, la mala salud autoevaluada se asoció con niveles más bajos de CC relacional y en Colombia, también, con el control clínico CC. Además, en Colombia, Conclusiones El nivel de continuidad relacional y gerencial percibida es alto, y de continuidad informativa, baja. Los factores asociados con la percepción de la continuidad de la atención difieren según el país y el tipo de continuidad de la atención. Mensajes clave Es el primer intento de evaluar los tres tipos de continuidad de la atención en áreas de Colombia y Brasil. La comprensión de los factores asociados con la continuidad de la atención revelará qué aspectos del sistema de salud pública podrían mejorarse.Background Continuity of care (CC) is the degree to which the patient experiences care over time as coherent and linked. Three types of CC are identified: relational, informational and managerial. The aim is to determine the degree of continuity of care between primary (PC) and secondary care (SC) and to identify the associated factors in Brazil and Colombia, countries with different health systems. Methods Cross-sectional study by means of a population survey in Brazil (Pernambuco, n = 465) and Colombia (Bogota, n = 609) in 2011. Users of health services of public health systems of each country were analyzed. Outcome variables: synthetic indexes on relational, informational and managerial CC. Explanatory variables: sociodemographic characteristics and health. Descriptive analysis and multivariate logistic regression models were performed. Results Relational CC was higher in Brazil than in Colombia both for PC physicians (82.2 and 72.9%, respectively) and for SC physicians (82.4 and 70.1%, respectively), but the perception of a good information transfer (informational CC) is lower (56.3 and 67.6%, respectively). No differences in the perception of consistency of care (managerial CC) were found (around 70%). Among the associated factors with CC, the following stand out: in Brazil, age (elderly) and area (Caruaru, remote town) was associated with any type of CC. In both countries, poor self-rated health was associated with lower levels of relational CC and in Colombia, also, with clinical management CC. In addition, in Colombia, having at least one chronic disease was associated with higher levels of any type of CC and sex (female) with a continuous relationship with PC physicians and informational CC. Conclusions The level of perceived relational and managerial continuity is high, and of informational continuity, low. Factors associated with the perception of continuity of care differ by countries and type of continuity of care. Key messages It is the first attempt to evaluate the three types of continuity of care in areas of Colombia and Brazil The understanding of the factors associated with the continuity of care will reveal which aspects of the public health system could be improve
Validación de la versión brasileña y colombiana de la escala CCAENA (continuidad de la atención en todos los niveles de atención): Irene Garcia-Subirats
Introducción El cuestionario de continuidad de la atención en todos los niveles de atención (CCAENA en español) evalúa los tres tipos de continuidad de la atención (relacional, informativa, gerencial) en todos los niveles de atención desde la perspectiva del paciente. Había sido validado para el contexto sanitario español. Objetivo: evaluar las propiedades psicométricas de la versión abreviada de la escala CCAENA en el contexto colombiano y brasileño. Métodos Estudio transversal mediante encuesta de población en municipios de Colombia (n = 2,163) y Brasil (n = 2,167). Los datos se recopilaron en 2011 mediante un cuestionario que incluía 14 ítems de la escala CCAENA adaptados a ambos contextos (y traducidos). Se evaluaron la validez de constructo (análisis factorial exploratorio), la consistencia interna (alfa de Cronbach) y la multidimensionalidad (coeficientes de correlación de Spearman). Resultados Al igual que en la versión original, el análisis factorial mostró que los ítems se agruparon en tres factores: la continuidad entre los niveles de atención y la relación entre el proveedor de atención primaria y el proveedor de atención secundaria. El alfa de Cronbach indicó una buena consistencia interna (Colombia: 0.87, 0.91, 0.87; Brasil: 0.86, 0.89, 0.86). Los coeficientes de correlación sugieren que los tres factores pueden interpretarse como escalas separadas (<0.70). Conclusión La validez y la confiabilidad de la versión abreviada de CCAENA son adecuadas en ambos países, manteniendo una alta equivalencia con la versión original, por lo tanto, es una herramienta útil para evaluar la continuidad de la atención en estos contextos. Mensajes clave Este estudio demuestra buenas propiedades psicométricas (validez y confiabilidad) de la versión abreviada de la escala CCAENA adaptada al contexto colombiano y brasileño. Esta herramienta será útil para proveedores e investigaciones para evaluar los tres tipos de continuidad de la atención en todos los niveles de atención desde la perspectiva del paciente en Colombia y Brasil. The Author 2014. Publicado por Oxford University Press en nombre de la Asociación Europea de Salud Pública. Todos los derechos reservados.Introduction The questionnaire of continuity of care across care levels (CCAENA in Spanish) assesses the three types of continuity of care (relational, informational, managerial) across care levels from the patient’s perspective. It had been validated for the Spanish health care context. Objective: To evaluate the psychometric properties of shortened version of the CCAENA scale in the Colombian and Brazilian context. Methods Cross-sectional study by means of a population survey in municipalities of Colombia (n = 2,163) and Brazil (n = 2,167). Data were collected in 2011 using a questionnaire that included 14 items of the CCAENA scale adapted to both contexts (and translated). Construct validity (exploratory factor analysis), internal consistency (Cronbach’s alpha) and multidimensionality (Spearman correlation coefficients) were assessed. Results As in the original version, the factor analysis showed that the items grouped into three factors: continuity across care levels and patient-primary care provider and -secondary care provider relationship. Cronbach’s alpha indicated good internal consistency (Colombia: 0.87, 0.91, 0.87; Brazil: 0.86, 0.89, 0.86). The correlation coefficients suggest that the three factors can be interpreted as separated scales (<0.70). Conclusion Validity and reliability of the shortened version of CCAENA are adequate in both countries – maintaining high equivalence with the original version – thus, is a useful tool to assess continuity of care in these contexts. Key messages This study demonstrates good psychometric properties - validity and reliability- of the shortened version of CCAENA scale adapted to the Colombian and Brazilian context. This tool will be useful for providers and researches to assess the three types of continuity of care across care levels from the patient’s perspective in Colombia and Brazil. The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved
Physical and biological drivers of sediment oxygenation and denitrification in a New Zealand intermittently closed and open lake lagoon
Relationship preferences and experience of primary care patients in continuity of care: a case study in Beijing, China
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