384 research outputs found
Trichomycterus rosablanca (Siluriformes, Trichomycteridae) una especie nueva de bagre hipogeo de los Andes colombianos
Trichomycterus rosablanca is described as a new troglobitic catfish species from caves in southeastern Santander, Colombia. These caves are drained by the Carare River of the Magdalena River basin. The new species is characterized by the advanced condition in the typical troglomorphisms found in other congeneric cave-dwelling species, such as absence of eyes and pigmentation. Trichomycterus rosablanca is diagnosed by the following putative autapomorphies: 1) presence of a circular foramen in the main body of the interopercle, dorsal to the interopercular plate supporting the odontodes, and 2) presence of a single sensory pore in the posteriormost section of the infraorbital canal. Trichomycterus rosablanca can be distinguished from all known Trichomycterus species from Colombia by having the supraorbital canal interrupted in the nasal section, resulting in the pattern of s1, s2, s3, and s6 sensory pores, and the lachrimal/antorbital bone not enclosing the anteriormost section of the infraorbital canal. The genetic distinctiveness of Trichomycterus rosablanca is confirmed by GMYC and genetic distance method analyses of the cytochrome C oxidase subunit I gene sequence. The description of this species places Colombia as the second most diverse country in the continent in terms of number of cave fish species and calls the attention on the conservation efforts needed to guarantee the permanence of this remarkable diversity of hypogean fishes. Se describe Trichomycterus rosablanca, una especie nueva de bagre troglobio de cuevas en el suroriente de Santander, Colombia. Estas cuevas son drenadas por el río Carare, de la cuenca del río Magdalena. La especie nueva se caracteriza por la condición avanzada en los troglomorfismos típicos encontrados en otros congéneres habitantes de cuevas, como ausencia de ojos y pigmentación. Trichomycterus rosablanca es diagnosticado por las siguientes autapomorfías putativas: 1) presencia de un foramen circular enel cuerpo principal del interopérculo, dorsal a la placa interopercular soportando los odontodes, y 2) presencia de un único poro sensorial en la sección más posterior del canal infraorbital. Trichomycterus rosablanca puede ser distinguida de todas las especies conocidas de Trichomycterus de Colombia por tener el canal supraorbital interrumpido en la sección nasal, resultando en el patrón de poros sensoriales s1, s2, s3 y s6 y el hueso lacrimal/antorbital no encerrando la sección más anterior del canal infraorbital. La identidad genética de Trichomycterus rosablanca es confirmada por análisis GMYC y de distancia genética de la secuencia génica de la subunidad I de la citocromo C oxidasa. La descripción de esta especie ubica a Colombia como el segundo país más diverso en el continente en términos del número de especies de peces cavernícolas y llama la atención sobre los esfuerzos de conservación necesarios para garantizar la permanencia de esta extraordinaria diversidad de peces hipogeos
Use of Distributed Temperature Sensing Technology to Characterize Fire Behavior
We evaluated the potential of a fiber optic cable connected to distributed temperature sensing (DTS) technology to withstand wildland fire conditions and quantify fire behavior parameters. We used a custom-made ‘fire cable’ consisting of three optical fibers coated with three different materials—acrylate, copper and polyimide. The 150-m cable was deployed in grasslands and burned in three prescribed fires. The DTS system recorded fire cable output every three seconds and integrated temperatures every 50.6 cm. Results indicated the fire cable was physically capable of withstanding repeated rugged use. Fiber coating materials withstood temperatures up to 422 °C. Changes in fiber attenuation following fire were near zero (−0.81 to 0.12 dB/km) indicating essentially no change in light gain or loss as a function of distance or fire intensity over the length of the fire cable. Results indicated fire cable and DTS technology have potential to quantify fire environment parameters such as heat duration and rate of spread but additional experimentation and analysis are required to determine efficacy and response times. This study adds understanding of DTS and fire cable technology as a potential new method for characterizing fire behavior parameters at greater temporal and spatial scales
Active Disturbance Rejection Control for Robot Manipulator
