69 research outputs found
Experiencia en reparación quirúrgica de lesiones iatrógenas de la vía biliar en el hospital Carlos Andrade Marín
La patología apendicular es la enfermedad más frecuente que requiere cirugía en las salas de urgencias. La apendicetomía laparoscópica es el manejo estándar de la apendicitis aguda en cualquiera de sus etapas en el Servicio de Cirugía Pediátrica y es el procedimiento más frecuentemente realizado en el servicio. El siguiente estudio tiene por objeto evaluar la prevalencia de resistencia bacteriana a múltiples fármacos con la finalidad de establecer conclusiones certeras epidemiológicas regionales
Simultaneous biohydrogen production and purification in a double-membrane bioreactor system
In this work the establishment of a double-membrane bioreactor was aimed. Initially, a continuous hydrogen fermenter was coupled with a commercial Kubota® microfiltration membrane module and the production performance of the cell-retentive design was evaluated under various hydraulic retention times. As a result, it has been observed that altering HRT influenced the rejection feature of the microfiltration module while had an inverse effect on hydrogen productivity and yield, since shortened HRTs were accompanied by gradually decreasing H2 yields (HY) and progressively increasing volumetric H2 production rates (HPR). The highest HY and HPR were achieved as 1.13 mol H2/mol glucose and 0.24 mol H2/L-d, respectively. Furthermore, a Permselect® (PDMS) gas separation membrane was installed to the anaerobic membrane bioreactor and its ability to separate hydrogen from the raw fermentation gaseous mixture was assessed. The highest purity hydrogen obtained in one-step purification by the PDMS module was 67.3 vol.%, which exceeds 30% enrichment efficiency considering 51.3 vol.% H2 in the feed gas. Hence, it could be concluded that the poly(dimethyl siloxane) membrane has potential to attractively concentrate biohydrogen from fermenter off-gas and may be used for in-situ product recovery
Simultaneous biohydrogen production and purification in a double-membrane bioreactor system
Global and regional ecological boundaries explain abrupt spatial discontinuities in avian frugivory interactions
Species interactions can propagate disturbances across space via direct and indirect effects, potentially connecting species at a global scale. However, ecological and biogeographic boundaries may mitigate this spread by demarcating the limits of ecological networks. We tested whether large-scale ecological boundaries (ecoregions and biomes) and human disturbance gradients increase dissimilarity among plant-frugivore networks, while accounting for background spatial and elevational gradients and differences in network sampling. We assessed network dissimilarity patterns over a broad spatial scale, using 196 quantitative avian frugivory networks (encompassing 1496 plant and 1004 bird species) distributed across 67 ecoregions, 11 biomes, and 6 continents. We show that dissimilarities in species and interaction composition, but not network structure, are greater across ecoregion and biome boundaries and along different levels of human disturbance. Our findings indicate that biogeographic boundaries delineate the world’s biodiversity of interactions and likely contribute to mitigating the propagation of disturbances at large spatial scales.The authors acknowledge the following funding: University of Canterbury Doctoral Scholarship (L.P.M.); The Marsden Fund grant UOC1705 (J.M.T., L.P.M.); The São Paulo Research Foundation - FAPESP 2014/01986-0 (M.G., C.E.), 2015/15172-7 and 2016/18355-8 (C.E.), 2004/00810-3 and 2008/10154-7 (C.I.D., M.G., M.A.P.); Earthwatch Institute and Conservation International for financial support (C.I.D., M.G., M.A.P.); Carlos Chagas Filho Foundation for Supporting Research in the Rio de Janeiro State – FAPERJ grant E-26/200.610/2022 (C.E.); Brazilian Research Council grants 540481/01-7 and 304742/2019-8 (M.A.P.) and 300970/2015-3 (M.G.); Rufford Small Grants for Nature Conservation No. 22426–1 (J.C.M., I.M.), No. 9163-1 (G.B.J.) and No. 11042-1 (MCM); Universidade Estadual de Santa Cruz (Propp-UESC; No. 00220.1100.1644/10-2018) (J.C.M., I.M.); Fundação de Amparo à Pesquisa do Estado da Bahia - FAPESB (No. 0525/2016) (J.C.M., I.M.); European Research Council under the European Union’s Horizon 2020 research and innovation program (grant 787638) and The Swiss National Science Foundation (grant 173342), both awarded to C. Graham (D.M.D.); ARC SRIEAS grant SR200100005 Securing Antarctica’s Environmental Future (D.M.D.); German Science Foundation—Deutsche Forschungsgemeinschaft PAK 825/1 and FOR 2730 (K.B.G., E.L.N., M.Q., V.S., M.S.), FOR 1246 (K.B.G., M.S., M.G.R.V.) and HE2041/20-1 (F.S., M.S.); Portuguese Foundation for Science and Technology - FCT/MCTES contract CEECIND/00135/2017 and grant UID/BIA/04004/2020 (S.T.) and contract CEECIND/02064/2017 (L.P.S.); National Scientific and Technical Research Council, PIP 592 (P.G.B.); Instituto Venezolano de Investigaciones Científicas - Project 898 (V.S.D.)
