Synthetic cathinones are β-keto amphetamine derivatives whose appearance has increased dramatically in the past decades. N-Ethyl substituted cathinones have been proven to potently inhibit dopamine ...(DA) uptake and induce psychostimulant and rewarding effects in mice. However, little is known about the influence of the alpha-carbon side-chain length of N-ethyl cathinones on their pharmacological and toxicological effects. Thus, the aim of this study was to synthesize and investigate the in vitro and in vivo effects of five N-ethyl substituted cathinones: N-ethyl-cathinone (NEC), N-ethyl-buphedrone (NEB), N-ethyl-pentedrone, N-ethyl-hexedrone (NEH), and N-ethyl-heptedrone. HEK293 cells expressing the human DA or serotonin transporter (hDAT and hSERT) were used for uptake inhibition and binding assays. PC12 cells were used for the cytotoxicity assays. Swiss CD-1 mice were used to study the in vivo psychostimulant, anxiogenic, and rewarding properties. Our results show that all tested cathinones are able to inhibit DA uptake and are DAT-selective. The potency of DA uptake inhibitors increases with the elongation of the aliphatic side chain from methyl to propyl and decreases when increasing from butyl to pentyl, which correlates with an inverted U-shape psychostimulant response in mice at the medium dose tested. On the other hand, an increase in the α-carbon side-chain length correlates with an increase in the cytotoxic properties in PC12 cells, probably due to better membrane penetration. Moreover, all the cathinones tested have shown higher cytotoxicity than methamphetamine. Finally, our study not only demonstrated the rewarding properties of NEC and NEB but also the anxiety-like behavior induced at high doses by all the cathinones tested.
To investigate the effects of immediate start of norepinephrine versus initial fluid loading followed by norepinephrine on macro hemodynamics, regional splanchnic and intestinal microcirculatory ...flows in endotoxic shock.
Animal experimental study.
University translational research laboratory.
Fifteen Landrace pigs.
Shock was induced by escalating dose of lipopolysaccharide. Animals were allocated to immediate start of norepinephrine (i-NE) ( n = 6) versus mandatory 1-hour fluid loading (30 mL/kg) followed by norepinephrine (i-FL) ( n = 6). Once mean arterial pressure greater than or equal to 75 mm Hg was, respectively, achieved, successive mini-fluid boluses of 4 mL/kg of Ringer Lactate were given whenever: a) arterial lactate greater than 2.0 mmol/L or decrease less than 10% per 30 min and b) fluid responsiveness was judged to be positive. Three additional animals were used as controls (Sham) ( n = 3). Time × group interactions were evaluated by repeated-measures analysis of variance.
Hypotension was significantly shorter in i-NE group (7.5 min 5.5-22.0 min vs 49.3 min 29.5-60.0 min; p < 0.001). Regional mesenteric and microcirculatory flows at jejunal mucosa and serosa were significantly higher in i-NE group at 4 and 6 hours after initiation of therapy ( p = 0.011, p = 0.032, and p = 0.017, respectively). Misdistribution of intestinal microcirculatory blood flow at the onset of shock was significantly reversed in i-NE group ( p < 0.001), which agreed with dynamic changes in mesenteric-lactate levels ( p = 0.01) and venous-to-arterial carbon dioxide differences ( p = 0.001). Animals allocated to i-NE showed significantly higher global end-diastolic volumes ( p = 0.015) and required significantly less resuscitation fluids ( p < 0.001) and lower doses of norepinephrine ( p = 0.001) at the end of the experiment. Pulmonary vascular permeability and extravascular lung water indexes were significantly lower in i-NE group ( p = 0.021 and p = 0.004, respectively).
In endotoxemic shock, immediate start of norepinephrine significantly improved regional splanchnic and intestinal microcirculatory flows when compared with mandatory fixed-dose fluid loading preceding norepinephrine. Immediate norepinephrine strategy was related with less resuscitation fluids and lower vasopressor doses at the end of the experiment.
