Stereoscopic-PIV study of a dipole in a shallow fluid layer

No abstract

Luminescence and charge transfer. II. Aminomethyl anthracene derivatives as fluorescent PET (Photoinduced Electron Transfer) sensors for Protons

The importance of the modular structure ‘fluor-spacer-amine ’is pointed out for the design of fluorescent molecular sensors for pH according to the principle of photoinduced electron transfer (PET). Anthracen-9-yl methylamines (24) and some azacrown ether analogues (15 and 23) are examined in this context. They show pH-dependent fluorescence quantum yields describable by eqn. (5) while all other electronic spectral parameters remain essentially pH-invariant. The range of pKa values of these sensors are understandable in terms of macrocyclic effects and the transmission of electric fields across the anthracene short axis. Phase-shift fluorometric determination of the fluorescence lifetimes of these sensors allows the calculation of the rate constant of PET in their proton-free form to be 1010–1011 s–1, with the diamines 23 and 24b exhibiting the faster rates

Water-soluble glutamic acid derivatives produced in culture by Penicillium solitum IS1-A from King George Island, Maritime Antarctica

A new method of screening was developed to generate 770 organic and water-soluble fractions from extracts of nine species of marine sponges, from the growth media of 18 species of marine-derived fungi, and from the growth media of 13 species of endophytic fungi. The screening results indicated that water-soluble fractions displayed significant bioactivity in cytotoxic, antibiotic, anti-Leishmania, anti-Trypanosoma cruzi, and inhibition of proteasome assays. Purification of water-soluble fractions from the growth medium of Penicillium solitum IS1-A provided the new glutamic acid derivatives solitumine A (1), solitumine B (2), and solitumidines A-D (3-6). The structures of compounds 1-6 have been established by analysis of spectroscopic data, chemical derivatizations, and vibrational circular dichroism calculations. Although no biological activity could be observed for compounds 1-6, the new structures reported for 1-6 indicate that the investigation of water-soluble natural products represents a relevant strategy in finding new secondary metabolites8315565COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informação2013/50228-8; 2014/ 25222-9; 2016/21341-9; 2017/06014-4; 2013/23153-7; 2016/16033-

Produção de mudas por estaquia de duas espécies de guaco Nursery plants production of two "guaco" species

Visando a obtenção de subsídios técnicos à produção em escala comercial, avaliou-se o substrato e o sistema de irrigação mais indicados para a estaquia do guaco. Também foi observado o desenvolvimento a campo das duas espécies, Mikania glomerata e Mikania laevigata. No experimento de estaquia, foram avaliados os substratos (casca de arroz carbonizada, areia e solo), e os sistemas de irrigação (nebulização ou rega manual), no delineamento experimental de blocos casualizados, com quatro repetições e vinte estacas por parcela. As estacas utilizadas tinham 12 cm de comprimento, 0,7 a 1,0 cm de diâmetro e foram retiradas da parte mediana dos ramos. A avaliação foi feita 60 dias após a instalação do experimento. Constatou-se que o enraizamento foi melhor no substrato casca de arroz carbonizada, sendo obtidas 94,38% de estacas enraizadas para M. laevigata e 88,12% para M. glomerata. O sistema de irrigação não influenciou a porcentagem de enraizamento, mas foi observado maior volume e massa seca de raízes sob rega manual. Na observação sobre o desenvolvimento a campo das duas espécies, constatou-se que M. laevigata apresentou maior tolerância ao frio que M. glomerata. O rendimento de M. laevigata, avaliado 17 meses após o plantio, resultou em 501,5 g de matéria seca de folhas/planta. Com base nestes experimentos, concluiu-se que a estaquia do guaco pode ser realizada em casca de arroz carbonizada, sob rega manual.<br>Technical subsidies for the commercial production scale of "guaco", were evaluated, determining the better substratum and irrigation systems for rooting cuttings of "guaco". The development of the two species (Mikania glomerata and Mikania laevigata) was observed in the field. Different substrata in the cuttings experiment were evaluted (carbonized rice husk, sand and soil), under two irrigation systems (intermittent mist or manual irrigation). The experimental design was a randomized complete block, with four replications and twenty cuttings per plot. Cuttings were 12 cm long and 0.7-10 cm in diameter, taken from the medium part of the branches. Data were obtained 60 days after the installation of the experiments. The best rooting occurred in carbonized rice husk, with 94,38% of rooting cuttings for M. laevigata and 88,12% for M. glomerata. The irrigation systems did not affect the rooting, but the greatest volume and dry matter of roots were observed with manual irrigation. In the comparison of yield between the two species, M. laevigata presented larger tolerance to frost than M. glomerata. Mean yield of M. laevigata, evaluated 17 months after planting date, resulted in 501,5 g of dry matter/plant. We concluded that the propagation through cuttings can be done with carbonized rice husk, under manual irrigation