Tratamiento de efluentes acuosos contaminados con compuestos organoclorados
[ES] Los compuestos organoclorados son un tipo de residuos que han adquirido especial relevancia en los últimos tiempos, debido a sus características tóxicas y peligrosas, tanto para el medio ambiente como para los seres humanos. Su especial peligrosidad ha potenciado la búsqueda de alternativas para su tratamiento en las distintas corrientes donde se presentan. En este artículo se describe la problemática real de este tipo de compuestos, se exponen los principales contaminantes y se muestra una visión general de las alternativas para la eliminación de estos organoclorados de corrientes acuosas, detallándose en profundidad una de las alternativas de eliminación consideradas: la hidrodecloración catalítica en fase acuosa.Padilla Vivas, B.; Díez Sanz, FV.; Ordóñez García, S. (2005). Tratamiento de efluentes acuosos contaminados con compuestos organoclorados. 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Epidemiología y características del ictus isquémico en el adulto joven en Aragón
Introducción
Alrededor de 15 millones de personas sufren un ictus cada año, de los que un 10-15% ocurre en menores de 50 años (ictus en el adulto joven). La prevalencia de los distintos factores de riesgo vascular y las estrategias sanitarias para el manejo del ictus varían a nivel mundial, siendo interesante conocer la epidemiología y las características específicas de cada región.
El objetivo de este estudio fue determinar la prevalencia de los diferentes factores de riesgo vascular, la etiología y las características de los ictus isquémicos en el adulto joven en la comunidad autónoma de Aragón.
Métodos
Estudio multicéntrico, de corte transversal, realizado por los Servicios de Neurología de todos los hospitales del Servicio Aragonés de Salud (SALUD). Se identificó a todos los pacientes entre 18 y 50 años que ingresaron en cualquiera de estos hospitales con el diagnóstico de ictus isquémico o AIT entre enero del 2005 y diciembre del 2015. Se recogieron variables demográficas, factores de riesgo vascular y tipo de ictus isquémico entre otras.
Resultados
En el periodo de estudio, 786 pacientes entre 18 y 50 años ingresaron con el diagnóstico de ictus isquémico o AIT en algún hospital del SALUD, con una tasa anual promedio de 12, 3 por 100.000 habitantes. La mediana de su edad fue de 45 años (RIQ: 40-48 años). El factor de riesgo vascular más prevalente fue el tabaquismo, 404 (51, 4%). La mayoría fue de causa indeterminada (36, 2%), seguida por «otras causas» (26, 5%). La mediana de puntuación en la escala NIHSS fue de 3, 5 (RIQ: 2, 07, 0). En total, 211 (26, 8%) de los ingresos fueron por AIT. De los pacientes que ingresaron con el diagnóstico de ictus isquémico, 59 (10, 3%) se fibrinolizaron.
Conclusiones
El ictus isquémico en el adulto joven no es infrecuente en Aragón y en un importante número de casos es de etiología indeterminada, por lo que es necesario implementar medidas que nos permitan mejorar su estudio, disminuir su incidencia y prevenir su recurrencia.
