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River discharge and nutrient measurements are subject to aleatory and epistemic uncertainties. In this study, we present a novel method for estimating these uncertainties in colocated discharge and phosphorus (P) measurements. The “voting point”‐based method constrains the derived stage‐discharge rating curve both on the fit to available gaugings and to the catchment water balance. This helps reduce the uncertainty beyond the range of available gaugings and during out of bank situations. In the example presented here, for the top 5% of flows, uncertainties are shown to be 139% using a traditional power law fit, compared with 40% when using our updated “voting point” method. Furthermore, the method is extended to in situ and lab analysed nutrient concentration data pairings, with lower uncertainties (81%) shown for high concentrations (top 5%) than when a traditional regression is applied (102%). Overall, for both discharge and nutrient data, the method presented goes some way to accounting for epistemic uncertainties associated with nonstationary physical characteristics of the monitoring site.

There is a need to model and predict the transfer of phosphorus (P) from land to water, but this is challenging because of the large number of complex physical and biogeochemical processes involved. This study presents, for the first time, a ‘limits of acceptability’ approach of the Generalized Likelihood Uncertainty Estimation (GLUE) framework to the Soil and Water Assessment Tool (SWAT), in an application to a water quality problem in the Newby Beck Catchment (12.5km2), Cumbria, United Kingdom (UK). Using high frequency outlet data (discharge and P), individual evaluation criteria (limits of acceptability) were assigned to observed discharge and P loads for all evaluation time steps, identifying where the model was performing well/poorly and to infer which processes required improvement in the model structure. Initial limits of acceptability were required to be relaxed by a substantial amount (by factors of between 5.3 and 6.72 on a normalized scale depending on the evaluation criteria used) in order to gain a set of behavioral simulations (1001 and 1016, respectively out of 5,000,000). Of the 39 model parameters tested, the representation of subsurface processes and associated parameters, were consistently shown as critical to the model not meeting the evaluation criteria, irrespective of the chosen evaluation metric. It is therefore concluded that SWAT is not an appropriate model to guide P management in this catchment. This approach highlights the importance of high frequency monitoring data for setting robust model evaluation criteria. It also raises the question as to whether it is possible to have sufficient input data available to drive such models so that we can have confidence in their predictions and their ability to inform catchment management strategies to tackle the problem of diffuse pollution from agriculture.

There is a need to model and predict the transfer of phosphorus (P) from land to water, but this is challenging because of the large number of complex physical and biogeochemical processes involved. This study presents, for the first time, a ‘limits of acceptability’ approach of the Generalized Likelihood Uncertainty Estimation (GLUE) framework to the Soil and Water Assessment Tool (SWAT), in an application to a water quality problem in the Newby Beck Catchment (12.5km2), Cumbria, United Kingdom (UK). Using high frequency outlet data (discharge and P), individual evaluation criteria (limits of acceptability) were assigned to observed discharge and P loads for all evaluation time steps, identifying where the model was performing well/poorly and to infer which processes required improvement in the model structure. Initial limits of acceptability were required to be relaxed by a substantial amount (by factors of between 5.3 and 6.72 on a normalized scale depending on the evaluation criteria used) in order to gain a set of behavioral simulations (1001 and 1016, respectively out of 5,000,000). Of the 39 model parameters tested, the representation of subsurface processes and associated parameters, were consistently shown as critical to the model not meeting the evaluation criteria, irrespective of the chosen evaluation metric. It is therefore concluded that SWAT is not an appropriate model to guide P management in this catchment. This approach highlights the importance of high frequency monitoring data for setting robust model evaluation criteria. It also raises the question as to whether it is possible to have sufficient input data available to drive such models so that we can have confidence in their predictions and their ability to inform catchment management strategies to tackle the problem of diffuse pollution from agriculture.

Excess nutrients in surface waters, such as phosphorus (P) from agriculture, result in poor water quality, with adverse effects on ecological health and costs for remediation. However, understanding and prediction of P transfers in catchments have been limited by inadequate data and over-parameterised models with high uncertainty. We show that, with high temporal resolution data, we are able to identify simple dynamic models that capture the P load dynamics in three contrasting agricultural catchments in the UK. 10 For a flashy catchment, a linear, second-order (two pathways) model for discharge gave high simulation efficiencies for short-term storm sequences and was useful in highlighting uncertainties in out-of-bank flows. A model with nonlinear rainfall input was appropriate for predicting seasonal 15 or annual cumulative P loads where antecedent conditions affected the catchment response. For second-order models, the time constant for the fast pathway varied between 2 and 15 h for all three catchments and for both discharge and P, confirming that high temporal resolution data are necessary 20 to capture the dynamic responses in small catchments (10–50 km2/. The models led to a better understanding of the dominant nutrient transfer modes, which will be helpful in determining phosphorus transfers following changes in precipitation patterns in the future.

