Gas injection laboratory experiments on Opalinus clay.

Understanding gas transport processes is one of the key issues in the assessment of radioactive waste repository performance and is the focus of this research. To this aim, this research programme was started with the following specific objectives. 1) To develop and calibrate an experimental set-up to perform controlled flow-rate gas injection experiments using a high-pressure triaxial cell to apply isotropic/anisotropic stress states. 2) To carry out a series of tests on Opalinus clay OPA samples to study the conditions under which gas breakthrough processes occur, to analyse the influence of the gas injection rate, the stress state, the orientation of rock discontinuities and other relevant hydro-mechanical variables (porosity, degree of saturation, …), as well as the observation of the induced desaturation (pore water displacement by gas), ingoing and outgoing gas fluxes, aperture and preferential paths created, and so on.Peer ReviewedPostprint (author’s final draft

Extension Theory and Krein-type Resolvent Formulas for Nonsmooth Boundary Value Problems

For a strongly elliptic second-order operator $A$ on a bounded domain $\Omega\subset \mathbb{R}^n$ it has been known for many years how to interpret the general closed $L_2(\Omega)$-realizations of $A$ as representing boundary conditions (generally nonlocal), when the domain and coefficients are smooth. The purpose of the present paper is to extend this representation to nonsmooth domains and coefficients, including the case of H\"older $C^{\frac32+\varepsilon}$-smoothness, in such a way that pseudodifferential methods are still available for resolvent constructions and ellipticity considerations. We show how it can be done for domains with $B^\frac32_{p,2}$-smoothness and operators with $H^1_q$-coefficients, for suitable $p>2(n-1)$ and $q>n$. In particular, Kre\u\i{}n-type resolvent formulas are established in such nonsmooth cases. Some unbounded domains are allowed.Comment: 62 page

Self-starting, self-regulating Fourier domain mode locked fiber laser for OCT imaging

We present a Fourier domain mode locking (FDML) fiber laser with a feedback loop allowing automatic startup without a priori knowledge of the fundamental drive frequency. The feedback can also regulate the drive frequency making the source robust against environmental variations. A control system samples the energy of the light traversing the FDML cavity and uses a voltage controlled oscillator (VCO) to drive the tunable fiber Fabry-Perot filter in order to maximize that energy. We demonstrate a prototype self-starting, self-regulating FDML operating at 40 kHz with a full width tuning range of 140 nm around 1305 nm and a power output of ~40 mW. The laser starts up with no operator intervention in less than 5 seconds and exhibits improved spectral stability over a conventional FDML source. In OCT applications the source achieved over 120 dB detection sensitivity and an ~8.9-µm axial resolution

As Ciências da Natureza na Educação Infantil a partir de uma proposta de Estágio Supervisionado

Objetivou-se analisar a presença das temáticas da área das Ciências da Natureza (CN) na Educação Infantil (EI) em uma proposta de estágio supervisionado do curso de Pedagogia. O estudo é de abordagem qualitativa, de cunho bibliográfico e documental, tendo como material de análise o relatório de estágio em EI de uma acadêmica do curso de Pedagogia de uma instituição brasileira. Para a análise dos dados, partiu-se de duas categorias pré-estabelecidas: Campos de Experiências (CE) para a EI orientados pelos documentos oficiais e os eixos temáticos/atividades desenvolvidas da área das CN. Constatou-se que a estagiária procurou atingir os CE sugeridos pelos documentos oficiais (Brasil, 2010; Brasil, 2016) e as CN estiveram presentes na proposta a partir de eixos temáticos e atividades, envolvendo: ser humano e saúde, ambiente e materiais e transformações

Reactive oxygen species metabolism and plant-fungal interactions

Fungal interactions with plants can involve specific morphogenetic developments to access host cells, the suppression of plant defenses, and the establishment of a feeding lifestyle that nourishes the colonizer often—but not always—at the expense of the host. Reactive oxygen species (ROS) metabolism is central to the infection process, and the stage-specific production and/or neutralization of ROS is critical to the success of the colonization process. ROS metabolism during infection is dynamic—sometimes seemingly contradictory—and involves endogenous and exogenous sources. Yet, intriguingly, molecular decision-making involved in the spatio-temporal control of ROS metabolism is largely unknown. When also considering that ROS demands are similar between pathogenic and beneficial fungal-plant interactions despite the different outcomes, the intention of our review is to synthesize what is known about ROS metabolism and highlight knowledge gaps that could be hindering the discovery of novel means to mediate beneficial plant-microbe interactions at the expense of harmful plant-microbe interactions

Eficiência de controle de Brachiaria ruziziensis com glyphosate em função de adjuvante e dose.

bitstream/item/111652/1/38-eficiencia-felipe.pd