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Streptomyces remains one of the prolific sources of structural diversity, and a reservoir to mine for novel natural products. Continued screening for new Streptomyces strains in our laboratory led to the isolation of Streptomyces sp. RK44 from the underexplored areas of Kintampo waterfalls, Ghana, Africa. Preliminary screening of the metabolites from this strain resulted in the characterization of a new 2-alkyl-4-hydroxymethylfuran carboxamide (AHFA) 1 together with five known compounds, cyclo-(L-Pro-Gly) 2, cyclo-(L-Pro-L-Phe) 3, cyclo-(L-Pro-L-Val) 4, cyclo-(L-Leu-Hyp) 5, and deferoxamine E 6. AHFA 1, a methylenomycin (MMF) homolog, exhibited anti-proliferative activity (EC50 = 89.6 &micro, M) against melanoma A2058 cell lines. This activity, albeit weak is the first report amongst MMFs. Furthermore, the putative biosynthetic gene cluster (ahfa) was identified for the biosynthesis of AHFA 1. DFO-E 6 displayed potent anti-plasmodial activity (IC50 = 1.08&micro, M) against P. falciparum 3D7. High-resolution electrospray ionization mass spectrometry (HR ESIMS) and molecular network assisted the targeted-isolation process, and tentatively identified six AHFA analogues, 7&ndash, 12 and six siderophores 13&ndash, 18.

Streptomyces remains one of the prolific sources of structural diversity, and a reservoir to mine for novel natural products. Continued screening for new Streptomyces strains in our laboratory led to the isolation of Streptomyces sp. RK44 from the underexplored areas of Kintampo waterfalls, Ghana, Africa. Preliminary screening of the metabolites from this strain resulted in the characterization of a new 2-alkyl-4-hydroxymethylfuran carboxamide (AHFA) 1 together with five known compounds, cyclo-(L-Pro-Gly) 2, cyclo-(L-Pro-L-Phe) 3, cyclo-(L-Pro-L-Val) 4, cyclo-(L-Leu-Hyp) 5, and deferoxamine E 6. AHFA 1, a methylenomycin (MMF) homolog, exhibited anti-proliferative activity (EC50 = 89.6 µM) against melanoma A2058 cell lines. This activity, albeit weak is the first report amongst MMFs. Furthermore, the putative biosynthetic gene cluster (ahfa) was identified for the biosynthesis of AHFA 1. DFO-E 6 displayed potent anti-plasmodial activity (IC50 = 1.08 µM) against P. falciparum 3D7. High-resolution electrospray ionization mass spectrometry (HR ESIMS) and molecular network assisted the targeted-isolation process, and tentatively identified six AHFA analogues, 7–12 and six siderophores 13–18.

