287 research outputs found

    Synthesis of Shape-Tailored WO3 Micro-/Nanocrystals and the Photocatalytic Activity of WO3/TiO2 Composites

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    A traditional semiconductor (WO3) was synthesized from different precursors via hydrothermal crystallization targeting the achievement of three different crystal shapes (nanoplates, nanorods and nanostars). The obtained WO3 microcrystals were analyzed by the means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and diffuse reflectance spectroscopy (DRS). These methods contributed to the detailed analysis of the crystal morphology and structural features. The synthesized bare WO3 photocatalysts were totally inactive, while the P25/WO3 composites were efficient under UV light radiation. Furthermore, the maximum achieved activity was even higher than the bare P25's photocatalytic performance. A correlation was established between the shape of the WO3 crystallites and the observed photocatalytic activity registered during the degradation of different substrates by using P25/WO3 composites

    Laser-induced chemical transformation of freestanding graphene oxide membranes in liquid and gas ammonia environments

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    Laser-induced chemical conversion of graphene oxide (GO) is an effective way to modify its properties and expand its potential use for numerous applications. In this work, a mechanically stable and flexible free-standing GO membrane is synthesized and further processed by ultraviolet laser radiation in gas and liquid ammonia-rich environments. Electron and atomic force microscopy, as well as X-ray photoelectron spectroscopy analysis, reveal that laser irradiation in gas leads to a large defect-induced morphology modification and high deoxygenation process, accompanied by the slight incorporation of nitrogen functionality to the reduced GO structure. Conversely, irradiation in liquid provokes significant integration of nitrogen groups, essentially amines, into a partially reduced GO structure, without evident modification of the morphology. Electrical measurements on the macro- and nano-scale point to a complex contribution of morphology and oxidized regions to the overall resistance of the rGO.The authors acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness under the project ENE2014-56109-C3-3-R, in addition to the Romanian National Authority for Scientific Research and Innovation, CNCS – UEFISCDI, under the Grants PN-II-ID-PCE-2012-4-0292 and PNII- RU-TE-2014-4-1194. ICMAB acknowledges financial support from the Spanish Ministry of Economy and Competitiveness, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0496).Peer reviewe

    Patterns of the parasite communities in a fish assemblage of a river in the Brazilian Amazon region.

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    This paper characterizes the pattern of ectoparasite and endoparasite communities in an assemblage of 35 sympatric fish from different trophic levels in a tributary from the Amazon River system, northern Brazil. In detritivorous, carnivorous, omnivorous and piscivorous hosts, the species richness consisted of 82 ectoparasites and endoparasites, but protozoan ectoparasites such as Ichthyophthirius multifiliis, Piscinoodinium pillulare and Tripartiella sp. were dominant species predominated, such that they were present in 80% of the hosts. The taxon richness was in the following order: Monogenea > Nematoda > Digenea > Crustacea > Protozoa > Acanthocephala = Cestoda > Hirudinea. Among the hosts, the highest number of parasitic associations occurred in Satanoperca jurupari, Aequidens tetramerus, Hoplerythrinus unitaeniatus, Hoplosternum littorale, Cichlasoma amazonarum, Chaetobranchus flavescens, Squaliforma emarginata, Chaetobranchopsis orbicularis and Hoplias malabaricus. A weak positive correlation between ectoparasite abundance and length of the hosts was observed. Ectoparasite communities of detritivorous, carnivorous and omnivorous hosts were similar, but these differed from the communities of piscivorous hosts. Larval endoparasite species with low host specificity were the main determinants of the parasite infracommunity structure of the fish assemblage. Fish assemblage had few species of helminth that were specialist endoparasites, while many were parasites at the larval stage, infecting intermediate and paratenic hosts. Finally, carnivorous and omnivorous hosts harbored endoparasite communities that were more heterogeneous than those of detritivorous and piscivorous hosts. This result lends supports to the notion that the feeding habits of the host species are a significant factor in determining the endoparasites fauna

    Sobrevivência e crescimento inicial de espécies arbóreas em Integração Lavoura-Pecuária-Floresta no Amapá.

