Dynamics of physiological and biochemical changes\ud during somatic embryogenesis of Acca sellowiana

Feijoa (Acca sellowiana [O. Berg] Burret [Myrtaceae]) is a native fruit species of southern Brazil and northern Uruguay. This species is amenable to somatic embryogenesis and therefore suitable as a model system for comparative studies of zygotic and somatic embryo development. In seed plants, embryogenesis involves three main steps, which are regulated by many factors, such as hormones, proteins, polyamines, and transcription factors. In the present work, the dynamics of protein, sugar, starch, amino acid, and polyamine accumulation were assayed during somatic embryogenesis of A. sellowiana. Protein, starch, amino acid, and polyamine levels accumulated unevenly during the induction phase of somatic embryogenesis, while the sugar content remained stable. Throughout the different developmental stages of somatic embryogenesis, synthesis and accumulation of proteins and amino acids showed patterns similar to those reported previously during the development of zygotic embryos of this same species. Differential patterns of polyamine accumulation were observed. This is important because these compounds affect the synthesis of other endogenous growth regulators, such as auxinindole-3-acetic acid that is mainly involved in the establishment of embryo polarity. Taken together, the present work brings new insights to the physiological and biochemical dynamics that occur during somatic embryogenesis of A. sellowiana

Avanços na qualidade de vida em portadores de narcolepsia

Narcolepsy is a chronic neurologic disease characterized by excessive daytime sleepiness and cataplexy, with daily activities impairment. The present report describes the main update data of narcolepsy etiology and Quality of Life. The recent advances show that narcolepsy is due to low orexin secretion by lateral hypothalamic neurons. Narcolepsy is accompanied by decrease in Quality of Life, with the impaiment of phsical and emotional funcions, reducing social life. The impact of narcolepsy include the burden of social, domestic, work and educational déficits. Narcolepsy is also accompanied by high levels of traffic, work environment, and home accidents. The excessive daytime sleepiness is the main factor that impairs Quality of Life in narcoleptics.cataplejía, comprometiendo las actividades diarias. La presente publicación realiza una actualización de los principales avances enfocando principalmente la etiología y el comprometimiento de la calidad de vida. Los avances en la etiología evidencian que la narcolepsia se debe al déficit de secreción del orexina, un neurotransmisor estimulante descrito recientemente por las neuronas situadas en el hipotálamo lateral. La narcolepsia lleva al comprometimiento de la calidad de vida, con comprometimiento de funciones físicas y emocionales, reduciendo la vida social. El impacto de la narcolepsia lleva al déficit en las actividades domésticas, sociales, del trabajo y la vida escolar. Es caracterizada por tasas elevadas de accidentes, tanto automovilísticos, como en el trabajo y en el hogar. La somnolencia diurna excesiva es el síntoma de la narcolepsia que más perjudica la calidad de vida.La narcolepsie est une maladie neurologique chronique qui se caractérise par une somnolence diurne excessive et par des crises de cataplexie, en compromettant les activités quotidiennes.  Cette publication actualise les avancées principales, focalisant principalement l’étiologie et ce qui compromet la Qualité de Vie. Les avancées en étiologie mettent en évidence que la narcolepsie est due à un déficit dans la sécrétion d’orexine - un neurotransmetteur stimulant décrit récemment – par les neurones situés dans l’hypothalamus latéral. La narcolepsie compromet la Qualité de Vie, avec compromission de fonctions physiques et émotionnelles, en réduisant la vie sociale. L'impact de la narcolepsie mène à un déficit dans les activités domestiques, sociales, du travail et scolaire. Elle s'accompagne de taux élevés d'accidents, tant d'automobiles, comme au travail et au foyer. La somnolence diurne excessive est le symptôme de la narcolepsie qui le plus nuit à la Qualité de Vie.A narcolepsia é uma doença neurológica crônica que se caracteriza por levar à sonolência diurna excessiva e por crises de cataplexia, comprometendo as atividades diárias. A presente publicação realiza uma atualização dos principais avanços focalizando principalmente a etiologia e o comprometimento da Qualidade de Vida. Os avanços na etiologia evidenciam que a narcolepsia se deve a déficit de secreção de orexina – um neurotransmissor estimulante descrito recentemente – pelos neurônios situados no hipotálamo lateral. A narcolepsia leva ao comprometimento da Qualidade de Vida, com comprometimento de funções físicas e emocionais, reduzindo a vida social. O impacto da narcolepsia leva ao déficit nas atividades domésticas, sociais, do trabalho e escolares. Acompanha-se de taxas elevadas de acidentes, tanto automotivos, como no trabalho e no lar. A sonolência diurna excessiva é o sintoma da narcolepsia que mais prejudica a Qualidade de Vida

Monte Carlo simulation applied in total reflection X-ray fluorescence: Preliminary results

The X-ray Fluorescence (XRF) analysis is a technique for the qualitative and quantitative determination of chemical constituents in a sample. This method is based on detection of the characteristic radiation intensities emitted by the elements of the sample, when properly excited. A variant of this technique is the Total Reflection X-ray Fluorescence (TXRF) that utilizes electromagnetic radiation as excitation source. In total reflection of X-ray, the angle of refraction of the incident beam tends to zero and the refracted beam is tangent to the sample support interface. Thus, there is a minimum angle of incidence at which no refracted beam exists and all incident radiation undergoes total reflection. In this study, we evaluated the influence of the energy variation of the beam of incident x-rays, using the MCNPX code (Monte Carlo NParticle) based on Monte Carlo method. © 2013 AIP Publishing LLC