Cryopreservation of Byrsonima intermedia embryos followed by room temperature thawing

Byrsonima intermedia is a shrub from the Brazilian Cerrado with medicinal properties. The storage of biological material at ultra-low temperatures (-196°C) is termed cryopreservation and represents a promising technique for preserving plant diversity. Thawing is a crucial step that follows cryopreservation. The aim of this work was to cryopreserve B. intermedia zygotic embryos and subsequently thaw them at room temperature in a solution rich in sucrose. The embryos were decontaminated and desiccated in a laminar airflow hood for 0-4 hours prior to plunging into liquid nitrogen. The embryo moisture content (% MC) during dehydration was assessed. Cryopreserved embryos were thawed in a solution rich in sucrose at room temperature, inoculated in a germination medium and maintained in a growth chamber. After 30 days, the embryo germination was evaluated. No significant differences were observed between the different embryo dehydration times, where they were dehydrated for at least one hour. Embryos with a MC between 34.3 and 20.3% were germinated after cryopreservation. In the absence of dehydration, all embryos died following cryopreservation. We conclude that B. intermedia zygotic embryos can be successfully cryopreserved and thawed at room temperature after at least one hour of dehydration in a laminar airflow bench

In vitro culture of Annona emarginata: a rootstock for commercial annonaceae species

Annona emarginata is a native fruit tree in the Brazilian Cerrado which, unlike the commercial species, does not present a high fruit quality. On the other hand, it stands out based on its rootstock value. However, there are some problems that hinder the largescale production of Annona emarginata seedlings for use as a rootstock. In order to overcome these difficulties, micropropagation has become a viable alternative for the rapid and efficient propagation of Annona spp, but Annona emarginata micropropagation has not yet been reported. Therefore, the aim of this study was to initiate Annona emarginata in vitro growth. For axillary shoot proliferation, in vitro nodal segments of 0.5 cm were transferred to MS or WPM supplemented with BA at different concentrations. Nodal segments were also cultured on WPM medium with ranging concentrations of different plant growth regulators, aiming for either shoot elongation or rooting. The results showed that the use of 1 µM BA in WPM medium is recommended for in vitro multiplication of Annona emarginata. This is based on the low adventitious shoot formation, combined with a higher number of buds and leaves. The use of GA3 at any concentration tested induced the formation of malformed plants. Root formation could not be stimulated, regardless the duration of auxin treatment

Análise numérica em uma ligação de treliça de madeira com chapa metálica dentada (CMD)

A utilização da madeira como elemento estrutural dá-se, em sua grande maioria, na execução de treliças de madeira composta pela junção de diferentes barras de madeira, onde é necessária a utilização de elementos de ligação. Dentre os elementos de ligação utilizados, o presente trabalho visa estudar as ligações em chapas metálicas dentadas (CMD), que consistem em duas chapas metálicas perfuradas com dentes estampados que são aplicados nos dois lados da ligação, formando assim uma ligação plana, ou seja, sem a necessidade da sobreposição das barras. O dimensionamento dessas ligações necessita, primeiramente, de uma modelagem para a transposição dos esforços para o centro de gravidade de cada área de corte, seguida da transposição para as linhas corte. O presente trabalho tem como objetivo o estudo e comparação de modelos analíticos de dimensionamento das linhas de corte através de modelagens da ligação no software computacional Midas®.info:eu-repo/semantics/publishedVersio

Valor nutricional do mel e pólen de abelhas sem ferrão da região Amazônica

Avaliou-se os constituintes nutricionais de amostras do mel e pólen das espécies Melipona seminigra merrillae (jandaíra), Melipona compressipes manaosensis (jupará), Melipona rufiventris paraensis (uruçu boca de ralo), provenientes do meliponário da Fazenda Poranga no município de Itacoatiara - AM e Meliponário Abelhudo em Manaus - AM. Os resultados demonstraram o potencial do mel como fonte de energia, particularmente a M. rufiventris com 305,3±2,4 kcal em 100g. O pólen da espécie M. compressipes apresentou a maior concentração de proteína 15,7±0,0% e energia 309,8±0,8 kcal. Tais constatações sugerem a implementação de novos estudos visando à incorporação destes produtos na dieta dos amazônidas, possibilitando uma nova fonte alternativa de alimento potencialmente nutritivo e saudável.<br>We evaluated the nutricional constituent of honey and pollen samples of the Melipona species seminigra merrillae (jandaíra) Melipona compressipes manaosensis (jupará), Melipona rufiventris paraensis (uruçu boca de ralo), proceeding from the Poranga Honey Farm in Itacoatiara - AM, and Meliponário Abelhudo in Manaus, AM. The results demonstrated the potencial of honey as a source of energy, particularly the kcal M. rufiventris with 305.3±2.4 kcal in 100g. The compressis pollen of species presented the highest concentration of protein 15.7±0.0 % and energy 309.8±0.8 kcal. Thus we suggest the implementation of new studies aiming at the incorporation of these products in the diet of the Amazon population, making possible a new potentially nutritional and alternative healthful food source