El género Isonychia agrupa efímeras con ninfas de gran tamaño presentes en ecosistemas lóticos. Este género tiene una distribución muy amplia, a pesar de ello, en México los registros son muy escasos ...y éstas no refieren las características ambientales de los sitios donde fueron encontradas. El objetivo de este trabajo es reportar por primera vez el género Isonychia en el estado de Durango, así como caracterizar algunos parámetros fisicoquímicos del agua asociados a su distribución. Se registraron 19 ninfas de Isonychia, que probablemente corresponden a la especie I. sicca, en siete sitios dentro de la cuenca del río Nazas. Esto amplía el rango de distribución del género Isonychia para México. Los ejemplares se registraron en ambientes con velocidad de corriente moderada y una calidad del agua aceptable en comparación con otros sistemas riparios, en términos de oxígeno disuelto, conductividad eléctrica, sólidos disueltos totales, pH, temperatura y amonio.
Este artículo tiene como objetivo proponer nuevos enfoques para interpretaciones e inferencias en los contextos arqueológicos de sitios al aire libre relacionados con grupos de cazadores-recolectores ...que ocuparon los ecosistemas de las sabanas neotropicales de los cerrados brasileños que, debido a la escasez de elementos que puedan corroborar la identificación y caracterización de una posible dinámica sociocultural en torno al uso de los recursos naturales, tienen sus modelos económicos y de subsistencia basados en analogías y correlaciones etnográficas. Desde la perspectiva de los estudios arqueológicos y etnoarqueológicos, proponemos el uso de analogías, correlaciones y discusiones con grupos contemporáneos, que utilizan los recursos naturales de los bosques como principal fuente de alimentación y materiales, como una forma de reconstruir dinámicas del pasado mediante la aplicación de modelos en arqueología. ENGLISH: This paper aims to propose new approaches for interpretations and inferences in the archaeological contexts of outdoor sites related to hunter-gatherer groups who occupied the ecosystems of the Brazilian Cerrado neotropical savannas which, due to the scarcity of elements that can corroborate the identification and characterization of a possible sociocultural dynamics around the use of natural resources, have their economic and subsistence models based on ethnographic analogies and correlations. From the perspective of archaeological and ethnoarchaeological studies, we propose the use of analogies, correlations and discussions with contemporary groups, using natural resources of the forests as their main source of food and materials, as a way to reconstruct past dynamics through the application of models in archaeology.
The Brazilian aviation sector aiming to reduce its greenhouse emissions up to 37% by 2030 and up to 43% by 2050 (compared to 2005) using alternative fuels. For this reason, the evaluation of ...potential feedstock was made for the biojet fuel production focused in the Brazilian context. Four biomass types were proposed (Sugarcane, Jatropha, Soybeans and Eucalyptus), considering three factors: feedstock abundance (without negative impact in population foods), advances in conversion technology, and blend limit already approved by the ASTM International for the use of biojet fuels into fossil jet fuel. Based on this study, it is concluded that Brazil has a great number of available lands for the culture of feedstock from which aviation alternative fuel can be produced, with possible substitution of up to 10% vol. Of fossil jet fuel consumed in the country. However, conversion technologies are still a challenge. Only, Synthetic Paraffinic Kerosene (SPK) obtained by both Fischer Tropsch (FT) process and Alcohol to Jet (ATJ) process offer competitive prices compared to petroleum-based jet fuel. Considering sugarcane as the main feedstock, a self-sustained integrated process was evaluated aiming to increase the production performance of biojet fuel. Four biojet fuels were obtained by this process (ATJ – SPK, FT – SPK, Farnesane and Hexanol), allowing the reduction of up to 19.16% in the number of cultivated lands for sugarcane and up to 56.12% for its forest residues. Finally, the payload versus range ratio was described using the Breguet range equation applied to a possible commercial flight, taking into account all biojet fuels produced from the proposed feedstock including their blends.
•Brazil has available lands for feedstock culture suitable for the production of aviationalternative fuels.•The sugarcane is the main feedstock for the biofuel production for aviation in integratedprocess mode.•The diversification in renewable fuels production contribute to reach greater substitution targets.•The conversion technologies Fischer-Tropsch (F-T) and Alcohol to Jet (ATJ) offerprices more competitive against conventional jet fuel.•Light biofuels and with calorific value lower than conventional jet fuel could be used inshort ranges without to sacrifice the payload.
