988 resultados para condensation symbol


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In this work we compare the results of the Gross-Pitaevskii and modified Gross-Pitaevskii equations with ab initio variational Monte Carlo calculations for Bose-Einstein condensates of atoms in axially symmetric traps. We examine both the ground state and excited states having a vortex line along the z axis at high values of the gas parameter and demonstrate an excellent agreement between the modified Gross-Pitaevskii and ab initio Monte Carlo methods, both for the ground and vortex states.

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Two-dimentional systems of trapped samples of few cold bosonic atoms submitted to strong rotation around the perpendicular axis may be realized in optical lattices and microtraps. We investigate theoretically the evolution of ground state structures of such systems as the rotational frequency Omega increases. Various kinds of ordered structures are observed. In some cases, hidden interference patterns exhibit themselves only in the pair correlation function; in some other cases explicit broken-symmetry structures appear that modulate the density. For N < 10 atoms, the standard scenario, valid for large sytems is absent, and is only gradually recovered as N increases. On the one hand, the Laughlin state in the strong rotational regime contains ordered structures much more similar to a Wigner molecule than to a fermionic quantum liquid. On the other hand, in the weak rotational regime, the possibility to obtain equilibrium states, whose density reveals an array of vortices, is restricted to the vicinity of some critical values of the rotational frequency Omega.

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The recent identification of several additional members of the family of sugar transport facilitators (gene symbol SLC2A, protein symbol GLUT) has created a heterogeneous and, in part, confusing nomenclature. Therefore, this letter provides a summary of the family members and suggests a systematic nomenclature for SLC2A and GLUT symbols.

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Chapter 21 of the Byzantine work known as The Symbolic Garden refers to an unidentified plant (the smilax) which symbolizes science. The author has taken this symbol from patristic literature (Athanasius of Alexandria and other patristic texts). On the other hand, a passage (p. 71, 17- 73, 1) unti1 now misinterpreted can be understood if confronted with severa1 texts by John Darnascenus and Nicetas Stethatos, who both voice the same opinions about science

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The aim of this article is to present an accurate analysis of O. Wilde's poem 'Camma' by referring it to its Greek model: that Camma both in Plutarch's Amatorius (Eroticus) and Mulierum Virtutes. It is precisely this accurate reading which permits us to verify how Plutarch's Ethics is corrected from the parameters of the hedonism which is peculiar to O. Wilde's aestheticism, thus turning Camma into a symbol of a pleasant life.

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This article pays attention to two moments in the life and work (inseparably united) of Maria-Mercè Marçal. The first refers to a search of small objects presided by the moon. Taking this search as a motif, the freedom which the poet confers to the nocturnal light ¿mythical and magical symbol of femaleness- and, therefore, to that which symbolises the heavenly body, is revealed. The second moment revolves around the reflection of Marçal on the ¿female authority¿, a concept which this author, inspired by the philosophical community of Diotima, distinguishes from power. Throughout history, Maria-Mercè Marçal remarked, many women have gained strength from the free atribution of authority to other women, to their texts, to their experiences.

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PURPOSE: To analyze in vivo the function of chicken acidic leucine-rich epidermal growth factor-like domain containing brain protein/Neuroglycan C (gene symbol: Cspg5) during retinal degeneration in the Rpe65⁻/⁻ mouse model of Leber congenital amaurosis. METHODS: We resorted to mice with targeted deletions in the Cspg5 and retinal pigment epithelium protein of 65 kDa (Rpe65) genes (Cspg5⁻/⁻/Rpe65⁻/⁻). Cone degeneration was assessed with cone-specific peanut agglutinin staining. Transcriptional expression of rhodopsin (Rho), S-opsin (Opn1sw), M-opsin (Opn1mw), rod transducin α subunit (Gnat1), and cone transducin α subunit (Gnat2) genes was assessed with quantitative PCR from 2 weeks to 12 months. The retinal pigment epithelium (RPE) was analyzed at P14 with immunodetection of the retinol-binding protein membrane receptor Stra6. RESULTS: No differences in the progression of retinal degeneration were observed between the Rpe65⁻/⁻ and Cspg5⁻/⁻/Rpe65⁻/⁻ mice. No retinal phenotype was detected in the late postnatal and adult Cspg5⁻/⁻ mice, when compared to the wild-type mice. CONCLUSIONS: Despite the previously reported upregulation of Cspg5 during retinal degeneration in Rpe65⁻/⁻ mice, no protective effect or any involvement of Cspg5 in disease progression was identified.