Introduction: Stroke affects around 15 million people per year, with 10%-15% occurring in individuals under 50 years old (stroke in young adults). The prevalence of different vascular risk factors and healthcare strategies for stroke management vary worldwide, making the epidemiology and specific characteristics of stroke in each region an important area of research. This study aimed to determine the prevalence of different vascular risk factors and the aetiology and characteristics of ischaemic stroke in young adults in the autonomous community of Aragon, Spain.
Methods: A cross-sectional, multi-centre study was conducted by the neurology departments of all hospitals in the Aragonese Health Service. We identified all patients aged between 18 and 50 years who were admitted to any of these hospitals with a diagnosis of ischaemic stroke or TIA between January 2005 and December 2015. Data were collected on demographic variables, vascular risk factors, and type of stroke, among other variables.
Results: During the study period, 786 patients between 18 and 50 years old were admitted with a diagnosis of ischaemic stroke or TIA to any hospital of Aragon, at a mean annual rate of 12.3 per 100 000 population. The median age was 45 years (IQR: 40-48 years). The most prevalent vascular risk factor was tobacco use, in 404 patients (51.4%). The majority of strokes were of undetermined cause (36.2%), followed by other causes (26.5%). The median NIHSS score was 3.5 (IQR: 2.0-7.0). In total, 211 patients (26.8%) presented TIA. Fifty-nine per cent of the patients admitted with a diagnosis of ischaemic stroke (10.3%) were treated with fibrinolysis.
Conclusions: Ischaemic stroke in young adults is not uncommon in Aragon, and is of undetermined aetiology in a considerable number of cases; it is therefore necessary to implement measures to improve study of the condition, to reduce its incidence, and to prevent its recurrence
Descoloração do corante Azul Brilhante de Remazol R por leveduras isoladas de moluscos do Rio Subaé, no estado da Bahia, Brasil
¿Nos entendemos entre médicos y pacientes? el caso e una comunidad de la Provincia de Cotopaxi.
La humanidad desde los tiempo remotos, han intentado dar alivio a sus dolencias físicas o psicológicas. En muchos casos, esta búsqueda se tornó en ensayo – error, lo que significo seguramente la pérdida de vidas en manos de quienes crecían saber cómo curar enfermedades o, al menos, alivias el dolor.
Seguramente, desde el hombre primitivo hasta la actualidad, se deben haber probado una infinidad de sustancias, brebajes, ritos, medicamentos, etc.; al igual que un sinfín de técnicas de diagnóstico, muchos de estos con resultados no siempre satisfactorios.
En todo caso, siempre se ha intentado traducir lo que los enfermos dicen que siente a lo que desde su objetividad se evidencia en los enfermos, por parte de quienes asumen la tarea de curar, con el fin de lograr una asociación entre lo que dice el enfermo, lo que evidencia quien intenta curar y lo que más tarde se constituirá en indicativo de una enfermedad
Hydrogen production in a microbial electrolysis cell fed with a dark fermentation effluent
The organic matter consumption and hydrogen production rate were evaluated in a two-chamber microbial electrolysis cell (MEC). Three chemical oxygen demand (COD) concentration levels (400, 600 and 1200 mg/L) were tested. The COD was composed of a mixture of volatile fatty acids (VFAs) present in the effluent of a dark fermentation process. The two levels of voltage studied were 350 and 550 mV. The performance of the MEC was evaluated using either an anionic (AEM) or cationic exchange membrane (CEM). The robustness of the MEC was tested using two dark fermentation effluents, one with VFAs and another containing 1100 mg/L glucose. The highest production rates (81 mL/L/day) were obtained with 550 mV, and 85 % COD consumption was attained. No considerable differences in the hydrogen production rate were observed when the COD was increased from 400 to 1200 mg/L using 550 mV. However, maximal hydrogen production rates were obtained with the lower COD concentration using 350 mV. Neither the employment of AEM and CEM nor the change from synthetic substrate to real substrate resulted in remarkable changes in MEC performance. The substrate containing glucose was more slowly degraded because glucose was first transformed into VFAs, and then the VFAs were consumed to produce hydrogen. In this case, methane and carbon dioxide were detected. © 2015 Springer Science+Business Media Dordrech
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