24,106 research outputs found

    Efeito de pesticidas aos polinizadores do guaranazeiro: avaliação da toxicidade aguda de inseticidas às abelhas (Hymenoptera: Apidae).

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    Neste trabalho foi avaliada a sensibilidade da espécie de abelha Melipona seminigra, nativa da Amazônia, ao inseticida Parathion metil

    Graded-index optical fiber emulator of an interacting three-atom system: illumination control of particle statistics and classical non-separability

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    We show that a system of three trapped ultracold and strongly interacting atoms in one-dimension can be emulated using an optical fiber with a graded-index profile and thin metallic slabs. While the wave-nature of single quantum particles leads to direct and well known analogies with classical optics, for interacting many-particle systems with unrestricted statistics such analoga are not straightforward. Here we study the symmetries present in the fiber eigenstates by using discrete group theory and show that, by spatially modulating the incident field, one can select the atomic statistics, i.e., emulate a system of three bosons, fermions or two bosons or fermions plus an additional distinguishable particle. We also show that the optical system is able to produce classical non-separability resembling that found in the analogous atomic system.Comment: 14 pages, 5 figure

    Effect of wood aging on wine mineral composition and 87Sr/86Sr isotopic ratio

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    The evolution of mineral composition and wine strontium isotopic ratio 87Sr/86Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60, and 90 days of aging, and the wines were evaluated in terms of general analysis, phenolic composition, total polysaccharides, multielement composition, and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, and Pb elements and 87Sr/86Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and Na, K, Ca, and Fe by flame atomic absorption spectrometry (FAAS). Two-way ANOVA was applied to assess wood aging and time effect on Sr IR and mineral composition. Wood aging resulted in significantly higher concentrations of Mg, V, Co, Ni, and Sr. At the end of the aging period, wine exhibited statistically identical Sr IR compared to control. Study suggests that wood aging does not affect 87Sr/86Sr, not precluding the use of this parameter for wine traceability purposesinfo:eu-repo/semantics/publishedVersio

    Efeito de inseticidas reguladores de crescimento sobre ovos, lagartas e adultos de Grapholita molesta (BUSCK) (LEP.: Tortricidae).

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    O trabalho teve como objetivo avaliar o efeito de inseticidas reguladores de crescimento de insetos (RCI) sobre ovos, lagartas e adultos de G. molesta, em laboratório. Os inseticidas avaliados foram lufenurom e novalurom (4,0g de i.a. 100L-1) metoxifenozida e tebufenozida (9,6g de i.a. 100L-1) e uma testemunha (água destilada). Em aplicação antes da oviposição, somente o metoxifenozida causou mortalidade significativa de ovos (26,3%), quando comparado à testemunha. A aplicação dos inseticidas sobre ovos com diferentes idades (24; 48 e 72 horas) apresentou variações na mortalidade da espécie em função do inseticida e tempo de desenvolvimento embrionário. Somente metoxifenozida e novalurom reduziram a viabilidade de lagartas que eclodiram dos ovos tratados, com um máximo de 35,9 e 39,5% de viabilidade larval quando aplicados em ovos de 48-72 horas, respectivamente. O tratamento dos frutos de maçã com inseticidas causou mortalidade significativa das lagartas, contudo não foram observadas diferenças entre os inseticidas, tanto para lagartas pequenas (eficiência média de 47,2%), quanto para lagartas de 3º-4º instar (média de 45,3%). Lufenurom reduziu sua eficácia com o aumento do tamanho da lagarta. A ingestão de lufenurom, metoxifenozida, novalurom, tebufenozida por adultos de G. molesta reduziu a fecundidade e a fertilidade, porém a longevidade dos adultos somente foi afetada negativamente pela ingestão de metoxifenozida e tebufenozida

    Improving the quality of Portuguese SMEs through competence evaluation

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    UIDB/04647/2020 UIDP/04647/2020Problem and goal. Since we are going through a key moment in terms of technological advances and their effect on the labour field, the investigation of the on-the-job training processes gains a predominant role. Moreover, the need to research an approach that promotes a balance between the four spheres of development of learning – economic, sustain-able, community and personal – is emerging. This study was conceived as a result of this ur-gency, aiming to respond to the following problem: to what extent does a training model, based on the VPL (Validation of Prior Learning) approach and supported by principles of the educational sciences, can contribute to individual empowerment and, consequently, to an improvement in the organizational quality of Portuguese SMEs (Small and Medium-sized Enterprises)? Methodology. The division of the research into two parts – Study 1 and Study 2 – al-lowed the collection and analysis of structural data (Study 1) that served as a basis for the defi- nition of a dynamic strategy (Study 2). Although undertaken at different times, they have thus proved to be complementary. In fact, the design of the training model was based, firstly, on the results obtained through exploratory interviews with key informants and, secondly, on the data obtained throughout the training process that involved ninety-two employees from ten Portuguese SMEs from diverse categories and sectors. Results. The training model, which emerged from the interaction between the theoreti-cal reflection and the practical context, comprises five components: distance learning, recog-nition of skills, language skills, intercultural skills and an individual action plan. Conclusion. This study, being an important contribution to the topic of on-the-job training in Portuguese SMEs, at the same time opens the way for the continuation of the research.publishersversionpublishe
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