Active Disturbance Rejection Control (ADRC) is a control methodology used in chemical processes, aircraft, motors, and other systems. This paper compares the results of an ADRC controller to a Proportional Integral Derivative controller (PID), applied to two degrees of freedom robots. A Linear Extended State Observer (LESO) is used to reconstruct the state variables and unknown parameters needed to control the position of each link. The ADRC can achieve the tracking position and estimate the velocity of each link. The results of the simulation program are shown
Morbilidad Asistida y morbilidad real por infecciones respiratorias agudas
ResumenEl presente trabajo aborda el estudio de la morbilidad por Infecciones Respiratorias Agudas (IRA) en áreas del municipio Lisa en Ciudad Habana, así como en localidades del municipio Isla de la Juventud (Cuba), con objeto de caracterizar algunos aspectos de la morbilidad por demanda de consultae identificar la morbilidad real. Alrededor del 90% de las consultas por IRA fueron por primera vez y en general la razón de éstas, respecto al seguimiento fue de 5,3. A través de la búsqueda activa de enfermos se obtuvieron las tasas de morbilidad real (TMR) entre valores de 110,4 y 163,4 casos por 1000 habitantes, que fueron muy superiores a las tasas de morbilidad por demanda de consulta (TMDC) en iguales periodos de tiempo. Resultado de la división de ambas tasas se obtuvo el«índice de morbilidad real» (IMR) cuyo cociente osciló entre 5 y 15, aproximadamente. Una alta proporción (47,6%) de enfermos refirieron no haber solicitado atención médica. Estos resultados permiten hacer estimaciones aproximadas del comportamiento real de las IRA en el universo de estudio y establecer bases para un nuevo programa de control, perfeccionando ademcis la vigilancia epidemiolóigica en la atención primaria de salud.SummaryThe present work presents the study of morbidity due to acute respiratory infections (ARI) in areas of the town of Lisa in Ciudad Habana, and Isla Juventud (Cuba), to caracterise different aspects of morbidity measured by health care attendance and to measure true morbidity. About 90% of consultations for ARI were first-time consultations, while their ratio to further consultations was 5.3. True morbidity rates (TMR), obtained trough active research, ranged from 110.4 to 163.4 cases per 1000 inhabitants, considerably higher than morbidity rates measured by primary care consultations (MRPCC) in the same time period. The true morbidity index (TMI), as measured by the ratio of the two previous rates, ranged from 5 to 15. Ahigh proportion (47.6%) of cases reported no medical careattendance. These results provide approximate estimates of true morbidity in the study area, and allow the establishment of a new control program, also improving epidemiologic surveillance within primary care activities
Physicochemical and antimicrobial characterization of beeswax–starch food-grade nanoemulsions incorporating natural antimicrobials
Nanoemulsions are feasible delivery systems of lipophilic compounds, showing potential as edible coatings with enhanced functional properties. The aim of this work was to study the effect of emulsifier type (stearic acid (SA), Tween 80 (T80) or Tween 80/Span 60 (T80/S60)) and emulsification process (homogenization, ultrasound or microfluidization) on nanoemulsion formation based on oxidized corn starch, beeswax (BW) and natural antimicrobials (lauric arginate and natamycin). The response variables were physicochemical properties, rheological behavior, wettability and antimicrobial activity of BW–starch nanoemulsions (BW–SN). The BW–SN emulsified using T80 and microfluidized showed the lowest droplet size (77.6 ± 6.2 nm), a polydispersion index of 0.4 ± 0.0 and whiteness index (WI) of 31.8 ± 0.8. This BW–SN exhibited a more negative ζ-potential: −36 ± 4 mV, and Newtonian flow behavior, indicating great stability. BW–SN antimicrobial activity was not affected by microfluidization nor the presence of T80, showing inhibition of the deteriorative fungi R. stolonifer, C. gloeosporioides and B. cinerea, and the pathogenic bacterium S. Saintpaul. In addition, regardless of emulsifier type and emulsification process, BW–SN applied on the tomato surface exhibited low contact angles (38.5° to 48.6°), resulting in efficient wettability (−7.0 mN/m to −8.9 mN/m). These nanoemulsions may be useful to produce edible coatings to preserve fresh-produce quality and safety.We are grateful to CONACyT for PhD grant to Teresita Arredondo Ochoa, and financial support for project No. 166751. Special thanks are given to Alfonso Pérez for help on DSC analysis and Ma. Lourdes Palma Tirado for technical support on micrographs
