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Ultra-Clean-Air (UCA) operating theatres aim to minimise surgical instrument contamination and wound infection through high flow rates of ultra-clean air, reducing the presence of Microbe Carrying Particles (MCPs). This study investigates the airflow patterns and ventilation characteristics of a UCA operating theatre (OT) under standard ventilation system operating conditions, considering both empty and partially occupied scenarios. Utilising a precise computational model, quasi-Direct Numerical Simulations (qDNS) were conducted to delineate flow velocity profiles, energy spectra, distributions of turbulent kinetic energy, energy dissipation rate, local Kolmogorov scales, and pressure-based coherent structures. These results were also complemented by a tracer gas decay analysis following ASHRAE standard guidelines. Simulations showed that contrary to the intended laminar regime, the OT's geometry inherently fosters a predominantly turbulent airflow, sustained until evacuation through the exhaust vents, and facilitating recirculation zones irrespective of occupancy level. Notably, the occupied scenario demonstrated superior ventilation efficiency, a phenomenon attributed to enhanced kinetic energy induced by the additional obstructions. The findings underscore the critical role of UCA-OT design in mitigating MCP dissemination, highlighting the potential to augment the design to optimise airflow across a broader theatre spectrum, thereby diminishing recirculation zones and consequently reducing the propensity for Surgical Site Infections (SSIs). The study advocates for design refinements to harness the turbulent dynamics beneficially, steering towards a safer surgical environment.

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BACKGROUND: Ventricular shunts are one of the most frequent techniques used for the management of hydrocephalus. The ventriculoperitoneal shunt (VPS) is the most commonly performed procedure, and the ventriculoatrial shunt (VAS) is the second option in most medical centers. The main objective of this study is to introduce and describe a surgical approach for VAS outlining our experience and comparing it with traditional shunting techniques. METHODS: In this retrospective cohort comparison study, we included patients with hydrocephalus treated with a surgical procedure between January 2010 and February 2021 at a single academic institution. We categorized the procedures into two groups: patients with VPS and conventional VAS grouped together into the conventional technique (CT) group, and the second group was patients with whom we performed VAS with complete internal jugular vein occlusion (IJVOT). We compared the surgical time, postoperative complications, and occurrence of shunt failure among the groups by performing univariate analysis using the Fisher exact test. RESULTS: Out of the 106 patients included in the analysis, IJVOT was performed in 66 patients, and CT in 40 patients. The median surgical time was 60 min (IQR 60-90) for IJVOT versus 100 min (IQR 60-120) for CT (p < 0.01). In the follow-up a month after the procedure, 83.3% of patients with IJVOT and 62.5% of patients with CT did not require shunt removal or shunt revision (p < 0.01). Shunt revision rates were 12.5% and 1.5% for CT while 1.5% and 2.5% for IJVOT at 1 and 6 months after the procedure. CONCLUSION: Our findings demonstrate that VAS with IJVOT is a safe method that exhibited shorter surgical times and outcomes comparable to CT. However, since the present study represents the first cohort evaluating IJVOT, it is imperative to conduct larger prospective studies, along with clinical trials, to fully explore and establish efficacy, long-term outcomes, and an in-depth comparison among shunting techniques.

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Introducción: Las radiografías dentales son una de las exposiciones médicas más frecuentes a la radiación ionizante. El uso de radiación ionizante está asociado a un riesgo probable de desencadenar efectos biológicos adversos y posibles daños a la salud del paciente. Para evitar que los pacientes reciban dosis innecesariamente altas durante estas exposiciones, la Comisión Internacional de Protección Radiológica recomienda la utilización de los niveles de referencia para diagnóstico, como una herramienta efectiva de ayuda a la optimización de la protección radiológica de los pacientes. Objetivo: Estimar los niveles de referencia para diagnóstico en radiografía dental intraoral y panorámica en la ciudad de Bogotá, D. C. Metodología: Se evaluaron los parámetros de exposición radiográficos de los equipos y la calidad de imagen en 68 equipos de radiografía dental periapical y 23 equipos de radiografía panorámica. Se estimaron las magnitudes dosimétricas de kerma incidente en aire (Kai) en equipos intraorales para la radiografía de un maxilar molar de un adulto y el producto kerma aire-área (PKA) en equipos de radiografía panorámica en un examen de un adulto estándar. Resultados: El tercer cuartil de la distribución de kerma incidente en aire para radiografía intraoral fue de 3,3 mGy y del producto kerma aire-área para radiografía panorámica fue de 103,9 mGycm2. En la distribución de frecuencias de kerma incidente en aire para radiografía intraoral, el porcentaje más alto de equipos estuvo en el rango de 2,0-3,0 mGy. En la distribución de frecuencias del producto kerma aire-área para los equipos de radiografía panorámica, el porcentaje más alto de equipos estuvo en el rango de 60 a 80 mGycm2. Discusión: Las instituciones consideradas para establecer los Niveles de Referencia para Diagnóstico en este estudio contaron con una adecuada calidad de la imagen evaluada con un maniquí dental, pero las variaciones en las dosis de radiación entre instituciones señalan la necesidad de implementar herramientas que contribuyan a la optimización de las prácticas. Conclusiones: Se recomienda usar los valores de los niveles de referencia para diagnóstico encontrados en esta investigación para optimizar la protección radiológica en las exposiciones radiológicas dentales, y se espera que este estudio sirva de base para nuevas investigaciones en las demás ciudades del país.

