Spatial distribution of two symmetric four-wave mixing signals induced by Gaussian beams

We present a theoretical analysis of the spatial shape of two symmetric signals of degenerate four-wave mixing induced by Gaussian beams in a thin sample of two-level atoms. Our calculations take into account the full spatial and spectral dependencies of the relevant nonlinear susceptibilities that govern the two processes. This reveals two interesting effects. The first one is that the total power of incident beams affects the transverse profile of the four-wave mixing signals at the medium exit and their free propagation. The second one is the influence of the spectral characteristics of the medium on the longitudinal profile of both generated signals upon free propagation. We argue that the first effect can be seen as the saturation of the medium in regions of higher intensity, while the second can be understood as the result of a nonlinear contribution to the refractive index inside the atomic medium. These effects can be symmetric between the two signals, with asymmetries induced by different detunings from resonance of the incident fields

A pesquisa e desenvolvimento sob enfoque agroecológico na Embrapa Agropecuária Oeste: um processo em construção.

Os trabalhos de P&D na Embrapa Agropecuária Oeste voltados à Agroecologia iniciaram-se em 2005, a partir de demandas apresentadas pelas organizações dos agricultores familiares de Mato Grosso do Sul. As atividades de P&D são pautadas, predominantemente, em metodologias participativas, porém são desenvolvidos trabalhos orientados por metodologias convencionais. Nesse período, ações de pesquisa vêm sendo desenvolvidas, a partir de arranjos internos e interinstitucionais, bem como em redes locais de P&D, no âmbito de MS e interestaduais. Nesse contexto, destacam-se algumas parcerias: organizações de agricultores familiares, incluindo-se movimentos sociais, instituição de extensão rural, outras unidades da Embrapa e universidades. Alguns resultados já obtidos são a reprodução de arranjos agroecológicos pelos agricultores, conduzidos em ações participativas de P&D e indicações preliminares de espécies de adubos verdes e espécies arbóreas nativas para SAFs, ambos para diferentes ecorregiões de MS.Edição dos anais do 6º Congresso Brasileiro de Agroecologia; 2º Congresso Latinoamericano de Agroecologia, Curitiba, nov. 2009

Avaliação de substratos de húmus de minhoca na produção de mudas de alface (Lactuca sativa) cultivar Lucy Brown.

bitstream/item/68817/1/020-nascimento-avaliacao.pdfPublicado também no Cadernos de Agroecologia, v. 7, n.2, 2012

Chemical characterization and evaluation of the microbiological quality of juçaí pulp (Euterpe edulis) native to the state of Rio de Janeiro.

The juçara palm (Euterpe edulis), endemic to the Atlantic forest region, is known for producing a palm heart known for producing an excellent quality of palm heart and its extractive exploitation led to the exhaustion of the species in the natural reserves. Its fruit, juçaí, has an organoleptic, nutritional and commercial potential similar to the açaí (Euterpe oleracea), native to the Amazon region, besides representing a sustainable alternative of preservation of the species.SLACA, 12. De 4 a 7 de Novembro de 2017. Ref. 71796

Genotoxic and Cytotoxic Safety Evaluation of Papain (Carica papaya L.) Using In Vitro Assays

Papain, a phytotherapeutic agent, has been used in the treatment of eschars and as a debriding chemical agent to remove damaged or necrotic tissue of pressure ulcers and gangrene. Its benefits in these treatments are deemed effective, since more than 5000 patients, at the public university hospital at Rio de Janeiro, Brazil, have undergone papain treatment and presented satisfactory results. Despite its extensive use, there is little information about toxic and mutagenic properties of papain. This work evaluated the toxic and mutagenic potential of papain and its potential antioxidant activity against induced-H2O2 oxidative stress in Escherichia coli strains. Cytotoxicity assay, Growth inhibition test, WP2-Mutoxitest and Plasmid-DNA treatment, and agarose gel electrophoresis were used to investigate if papain would present any toxic or mutagenic potential as well as if papain would display antioxidant properties. Papain exhibited negative results for all tests. This agent presented an activity protecting cells against H2O2-induced mutagenesis

Gene and protein expression in response to different growth temperatures and oxygen availability in Burkholderia thailandensis.

Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tThis is the final version of the article. Available from Public Library of Science via the DOI in this record.Burkholderia thailandensis, although normally avirulent for mammals, can infect macrophages in vitro and has occasionally been reported to cause pneumonia in humans. It is therefore used as a model organism for the human pathogen B. pseudomallei, to which it is closely related phylogenetically. We characterized the B. thailandensis clinical isolate CDC2721121 (BtCDC272) at the genome level and studied its response to environmental cues associated with human host colonization, namely, temperature and oxygen limitation. Effects of the different growth conditions on BtCDC272 were studied through whole genome transcription studies and analysis of proteins associated with the bacterial cell surface. We found that growth at 37°C, compared to 28°C, negatively affected cell motility and flagella production through a mechanism involving regulation of the flagellin-encoding fliC gene at the mRNA stability level. Growth in oxygen-limiting conditions, in contrast, stimulated various processes linked to virulence, such as lipopolysaccharide production and expression of genes encoding protein secretion systems. Consistent with these observations, BtCDC272 grown in oxygen limitation was more resistant to phagocytosis and strongly induced the production of inflammatory cytokines from murine macrophages. Our results suggest that, while temperature sensing is important for regulation of B. thailandensis cell motility, oxygen limitation has a deeper impact on its physiology and constitutes a crucial environmental signal for the production of virulence factors.This work was supported by Fondazione CARIPLO (Progetto Vaccini, contract number 2009–3577) and by Ministero dell’Istruzione, dell’Università e della Ricerca (MIUR) (project FIRB RBLA039LSF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Processing of sweet and bitter cassava.

bitstream/item/220876/1/CARTILHA-AIPIM-INGLES-online-AINFO.pd