Surface and Bulk Structural Properties of Single Crystalline Sr3Ru2O7

We report temperature and thermal-cycling dependence of surface and bulk structures of double-layered perovskite Sr3Ru2O7 single crystals. The surface and bulk structures were investigated using low-energy electron diffraction (LEED) and single-crystal X-ray diffraction (XRD) techniques, respectively. Single-crystal XRD data is in good agreement with previous reports for the bulk structure with RuO6 octahedral rotation, which increases with decreasing temperature (~ 6.7(6)degrees at 300 K and ~ 8.1(2) degrees at 90 K). LEED results reveal that the octahedra at the surface are much more distorted with a higher rotation angle (~ 12 degrees between 300 and 80 K) and a slight tilt ((4.5\pm2.5) degrees at 300 K and (2.5\pm1.7) degrees at 80 K). While XRD data confirms temperature dependence of the unit cell height/width ratio (i.e. lattice parameter c divided by the average of parameters a and b) found in a prior neutron powder diffraction investigation, both bulk and surface structures display little change with thermal cycles between 300 and 80 K.Comment: 25 pages, 5 figures, 5 tables, to appear in Physical Review

Desenvolvimento de um programa integrado de controle dos nematodeos e a mosca-dos-chifres, na região dos cerrados. fase 3. potencial de onthophagus gazella no enterrio de fezes bovinas.

Onthophagus gazella; Solo; Microbiologia.bitstream/item/137591/1/PESQ-EM-ANDAMENTO-42.pdfCNPGC

On the stability of solutions of semilinear elliptic equations with Robin boundary conditions on Riemannian manifolds

We investigate existence and nonexistence of stationary stable nonconstant solutions, i.e. patterns, of semilinear parabolic problems in bounded domains of Riemannian manifolds satisfying Robin boundary conditions. These problems arise in several models in applications, in particular in Mathematical Biology. We point out the role both of the nonlinearity and of geometric objects such as the Ricci curvature of the manifold, the second fundamental form of the boundary of the domain and its mean curvature. Special attention is devoted to surfaces of revolution and to spherically symmetric manifolds, where we prove refined results

Doação e transplantes de órgãos: Contribuições dos profissionais sobre o trabalho interprofissional nos programas

Objective: This study aimed to identify the contributions for improvement in the interprofessional working relationship pointed out by professionals involved in organ and tissue procurement and transplantation programs. Method: exploratory study with a quantiqualitative approach conducted over a period of 21 months, with the participation of health professionals invited to complete an online questionnaire on the Google form platform. After collection, the quantitative data were organized and analyzed descriptively, and the qualitative data were categorized and submitted to content analysis. Results: 130 health professionals participated in the study, 84% were female, of which 64% said they were white, between 41-59 years old, and 31% had worked for more than 15 years in the programs. The categories identified were: working conditions; appreciation of non-medical professionals; psychological support to professionals and funding for training of professionals pointed out as improvements in the work relationship in the programs. Conclusion: the study identified that working conditions and greater valorization of the interprofessional team allied to offering psychological support to professionals are necessary and important strategies, and may bring impacts on the satisfaction of professionals, on mental health, in addition to improvements in work processes, impacting transplantation rates.Objetivo: Com este estudo, objetivou-se identificar as contribuições de melhoria na relação de trabalho interprofissional apontadas por profissionais envolvidos nos programas de procura e de transplantação de órgãos e tecidos. Método: estudo exploratório com abordagem quanti-qualitativo realizado no período de 21 meses, com a participação de profissionais da área da saúde convidados a preencher um questionário online da plataforma de formulários do Google. Após a coleta, organizaram-se os dados quantitativos, analisando-os de maneira descritiva e, em categorias, os dados qualitativos, submetendo-os à análise de conteúdo. Resultados:participaram do estudo 130 profissionais de saúde, sendo 84% do gênero feminino, dos quais 64% se declararam de cor de pele branca; de faixa etária entre 41–59 anos, sendo que (31%) trabalhavam há mais de quinze anos nos programas. As categorias identificadas foram: condições de trabalho; valorização dos profissionais não médicos; suporte psicológico e financiamento para capacitação dos profissionais apontadas como melhorias na relação de trabalho nos programas. Conclusão: o estudo possibilitou identificar que na relação de trabalho as condições laborais e maior valorização da equipe interprofissional aliadas ao oferecimento de suporte psicológico aos profissionais são estratégias necessárias, podendo trazer impactos na satisfação dos profissionais, na saúde mental, além de melhorias nos processos de trabalho, impactando as taxas de transplantes.info:eu-repo/semantics/publishedVersio

The solar, exoplanet and cosmological lithium problems

We review three Li problems. First, the Li problem in the Sun, for which some previous studies have argued that it may be Li-poor compared to other Suns. Second, we discuss the Li problem in planet hosting stars, which are claimed to be Li-poor when compared to field stars. Third, we discuss the cosmological Li problem, i.e. the discrepancy between the Li abundance in metal-poor stars (Spite plateau stars) and the predictions from standard Big Bang Nucleosynthesis. In all three cases we find that the "problems" are naturally explained by non-standard mixing in stars.Comment: Astrophysics and Space Science, in press. New version has one reference correcte

Efeito da radiação ultravioleta B sobre a diversidade de leveduras epifíticas associadas ao morango.