Excess nutrients in surface waters, such as phosphorus (P) from agriculture, result in poor water quality, with adverse effects on ecological health and costs for remediation. However, understanding and prediction of P transfers in catchments have been limited by inadequate data and over-parameterised models with high uncertainty. We show that, with high temporal resolution data, we are able to identify simple dynamic models that capture the P load dynamics in three contrasting agricultural catchments in the UK. For a flashy catchment, a linear, second-order (two pathways) model for discharge gave high simulation efficiencies for short-term storm sequences and was useful in highlighting uncertainties in out-of-bank flows. A model with non-linear rainfall input was appropriate for predicting seasonal or annual cumulative P loads where antecedent conditions affected the catchment response. For second-order models, the time constant for the fast pathway varied between 2 and 15 h for all three catchments and for both discharge and P, confirming that high temporal resolution data are necessary to capture the dynamic responses in small catchments (10–50 km2). The models led to a better understanding of the dominant nutrient transfer modes, which will be helpful in determining phosphorus transfers following changes in precipitation patterns in the future.

Phosphorus (P) losses from land to water will be impacted by climate change and land management for food production, with detrimental impacts on aquatic ecosystems. Here we use a unique combination of methods to evaluate the impact of projected climate change on future P transfers, and to assess what scale of agricultural change would be needed to mitigate these transfers. We combine novel high frequency P flux data from three representative catchments across the UK, a new high spatial resolution climate model, uncertainty estimates from an ensemble of future climate simulations, two P transfer models of contrasting complexity and a simplified representation of the potential intensification of agriculture based on expert elicitation from land managers. We show that the effect of climate change on average winter P loads (predicted increase up to 30% by 2050s) will be limited only by large scale agricultural changes (e.g. 20-80% reduction in P inputs).

Climate projections for the future indicate that the United Kingdom will experience hotter, drier summers and warmer, wetter winters, bringing longer dry periods followed by rewetting. This will result in changes in phosphorus (P) mobilization patterns that will influence the transfer of P from land to water. We tested the hypothesis that changes in the future patterns of drying–rewetting will affect the amount of soluble reactive phosphorus (SRP) solubilized from soil. Estimations of dry period characteristics (duration and temperature) under current and predicted climate were determined using data from the UK Climate Projections (UKCP09) Weather Generator tool. Three soils (sieved <2 mm), collected from two regions of the United Kingdom with different soils and farm systems, were dried at 25°C for periods of 0, 2, 4, 5, 6, 8, 10, 15, 20, 25, 30, 60, and 90 d, then subsequently rewetted (50 mL over 2 h). The solubilized leachate was collected and analyzed for SRP. In the 2050s, warm period temperature extremes >25°C are predicted in some places and dry periods of 30 to 90 d extremes are predicted. Combining the frequency of projected dry periods with the SRP concentration in leachate suggests that this may result overall in increased mobilization of P; however, critical breakpoints of 6.9 to 14.5 d dry occur wherein up to 28% more SRP can be solubilized following a rapid rewetting event. The precise cause of this increase could not be identified and warrants further investigation as the process is not currently included in P transfer models.

We hypothesise that climate change, together with intensive agricultural systems, will increase the transfer of pollutants from land to water and impact on stream health. This study builds, for the first time, an integrated assessment of nutrient transfers, bringing together a) high-frequency data from the outlets of two surface water-dominated, headwater (~ 10 km²) agricultural catchments, b) event-by-event analysis of nutrient transfers, c) concentration duration curves for comparison with EU Water Framework Directive water quality targets, d) event analysis of location-specific, sub-daily rainfall projections (UKCP, 2009), and e) a linear model relating storm rainfall to phosphorus load. These components, in combination, bring innovation and new insight into the estimation of future phosphorus transfers, which was not available from individual components. The data demonstrated two features of particular concern for climate change impacts. Firstly, the bulk of the suspended sediment and total phosphorus (TP) load (greater than 90% and 80% respectively) was transferred during the highest discharge events. The linear model of rainfall-driven TP transfers estimated that, with the projected increase in winter rainfall (+ 8% to + 17% in the catchments by 2050s), annual event loads might increase by around 9% on average, if agricultural practices remain unchanged. Secondly, events following dry periods of several weeks, particularly in summer, were responsible for high concentrations of phosphorus, but relatively low loads. The high concentrations, associated with low flow, could become more frequent or last longer in the future, with a corresponding increase in the length of time that threshold concentrations (e.g. for water quality status) are exceeded. The results suggest that in order to build resilience in stream health and help mitigate potential increases in diffuse agricultural water pollution due to climate change, land management practices should target contro

