281 research outputs found
The impact of age and comorbidity on the postoperative outcomes after emergency surgical management of complicated intra-abdominal infections
Age-adjusted Charlson Comorbidity Index (a-CCI) score has been used to weight comorbid conditions in predicting adverse outcomes. A retrospective cohort study on adult patients diagnosed with complicated intra-abdominal infections (cIAI) requiring emergency surgery was conducted in order to elucidate the role of age and comorbidity in this scenario. Two main outcomes were evaluated: 90-day severe postoperative complications (grade ≥ 3 of Dindo-Clavien Classification), and 90-day all-cause mortality. 358 patients were analyzed. a-CCI score for each patient was calculated and then divided in two comorbid categories whether they were ≤ or > to percentile 75 (= 4): Grade-A (0–4) and Grade-B (≥ 5). Univariate and multivariate regression analyses were performed, and the predictive validity of the models was evaluated by the area under the receiver operating characteristics (AUROC) curve. Independent predictors of 90-day severe postoperative complications were Charlson Grade-B (Odds Ratio [OR] = 3.49, 95% confidence interval [95%CI]: 1.86–6.52; p < 0.0001), healthcare-related infections (OR = 7.84, 95%CI: 3.99–15.39; p < 0.0001), diffuse peritonitis (OR = 2.64, 95%CI: 1.45–4.80; p < 0.01), and delay of surgery > 24 hours (OR = 2.28, 95%CI: 1.18–4.68; p < 0.02). The AUROC was 0.815 (95%CI: 0.758–0.872). Independent predictors of 90-day mortality were Charlson Grade-B (OR = 8.30, 95%CI: 3.58–19.21; p < 0.0001), healthcare-related infections (OR = 6.38, 95%CI: 2.72–14.95; p < 0.0001), sepsis status (OR = 3.98, 95%CI: 1.04–15.21; p < 0.04) and diffuse peritonitis (OR = 3.06, 95%CI: 1.29–7.27; p < 0.01). The AUROC for mortality was 0.887 (95%CI: 0.83–0.93). Post-hoc sensitivity analyses confirmed that the degree of comorbidity, estimated by using an age-adjusted score, has a critical impact on the postoperative course following emergency surgery for cIAI. Early assessment and management of patient’s comorbidity is mandatory at emergency setting
Follow-up of a new titanium-coated polyetheretherketone cage for the cervical spine
Poly-ether-ether-ketone (PEEK) cages have lower modulus of elasticity when compared with Titanium (TTN) cages. This suggests that PEEK-cages could show a lower rate of subsidence after anterior cervical discectomy-fusion (ACDF) and might lead to a lower loss of correction. We investigated the one to five year-results of standalone PEEK-TTN-porous coated cages in a patient cohort from 2014 to 2017. The patients underwent single-level ACDF for disc herniation and degenerative discopathy. Clinical and radiological outcome were assessed in 50 eligible patients after a mean of 27 months. Results: Solid arthrodesis was found in 84%. Neck disability index (NDI), and visual analogue scale (VAS) of neck and arm show comparable results to the literature. Conclusions: Clinical and radiological outcomes of ACDF with PEEK-body-cages with a porous coated surface show good bony integration. The modulus of elasticity, design, shape, size, cage surface architecture, as well as bone density, endplate preparation, radical microdiscectomy and distraction during surgery should be considered as important factors influencing the clinical results. One main advantage, over titanium cages, is the absence of MRI artifacts, allowing an excellent postoperative follow-up. inferior clinical outcome compared with bone grafts due to a higher elasticity modulus, which could result in cage subsidence.8 Nevertheless, due to structural properties, TTN implants are likely to provide a good osseo-integration9 and several clinical studies demonstrate successful results after implantation of TTN-cages.10-13 PEEKcages have a modulus of elasticity closely resembling that of cortical bone, which might lead to advantages in load sharing and stress distribution. This might reduce the subsidence rate with an improved segmental correction in the long term and a potentially higher fusion rate.14-16 A direct comparison of cervical TTNand PEEKcages in a clinical setting is very rarely found in the literature, 16, 17 and even less studies consequently compare the radiological results.16, 17 The latter studies showed the PEEK-implants being superior in maintaining cervical interspace height and achieving radiographic fusion, 16, 17 even suggesting to cease the application of TTN-cages in cervical spine surgery.16 A solution in-between are newer cages that combine the benefit of both materials: PEEK-body cages plasma-sprayed with a porous titanium surface which is tightly bonded to the PEEK surface.18, 19 On TTN alloy substrates, osteoblasts exhibit a more differentiated phenotype and increased bone morphogenetic protein production than on poly-ether-ether-ketone.20 A group of Japanese surgeons found that TTN-coated PEEK cages exhibit radiographic signs of bone on-growth, as represented by vertebral cancellous condensation around the cage, compared with that around the uncoated PEEK cage.21 Therefore, a TTN-coated PEEK cage may have the potential to promote solid fusion and to improve clinical outcomes in cervical interbody fusion surgery. This keeps the ideal elasticity modulus close to a bonelike elasticity modulus and offers a highly biocompatible surface that is well tolerated by bone and allows its ongrowth to the porous surface. The aim of the present study is to assess clinical and radiological results of CeSpace XP®, a titanium-coated PEEK cage
