Estudio de prevalencia de enfermedad celíaca en pacientes con síndrome de intestino irritable

La Enfermedad Celíaca es una patología gastrointestinal crónica caracterizada por enteropatía inmuno-mediada, que puede ocasionar complicaciones a largo plazo, si no se realiza un diagnóstico precoz y no se instaura el tratamiento correspondiente, la dieta libre de gluten. Su prevalencia está descrita de 1%, pero se sabe es una condición sub-diagnosticada, debido principalmente al polimorfismo de la presentación clínica. Una de las patologías que se ha identificado como probable manifestación clínica de la Enfermedad Celíaca es el Síndrome de Intestino Irritable, condición que a su vez presenta una prevalencia de hasta 20%. En el presente estudio se realizó pesquisa de Enfermedad Celíaca en pacientes con diagnóstico de Síndrome de Intestino Irritable, en un consultorio de Gastroenterología en un hospital de tercer nivel. Se encontró una prevalencia de 7.69%, lo cual concuerda con resultados encontrados en otros estudios publicados. Esto permite concluir que dentro de la gama de cuadros clínicos con los que se puede manifestar la Enfermedad Celíaca se encuentra la sintomatología compatible con Síndrome de Intestino Irritable, por lo que es prudente sugerir que dentro del algoritmo de estudio de dicho síndrome se incluya la pesquisa de la misma.Celiac Disease is a chronic gastrointestinal disorder characterized by immune-mediated enteropathy that can lead to long-term complications if a timely diagnosis is not made, and adequate treatment, a gluten-free diet, is not established. Its prevalence has been described around 1%, but it is known that this disease is highly under-diagnosed, especially because of the ample polymorphism of its clinical presentation. One disorder that has been identified as a possible clinical manifestation of Celiac Disease is Irritable Bowel Syndrome, which has a prevalence of up to 20%. In the present study Celiac Disease screening was carried out in patients in whom Irritable Bowel Syndrome was diagnosed, in a Gastroenterology outpatient clinic, within a tertiary care hospital. A prevalence of 7.69% was found; which concurs with results found in other published studies. This leads to the conclusion that the symptomatology compatible with Irritable Bowel Syndrome can represent one of the clinical scenarios of Celiac Disease. And so it seems advisable to include screening for Celiac Disease in the diagnosis algorithm of Irritable Bowel Syndrome.Facultad de Ciencias Médica

Diseño de material gráfico editorial para la organización FUNCAGUA como apoyo a los procesos de concienciación de información Guatemala, Guatemala.

La fundación FUNCAGUA es una entidad creada con el fin de contribuir y fomentar la iniciativa del aprovechamiento sostenible y de la conservación de las fuentes de agua para la región metropolitana. Y en apoyo a esta institución, se presenta una propuesta de diseño de material gráfico editorial para medios impresos y digitales que facilite la comprensión de contenidos con respecto al uso responsable del agua y para llevar a cabo acciones eficientes. Las piezas gráficas finales son libro impreso, libro digital, invitaciones, afiches, post de redes sociales, diplomas, fondo de presentaciones. El concepto creativo seleccionado es “atesorando el caudal”, el cual engloba los objetivos y necesidades del problema, la retícula seleccionadas es modular, la paleta de colores seleccionadas en todos fríos, como el celeste y el verde

Guía para la conducción de procesos de ordenamiento territorial municipal

Bibliografía p. 85La presente guía tiene por objeto contribuir con los gobiernos municipales de Centroamérica y El Caribe en el fortalecimiento de sus capacidades para liderar procesos de ordenamiento y planificación territorial, como instrumentos clave de desarrollo.Incluye 13 buenas prácticas municipales en ordenamiento territoria

Seismological structure of the 1.8 Ga Trans-Hudson Orogen of North America

Precambrian tectonic processes are debated: what was the nature and scale of orogenic events on the younger, hotter, and more ductile Earth? Northern Hudson Bay records the Paleoproterozoic collision between the Western Churchill and Superior plates—the ∼1.8 Ga Trans-Hudson Orogeny (THO)—and is an ideal locality to study Precambrian tectonic structure. Integrated field, geochronological, and thermobarometric studies suggest that the THO was comparable to the present-day Himalayan-Karakoram-Tibet Orogen (HKTO). However, detailed understanding of the deep crustal architecture of the THO, and how it compares to that of the evolving HKTO, is lacking. The joint inversion of receiver functions and surface wave data provides new Moho depth estimates and shear velocity models for the crust and uppermost mantle of the THO. Most of the Archean crust is relatively thin (∼39 km) and structurally simple, with a sharp Moho; upper-crustal wave speed variations are attributed to postformation events. However, the Quebec-Baffin segment of the THO has a deeper Moho (∼45 km) and a more complex crustal structure. Observations show some similarity to recent models, computed using the same methods, of the HKTO crust. Based on Moho character, present-day crustal thickness, and metamorphic grade, we support the view that southern Baffin Island experienced thickening during the THO of a similar magnitude and width to present-day Tibet. Fast seismic velocities at >10 km below southern Baffin Island may be the result of partial eclogitization of the lower crust during the THO, as is currently thought to be happening in Tibet