En región de premolares con disminución de espacio en la zona edéntula, los implantes con diámetro de 3mm y de una sola pieza, son una buena alternativa, siempre que se cuente con buena calidad y densidad ósea. Acorde a la literatura, la técnica quirúrgica Flapless conserva los tejidos blandos y ofrece al paciente un postoperatorio más satisfactorio. Por su parte, la carga inmediata por estética es la más aconsejable en estos casos, además de la realización de la corona definitiva en zirconio. El propósito de estos procedimientos restaurativos fue mejorar la estética dental con tratamientos poco invasivos y mantener la función masticatoria y fonatoria normal. El reporte presenta el caso de una mujer de 48 años de edad, con espacio edéntulo del 15 reemplazado por corona en cantilever. Posterior a la realización de los procedimientos de higiene oral, se dio inicio al encerado diagnóstico, análisis en la ubicación del implante, retiro de coronas, preparación de provisionales, colocación del implante de un solo cuerpo, cirugía con técnica de Flapless, carga inmediata, y colocación de corona definitiva en zirconio (CAD-CAM).[Mendoza MC, Galeano CF. Colocación de un implante de un solo cuerpo con técnica quirúrgica Flapless, carga inmediata y rehabilitación en zirconio: reporte de un caso. Ustasalud 2012; 11: 54 - 59], In the premolars region with space reduction of the edentulous zone, the 3mm and one piece implants are a good choice, as long as there is good quality and bone density. According to the literature found, the surgical Flapless technique preserves the soft tissues, offering the patient a more pleasant post treatment time. In these cases, the immediate esthetic load is the most recommended one, doing the definitive crown in zirconium. The purpose of these restorative procedures were to improve the dental esthetics through less invasive treatments and to maintain the normal masticatory and phonatory functions. The report shows a 48-year-old female patient, with edentulous space in the 15, replacement by a crown in cantilever. After doing the oral hygiene procedures, the wax diagnostic begin with the implant location analysis, crowns removal, temporaries collocation, one piece implant placement, technical Flapless surgery, immediate load and finally definitive zirconium crown placement (CAD-CAM).

Objective: To assess the performance of zirconium oxide (Y-TZP) ceramic coated with different thicknesses shear forces.Methods: an In vitro experimental study was done with thirty zirconium dioxide cylinders coated with VITA VM 9 at different thicknesses (1.0 mm, 1.5 mm and 2.0 mm), they were subjected to shear forces. The control group consisted in metal-ceramic rods coated with VITA VM13. We evaluated the interface, the severity of delamination of the ceramic, the shape of the fracture, the type of material, the thickness of the ceramic and pottery effort measured in MPa. The variables were analyzed according to their nature and distribution; the tests used were Chi2, U. Mann Whitney and a logistic regression.Results: 93.22% of the samples suffered delamination of the adhesive type. The 49.15% were zirconium dioxide samples. Minor faults were obtained on a sample of 47.46% and 18.64% in severe. The material could increase the severity of delamination (3.24 times more) but the difference was not statistically significant (OR 3.24 95% CI 0.91 – 1.16).Conclusions: delamination of the ceramic is not directly proportional to the thickness. Furthermore, the zirconium dioxide presented low shear strength., Objetivo: evaluar el comportamiento del dióxido de zirconio (Y-TZP) recubierto con diferentes grosores cerámicos ante fuerzas de cizalla.Materiales y métodos: se realizó un estudio experimental In vitro con treinta cilindros de dióxido de zirconio recubiertos con cerámica VITA VM9 de diferentes grosores (1mm, 1,5mm y 2mm) sometidos a fuerzas de cizallamiento. El grupo control lo conformaron barras de metal-cerámica recubiertas con VITA VM13. Se evaluó la interfase, la severidad de la deslaminación de la cerámica, la morfología de la fractura, el tipo de material, el grosor de la cerámica y el esfuerzo de la cerámica medido en Mpa. Las variables se analizaron de acuerdo con su naturaleza y distribución, se llevaron a cabo pruebas de Chi2, U. de Mann Whitney y también se realizó una regresión logística.Resultados: el 93,22% de las muestras sufrió deslaminación de tipo adhesivo. El 49,15% correspondieron a muestras de dióxido de zirconio. Hubo fallas leves en el 47,46% de las muestras y severas en el 18,64%. El tipo de material podría aumentar la severidad de la deslaminación (3,24 veces más) aunque la diferencia no fue estadísticamente significativa (OR 3,24 IC 95% 0,91 – 1,16).Conclusiones: la deslaminación de la cerámica no es directamente proporcional al grosor. Además, el dióxido de zirconio presentó una resistencia al cizallamiento baja.[Mendoza MC, Rueda CA, Barranco Y, Delgado MJ, Mesa E, Otero J. Comportamiento In vitro con diferentes grosores cerámicos sobre estructuras de dióxido de zirconio (y-tzp) ante fuerzas de cizallamiento. Ustasalud 2012; 11: 32 - 36]