Introduction: Dental X-rays are one of the most frequent medical exposures to ionizing radiation. The use of ionizing radiation is associated with a probable risk of triggering adverse biological effects and possible damage to the patient's health. To prevent patients from receiving unnecessarily high doses during these exposures, the International Commission on Radiological Protection recommends the use of diagnostic reference levels as an effective tool to help optimize radiological protection for patients. Objective: To estimate diagnostic reference levels in intraoral and panoramic dental radiography in the city of Bogotá, D.C. Methodology: In 68 periapical dental radiography equipment and 23 panoramic radiography equipment, the radiographic exposure parameters of the equipment and image quality were evaluated. The dosimetric magnitudes of incident air kerma (Ka,i) in intraoral equipment for the radiography of a maxillary molar of an adult and the air kerma-area product (PKA) in panoramic radiography equipment in a standard adult examination were estimated. Results: The third quartile of the incident air kerma distribution for intraoral radiography was 3,3 mGy and the air kerma-area product for panoramic radiography was 103,9 mGycm2. In the frequency distribution of incident air kerma for intraoral radiography, the highest percentage of equipment was in the range of 2,0-3,0 mGy, and in the frequency distribution of the air kerma-area product for equipment of panoramic radiography, the highest percentage of the equipment was in the range of 60 to 80 mGy cm2. Discussion: The institutions considered to establish the diagnostic reference levels in this study had an adequate quality of the image evaluated with a dental phantom, but the variations in radiation doses between institutions indicate the need to implement tools that contribute to the optimization of the practices. Conclusions: It is recommended to use the values of the diagnostic reference levels found in this research to optimize radiological protection in dental radiological exposures, and it is expected that this study will serve as a basis for further research in other cities of the country.

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Bothrops atrox snakebites are a relevant problem in the Amazon basin. In this biodiverse region, the ethnomedicinal approach plays an important role as an alternative to antivenom therapy. Urospatha sagittifolia (Araceae) is a plant used for this purpose; however, its neutralizing properties have not been scientifically accessed. To fill this gap, we investigated the ability of U. sagittifolia to modulate the catalytic activity of Bothrops atrox venom, and their toxic consequences, such as local damage and lethality. The venom profile of B. atrox was assessed by chromatography and electrophoresis. Inhibition of the three main enzymatic and medically important toxins from the venom was evaluated using synthetic substrates and quantified by chromogenic activity assays. Additionally, the neutralization of lethality, hemorrhage and edema were investigated by in vivo assays. The possible interactions between venom proteins and plant molecules were visualized by polyacrylamide gel electrophoresis. Finally, the phytochemical constituents present in the ethanolic extract were determined by qualitative and quantitative analyses. The ethanolic extract reduced the activity of the three main enzymes of venom target, achieving ranges from 19% to 81% of inhibition. Our in vivo venom neuralizations assays showed a significant inhibition of edema (38.72%) and hemorrhage (42.90%). Additionally, lethality was remarkably counteracted. The highest extract ratio evaluated had a 75% survival rate. Our data support the biomedical value of U. sagittifolia as a source of natural enzyme inhibitors able to neutralize catalytically active B. atrox venom toxins and their toxic effects.

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La artrografía, a pesar de ser una técnica antigua, ha recobrado validez en los últimos años por su utilidad en la evaluación de estructuras que no se pueden valorar correctamente mediante técnicas de imagen no invasivas. El propósito de este artículo es realizar una revisión de las técnicas de artrografía por fluoroscopia de las principales articulaciones en las extremidades (hombro, codo, muñeca, cadera, rodilla y tobillo), con el fin de brindar al lector múltiples abordajes para cada una de ellas, con base en la anatomía articular.

Arthrography, despite being an old technique, has regained validity in recent years due to its usefulness in the assessment of structures that cannot be correctly assessed using non-invasive imaging techniques. The purpose of this article is to review the fluoroscopic arthrography techniques of the main joints in the extremities (shoulder, elbow, wrist, hip, knee and ankle), in order to provide the reader with multiple approaches for each of them, based on articular anatomy.