Quorum sensing is known to play a major role in the regulation of secondary metabolite production, especially, antibiotics, and morphogenesis in the phylum Actinobacteria. Although it is one of the largest bacterial phylum, only 25 of the 342 genera have been reported to use quorum sensing. Of these, only nine have accompanying experimental evidence; the rest are only known through bioinformatic analysis of gene/genome sequences. It is evident that this important communication mechanism is not extensively explored in Actinobacteria. In this review, we summarize the different quorum sensing systems while identifying the limitations of the existing screening strategies and addressing the improvements that have taken place in this field in recent years. The γ-butyrolactone system turned out to be almost exclusively limited to this phylum. In addition, methylenomycin furans, AI-2 and other putative AHL-like signaling molecules are also reported in Actinobacteria. The lack of existing screening systems in detecting minute quantities and of a wider range of signaling molecules was a major reason behind the limited information available on quorum sensing in this phylum. However, recent improvements in screening strategies hold a promising future and are likely to increase the discovery of new signaling molecules. Further, the quorum quenching ability in many Actinobacteria has a great potential in controlling the spread of plant and animal pathogens. A systematic and coordinated effort is required to screen and exploit the enormous potential that quorum sensing in the phylum Actinobacteria has to offer for human benefit.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Neste trabalho, foi desenvolvido um bloco solo-cimento com material de mudança de fase (MMF), denominado “material inteligente” por se adequar a temperaturas definidas. Inicialmente, as propriedades físicas e químicas, e a morfologia do solo argiloso do semi-árido do estado do RN, sem adição de areia e com adição de 10% de areia, foram analisadas; como também as de um outro solo argiloso da região do Alentejo, em Portugal, ao qual foi adicionado 30% de areia 04 para adequá-lo as normas da ABNT e ter as mesmas características do solo local. Para estudar o desempenho da argamassa para fabricação do bloco solo-cimento, e as suas propriedades térmicas, porcentagens de 0%, 3% e 5%, em peso, de parafina n-eicosano, com ponto de fusão de 37°C; e de parafina 120/130F, com ponto de fusão de 50.3ºC, foram adicionadas ao solo argiloso do RN. Para o solo argiloso de Portugal, foram adicionadas apenas 5%, em peso, de parafina sasolwas e n-eicosano. Após a mistura dos constituintes em massa (cimento, água, MMFs, e os solos argilosos), a argamassa foi prensada numa prensa manual sob pressão de 2MPa, a fim de estabilizar e dar forma ao bloco. Ao término da cura, foram realizados os ensaios de resistência mecânica por compressão simples, absorção de água, DSC e TG. A condutividade térmica foi medida por um equipamento modelo KD2Pro que inclui uma fonte de calor linear e uma temperatura elementar de medição com uma resolução de 0,001oC. Para os ensaios de perdas de massa em função do tempo e da temperatura, os blocos solo-cimento foram colocados no interior de uma câmara quente instrumentada com 10 termopares, sendo 4 inseridos no bloco solo-cimento de referência e no bloco solo-cimento com 5% de MMFs, ligados a um data logger modelo Agilent 34970a com aquisição de dados de 20 canais de medição de tensão AC, DC, resistência, frequência, período e temperatura direta com termopar programado para fazer uma leitura a cada 30 segundos. Os blocos solo-cimento com MMFs produzidos apresentaram resistência mecânica os valores obtido, superiores aos normativos pela ABNT, taxa de porosidade em torno de 10% e boas propriedades térmicas. Até aproximadamente 100ºC, não foram verificadas perdas de massa nos blocos com MMFs. The production of materials such as soil cement blocks from a raw material abundant, as the soil is a strong tool for the eventual solution of an emerging global problem, the increased demand for large sections of the population for better conditions villas. Meeting these needs within the current patterns of consumption can be translated by the economic application of soil cement blocks with MMFs in homes by offering good mechanical strength, thermal comfort and ease in obtaining. This work has as main objective the production of soil cement blocks with good mechanical and thermal properties. To this material was developed as follows: starting from the study of physical and chemical properties and morphology of the clayey soils of semiarid (Brazil) and Alentejo (Portugal). Initially, there is the semi-arid soil that was made without and with addition of 10% sand, 04, and then the clay soil Aletenjo which was produced without and with addition of 30% also with sand 04. For both clay soil studied, sand was added to adjust them to the recommended standards of ABNT in the manufacture of soil cement block. The performance of the mortars with addition MMFs, paraffin to manufacture soil cement blocks, percentages by weight of nparaffin, eicosane, 37 ° C melting point paraffin, and 120/ 130F, melting point 50 , 3c and paraffin sasolwax melting point 57°C, were added to the constituents of the mortar, the MMFs are called "smart" materials for adju sting the right set temperature. Then two mortars were produced, one with the clayey soils in Brazil (9 wt% cement; 9.63 wt% water, 0%, 3% and 5% w MMFs) and the other with clay soil Alentejo (9 wt% cement, 10 wt% water, 0% to 5% MMFs). After mixing the mortar was compressed with a manual press capacity 2MPa pressure in order to stabilize and to form soil cement blocks. Finishing the production process, with the cure of the material. In the final product were carried out the mechanical resistance and thermal properties (compressive, specific heat, latent heat, conductivity, strength and thermal capacity, immersion and capillary water) in addition, the material was characterized by fluorescence, SEM, DSC, TG. And the tests were performed in clayey soil: X-ray fluorescence, bulk density, true density, particle size, screening, sedimentation and Proctor test. With the trials were possible to produce soil cement blocks with good mechanical strength and thermal properties.

This paper investigates the impact of news media sentiment on financial market returns and volatility in the long-term. We hypothesize that the way the media formulate and present news to the public produces different perceptions and, thus, incurs different investor behavior. To analyze such framing effects we distinguish between optimistic and pessimistic news frames. We construct a monthly media sentiment indicator by taking the ratio of the number of newspaper articles that contain predetermined negative words to the number of newspaper articles that contain predetermined positive words in the headline and/or the lead paragraph. Our results indicate that pessimistic news media sentiment is positively related to global market volatility and negatively related to global market returns 12 to 24 months in advance. We show that our media sentiment indicator reflects very well the financial market crises and pricing bubbles over the past 20 years.