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    O sistema integração lavoura-pecuária-floresta (iLPF) está entre as estratégias do Plano ABC, visando aumentar a sustentabilidade das atividades agropecuárias. Esse estudo objetivou avaliar a sobrevivência e o crescimento inicial de espécies arbóreas em consórcio com espécies agrícolas em experimento conduzido no Campo Experimental do Cerrado da Embrapa Amapá, em Macapá, AP. Foram feitos seis tratamentos compostos de uma espécie arbórea nas linhas combinado com milho (Zea mays L.) ou sorgo (Sorghum bicolor) nas entrelinhas. A Gliricídia (Gliricidia sepium) e o Tachi-branco (Sclerolobium paniculatum) foram plantados em linhas simples, com um espaçamento de 2 m, com 12 m nas entrelinhas, e o Eucalipto (Eucalyptus urograndis) foi plantado em linhas duplas, com espaçamento de 2 m intercalado entre as linhas, com 10 m nas entrelinhas. Avaliou-se a sobrevivência e crescimento das arbóreas aos 30 dias, nove e 12 meses após o plantio. Observou-se a altura total, diâmetro à altura do colo (DAC) das plantas com altura igual ou inferior a 1,30 m e diâmetro à altura do peito (DAP) em plantas com altura superior a 1,30 m. As taxas de sobrevivência para as três espécies testadas foram: 88,1% para Tachi-branco, 99,8% para Gliricídia e 99,7% para Eucalipto. A altura média das árvores aos 12 meses foi 4,04 m, variando de 1,50 m a 5,74 m, sendo Tachi-branco o que apresentou o menor crescimento (1,50 m). O Eucalipto apresentou o maior desenvolvimento, com alturas médias de 3,03 m (9 meses) e 5,74 m (12 meses). Até nove meses a Gliricídia teve o maior aumento de diâmetro (2,35 cm ± 1,25 cm), sendo ultrapassada por eucalipto aos 12 meses (5,25 cm ± 1,04 cm). Apesar de ter o menor crescimento, o Tachi-branco é uma espécie nativa interessante para consórcios que não exijam rápido crescimento. O Eucalipto é uma espécie interessante devido seu rápido crescimento, pequeno diâmetro de copa e alta produtividade, no entanto o espaçamento utilizado pode restringir a agricultura rapidamente. A Gliricídia, devido sua alta capacidade de regeneração que permite poda periódica, adapta-se muito bem em consorciação com agricultura

    Diffuse large B-cell lymphoma of Waldeyer's ring has distinct clinicopathologic features: a GELA study

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    Background Diffuse large B-cell lymphomas (DLBCLs) arising in specific extranodal sites have peculiar clinicopathologic features. Patients and methods We analyzed a cohort of 187 primary Waldeyer's ring (WR) DLBCLs retrieved from GELA protocols using anthracyclin-based polychemotherapy. Results Most patients (92%) had stage I-II disease. A germinal center B-cell-like (GCB) immunophenotype was observed in 61%, and BCL2 expression in 55%, of WR DLBCLs. BCL2, BCL6, IRF4 and MYC breakpoints were observed in, respectively, 3 of 42 (7%), 9 of 36 (25%), 2 of 26 (8%) and 4 of 40 (10%) contributive cases. A variable follicular pattern was evidenced in 30 of 68 (44%) large biopsy specimens. The 5-year progression-free survival (PFS) and the overall survival (OS) of 153 WR DLBCL patients with survival information were 69.5% and 77.8%, respectively. The GCB immunophenotype correlated with a better OS (P=0.0015), while BCL2 expression predicted a worse OS (P=0.037), an effect overcome by the GCB/non-GCB classification. Compared with matched nodal DLBCLs, WR DLBCLs with no age-adjusted international prognostic index factor disclosed a better 5-year PFS rate (77.5% versus 70.7%; P=0.03). Conclusions WR DLBCLs display distinct clinicopathologic features compared with conventional DLBCLs, with usual localized-stage disease, common follicular features and a high frequency of GCB immunophenotype contrasting with a low rate of BCL2 rearrangements. In addition, they seem to be associated with a better outcome than their nodal counterpar

    Preparation, structural characterisation and antibacterial properties of Ga-doped sol-gel phosphate-based glass

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    A sol-gel preparation of Ga-doped phosphate-based glass with potential application in antimicrobial devices has been developed. Samples of composition (CaO)(0.30)(Na2O)(0.20-x) (Ga2O3) (x) (P2O5)(0.50) where x = 0 and 0.03 were prepared, and the structure and properties of the gallium-doped sample compared with those of the sample containing no gallium. Analysis of the P-31 MAS NMR data demonstrated that addition of gallium to the sol-gel reaction increases the connectivity of the phosphate network at the expense of hydroxyl groups. This premise is supported by the results of the elemental analysis, which showed that the gallium-free sample contains significantly more hydrogen and by FTIR spectroscopy, which revealed a higher concentration of -OH groups in that sample. Ga K-edge extended X-ray absorption fine structure and X-ray absorption near-edge structure data revealed that the gallium ions are coordinated by six oxygen atoms. In agreement with the X-ray absorption data, the high-energy XRD results also suggest that the Ga3+ ions are octahedrally coordinated with respect to oxygen. Antimicrobial studies demonstrated that the sample containing Ga3+ ions had significant activity against Staphylococcus aureus compared to the control

    Identificação e análise de gene efetores do gênero Neopestalotiopsis com base no genoma completo.

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    O grupo pestaloides é composto por três gêneros distintos, Pestalotiopsis, Neopestalotiopsis e Pseudopestalotiopsis, ambos com espécies fitopatogênicas e de grande importância agrícola, como por exemplo a espécie N. clavispora. Diante disso, o presente estudo tem como objetivo realizar uma análise comparativa com base no genoma completo das espécies Neopestalotiopsis sp. (M2102B), Neopestalotiopsis sp. (M2101), Neopestalotiopsis sp. (M2101E), N. clavispora (IHI 201606), Neopestalotiopsis sp. (37M) e N. rosae frente aos resultados das análises das espécies Ps. theae, P. fici e N. formicidarum de genes que codificam efetores e proteínas degradadoras de carboidratos (Cazymes).CDMICRO 2023
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