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Resumen Gracias a su débil polaridad y gran área superficial, los soportes de carbón activado tienen el potencial de aumentar la dispersión de los sulfuros metálicos. La ausencia de una interacción fuerte metal-soporte puede conducir a la formación de una fase Ni-Mo-S muy activa y estable. En este estudio se prepararon catalizadores por el método de co-impregnación, con diferentes cantidades de níquel y molibdeno y soportados sobre carbón activado comercial, y se caracterizaron por técnicas BET, XRF y SEM. Se evaluó su actividad catalítica para el hidroprocesamiento de aceite de Jatropha utilizando un reactor por lotes, y se determinó la composición de los productos líquidos y gaseosos. Los resultados mostraron que los productos gaseosos están compuestos principalmente de grandes cantidades de propano y pequeñas cantidades de otros hidrocarburos livianos (C1 a C5). Los hidrocarburos líquidos fueron principalmente una mezcla de n-parafinas de C15-C18 y de algunos compuestos oxigenados. Los catalizadores presentaron una fracción de masa de 3 % Ni, 15 % Mo (Ni3Mo15/AC) y mayor selectividad hacia hidrocarburos C17-C18, con una distribución de productos similar al catalizador Ni-Mo-S soportado en alúmina comercial.

Abstract Due to their weak polarity and large surface area, activated carbon supports have the potential to enhance the dispersion of metal-sulfides. It is expected that the absence of a strong metal-support interaction can result in the formation of a very active and stable Ni-Mo-S phase. In this study, catalysts with different amounts of nickel and molybdenum supported on a commercial activated carbon were prepared by a co-impregnation method and characterized by BET, XRF, and SEM techniques. The catalytic activity for hydroprocessing of Jatropha oil was evaluated in a batch reactor, and the composition of the liquid and gaseous products were determined. Results showed that gaseous products are mainly composed of high amounts of propane and small amounts of other light hydrocarbons (C1 to C5). Liquid hydrocarbon products consisted of a mixture containing mainly n-paraffins of C15-C18 and some oxygenated compounds. The catalysts with a mass fraction of 3 % Ni, 15 % Mo (Ni3Mo15/AC) presented the highest selectivity toward C17-C18 hydrocarbons, with a product distribution similar to a commercial alumina-supported Ni-Mo-S catalyst.

Resumo Devido a sua baixa polaridade e amplia área superficial, os suportes de carvão ativado possuem o potencial de aumentar a dispersão de sulfetos metálicos. A ausência de uma forte interação suporte-metal pode levar a formação de uma fase Ni-Mo-S muito ativa e estável. Neste estudo, foram preparados catalizadores com diferentes teores de níquel e molibdênio suportados em carvão ativado comercial por um método de co-impregnação e caracterizados pelas técnicas BET, XRF e SEM. A atividade catalítica foi avaliada para o hidroprocessamento do óleo de Jatropha em um reator por lotes, e se determinou a composição dos produtos líquidos e gasosos. Os resultados mostraram que os produtos gasosos são compostos principalmente por altos teores de propano e pequenos teores de outros hidrocarbonos leves (C1-C5). Os hidrocarbonos líquidos consistiram de uma mistura contendo principalmente n-parafinas de C15-C18 e alguns compostos oxigenados. Os catalizadores apresentaram uma fração de massa de 3 % Ni, 15 % Mo (Ni3Mo15/AC) e uma maior seletividade em relação aos hidrocarbonos C17-C18, com uma distribuição de produtos similar ao catalizador comercial Ni-Mo-S suportado em alumina.

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A comprehensive study of acetylene adsorption on δ-MoC(001), TiC(001) and ZrC(001) surfaces was carried out by means of calculations based on periodic density functional theory, using the Perdew-Burke-Ernzerhof exchange-correlation functional. It was found that the bonding of acetylene was significantly affected by the electronic and structural properties of the carbide surfaces. The adsorbate interacted with metal and/or carbon sites of the carbide. The interaction of acetylene with the TiC(001) and ZrC(001) surfaces was strong (binding energies higher than -3.5 eV), while moderate acetylene adsorption energies were observed on δ-MoC(001) (-1.78 eV to -0.66 eV). Adsorption energies, charge density difference plots and Mulliken charges suggested that the binding of the hydrocarbon to the surface had both ionic and covalent contributions. According to the C-C bond lengths obtained, the adsorbed molecule was modified from acetylene-like into ethylene-like on the δ-MoC(001) surface (desired behavior for hydrogenation reactions) but into ethane-like on TiC(001) and ZrC(001). The obtained results suggest that the δ-MoC(001) surface is expected to have the best performance in selective hydrogenation reactions to convert alkynes into alkenes. Another advantage of δ-MoC(001) is that, after C2H2 adsorption, surface carbon sites remain available, which are necessary for H2 dissociation. However, these sites were occupied when C2H2 was adsorbed on TiC(001) and ZrC(001), limiting their application in the hydrogenation of alkynes.

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Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae) in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase (COI) I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n=179) is presented for the first time in 60 years.

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Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae) in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase ( COI ) I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n = 179) is presented for the first time in 60 years.

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