Array-conditioned deconvolution of multiple component teleseismic recordings

We investigate the applicability of an array-conditioned deconvolution technique, developed for analyzing borehole seismic exploration data, to teleseismic receiver functions and data preprocessing steps for scattered wavefield imaging. This multichannel deconvolution technique constructs an approximate inverse filter to the estimated source signature by solving an overdetermined set of deconvolution equations, using an array of receivers detecting a common source. We find that this technique improves the efficiency and automation of receiverfunction calculation and data preprocessing workflow. We apply this technique to synthetic experiments and to teleseismic data recorded in a dense array in northern Canada. Our results show that this optimal deconvolution automatically determines and subsequently attenuates the noise from data, enhancing P-to-S converted phases in seismograms with various noise levels. In this context, the array-conditioned deconvolution presents a new, effective and automatic means for processing large amounts of array data, as it does not require any ad-hoc regularization; the regularization is achieved naturally by using the noise present in the array itself

Ray-parameter based stacking and enhanced pre-conditioning for stable inversion of receiver function data

While inversion of seismic velocity from receiver function data could be instable due to its intrinsic non-linearity and non-uniqueness, improper stacking of receiver function could also introduce significant biases to the resulting velocity structure. In a distance section of receiver functions, the Moho Ps conversion and the two reverberations possess a positive and negative moveout, respectively. Stacking receiver functions without moveout correction could significantly reduce and distort the amplitude and waveform of these phases. Inversion with these incorrectly stacked receiver functions will thus inevitably introduce artefacts to the resulting velocity structure. In this study, we have improved the inversion procedure in two ways. First, we introduce a ray-parameter based (RPB) stacking method to correctly construct receiver function data for inversion. Specifically we develop a ‘four-pin’ method that accounts for the moveout effect of the converted and reverberated phases in stacking individual receiver functions recorded at various distances. Secondly, we divide the receiver function trace into conversion and reverberation windows and assign different weights between the two windows in the inversion. More weight is given to the Ps conversion window in resolving the shallow structure, which can be nearly fixed in the successive inversion of deeper structure. We also employ other pre-conditioning proposed by previous studies, such as balancing the receiver function data being filtered with different Gaussian filters, smoothing the velocity model and further regulating the model based on existing information. We compute synthetic receiver functions at distances between 30◦ and 90◦ from a target model and then use the RPB stacking method to generate the input data for various inversions (iterative linear) with different initial models. Our inversions with enhanced pre-conditioning and RPB stacked data demonstrate a good capability in recovering the target model from generally more stable iterations. Applying these techniques to two broad-band stations in China indicates that the improvements on data stacking and inversion can eliminate potential stacking-induced artefacts, and yield models more consistent with surface geology

Crustal Formation on a Spreading Ridge Above a Mantle Plume: Receiver Function Imaging of the Icelandic Crust

Iceland sits astride a mid-ocean ridge underlain by a {mantle} hotspot. The interplay of these two geological processes has the potential to generate a complex and laterally variable crustal structure. The thickness of the Icelandic crust is a long running and controversial debate, with estimates ranging from a "thin'' 20 km crust to a "thick'' 40 km crust. We present new images of the first order seismic discontinuity structure of the Icelandic crust based on a joint inversion of receiver function and ambient noise derived surface wave dispersion data. Inversion results are validated through comparison to receiver functions multi-phase common conversion point stacks across the densely instrumented Northern Volcanic Zone. We find a multi-layered crustal structure consisting of a 6-10 km deep upper crust underlain by either one or two discontinuities. The shallower discontinuity is found at depths of ~20 km throughout Iceland. The deeper discontinuity is only present in some regions, defining the base of a lens-like lower layer with maximum depths of 44 km above the center of the mantle plume. Either of these two discontinuities could be interpreted as the seismic Moho, providing an explanation why previous estimates of crustal thickness have diverged. Such structure may form via underplating of a pre-existing oceanic crust as has been hypothesized in other ocean island plume settings. However we demonstrate with a simple petrological model that variability in seismic discontinuity structure can also be understood as a consequence of compositional variation in melts generated with distance from the plume center

USArray Imaging of Continental Crust in the Conterminous United States

The thickness and bulk composition of continental crust provide important constraints on the evolution and dynamics of continents. Crustal mineralogy and thickness both may influence gravity anomalies, topographic elevation, and lithospheric strength, but prior to the inception of EarthScope’s USArray, seismic measurements of crustal thickness and properties useful for inferring lithology are sparse. Here we improve upon a previously published methodology for joint inversion of Bouguer gravity anomalies and seismic receiver functions by using parameter space stacking of cross correlations of modeled synthetic and observed receiver functions instead of standard H-κ amplitude stacking. The new method is applied to estimation of thickness and bulk seismic velocity ratio, vP/vS, of continental crust in the conterminous United States using USArray and other broadband network data. Crustal thickness variations are reasonably consistent with those found in other studies and show interesting relationships to the history of North American continental formation. Seismic velocity ratios derived in this study are more robust than in other analyses and hint at large-scale variations in composition of continental crust. To interpret the results, we model the pressure-/temperature-dependent thermodynamics of mineral formation for various crustal chemistries, with and without volatile constituents. Our results suggest that hydration lowers bulk crustal vP/vS and density and releases heat in the shallow crust but absorbs heat in the lowermost crust (where plagioclase breaks down to pyroxene and garnet resulting in higher seismic velocity). Hence, vP/vS variations may provide a useful proxy for hydration state in the crust