Simulador de negocios CAPSIM: la industria de sensores y las estrategias de la empresa Chester
En este documento se reportan las especificaciones técnicas, decisiones, análisis y aprendizajes obtenidos en el simulador de negocios CAPSTONE. Se explica el entorno de competencia, las estrategias genéricas y se establece el perfil de la empresa Chester. Se define la identidad corporativa, los objetivos, la estrategia a seguir durante la competencia, así como los potenciales ajustes. Se explica lo ocurrido en cada uno de los periodos de competencia, desde el panorama general, las decisiones de producción, investigación y desarrollo, finanzas y mercadotecnia de cada una de las empresas, así como un análisis de los resultados y descripción de los errores, aciertos y ajustes a realizar
Water-Repellent Fluoropolymer-Based Coatings
We would like to thank to the company TECNIMACOR S.L. (Córdoba, Spain) for the preparation of the coatings studied in this work.Fluoropolymer-based coatings are widely used for release applications. However, these hydrophobic surfaces do not reveal a significantly low adhesion. Water repellency incorporated to fluoropolymer coatings might enhance their release performance. In this work, we focused on the surface texturing of a well-known polytetrafluoroethylene (PTFE)-based coating. We explored as texturing routes: sanding, sandblasting and laser ablation. We examined the surface roughness with white light confocal microscopy and the surface morphology with environmental scanning electron microscopy (ESEM). Water-repellent fluoropolymer coatings were reproduced in all cases, although with different degree, parametrized with bounces of water drops (4–5 μL). Laser ablation enabled the lowest adhesion of coatings with 24 ± 2 bounces. This result and the current development of laser patterning for industry assure the incipient use of laser ablation for release coatings.The research was funded by the projects MAT2014-60615-R and MAT2017-82182-R, funded by the Spanish Ministry of Economy and Competitiveness (MINECO-FEDER)
Identification of Potential Kinase Inhibitors within the PI3K/AKT Pathway of Leishmania Species
Leishmaniasis is a public health disease that requires the development of more effective treatments and the identification of novel molecular targets. Since blocking the PI3K/AKT pathway has been successfully studied as an effective anticancer strategy for decades, we examined whether the same approach would also be feasible in Leishmania due to their high amount and diverse set of annotated proteins. Here, we used a best reciprocal hits protocol to identify potential protein kinase homologues in an annotated human PI3K/AKT pathway. We calculated their ligandibility based on available bioactivity data of the reported homologues and modelled their 3D structures to estimate the druggability of their binding pockets. The models were used to run a virtual screening method with molecular docking. We found and studied five protein kinases in five different Leishmania species, which are AKT, CDK, AMPK, mTOR and GSK3 homologues from the studied pathways. The compounds found for different enzymes and species were analysed and suggested as starting point scaffolds for the design of inhibitors. We studied the kinases’ participation in protein–protein interaction networks, and the potential deleterious effects, if inhibited, were supported with the literature. In the case of Leishmania GSK3, an inhibitor of its human counterpart, prioritized by our method, was validated in vitro to test its anti-Leishmania activity and indirectly infer the presence of the enzyme in the parasite. The analysis contributes to improving the knowledge about the presence of similar signalling pathways in Leishmania, as well as the discovery of compounds acting against any of these kinases as potential molecular targets in the parasite.Fil: Ochoa, Rodrigo. Universidad de Antioquia; ColombiaFil: Ortega Pajares, Amaya. University of Melbourne; AustraliaFil: Castello, Florencia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; ArgentinaFil: Serral, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; ArgentinaFil: Fernández Do Porto, Darío Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Villa Pulgarin, Janny A.. Coorporación Universitaria Remington; ColombiaFil: Varela M., Rubén E.. Universidad Santiago de Cali; ColombiaFil: Muskus, Carlos. Universidad de Antioquia; Colombi
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