Perfect Fluid Quantum Anisotropic Universe: Merits and Challenges

The present paper deals with quantization of perfect fluid anisotropic cosmological models. Bianchi type V and IX models are discussed following Schutz's method of expressing fluid velocities in terms of six potentials. The wave functions are found for several examples of equations of state. In one case a complete wave packet could be formed analytically. The initial singularity of a zero proper volume can be avoided in this case, but it is plagued by the usual problem of non-unitarity of anisotropic quantum cosmological models. It is seen that a particular operator ordering alleviates this problem.Comment: 13 pages, 4 figures; Accepted for publication in Gen Relativ Gravi

Isolation and functional characterization of a cotton ubiquitination-related promoter and 5'UTR that drives high levels of expression in root and flower tissues

<p>Abstract</p> <p>Background</p> <p>Cotton (<it>Gossypium </it>spp.) is an important crop worldwide that provides raw material to 40% of the textile fiber industry. Important traits have been studied aiming the development of genetically modified crops including resistance to insect and diseases, and tolerance to drought, cold and herbicide. Therefore, the characterization of promoters and regulatory regions is also important to achieve high gene expression and/or a specific expression pattern. Commonly, genes involved in ubiquitination pathways are highly and differentially expressed. In this study, we analyzed the expression of a cotton ubiquitin-conjugating enzyme (E2) family member with no previous characterization.</p> <p>Results</p> <p>Nucleotide analysis revealed high identity with cotton <it>E2 </it>homologues. Multiple alignment showed a premature stop codon, which prevents the encoding of the conserved cysteine residue at the <it>E2 </it>active site, and an intron that is spliced in <it>E2 </it>homologues, but not in <it>GhGDRP85</it>. The <it>GhGDRP85 </it>gene is highly expressed in different organs of cotton plants, and has high transcript levels in roots. Its promoter (uceApro2) and the 5'UTR compose a regulatory region named uceA1.7, and were isolated from cotton and studied in <it>Arabidopsis thaliana</it>. uceA1.7 shows strong expression levels, equaling or surpassing the expression levels of CaMV35S. The uceA1.7 regulatory sequence drives GUS expression 7-fold higher in flowers, 2-fold in roots and at similar levels in leaves and stems. GUS expression levels are decreased 7- to 15-fold when its 5'UTR is absent in uceApro2.</p> <p>Conclusions</p> <p>uceA1.7 is a strong constitutive regulatory sequence composed of a promoter (uceApro2) and its 5'UTR that will be useful in genetic transformation of dicots, having high potential to drive high levels of transgene expression in crops, particularly for traits desirable in flower and root tissues.</p

Determinants of the income velocity of money in Portugal: 1891–1998

This paper performs a long-run time series analysis of the behaviour of the income velocity of money in Portugal between 1891 and 1998 by assessing the importance of both macroeconomic and institutional factors and looking for particularities in the Portuguese case. We estimate two cointegration vectors for the income velocity of money, macroeconomic variables and institutional variables. It is apparent that one of these vectors reflects the relationship between income velocity and macroeconomic variables, while the other reflects the relationship between income velocity and institutional variables. Moreover, a regression analysis reveals that the usual U-shaped pattern is displayed with a relatively late inflection point located around 1970, which is consistent with the Spanish case. It is further noted that this is a feature of countries with a late economic and institutional development process.info:eu-repo/semantics/publishedVersio

Dimensional reduction at a quantum critical point

Competition between electronic ground states near a quantum critical point (QCP) - the location of a zero-temperature phase transition driven solely by quantum-mechanical fluctuations - is expected to lead to unconventional behaviour in low-dimensional systems. New electronic phases of matter have been predicted to occur in the vicinity of a QCP by two-dimensional theories, and explanations based on these ideas have been proposed for significant unsolved problems in condensed-matter physics, such as non-Fermi-liquid behaviour and high-temperature superconductivity. But the real materials to which these ideas have been applied are usually rendered three-dimensional by a finite electronic coupling between their component layers; a two-dimensional QCP has not been experimentally observed in any bulk three-dimensional system, and mechanisms for dimensional reduction have remained the subject of theoretical conjecture. Here we show evidence that the Bose-Einstein condensate of spin triplets in the three-dimensional Mott insulator BaCuSi2O6 provides an experimentally verifiable example of dimensional reduction at a QCP. The interplay of correlations on a geometrically frustrated lattice causes the individual two-dimensional layers of spin-1/2 Cu2+ pairs (spin dimers) to become decoupled at the QCP, giving rise to a two-dimensional QCP characterized by power law scaling distinctly different from that of its three-dimensional counterpart. Thus the very notion of dimensionality can be said to acquire an 'emergent' nature: although the individual particles move on a three-dimensional lattice, their collective behaviour occurs in lower-dimensional space.Comment: 14 pages, 4 figure

