Natural convection in a shallow cavity with differentially heated end walls. Part 2. Numerical solutions

Numerical solutions of the full Navier-Stokes equations are obtained for the problem of natural convection in closed cavities of small aspect ratio with differentially heated end walls. These solutions cover the parameter range Pr = 6.983, 10 ≤ Gr ≤ 2x10^4 and 0.05 ≤ A ≤ 1. A comparison with the asymptotic theory of part 1 shows excellent agreement between the analytical and numerical solutions provided that A ≾ 0.1 and Gr^2A^3Pr^2 ≾ l0^5. In addition, the numerical solutions demonstrate the transition between the shallow-cavity limit of part 1 and the boundary-layer limit; A fixed, Gr → ∞

Kinetic modelling of epitaxial film growth with up- and downward step barriers

The formation of three-dimensional structures during the epitaxial growth of films is associated to the reflection of diffusing particles in descending terraces due to the presence of the so-called Ehrlich-Schwoebel (ES) barrier. We generalize this concept in a solid-on-solid growth model, in which a barrier dependent on the particle coordination (number of lateral bonds) exists whenever the particle performs an interlayer diffusion. The rules do not distinguish explicitly if the particle is executing a descending or an ascending interlayer diffusion. We show that the usual model, with a step barrier in descending steps, produces spurious, columnar, and highly unstable morphologies if the growth temperature is varied in a usual range of mound formation experiments. Our model generates well-behaved mounded morphologies for the same ES barriers that produce anomalous morphologies in the standard model. Moreover, mounds are also obtained when the step barrier has an equal value for all particles independently if they are free or bonded. Kinetic roughening is observed at long times, when the surface roughness w and the characteristic length $\xi$ scale as $w ~ t^\beta$ and $\xi ~ t^\zeta$ where $\beta \approx 0.31$ and $\zeta \approx 0.22$, independently of the growth temperature.Comment: 15 pages, 7 figure

Aspects of CPT-even Lorentz-symmetry violating physics in a supersymmetric scenario

Background fermion condensates in a landscape dominated by global SUSY are reassessed in connection with a scenario where Lorentz symmetry is violated in the bosonic sector (actually, the photon sector) by a $CPT$-even $k_F$-term. An effective photonic action is discussed that originates from the supersymmetric background fermion condensates. Also, the photino mass emerges in terms of a particular condensate contrary to what happens in the $k_{AF}$-violation. Finally, the interparticle potential induced by the effective photonic action is investigated and a confining profile is identified.Comment: 14 pages. arXiv admin note: text overlap with arXiv:1102.3777 by other author

Evaluating recommended audiometric changes to candidacy using the speech intelligibility index

INTRODUCTION: The National Institute of Health and Care Excellence (NICE) has derived candidacy guidelines for cochlear implants in the UK based on audiometric thresholds (90 dB HL or above at 2 and 4 kHz; hereafter referred to as the 90 dB HL criteria). Recent research has proposed that these criteria should be changed to 80 dB HL at 2 and 4 kHz (hereafter referred to as the 80 dB HL criteria) in the ear to be implanted. METHODS: In this study, we analysed aided SII scores derived for different hearing loss profiles falling within the current 90 dB HL criteria and equivalent profiles falling within the new 80 dB HL criteria. RESULTS: The aided SII scores demonstrated that the majority of potential hearing configurations falling within the new proposed 80 dB HL criteria have aided SII values of less than 0.65 (a recommended cut-off point below which there is not sufficient audibility to receive adequate benefit through hearing aids). CONCLUSIONS: This supports the proposed change to the 80 dB HL criterion level and also highlights the additional value of the SII score in supporting candidacy decisions for CI, especially for borderline candidates

Surface-Invariants in 2D Classical Yang-Mills Theory

We study a method to obtain invariants under area-preserving diffeomorphisms associated to closed curves in the plane from classical Yang-Mills theory in two dimensions. Taking as starting point the Yang-Mills field coupled to non dynamical particles carrying chromo-electric charge, and by means of a perturbative scheme, we obtain the first two contributions to the on shell action, which are area-invariants. A geometrical interpretation of these invariants is given.Comment: 17 pages, 2 figure

Parenting desires, parenting intentions, and anticipation of stigma upon parenthood among lesbian, bisexual and heterosexual women in Portugal