Resumo: Nos últimos anos tem sido observado um aumento na radiação ultravioleta B que atinge a superfície terrestre, sendo este comprimento de onda o mais prejudicial para moléculas biologicamente ativas. As superfícies foliares estão constantemente expostas a esta radiação, podendo afetar de forma significativa os micro-organismos que ocupam este nicho. As células de leveduras epifíticas foram removidas das folhas do morango após a incidência de radiação UV-B em condições de campo em diferentes tempos de exposição. A contagem de unidades formadoras de colônia mostrou padrões de pigmentação diferentes em cada tratamento, indicando que tais estruturas atuam como mecanismos de proteção a radiação. A análise com T-RFLP não mostrou diferenças quanto à diversidade de leveduras nos diferentes tratamentos. Abstract: In the last few years have been observed an increasing ultraviolet radiation B that reaches the land surface, this wave length is the most damaging to the biologically molecules active. The leaf surfaces are constantly exposed to this radiation that can significantly affect the microorganisms that belong to this niche. The epiphytic yeasts were removed from the strawberry leaves after the UV-B radiation incidence under field conditions in different time exposition. The counting of colony forming units showed different pigmentation patterns in each treatment, indicating that these structures act like protection mechanisms against the radiation. Analysis using T-RFLP showed no differences in the diversity of yeasts in the distinct treatments

Lpg-based Sensor For Curvature And Vibration

A long-period grating (LPG) written on a standard single mode fiber is investigated as a curvature and vibration sensor. It is demonstrated a high sensitivity to applied curvature and the possibility to monitor vibration in a wide range of frequencies from 30 Hz to 2000 Hz. The system was tested using an intensity based interrogation scheme with the LPG sensor operating in the curvature regime. Results have shown a reproducible frequency discrimination in the 30 Hz to 2000 Hz, with resolutions between 11 mHz and 913 mHz. Frequency retrieval could be perfouned independent of temperature up to 86 degrees C.99166th European Workshop on Optical Fibre SensorsMAY 31-JUN 03, 2016Univ Limerick, Limerick, IRELAN

Avaliação de giberela em genótipos de triticale.

Editores técnicos: Joseani Mesquita Antunes, Ana Lídia Variani Bonato, Márcia Barrocas Moreira Pimentel

Realization of Rectangular Artificial Spin Ice and Direct Observation of High Energy Topology

In this letter, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by $a$ and $b$ respectively). Arrays with three different ratios $\gamma =a/b = \sqrt{2}$, $\sqrt{3}$ and $\sqrt{4}$ are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough $\gamma$. Our results also insinuate that magnetic monopoles may be almost free in rectangular lattices with a critical ratio $\gamma = \gamma_{c} = \sqrt{3}$, supporting previous theoretical predictions

Impact of COVID-19 on clinical trials and clinical research: A systematic review

Background: The World Health Organization has reported more than 31,186,000 confirmed cases of coronavirus disease-19 (COVID-19), including 962,343 deaths, worldwide as on September 21, 2020. The current COVID-19 pandemic is affecting clinical research activities in most parts of the world. The focus on developing a vaccine for SARS-CoV-2 and the treatment of COVID-19 is, in fact, disrupting many upcoming and/or ongoing clinical trials on other diseases around the globe. On March 18, 2020, the United States Food and Drug Administration (FDA) issued an updated guideline for the conduct of clinical trials during the current health emergency situation. The potential challenges, such as social distancing and quarantines, result in study participants’ inaccessibility and trial personnel for in-person scheduled study visits and/or follow-up. Due to the sudden onset and wide-spread impact of COVID-19, its influence on the management of clinical trials and research necessitates urgent attention. Therefore, our systematic review of the literature aims to assess the impact of the COVID-19 pandemic on the conduction of clinical trials and research. The search for the relevant articles for review included the keywords "COVID-19” AND "clinical trial" in PubMed, MEDLINE, Embase, Google scholar and Google electronic databases. Key findings include: delaying subject enrollment and operational gaps in most ongoing clinical trials, which in turn has a negative impact on trial programmes and data integrity. Globally, most sites conducting clinical trials other than COVID-19 are experiencing a delay in timelines and a complete halt of operations in lieu of this pandemic, thus affecting clinical research outcomes