Purpose: To evaluate the efficiency of chlorhexidine mouthwash over the amount of bacterian plaque present in adults with orthodontic treatment appliances, living in the Bucaramanga metropolitan area, patients that attend the Santo Tomas University dental clinics, during the second semester of 2007.Materials and Methods: A controlled clinical essay was performed in 60 adults with orthodontic appliances. It was established the OPI plaque index (Ortho-Plaque index) and the gingival index (GI index). The experimental group received the basic maintenance therapy, chlorhexidine digluconate at 0.2% to be used as a 10 ml non dilute mouthwash, twice (2) a day for 15 days.Results: The patients exposed to the intervention had 2.2 times probability (1.6 versus 3.3) of their IC to get the OPI index whose values reflect a good oral hygiene.Conclusions: The patients with orthodontic appliances who used chlorhexidine digluconate (0.2%), for fifteen days long had a significant reduction of bacterian plaque., Objetivo: Determinar la eficacia de la clorhexidina sobre la cantidad de placa dental presente en sujetos adultos, usuarios de aparatología ortodoncica y residentes en el área metropolitana de Bucaramanga que eran atendidos en las clínicas de ortodoncia de la universidad Santo Tomas, durante el segundo semestre del año 2007.Materiales y métodos: Ensayo clínico controlado realizado con 60 sujetos adultos en tratamiento de ortodoncia. Se estableció el índice de placa OPI (Ortho-Plaque Index) y el índice gingival (GI Index). El grupo intervenido recibió 10 ml de Digluconato de Clorhexidina (0,2%), que se utilizó en forma de enjuagues dos veces por día, sin interrupciones por quince días.Resultados: Los sujetos expuestos a la intervención tenían 2.2 veces más de probabilidad IC (1.6 a 3.3) de tener un índice OPI cuyos valores reflejaban una buena higiene oral.Conclusiones: Se podría afirmar que la exposición de los sujetos, con tratamiento de ortodoncia, al Digluconato de Clorhexidina (0.2%), por un periodo de quince días, disminuyó la placa dental significativamente.[Ibañez E, Aguilar LA, Mendoza MC. Eficacia del uso del enjuague de clorhexidina durante el tratamiento de ortodoncia. Revista Ustasalud Odontología 2007; 6: 112 - 122]

El objetivo principal de esta investigación es diseñar un Objeto Virtual de Aprendizaje (OVA) para la enseñanza del español como segunda lengua (E2L) desde una perspectiva intercultural. Se trata de un material didáctico complementario que permita apoyar las prácticas de enseñanza de los etnoeducadores que trabajan con comunidades indígenas en Colombia. Esto debido a que el diseño de materiales para esta población es escaso o descontextualizado, por lo cual se pretende contribuir a que su proceso de formación en el área del español se acerque más a su realidad y a sus necesidades. La investigación retoma los planteamientos de Santos-Gargallo (2015) y Manga (2008) en cuanto a la enseñanza de una segunda lengua (L2), Hostia (2016) en el ámbito de la etnoeducación y Vargas (2013) y Walsh (2005) en el campo de la interculturalidad. Además de estos referentes, que fundamentan el material diseñado, se consideraron las metodologías propuestas por Graves (1996) y Morales et al. (2016), las cuales se integraron en una ruta de ocho pasos que favorecen la planeación y el diseño de un OVA. El OVA fue evaluado por tres etnoeducadores de la comunidad Embera-Chamí y dos expertos, ya que, debido a las limitaciones de tiempo, no fue posible realizar un pilotaje con la población objetivo del estudio. A partir de los criterios sugeridos por la rejilla LORI-AD, el material fue valorado como bueno y se aprobó su publicación. A partir del proceso investigativo se concluye que, a nivel conceptual, el diseño de estos materiales representa un reto, debido a las dificultades de hallar un concepto unificado sobre los OVA y una ruta metodológica clara para su creación. A nivel pedagógico, se evidencia el auge del español como lengua extranjera (ELE) en la actualidad, sin embargo, en el caso del E2L este panorama es completamente diferente, evidenciándose, en este caso, descontextualización de los materiales y omisión de elementos interculturales en estos. Por último, a nivel investigativo, se