Waste heat emissions derived from cooling systems of the thermal power plant often discharged into rivers, lakes and seas, have been the direct cause of environmental problems for marine life. To ...control these wastewater discharges into the receptor water body, government regulations have been created to act as limiting factors for additional power generation from these plants. The problem can be solved with an organic Rankine cycle (ORC), which is considered a promising technology in electricity generation and an alternative to avoid the thermal pollution of aquatic ecosystems. The present work analyzes the use of an ORC system aiming to increase the thermal and overall efficiency of conventional operating systems without causing an additional thermal impact on marine species. This evaluation was based on the first and second laws of thermodynamics, applied to seven organic fluids (toluene, methanol, benzene, R11, R12, R113, R134a) and equations that linked the overall efficiency of the power plant with parameters of life quality in the rivers. Results showed that among the chosen organic fluids benzene produced the highest thermal efficiency for the ORC. Besides, an application of the proposed modelling in a thermal power plant localized near to Tubarão river, SC – Brazil was presented. Results showed that by using R113 as working fluid, it is possible to generate up to 1365.02 kWelec of additional electrical energy and increase both thermal and overall efficiency of a thermal power plant by up to 22.34% and 11.01%, respectively, without causing a thermal impact on the aquatic ecosystem. The best energy use was achieved by the recuperative ORC configuration. The Dissolved Oxygen Concentration (DOC) was reduced to 6.14 %day−1, which is consistent with the regulation of the Brazilian government regarding effluent discharges in lagoons, rivers and seas. On the other hand, considering the electricity cost at 0.16 US$kWh−1 and 5% as an annual percentage rate (APR), results in a payback period of approximately 5.3 years. Thus, the specific investment cost (SIC) of this technology was estimated at 1314.57 US$kWe−1.
•Thermodynamic analysis of an ORC was carried out with seven organic fluids.•An overall efficiency increase of up to 11.01% was obtained by using an ORC system.•The water temperature is a fundamental parameter for aquatic ecosystems.•The Dissolved Oxygen Concentration Reduction (DOCR) was up to 6.14 %day−1 by using an ORC module.•Simplified economic analysis was included in this study.
One of the key aspects to keep adequate management and preservation of the built heritage is to maintain an adequate registry of the monuments. In many cases, state-of-the-art technologies are being ...used to develop accurate and rapid surveys, which utilize sophisticated high-cost equipment. However, in developing countries that possess a rich heritage, many of these technologies are beyond the reach of their possibilities, having to rely on manual, inefficient, and inaccurate systems that are still used.This research shows several alternatives of relatively low-cost techniques that allow a reliable data collection of built heritage, without losing the richness of the details of the historical architecture. To do this, a comparison is made between different methods of manual, semi-automatic, and automatic data collection, analyzing their costs and benefits. Subsequently, a comparative survey is carried out using the most efficient and affordable methods, proposing a methodology that leads to the improvement of surveys in historical buildings without this entailing a significant increase in costs.
•A detailed experimental procedure to estimate the LFLs of QAV – l/anhydrous ethanol blends was developed.•In less presence of molecules, LFLs are better estimated using Le Chatelier’s ruler.•Le ...Chatelier's ruler depends strongly on both nature of the fuel fluid and the size flammability chamber used.•LFLs are better estimated by Le Chatelier’s ruler when the mixture fuels are as homogeneous as possible.•The Chi-square test shows that there is a high probability that experimental data meet with the distributions proposed.
