30 research outputs found
Evaluación de la extracción del colorante de totumo (Crescentia cujete L.) en un producto textil
The objective of this study was to evaluate the extraction of colorant from the pulp of the fruit of calabash tree (Crescentia cujete L.) obtained in Granada (Meta, Colombia). Such extraction was performed using three different solvents (water, sodium hydroxide, and ethanol) to determine (1) the solvent that offers the highest yield and the greatest stability in resistance tests applied to a textile product and (2) the metabolites present in the samples. For this purpose, the dye was extracted by the digestion method, where 150 g of pulp were placed in three different beakers, adding water, ethanol, and sodium hydroxide until a volume of 300 ml was reached over 20 minutes, 30 minutes, and 1 hour, respectively, at a constant agitation and a temperature of 75 °C. The residues were filtered and weighed. The samples thus obtained were used to dye 2x2-cm pieces of cotton, which were subjected to resistance tests with acids and alkalis, high temperatures, and detergent. The final color was determined by a colorimeter to obtain its coordinates in the CIEL*a*b* color space. Finally, by means of spectrophotometry and peaks in the absorbance spectrum plots, it was possible to study the presence of organic pigments in the samples. The NaOH solvent achieved the best performance in the resistance tests. In turn, the sample dyed with the colorant extracted using ethanol showed a total color difference of ΔE = 3.41, which was the lowest color loss in this study. The sample treated with NaOH exhibited peaks at 270–370 nm, indicating the presence of flavonoids; and that treated with ethanol, peaks at 665–700 nm, signaling the presence of saponins. According to the above, it is possible to extract a colorant from the calabash tree fruit, which makes it a potential agro-industrial raw material.La presente investigación tuvo como objetivo evaluar la extracción del colorante de la pulpa del fruto de totumo (Crescentia cujete L.) obtenido en el municipio de Granada, departamento del Meta. Para ello se usaron tres distintos solventes: agua, hidróxido de sodio y etanol, lo cual permitió determinar el colorante de mayor rendimiento, el más estable ante pruebas de resistencia aplicado en un producto textil y la determinación de metabolitos. Esto se logró mediante la extracción del colorante por el método de digestión, en donde se agregó 150 g de pulpa a tres vasos diferentes de precipitado, adicionando agua, etanol e hidróxido de sodio hasta alcanzar un volumen de 300 ml durante un tiempo de 20 minutos, 30 minutos y 1 hora, respectivamente, a una agitación y temperatura constante de 75 °C. Se filtraron y pesaron los residuos y, una vez obtenidas las muestras, estas se utilizaron para teñir fragmentos de algodón de 2 x 2 cm, los cuales se sometieron a pruebas de resistencia con ácidos y álcalis, altas temperaturas y detergente. El color final se determinó empleando el colorímetro para obtener las coordenadas del círculo cromático de la escala CIEL a* b*. Finalmente, mediante espectrofotometría, se logró, por medio de los rangos de longitud de onda, considerar la existencia de pigmentos orgánicos presentes en dichas muestras. Se evidenció que el NaOH fue el solvente de mayor rendimiento. La muestra teñida con colorante extraído con etanol dio una diferencia total de color ΔE = 3,41, considerándolo el de menor pérdida de color. Para la muestra con NaOH se obtuvo un rango de 270-370 nm, lo que indica presencia de flavonoides y, para el extracto con etanol se obtuvo un rango de 665-700 nm, lo cual indica presencia de saponinas. De acuerdo con lo anterior, es posible efectuar la extracción de color a partir del totumo, lo cual convierte este producto en una materia prima con potencial agroindustrial
Integrated quantitative PIXE analysis and EDX spectroscopy using a laser-driven particle source
Among the existing elemental characterization techniques, Particle Induced
X-ray Emission (PIXE) and Energy Dispersive X-ray (EDX) spectroscopy are two of
the most widely used in different scientific and technological fields. Here we
present the first quantitative laser-driven PIXE and laser-driven EDX
experimental investigation performed at the Centro de L\'aseres Pulsados in
Salamanca. Thanks to their potential for compactness and portability,
laser-driven particle sources are very appealing for materials science
applications, especially for materials analysis techniques. We demonstrate the
possibility to exploit the X-ray signal produced by the co-irradiation with
both electrons and protons to identify the elements in the sample. We show
that, using the proton beam only, we can successfully obtain quantitative
information about the sample structure through laser-driven PIXE analysis.