La Sociedad del Conocimiento en el entorno europeo y latinoamericano: el caso de Ecuador y España
El objetivo de esta investigación es la revisión y estudio de caso de las actuales Políticas de Información en España y América Latina, en concreto el caso de República de Ecuador, cuya situación demuestra una clara inversión en la evolución hacia la Sociedad del Conocimiento. Se analizan los principales planes de actuación estatales, así como aquellos patrones de medición basados en indicadores partiendo de las premisas sociales de ambos países. La metodología elegida se sustenta en el análisis de contenido de las políticas y de las principales entidades que las fomentan; asimismo, tiene un carácter prospectivo, dado que se intenta poner el foco en posibles perspectivas de actuación, gracias a una herramienta de evaluación DAFO que establece no solo diagnósticos de presente sino posibles rutas para el futuro
Aplicando PageRank en registros de actividades criminales : Una aproximación a la detección de bandas delictivas
Se presenta el resultado del estudio de las técnicas y metodologías actuales de análisis inteligente de datos y visualización para la asistencia en la investigación criminal, a partir de los registros de actividades delictivas, sus autores y las relaciones de datos que puedan derivarse a partir de ellas. Es de especial inter´es la identificación de bandas delictivas o criminales para propender a una persecución penal inteligente. Se discute el desarrollo de un componente de software para la visualización, incorporando la utilización del algoritmo de PageRank y detección de comunidades.XV Workshop Innovación en sistemas de Software (WISS)Red de Universidades con Carreras en Informátic
Madera enigmática y primera evidencia de tetrápodos en Formación Yaguarí (Pérmico medio-superior), Uruguay
This article describes an intriguing fossil material recently found in the fine-grained sandstone levels from the upper section of the Yaguarí Formation of Uruguay. The nature of this specimen and its relationships were, initially, not easy to determine with confidence although it was subjected to several analyses, such as morphological and comparative examination complemented with preparation of thin sections and microanatomical and chemical studies under SEM. However, the anatomical structure shown in the performed transversal thin sections allowed solving the issue on the different animal or plant interpretations of the fossil specimen, which was finally discerned in favor of the latter. Therefore, after a detailed comparative study of the thin sections, we concluded that the specimen is a wood fragment related to the Dadoxylon-Araucarioxylon complex. Moreover, in order to provide a better biostratigraphic calibration for these deposits until now devoid of fossils, we include a preliminary description of recently found fossil footprints, which represent the first evidence of the presence of tetrapods in levels of the Yaguarí Formation (sensu Elizalde et al., 1970), below the conglomerates that have yielded the Colonia Orozco Fauna. The footprints were preliminary assigned to the ichnotaxa cf. Karoopes isp, cf. Capitosauroides isp., and cf. Pachypes isp., suggesting the presence of gorgonopsids and therocephalian therapsids and pareiasauromorphs, respectively. The Middle-Late Permian age recently suggested for the Yaguarí Formation based on paleomagnetic and radioisotopic studies is here supported by the described fossils, which thus constitute preliminary but nonetheless relevant discoveries for deposits whose fossiliferous potential has yet to be explored.Este artículo describe un intrigante fósil recientemente descubierto en niveles de areniscas finas a medias de la sección superior de la Formación Yaguarí de Uruguay. La naturaleza y las afinidades de este espécimen no fueron inicialmente fáciles de determinar, a pesar de ser sometido a numerosos estudios, incluido un análisis anatómico-comparativo complementado con la preparación de secciones delgadas y análisis de su microestructura bajo Microscopio Electrónico de Barrido. La microestructura mostrada por las láminas delgadas en corte transversal permitió finalmente resolver el problema sobre discernir entre una naturaleza animal o vegetal del espécimen, siendo la última la aceptada. El detallado estudio comparativo de las secciones delgadas reveló que el espécimen es un fragmento de madera relacionado al complejo Dadoxylon-Araucarioxylon. Asimismo, para proveer una mejor calibración temporal de los depósitos de la sección superior de la Formación Yaguarí (Miembro Villa Viñoles), también