Determination of the Dependence of Thermal Diffusivity with Moringa Concentration by Thermal Lens as a Sensitive Experimental Technique.

The use of photothermal techniques has become of special importance due to their versatile application in the thermal characterization of materials. Therefore, the thermal lens technique in the mismatched dual-beam mode is an alternative, sensitive and non-evasive tool that was used in this research to determine the thermal diffusivity of Moringa oleifera. The dual arrangement of the thermal lens technique is based on the use of an Ar+Xe excitation laser (422 nm) and a He-Ne laser (632 nm) test laser. Moringa solutions were prepared by green synthesis with different concentrations ranging from 1.56 mg·mL-1, 3.12 mg·mL-1, 6.25 mg·mL-1 to 12.50 mg·mL-1. Different optical techniques (UV-vis, FTIR, XPS and EDS) were used to characterize the Moringa leaf powders. Results showed that the increase of thermal diffusivity could be related to the presence of functional groups and metallic elements in Moringa elemental composition. In this work, it was found that the thermal diffusivity of Moringa increases with increasing concentration. This study will be useful for application in heat transport and drug release.

Thermal diffusivity of nanofluids containing Au/Pd bimetallic nanoparticles of different compositions.

Colloidal suspensions of bimetallic Au/Pd nanoparticles were prepared by simultaneous reduction of the metal ions from their corresponding chloride salts with polymer (PVP) stabilizer. Thermal properties of water containing bimetallic nanoparticles with different nominal compositions (Au/Pd = 12/1, 5/1, 1/1, 1/5) were measured using the mode mismatched dual-beam thermal lens technique to determine the effect of particle composition on the thermal diffusivity of the nanofluids. The characteristic time constant of the transient thermal lens was estimated by fitting the experimental data to the theoretical expression for transient thermal lens. The thermal diffusivity of the nanofluids (water, containing Au/Pd bimetallic nanoparticles) is seen to be strongly dependent on the composition of the particles. The maximum diffusivity was achieved for the nanoparticles with highest Au/Pd molar ratio. A possible mechanism for such high thermal diffusivity of the nanofluids with bimetallic particles is given. UV-Vis spectroscopy, TEM and high-resolution electron microscopy (HREM) techniques were used to characterize the Au/Pd bimetallic nanoparticles.

[Anti-hypertensive effect of eprosartan in diabetic patients]. / Efecto antihipertensivo del eprosartan en pacientes diabéticos.

OBJECTIVE: Diabetes mellitus seems to induce an special difficulty to control the high blood pressure. This effect is more severe on the SBP. Previous reports suggest that a new angiotensin receptor blocker, eprosartan, might have a higher efficacy to reduce SBP. It has been evaluated the BP decrease obtained with eprosartan in a group of diabetics patients compared to non diabetic patients. MATERIAL AND METHODS: 81 patients were recruited of whom 65 have ended follow-up. 34 patients were diabetics (mean age 66.7+/-10.7 years, 15 men and 19 women) and 31 were non diabetics control patients (mean age 61.8+/-12,8 years, 13 men and 18 women). All patients were treated with (600 mg) once daily. The doses was ingested in the morning. They were made three follow up visits (1, 3 and 6 mo after the first visit). RESULTS: SBP was significantly decreased both in diabetics (baseline 170.9+/-12.0, final 139.1+/-13.0 mmHg, p < 0.001) and in non diabetics group (baseline 169.9+/-18.0, final 142.0+/-13.3 mmHg, p < 0.001). DBP was also reduced in both groups (diabetics: baseline 92.9+/-9.7, final 78.4+/-8.5 mmHg, p < 0.001; non diabetics: baseline 95.6+/-7.9, final 79.1+/-7.4 mmHg, p < 0.001). Differences between the groups were not significant in any visit. Final BP reduction reached was -31.7/-14.6 mmHg in diabetics vs -27,6/-16,5 mmHg in non diabetics patients (difference is not significant) Pulse pressure changes were not different between the two groups (diabetics, 17.8+/-14.5, vs non diabetics, 11.1+/-13.2 mmHg). Two diabetic patients need a second drug to achieve BP goal and no one in non diabetic group. No adverse effects were reported. CONCLUSIONS: Eprosartan seems to be an effective drug to reduce SBP, DBP and pulse pressure with the same effectiveness in diabetics and non diabetic patients.

Efecto antihipertensivo del eprosartan en pacientes diabéticos / Anti-hipertensive effect of eprosartan in diabetic patients

Objetivo: La presencia de diabetes mellitus parece conferir una dificultad especial en el control de la HTA incidiendo particularmente sobre el componente sistólico de la PA. Estudios previos sugieren que un nuevo antagonista de los receptores de angiotensina, eprosartan, podría tener una mayor eficacia en la reducción de la PAS. Se ha evaluado de forma comparativa la reducción de la PA obtenida con eprosartan en un grupo de pacientes diabéticos y sin diabetes mellitus. Material y métodos: Se reclutaron para el estudio 81 pacientes de los cuales 65 habian terminado el periodo de seguimiento. De ellos, 34 pacientes eran diabéticos (edad 66,7 ± 10,7, 15 hombres y 19 mujeres) y 31 no padecían diabetes (edad 61,8 ± 12,8, 13 varones y 18 mujeres). Todos los pacientes fueron tratados con eprosartan (600 mg) en dosis única matutina. Se realizaron visitas de revisión al mes, a los 3 meses y a los 6 meses de la primera consulta. Resultados: La PAS se redujo significativamente tanto en el grupo de diabéticos ( inicial 170,9 ± 12,0, final 139,1 ± 13,0 mmHg, p < 0,001) como en el grupo sin diabetes (inicial 169,9 ± 18,0, final 142,0 ± 13,3 mmHg, p < 0,001). Lo mismo ocurrió con la PAD tanto en diabéticos (inicial 92,9 ± 9,7, final 78,4 ± 8,5 mmHg, p < 0,001) como en pacientes sin diabetes (inicial 95,6 ± 7,9, final 79,1 ± 7,4 mmHg, p < 0,001). Las diferencias entre ambos grupos no fueron significativas ni en la visita inicial ni en ninguna de las visitas de revisión. La reducción final obtenida fue -31,7 / -14,6 mmHg en diabéticos y -27,6 / -16,5 mmHg en paciente sin diabetes (diferencia sin significación). La reducción final en la presión de pulso no fue diferente entre ambos grupos (diabéticos, 17,8 ± 14,5, frente a pacientes sin diabetes, 11,1 ± 13,2 mmHg). Dos pacientes diabéticos necesitaron añadir otro fármaco al tratamiento para conseguir el control de la PA y ninguno en el grupo de pacientes sin diabetes. No se han detectado efectos secundarios. Conclusiones: El eprosartan demostró ser un fármaco efectivo para reducir ambos componentes de la PA, sin perder eficacia en los pacientes que padecen diabetes mellitus (AU)