Doses e épocas de aplicação da adubação nitrogenada sobre a produção de milho cultivado em latossolo amarelo distrófico.

FERTBIO 2010

Editorial Letter

A primeira edição de 2016 da revista Fronteiras: Journal of Social, Technological and Environmental Science, está no ar com a notícia que a partir desse volume todos os artigos contarão com os registros no DOI (Digital Object Identifier). O Doi é uma ferramenta que associa os artigos existentes nas plataformas digitais a um endereço eletrônico. As edições de 2105 já foram incluídas e até o final deste mês as demais edições receberão o registro DOI.The first edition of the journal Fronteiras 2016: Journal of Social, Technological and Environmental Science, is proud to announce the news that this volume all articles will be recorded on the DOI (Digital Object Identifier). DOI is a tool that combines the existing articles on digital platforms to an electronic address. The 2015 issues have been included and by the end of this month the other issues will receive the DOI registration

Multiple scattering effects in quasi free scattering from halo nuclei: a test to Distorted Wave Impulse Approximation

Full Faddeev-type calculations are performed for $^{11}$Be breakup on proton target at 38.4, 100, and 200 MeV/u incident energies. The convergence of the multiple scattering expansion is investigated. The results are compared with those of other frameworks like Distorted Wave Impulse Approximation that are based on an incomplete and truncated multiple scattering expansion.Comment: 7 pages, 16 figures, to be published in Phys. Rev.

Analysis of sulphadoxine/pyrimethamine resistance-conferring mutations of Plasmodium falciparum from Mozambique reveals the absence of the dihydrofolate reductase 164L mutant

<p>Abstract</p> <p>Background</p> <p><it>Plasmodium falciparum </it>is the predominant human malaria species in Mozambique and a lead cause of mortality among children and pregnant women nationwide. Sulphadoxine/pyrimethamine (S/P) is used as first line antimalarial treatment as a partner drug in combination with artesunate.</p> <p>Methods</p> <p>A total of 92 <it>P. falciparum</it>-infected blood samples, from children with uncomplicated malaria attending the Centro de Saude de Bagamoyo in the Province of Maputo-Mozambique, were screened for S/P resistance-conferring mutations in the <it>pfdhfr </it>and <it>pfdhps </it>genes using a nested mutation-specific polymerase chain reaction and restriction digestion (PCR-RFLP). The panel of genetic polymorphisms analysed included the <it>pfdhfr </it>164L mutation, previously reported to be absent or rare in Africa.</p> <p>Results</p> <p>The frequency of the S/P resistance-associated <it>pfdhfr </it>triple mutants (51I/59R/108N) and of <it>pfdhfr/pfdhps </it>quintuple mutants (51I/59R/108N <it>+ </it>437G/540E) was 93% and 47%, respectively. However, no <it>pfdhfr </it>164L mutants were detected.</p> <p>Conclusion</p> <p>The observation that a considerably high percentage of <it>P. falciparum </it>parasites contained S/P resistance-associated mutations raises concerns about the validity of this drug as first-choice treatment in Mozambique. On the other hand, no <it>pfdhfr </it>164L mutant was disclosed, corroborating the view that that this allele is still rare in Africa.</p

Probing nucleon-nucleon interactions in breakup of the one-neutron halo nucleus 11Be on a proton target

A comparison between full few-body Faddeev/Alt-Grassberger-Sandhas (Faddeev/AGS) and continuum-discretized coupled-channels calculations is made for the resonant and nonresonant breakup of 11Be on proton target at 63.7 MeV/u incident energy. A simplified two-body model is used for 11Be which involves an inert 10Be(0+) core and a valence neutron. The sensitivity of the calculated observables to the nucleon-nucleon potential dynamical input is analyzed. We show that with the present NN and N-core dynamics the results remain a puzzle for the few-body problem of scattering from light exotic halo nuclei

Real-time quantitative PCR with SYBR Green I detection for estimating copy numbers of nine drug resistance candidate genes in Plasmodium falciparum

BACKGROUND: Evaluating copy numbers of given genes in Plasmodium falciparum parasites is of major importance for laboratory-based studies or epidemiological surveys. For instance, pfmdr1 gene amplification has been associated with resistance to quinine derivatives and several genes involved in anti-oxidant defence may play an important role in resistance to antimalarial drugs, although their potential involvement has been overlooked. METHODS: The (ΔΔ)Ct method of relative quantification using real-time quantitative PCR with SYBR Green I detection was adapted and optimized to estimate copy numbers of three genes previously indicated as putative candidates of resistance to quinolines and artemisinin derivatives: pfmdr1, pfatp6 (SERCA) and pftctp, and in six further genes involved in oxidative stress responses. RESULTS: Using carefully designed specific RT-qPCR oligonucleotides, the methods were optimized for each gene and validated by the accurate measure of previously known number of copies of the pfmdr1 gene in the laboratory reference strains P. falciparum 3D7 and Dd2. Subsequently, Standard Operating Procedures (SOPs) were developed to the remaining genes under study and successfully applied to DNA obtained from dried filter blood spots of field isolates of P. falciparum collected in São Tomé & Principe, West Africa. CONCLUSION: The SOPs reported here may be used as a high throughput tool to investigate the role of these drug resistance gene candidates in laboratory studies or large scale epidemiological surveys

Doses e épocas de aplicação da adubação nitrogenada em quatro ciclos agrícolas de grãos sob sistema plantio direto na Amazônia.

O sistema de plantio direto vem sendo praticado há 40 anos no Brasil e a maior parte da área plantada encontra-se voltada para produção de grãos. Nesse sistema, o nitrogênio é um dos nutrientes que exige maior cuidado nas ações de manejo, em virtude da multiplicidade de reações químicas e biológicas que envolvem sua dinâmica. O objetivo do trabalho foi avaliar o efeito de doses e épocas de aplicação da adubação nitrogenada sobre a produção de milho e soja, durante quatro anos de cultivo. O experimento foi conduzido em área da Embrapa Amazônia Oriental (PA), em um Latossolo Amarelo distrófico. O delineamento experimental foi em blocos casualizados, em parcelas subdivididas. Os tratamentos foram três formas de aplicação e cinco níveis de N (0, 30, 90, 90, 120 kg ha-1). Utilizou-se a sucessão milho/milho/soja/milho por quatro ciclos agrícolas. No primeiro ano de implantação do sistema plantio direto a aplicação de dose crescente de N aumentou a produção de grãos e espigas de milho. No segundo ano de cultivo a produção de grãos de milho e a altura de plantas não sofreram influência da aplicação de dose de N, devido à maior imobilização do nutriente no solo. A produção de grãos de milho e a altura de plantas, no quarto ano agrícola, apresentam comportamento linear crescente, em função de aplicação de doses de N