se incluye en este trabajo una descripción preliminar de huellas de tetrápodos recientemente halladas en esta unidad, las cuales representan la primera evidencia de la presencia de tetrápodos en niveles de la Formación Yaguarí (sensu Elizalde et al., 1970) subyacentes a los conglomerados portadores de la Fauna de Colonia Orozco. Las huellas fueron asignadas a los icnotaxa cf. Karoopes isp., cf. Capitosauroides isp. y cf. Pachypes isp., sugiriendo la presencia de terápsidos gorgonópsidos y therocefalidos y de pareiasauromorfos, respectivamente. La edad Pérmico Medio a Tardío recientemente sugerida para la Formación Yaguarí, basado en estudios de paleomagnetismo sustentados por dataciones radioisotópicas, es congruente con la aportada por los fósiles aquí descriptos, que, aunque fragmentarios, constituyen descubrimientos preliminarmente relevantes para depósitos cuyo potencial fosilífero no ha sido aún explorado.CSIC: I+D 2016_24
Optimal design of irrigation network shifts and characterization of their flexibility
[EN] In this contribution, a nonlinear programming genetic hybrid algorithm for the optimal design of pressurized irrigation networks operating in shifts is presented, and an indicator is implemented to evaluate the flexibility of the resulting designs of the hybrid algorithm. The main objective is the minimization of the economic cost of the pipe network and the evaluation of the flexibility of the system designs. The research considers the allocation of shifts to the irrigation outlets (hydrants) and the sizing of the pipes as decision variables to reduce implementation costs. With the results of the optimization, the flexibility of the hydraulic network is analysed based on the random reassignment of shifts to the hydrants, which simulates the modifications that may occur during network operation. To validate the algorithm, once calibrated, it was applied to the design of four real irrigation sectors of Ecuador and Spain. The results indicate that the designs obtained improve in cost and flexibility with respect to those found with the traditional algorithm of the Economic Series, and that the assignment of the shifts is of utmost importance to minimize investment costs in pipes. At the same time, it constitutes a determining factor in the flexibility of the system[ES] En esta contribución se presenta un algoritmo híbrido genéticoprogramación no lineal para el diseño óptimo de redes presurizadas de
riego operando a turnos, y se implementa un indicador para evaluar la
flexibilidad de los diseños resultantes del algoritmo híbrido. El objetivo
principal es la minimización del costo económico de la red de tuberías y
la evaluación de la flexibilidad de los diseños del sistema. La
investigación considera como variables de decisión la asignación de
turnos a las tomas de riego (hidrantes) y el dimensionado de las
conducciones para reducir los costos de implementación. Con los
resultados de la optimización se analiza la flexibilidad de la red
hidráulica con base en la reasignación aleatoria de turno a los hidrantes,
que simula las modificaciones susceptibles de ocurrir durante la
explotación de la red. Para validar el algoritmo, una vez calibrado, éste
fue aplicado al diseño de cuatro sectores de riego reales de Ecuador y
España. Los resultados indican que los diseños obtenidos mejoran en
costo y flexibilidad respecto a los encontrados con el algoritmo
tradicional de la serie económica, y que la asignación de los turnos es de
suma importancia para minimizar los costos de inversión en tuberías, lo que a la vez constituye un factor determinante en la flexibilidad del
sistemaLapo P., CM.; Pérez-García, R.; Aliod-Sebastián, R.; Martínez-Solano, FJ. (2020). Diseño óptimo de redes de riego a turnos y caracterización de su flexibilidad. Tecnología y Ciencias del Agua (Online). 11(1):266-314. https://doi.org/10.24850/j-tyca-2020-01-07S26631411
Asymmetric cell division requires specific mechanisms for adjusting global transcription
Most cells divide symmetrically into two approximately identical cells. There are many examples, however, of asymmetric cell division that can generate sibling cell size differences. Whereas physical asymmetric division mechanisms and cell fate consequences have been investigated, the specific problem caused by asymmetric division at the transcription level has not yet been addressed. In symmetrically dividing cells the nascent transcription rate increases in parallel to cell volume to compensate it by keeping the actual mRNA synthesis rate constant. This cannot apply to the yeast Saccharomyces cerevisiae, where this mechanism would provoke a never-ending increasing mRNA synthesis rate in smaller daughter cells. We show here that, contrarily to other eukaryotes with symmetric division, budding yeast keeps the nascent transcription rates of its RNA polymerases constant and increases mRNA stability. This control on RNA pol II-dependent transcription rate is obtained by controlling the cellular concentration of this enzyme
Human prefoldin modulates co-transcriptional pre-mRNA splicing.