Estado nutricional e uso de suplementos alimentares por acadêmicos de Nutrição da Universidade Federal do Tocantins

Os estudos sobre o consumo de suplementos alimentares por frequentadores de academias são encontrados em maior número na literatura científica, no entanto, há poucos dados sobre o perfil de consumo destes produtos por universitários ou pela população em geral. Dessa forma, este estudo buscou conhecer a prevalência do uso de suplementos associado ao estado nutricional e percepção corporal de acadêmicos do curso de nutrição. Para obtenção dos resultados foi aplicado um questionário de múltipla escolha, e realizada antropometria em 50 indivíduos de ambos os sexos, com idade de 18 a 35 anos, escolhidos aleatoriamente. Dessa amostra obteve-se que 50% dos estudantes entrevistados utilizavam suplemento alimentar, sendo vitaminas e minerais, ricos em proteínas e fitoterápicos os mais utilizados. Aproximadamente, 26% utilizavam por iniciativa própria. Quanto ao estado nutricional, 72% estavam eutróficos e 74% realizavam alguma atividade física, no entanto, não estavam satisfeitos com o corpo (74%). Sugere-se que a influência do conhecimento científico presente na ciência da nutrição influencie os acadêmicos quanto a alimentação saudável, no entanto, a mesma não está baseada apenas na ingestão de nutrientes específicos e sim na ingestão dos alimentos in natura, com foco nos hábitos alimentares regionais e bem-estar biopsicossocial, fato destoante neste trabalho. Além disso, enfatiza-se sobre a variabilidade da vida dos acadêmicos, embora existam vários meios de se obter uma alimentação saudável, existem vários fatores que podem interferir em uma alimentação variada e balanceada, fazendo assim com que os mesmos invistam na utilização de suplementos alimentares. ABSTRACT Nutritional status and use of food supplements by academics of nutrition of the Federal University of TocantinsStudies on the consumption of dietary supplements by academics are found in greater numbers in the scientific literature, however, there is little data on the profile of consumption of these products by university students or by the general population. Thus, this study sought to know the prevalence of the use of supplements associated with the nutritional status and body perception of the students of the nutrition course. To obtain the results, a multiple-choice questionnaire was applied, and anthropometry was performed in 50 individuals of both sexes, aged 18 to 35 years, randomly selected. From this sample, it was obtained that 50% of the students interviewed used food supplement, being vitamins and minerals, rich in proteins and phototherapy the most used. Approximately 26% used it on their own initiative. Regarding nutritional status, 72% were eutrophic and 74% had some physical activity, however, they were not satisfied with the body (74%). It is suggested that the influence of scientific knowledge present in the science of nutrition influences the academic about healthy eating, however, it is based not only on the ingestion of specific nutrients but on the ingestion of in nature foods, focusing on eating habits And bio psychosocial well-being, a fact that is dis- In addition, emphasis is placed on the variability of academic life, although there are several ways to achieve healthy eating, there are several factors that can interfere with a varied and balanced diet, thus making them invest in the use of food supplements

High ultraviolet C resistance of marine Planctomycetes

Planctomycetes are bacteria with particular characteristics such as internal membrane systems encompassing intracellular compartments, proteinaceous cell walls, cell division by yeast-like budding and large genomes. These bacteria inhabit a wide range of habitats, including marine ecosystems, in which ultra-violet radiation has a potential harmful impact in living organisms. To evaluate the effect of ultra-violet C on the genome of several marine strains of Planctomycetes, we developed an easy and fast DNA diffusion assay in which the cell wall was degraded with papain, the wall-free cells were embedded in an agarose microgel and lysed. The presence of double strand breaks and unwinding by single strand breaks allow DNA diffusion, which is visible as a halo upon DNA staining. The number of cells presenting DNA diffusion correlated with the dose of ultra-violet C or hydrogen peroxide. From DNA damage and viability experiments, we found evidence indicating that some strains of Planctomycetes are significantly resistant to ultra-violet C radiation, showing lower sensitivity than the known resistant Arthrobacter sp. The more resistant strains were those phylogenetically closer to Rhodopirellula baltica, suggesting that these species are adapted to habitats under the influence of ultra-violet radiation. Our results provide evidence indicating that the mechanism of resistance involves DNA damage repair and/or other DNA ultra-violet C-protective mechanism.This research was supported by the European Regional Development Fund (ERDF) through the COMPETE-Operational Competitiveness Programme and national funds through FCT-Foundation for Science and Technology, under the projects Pest-C/BIA/UI4050/2011 and PEst-C/MAR/LA0015/2013. We are grateful to Catia Moreira for helping with the extraction of the pigments.info:eu-repo/semantics/publishedVersio