Effects of carbon source, carbon concentration and culture conditions on in vitro rooting of Pinus pinea L. microshoots

In stone pine (Pinus pinea L.), clonal propagation via adventitious shoot formation from cotyledons has been reported before but rooting of these shoots is poor. The number of rooted shoots had low frequency limiting the used of micropropagation protocols as a choice for mass propagation of superior genotypes. Therefore the main objective of the present work was to increase the number and quality of roots per shoot in order to ensure the survival and growth of a great number of plants in the acclimation phase. To achieve this, different combinations of carbon source (sucrose or glucose) at different concentrations, under different environmental conditions (temperature and light), were tested in the induction and expression phases of the adventitious root formation. Shoots of different clones obtained via organogenesis have been employed for the experiments. Observations were made on the rooting percentage, root length and number of roots per shoot. The results showed a general increased of the number of roots per shoot and an earlier root formation when glucose was used as a carbon source. However, there were no differences in the percentage of rooting between the carbons sources tested. The best results were obtained using 0.117 M of glucose and dark treatment combined with 19°C during the induction phase of the rhizogenic process. Light and low sugar concentration proved to be beneficial for the expression phase, increasing the root length. A remarkable interclonal difference in the ability to form roots was observed. It was possible to obtain a rooting percentage of more than 75% in several of the tested clones

A serigrafia como expressão artística

O Relatório de Estágio com o título A Serigrafia como Expressão Artística, enquadra e descreve brevemente as atividades que realizei no âmbito de um estágio curricular que decorreu no Centro Português de Serigrafia (CPS), em Lisboa, entre outubro de 2022 e janeiro de 2023. Através de uma reflexão sobre a emancipação da serigrafia como expressão artística e de um breve enquadramento da sua origem em Portugal, destaco o papel do Centro Português de Serigrafia e também de alguns novos impressores. A serigrafia é uma técnica de impressão manual, hoje industrializada, que está muito em voga, pois permite a edição tanto de pequenas como grandes tiragens e ser adquirida a preços mais acessíveis. O Centro Português de Serigrafia tem como objetivo a reprodução da obra de artistas contemporâneos, apoiando e divulgando o seu trabalho original. Durante este estágio pude colaborar no processo técnico em alguns projetos e observar o desenvolvimento de outros, e constatei que a serigrafia é cada vez mais considerada e apreciada pelas possibilidades experimentais e plásticas que oferece.This Report with the title Serigraphy as an Artistic Technique, frames and briefly describes the activities that I carried out as part of a curricular internship that took place at the Centro Português de Serigrafia (CPS), in Lisbon, between October 2022 and January 2023. Through a reflection on the emancipation of serigraphy as an artistic expression and a brief contextualization of its origins in Portugal, I highlight the role of the Centro Português de Serigrafia and of some new printers. Silkscreen is a manual printing technique, now industrialized, which is currently very fashionable, as it allows both small and large print runs to be published and acquired at more accessible prices. The Centro Português de Serigrafia aims at reproducing the work of contemporary artists, supporting, and disseminating their original work. During this internship, I was able to collaborate in some projects and observe the development of others, and I noticed that silkscreen is increasingly being worked in an experimental, free, and plastic way

Excitation mechanisms and characterization of a multi-ionic xenon laser

The emission characteristics of an ultraviolet-visible pulsed multi-ionic xenon laser were studied through time-resolved spectroscopy and the results were interpreted using a collisional-radiative theoretical model. This analysis includes more than 20 laser lines belonging to several ionic species (Xe III-VIII). Depending on the experimental conditions, different temporal distributions of the laser lines and their corresponding spontaneous emissions can be observed. In particular, laser emission presents temporal oscillations near threshold. Pumping processes for the laser transitions have been analyzed by using this model. Relativistic Hartree-Fock calculations of laser level lifetimes and radiative transition probabilities were performed. Experimental laser gain for several transitions were obtained and compared with the theoretical values derived from the calculations

Excitation Mechanisms and Characterization of a Multi-Ionic Xenon Laser

The emission characteristics of an ultraviolet-visible pulsed multi-ionic xenon laser were studied through time-resolved spectroscopy and the results were interpreted using a collisional radiative theoretical model. This analysis includes more than 20 laser lines belonging to several ionic species (Xe III VIII). Depending on the experimental conditions, different temporal distributions of the laser lines and their corresponding sponta neous emissions can be observed. In particular, laser emission presents temporal oscillations near threshold. Pumping processes for the laser transitions have been analyzed by using this model. Relativistic Hartree Fock calculations of laser level lifetimes and radiative transition probabilities were performed. Experimental laser gain for several transitions were obtained and compared with the theoretical values derived from the calculations.Facultad de Ingenierí

Excitation Mechanisms and Characterization of a Multi-Ionic Xenon Laser

The emission characteristics of an ultraviolet-visible pulsed multi-ionic xenon laser were studied through time-resolved spectroscopy and the results were interpreted using a collisional-radiative theoretical model. This analysis includes more than 20 laser lines belonging to several ionic species (Xe III-VIII). Depending on the experimental conditions, different temporal distributions of the laser lines and their corresponding spontaneous emissions can be observed. In particular, laser emission presents temporal oscillations near threshold. Pumping processes for the laser transitions have been analyzed by using this model. Relativistic Hartree-Fock calculations of laser level lifetimes and radiative transition probabilities were performed. Experimental laser gain for several transitions were obtained and compared with the theoretical values derived from the calculation

Excitation Mechanisms and Characterization of a Multi-Ionic Xenon Laser

The emission characteristics of an ultraviolet-visible pulsed multi-ionic xenon laser were studied through time-resolved spectroscopy and the results were interpreted using a collisional radiative theoretical model. This analysis includes more than 20 laser lines belonging to several ionic species (Xe III VIII). Depending on the experimental conditions, different temporal distributions of the laser lines and their corresponding sponta neous emissions can be observed. In particular, laser emission presents temporal oscillations near threshold. Pumping processes for the laser transitions have been analyzed by using this model. Relativistic Hartree Fock calculations of laser level lifetimes and radiative transition probabilities were performed. Experimental laser gain for several transitions were obtained and compared with the theoretical values derived from the calculations.Facultad de Ingenierí