Prefoldin is a heterohexameric complex conserved from archaea to humans that plays a cochaperone role during the co-translational folding of actin and tubulin monomers. Additional functions of prefoldin have been described, including a positive contribution to transcription elongation and chromatin dynamics in yeast. Here we show that prefoldin perturbations provoked transcriptional alterations across the human genome. Severe pre-mRNA splicing defects were also detected, particularly after serum stimulation. We found impairment of co-transcriptional splicing during transcription elongation, which explains why the induction of long genes with a high number of introns was affected the most. We detected genome-wide prefoldin binding to transcribed genes and found that it correlated with the negative impact of prefoldin depletion on gene expression. Lack of prefoldin caused global decrease in Ser2 and Ser5 phosphorylation of the RNA polymerase II carboxy-terminal domain. It also reduced the recruitment of the CTD kinase CDK9 to transcribed genes, and the association of splicing factors PRP19 and U2AF65 to chromatin, which is known to depend on CTD phosphorylation. Altogether the reported results indicate that human prefoldin is able to act locally on the genome to modulate gene expression by influencing phosphorylation of elongating RNA polymerase II, and thereby regulating co-transcriptional splicing.Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación [BFU2016-77728-C3-1-P to S.C. and BFU2017-85420-R to J.C.R.] co-financed with European Union funds (FEDER); Andalusian Government [P12-BIO1938MO, BIO271, US-1256285 to S.C., BIO321 to J.C.R.]; Junta de Andalucía (to L.P.-B.). Funding for open access charge: Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación [BFU2016-77728-C3-1-P]
Human prefoldin modulates co-transcriptional pre-mRNA splicing
Trabajo presentado en el IV Meeting RNALife, celebrado en Sevilla (España) del 12 al 13 de julio de 2021.Prefoldin is a heterohexameric complex conserved from archaea to humans that plays a co-chaperone role during the co-translational folding of actin and tubulin monomers. Additional functions of prefoldin have been described, including a positive contribution to transcription elongation and chromatin dynamics in yeast. Here we show that prefoldin perturbations provoked transcriptional alterations across the human genome. Severe pre-mRNA splicing defects were also detected, particularly after serum stimulation. We found impairment of co-transcriptional splicing during transcription elongation, which explains why the induction of long genes with a high number of introns was affected the most. We detected genome-wide prefoldin binding to transcribed genes and found that it correlated with the negative impact of prefoldin depletion on gene expression. Lack of prefoldin caused global decrease in Ser2 and Ser5 phosphorylation of the RNA polymerase II carboxy-terminal domain. It also reduced the recruitment of the CTD kinase CDK9 to transcribed genes, and the association of splicing factors PRP19 and U2AF65 to chromatin, which is known to depend on CTD phosphorylation. Altogether the reported results indicate that human prefoldin is able to act locally on the genome to modulate gene expression by influencing phosphorylation of elongating RNA polymerase II, and thereby regulating co-transcriptional splicing
Diseño cinemático de un robot paralelo 2-PRR
Este artículo presenta una síntesis dimensional para un robot plano paralelo 2-PRR con estructura simétrica. Este robot posibilita la translación de la mesa móvil sin cambios en la orientación, lo cual resulta útil en aplicaciones que requieren posiciones controladas con alta rigidez. Debido a la alta sensibilidad que tienen estos robots con respecto a los cambios geométricos, muchas metodologías han sido desarrolladas para establecer la síntesis dimensional. En este trabajo se usó el Método de Normalización de Parámetros Finitos (PFNM) para establecer las dimensiones usando dos atlas de diseño, para el Índice Globales de Condición (GCI), y para el espacio de trabajo ( ). Se muestra que, para los dos atlas de diseño, GCI y , no es posible maximizar uno de los índices sin disminuir el otro, lo que representa un compromiso de diseño. Igualmente, se resaltan configuraciones singulares que vienen de geometrías especificas o de posiciones limite. La síntesis dimensional completa del 2-PRR es también presentada.In civil construction Abstract— This paper presents a dimensional synthesis for a 2-PRR planar parallel robot with a structural plane of symmetry. This robot can achieve the translation of the moving platform without changing the orientation, being useful for applications that require controlled positions with high rigidity. Because the performance of parallel robots is highly sensitive to their geometric parameters, many methodologies to state the dimensional synthesis has been developed. We used the method of Parameter - Finiteness Normalization Method (PFNM) to state the dimensional synthesis using Global Condition Index (GCI) and workspace ( ) design atlases. For the two, GCI and , designed atlases, it is not possible to maximize one of the indexes without diminishing the other one, which represents a design compromise. Also, we remark singular configurations that are coming from specific geometry or limit positions. The complete dimensional synthesis is also presented
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