Anhydrous ethanol is an attractive alternative to be used as a substitute or additive in petroleum-based fuels aiming to ensure environmental sustainability. In Brazil, ethanol has been used as an alternative fuel in both road and air (agricultural airplanes) transport sectors. Due to that ethanol is volatile, therefore flammable in standard conditions, its explosive characteristics need to be investigated. In this work, it was made a detailed experimental assessment of Lower Flammability Limits (LFLs) from QAV – 1/anhydrous ethanol/air mixtures at different temperature and pressure conditions, where QAV – 1 is Jet fuel – A1. For the measures, it was used a flammability apparatus build according to American Standard ASTM E – 681. The experimental measures from mixtures both pure and binary were compared with the classical Le Chatelier's rule. Besides, two analytical expressions were proposed. One related to the stoichiometric concentration and another related to the specific states (geometrical approximation) of each fuel. The Absolute Relative Error (ARE) was used to identify the differences between the actual values and calculated values. However, to evaluate the goodness of fit of both distributions, two important statistic parameters were used, that is; the Average Absolute Relative Error (AARE) and Chi-Square test χ2 for the full observed data. The results have shown that, for different pressure conditions, the effect of temperature increase on the LFLs is slight in the range from 100 to 150 °C. Also, LFLs from binary blends depend strongly on both nature of fuels and the size of the combustion chamber used. Additionally, it was observed that Le Chatelier's rule applied to experimental data distribution is more adequate for the prediction of LFLs, improving in less presence of fuel molecules. Finally, it using the inductive method the causes for the ignition in the LFLs were identified.
This research project focuses on ethno-educational context, in which it is intended to make an echo in formal educative contexts, receding from institutional educational scenarios and emphasizes on ...how knowledge may flow at the core of this wayuu indigenous culture. Data collection process was done through context direct immersion by experiencing situations and interacting among adults and children on their daily life context. This process also aroused another research intention from this project, speeches’ transcripts and analysis from a linguistic established methodology of this fact. Research results realize the importance of dialogues and intergenerational interactions have inside the community, which from infancy early stages of life, contribute to the development and consolidation of the wayuu culture.
La investigación se centra en el contexto de la etnoeducación. Procura tener eco en contextos educativos formales, alejándose de escenarios educativos institucionales y centrándose en encontrar cómo transita el conocimiento en el interior de la cultura indígena wayuu. El proceso de recolección de datos se dio a partir de la inmersión directa en el contexto viviendo con ellos situaciones e interacciones reales de adultos y niños en sus quehaceres cotidianos. Este paso suscitó otra de las intenciones investigativas del proyecto, la transcripción y análisis de los discursos, desde metodologías lingüísticas preestablecidas para este hecho. Los resultados dan cuenta de la importancia que tiene al interior de esta comunidad los diálogos e interacciones intergeneracionales que desde los significados de la infancia contribuyen a la formación y la consolidación del wayuu.
Introducción: la fibrilación auricular es la arritmia cardíaca más frecuente a nivel mundial, considerándose un problema importante de salud pública dada su elevada morbimortalidad y alta carga ...económica asociada al ataque cerebrovascular como su principal complicación tromboembólica.Objetivo: hacer una revisión narrativa de los aspectos fisiopatológicos, factores de riesgo y de la terapia anticoagulante oral en pacientes con fibrilación auricular. Métodos: utilizando las palabras claves se realizó una revisión no sistemática de la literatura disponible, tanto en inglés como en español, en las bases de datos PubMed, Science Direct, Embase, EBSCO y MEDLINE. Se seleccionaron 68 publicaciones entre ellas guías de práctica clínica, metaanálisis, revisiones sistemáticas, ensayos clínicos y artículos originales que daban respuesta a nuestro objetivo con la mejor evidencia posible. Resultados: en el inicio y mantenimiento de la fibrilación auricular participan factores de riesgos modificables y no modificables, los cuales inciden en su fisiopatología generando tanto trastornos de la formación del impulso como trastornos de la conducción. En las últimas décadas los anticoagulantes orales directos han comprobado igual o mayor beneficio que la warfarina, con menores tasas de efectos adversos en pacientes con fibrilación auricular no valvular. Incluso, algunos estudios sugieren la extensión de uso en fibrilación auricular valvular. Sin embargo, la warfarina sigue siendo el fármaco de elección con mayor evidencia en esta última. Conclusión: la fibrilación auricular es una arritmia cuya incidencia va en aumento dado la mayor prevalencia de factores de riesgo en la población. La anticoagulación es un pilar en la prevención del ataque cerebrovascular. Debe instaurarse con un enfoque individualizado teniendo en cuenta los efectos adversos y beneficios de cada fármaco, el perfil del paciente, el riesgo de ataque cerebrovascular y el riesgo de hemorragia mediante el uso de escalas.
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