We explored parenting desires, parenting intentions, and anticipation of stigma upon parenthood in a sample of 257 self-identified lesbian, bisexual, and heterosexual childfree women in Portugal. No differences between the groups were observed concerning parenting desires. However, lesbian and bisexual women reported lower intentions to have children than their heterosexual counterparts. Although lesbian women considered themselves to have a higher chance of being victims of social stigma as mothers, this was not associated with their parenting desires. Furthermore, younger lesbian women intended to have children to a greater extent than did older lesbian women; relational status did not relate to lesbian women’s parenting intentions, desires, or anticipation of stigma. Overall, this study contributes to knowledge about family formation processes among Portuguese women diverse in sexual identity

Formation of Nanopillar Arrays in Ultrathin Viscous Films: The Critical Role of Thermocapillary Stresses

Experiments by several groups during the past decade have shown that a molten polymer nanofilm subject to a large transverse thermal gradient undergoes spontaneous formation of periodic nanopillar arrays. The prevailing explanation is that coherent reflections of acoustic phonons within the film cause a periodic modulation of the radiation pressure which enhances pillar growth. By exploring a deformational instability of particular relevance to nanofilms, we demonstrate that thermocapillary forces play a crucial role in the formation process. Analytic and numerical predictions show good agreement with the pillar spacings obtained in experiment. Simulations of the interface equation further determine the rate of pillar growth of importance to technological applications.Comment: 5 pages, 4 figure

Desorption Dynamics of Heavy Alkali Metal Atoms (Rb, Cs) off the Surface of Helium Nanodroplets

We present a combined ion imaging and density functional theory study of the dynamics of the desorption process of rubidium and cesium atoms off the surface of helium nanodroplets upon excitation of the perturbed $6s$ and $7s$ states, respectively. Both experimental and theoretical results are well represented by the pseudodiatomic model for effective masses of the helium droplet in the desorption reaction of m_eff/m_He~10 (Rb) and 13 (Cs). Deviations from this model are found for Rb excited to the 6p state. Photoelectron spectra indicate that the dopant-droplet interaction induces relaxation into low-lying electronic states of the desorbed atoms in the course of the ejection process.Comment: in press, J. Phys. Chem. A (2014

Blog sobre legislação ambiental brasileira na Embrapa: a informação ao alcance de todos.

A legislação ambiental brasileira visa fiscalizar e punir aquele que causa dano ao meio ambiente, bem como garantir qualidade de vida e sustentabilidade ambiental para todos. Através de meios eletrônicos é possível obter informações da legislação brasileira. A disponibilidade em meios eletrônicos, especialmente internet, facilita o acesso da população às leis, levando a todos a conscientização das legislações existentes no Brasil. O objetivo desta pesquisa é reunir, classificar e disponibilizar a legislação ambiental, de forma fácil e clara, ao alcance e acesso a toda população. O acesso pode ser feito através de um link que será disponibilizado no site da Embrapa Gado de Corte. Ao acessar a página, o visitante visualiza a legislação ambiental que foi dividida por assuntos. Disponibiliza-se também a sinopse da lei, o número da legislação e o texto da legislação na íntegra através de hiperlink. Este é interligado e direcionado a um site do governo federal, que atualiza regularmente todas as legislações. No site da Embrapa será disponibilizado o acesso de diversas normas jurídicas e administrativas, de âmbito ambiental para pesquisas e download. Hoje temos, relacionado com a legislação ambiental, registros de 37 Leis, 18 Decretos, dois Decreto-Lei, 10 Portarias Normativas do IBAMA, 33 Resoluções do Conama, uma Portaria IPHAN, uma Instrução Normativa MMA, duas Portarias do Ibama, uma Portaria do Ministério da Saúde, uma Resolução RDC e a Constituição da República Federativa do Brasil de 1988. As normas jurídicas ambientais têm como objetivo disciplinar atividades humanas, para torná-las compatível com a proteção do meio ambiente. A pesquisa procura conscientizar a existência das leis ambientais, facilitando e disponibilizando seu acesso pela internet na página da Embrapa. A educação e informações direcionadas e especializadas, como a proposta desta pesquisa, pode auxiliar na transformação do ambiente em que vivemos, além de contribuir na pesquisa educacional dos interessados

A Thorn in a Haystack: A Rare Case of Septic Arthritis

Pantoea agglomerans is a facultative anaerobe and environmental bacterium that could be a cause of opportunistic human infections, especially in wound infection with plant material. Arthritis or synovitis secondary to penetrating plant thorn injuries is not frequently reported. We present the case of a 35-year-old otherwise healthy male with a bramble thorn penetrating injury of the left knee. P. agglomerans was isolated from the synovial fluid. The patient was treated with amoxicillin/clavulanate according to sensitivity testing. This case highlights the importance of precise and thorough medical history, especially for less common presentations, as well as source control.info:eu-repo/semantics/publishedVersio