These results pave the way towards the development of a compact and
multi-functional apparatus for the elemental analysis of materials based on a
laser-driven particle source.Comment: This project has received funding from the European Research Council
(ERC) under the European Union's Horizon 2020 research and innovation
programme (ENSURE grant agreement No. 647554). Submitted to Science Advances
on 20th May 2
Proton stopping measurements at low velocity in warm dense carbon
: Ion stopping in warm dense matter is a process of fundamental importance for the understanding of the properties of dense plasmas, the realization and the interpretation of experiments involving ion-beam-heated warm dense matter samples, and for inertial confinement fusion research. The theoretical description of the ion stopping power in warm dense matter is difficult notably due to electron coupling and degeneracy, and measurements are still largely missing. In particular, the low-velocity stopping range, that features the largest modelling uncertainties, remains virtually unexplored. Here, we report proton energy-loss measurements in warm dense plasma at unprecedented low projectile velocities. Our energy-loss data, combined with a precise target characterization based on plasma-emission measurements using two independent spectroscopy diagnostics, demonstrate a significant deviation of the stopping power from classical models in this regime. In particular, we show that our results are in closest agreement with recent first-principles simulations based on time-dependent density functional theory
Functional KV10.1 Channels Localize to the Inner Nuclear Membrane
Ectopically expressed human KV10.1 channels are relevant players in tumor biology. However, their function as ion channels at the plasma membrane does not totally explain their crucial role in tumors. Both in native and heterologous systems, it has been observed that a majority of KV10.1 channels remain at intracellular locations. In this study we investigated the localization and possible roles of perinuclear KV10.1. We show that KV10.1 is expressed at the inner nuclear membrane in both human and rat models; it co-purifies with established inner nuclear membrane markers, shows resistance to detergent extraction and restricted mobility, all of them typical features of proteins at the inner nuclear membrane. KV10.1 channels at the inner nuclear membrane are not all transported directly from the ER but rather have been exposed to the extracellular milieu. Patch clamp experiments on nuclei devoid of external nuclear membrane reveal the existence of channel activity compatible with KV10.1. We hypothesize that KV10.1 channels at the nuclear envelope might participate in the homeostasis of nuclear K+, or indirectly interact with heterochromatin, both factors known to affect gene expression
Serum levels of interleukin-6, tumor necrosis factor-alpha and interferon-gama in infants with and without dengue
CARACTERIZACIÓN DEL ESTRÉS OXIDATIVO EN RATAS WISTAR DIABÉTICAS POR ESTREPTOZOTOCINA OXIDATIVE STRESS CARACTERIZATION IN STREPTOZOTOCIN-DIABETIC WISTAR RATS
La diabetes es un trastorno metabólico crónico de gran alcance epidemiológico. Numerosos estudios han demostrado que la diabetes mellitus se encuentra asociada al incremento de la formación de radicales libres derivados del oxígeno y a la disminución del potencial antioxidante del organismo, generando el daño oxidativo de algunos componentes de la célula tales como las proteínas, carbohidratos, lípidos y ácidos nucleicos. Este trabajo pretende establecer, en ratas Wistar, la relación dosis-respuesta de estreptozotocina frente a los niveles de glucosa y a diferentes parámetros del estatus antioxidante. Como marcadores del daño asociado a las especies de oxígeno reactivas se evaluó la actividad enzimática de catalasa y de superóxido dismutasa, la capacidad antioxidante total del plasma y la peroxidación lipídica. Los resultados obtenidos evidencian una clara relación de la dosis de estreptozotocina con los niveles de glucosa y los parámetros de estrés oxidativo evaluados luego de 20 días de la inducción de la diabetes experimental.Diabetes is a chronic metabolic disease. Numerous studies have demonstrated that diabetes mellitus is associated to free radicals increase derived from oxygen and to the organism potential antioxidant decrease generating oxidative damage of some cell components like proteins, nucleic acids, carbohydrates and lipids. After 20 days of administration of streptozotocin in Wistar rats, we have found a relationship between levels of blood glucose and some markers from antioxidant status. We evaluate oxidative stress markers like catalasa and superoxide dismutase acivities, ferric reducing ability of plasma and thiobarbituric acid reactive species
EFECTO DE NAPROXENO MICROENCAPSULADO EN MICROESFERAS DE ÁCIDO POLI (LÁCTICO-CO-GLICÓLICO) SOBRE EDEMA PLANTAR INDUCIDO POR CARRAGENINA EN RATAS EFFECT OF MICROENCAPSULATED NAPROXEN INTO POLY(LACTIDE-CO-GLYCOLIDE) MICROSPHERES ON CARRAGEENIN PAW EDEMA IN RATS
Las micropartículas son sistemas de entrega de fármacos ampliamente utilizados, que permiten mejorar la aplicabilidad terapéutica de fármacos tanto nuevos como convencionales. En el presente trabajo se elaboran micropartículas de un polímero biodegradable, ácido poli (láctico-co-glicólico), cargadas con naproxeno. Las mejores condiciones para la elaboración de las micropartículas son determinadas experimentalmente, encontrando que la relación fármaco: polímero, la cantidad de isopropanol, el volumen de fase acuosa, la velocidad de agitación y el tiempo de agitación influyen significativamente en las características de las micropartículas obtenidas. En el modelo de edema plantar inducido por carragenina en ratas Wistar, se encuentra que el naproxeno microencapsulado en dosis de 5 mg/Kg y 10 mg/Kg presenta mayor efecto antiinflamatorio que el naproxeno libre en dosis de 10 mg/Kg.ABSTRACT Microparticles are pharmaceutical dosage forms widely used because they may improve the therapeutic application of new and conventional drugs. In this work we make biodegradable microparticles with poly (lactic-co-glicolic) acid as polymer loaded with naproxen. The best microencapsulation conditions are experimentally determinate. We have found that the drug:polymer ratio, the isopropanol amount, the aqueous phase volume, the stir speed and the time of stir affect the microparticles characteristics. In the carragenin paw edema model, we have found that the microencapsulated naproxen at 5 mg/Kg and 10 mg/Kg showed greater effect than free naproxen at 10 mg/Kg
Integrated quantitative PIXE analysis and EDX spectroscopy using a laser-driven particle source
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A quasi-monoenergetic short time duration compact proton source for probing high energy density states of matter
We report on the development of a highly directional, narrow energy band, short time duration proton beam operating at high repetition rate. The protons are generated with an ultrashort-pulse laser interacting with a solid target and converted to a pencil-like narrow-band beam using a compact magnet-based energy selector. We experimentally demonstrate the production of a proton beam with an energy of 500 keV and energy spread well below 10[Formula: see text], and a pulse duration of 260 ps. The energy loss of this beam is measured in a 2 [Formula: see text]m thick solid Mylar target and found to be in good agreement with the theoretical predictions. The short time duration of the proton pulse makes it particularly well suited for applications involving the probing of highly transient plasma states produced in laser-matter interaction experiments. This proton source is particularly relevant for measurements of the proton stopping power in high energy density plasmas and warm dense matter