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BACKGROUND: Only 25% of IVF transfer cycles lead to a clinical pregnancy, calling for continued technical progress but also more in depth analysis of patients' individual characteristics. The interleukin-1 (IL-1) system and matrix metalloproteinases (MMPs) are strongly implicated in embryo implantation. The genes coding for IL-1Ra (gene symbol IL-1RN), IL-1beta, MMP2 and MMP9 bear functional polymorphisms. We analysed the maternal genetic profile at these polymorphic sites in IVF patients, to determine possible correlations with IVF outcome. METHODS: One hundred and sixty women undergoing an IVF cycle were enrolled and a buccal smear was obtained. The presence of IL-1RN variable number of tandem repeats and IL-1B + 3953, MMP2-1306 and MMP9-1562 single nucleotide substitutions were determined. Patients were divided into pregnancy failures (119), biochemical pregnancies (8) and clinical pregnancies (33). RESULTS: There was a 40% decrease in IL-1RN*2 allele frequency (P = 0.024) and a 45% decrease in IL-1RN*2 carrier status in the clinical pregnancy group as compared to the pregnancy failure group (P = 0.017). This decrease was still statistically significant after a multivariate logistic regression analysis. The likelihood of a clinical pregnancy was decreased accordingly in IL-1RN*2 carriers: odds ratio = 0.349, 95% confidence interval = 0.2-0.8, P = 0.017. The IL-1B, MMP2 and MMP9 polymorphisms showed no correlation with IVF outcome. CONCLUSIONS: IL-1RN*2 allele carriage is associated with a poor prognosis of achieving a pregnancy after IVF.

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Aminoglycoside antibiotics are ototoxic, inducing irreversible sensorineural hearing loss mediated by oxidative and excitotoxic stresses. The NF-kappaB pathway is involved in the response to aminoglycoside damage in the cochlea. However, the molecular mechanisms of this ototoxicity remain unclear. We investigated the expression of PKCzeta, a key regulator of NF-kappaB activation, in response to aminoglycoside treatment. Amikacin induced PKCzeta cleavage and nuclear translocation. These events were concomitant with chromatin condensation and paralleled the decrease in NF-kappaB (p65) levels in the nucleus. Amikacin also induced the nuclear translocation of apoptotic inducing factor (AIF). Prior treatment with aspirin prevented PKCzeta cleavage and nuclear translocation. Thus, aspirin counteracts the early effects of amikacin, thereby protecting hair cells and spiral ganglion neurons. These results demonstrate that PKCzeta acts as sentinel connecting specific survival pathways to mediate cellular responses to amikacin ototoxicity.

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Este trabalho procura traçar um painel da situação do acervo bibliográfico, em termos de periódicos especializados em ecologia, de algumas das principais universidades brasileiras. A pesquisa baseou-se na escolha de um tópico básico o qual, vem recebendo grande ênfase na literatura internacional ao longo dos últimos anos: a produção secundária. Todos os meios de procura disponíveis, sejam eles convencionais Symbol>¾ arquivos, fichários, microfilmes Symbol>¾ , ou aqueles recentemente implantados, tais como os bancos de dados em CD ROM, foram empregados. Das dez bibliotecas universitárias selecionadas, apenas a Universidade de São Paulo (USP) pode oferecer um acervo que cobre satisfatoriamente a maioria das referências selecionadas. Um segundo grupo de universidades, composto pela Universidade de Campinas (UNICAMP), Universidade Estadual Paulista (UNESP) e Universidade Federal do Rio de Janeiro (UFRJ) apresentou percentuais de cobertura variando entre 40 e 60%. A maioria das outras bibliotecas universitárias, no entanto, manteve-se em um patamar comparável ao da Universidade Federal de Minas Gerais (UFMG) ou Universidade de Brasília (UNB), ou seja, com percentuais de cobertura inferiores a 40%. Destaca-se ainda, que muitas das universidades selecionadas, mesmo possuindo cursos de pós-graduação em ecologia, exibiram, em seu conjunto, dados que demonstram inequivocamente a pobreza de seu, acervos na área de ecologia

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O HTML Symbol>- Hypertext Markup Language Symbol>- é uma linguagem de marcação*, inicialmente concebida como uma solução para a publicação de documentos científicos em meios eletrônicos, que ganhou popularidade e se tornou padrão para a Internet. Diversos tipos de aplicações, como navegadores, editores, programas de e-mail, bancos de dados etc., tornam possível atualmente o uso intensivo do HTML. Ao longo dos anos, recursos têm sido adicionados ao HTML para que ele possa atender às expectativas de usuários e sistemas computadorizados, aumentando sua complexidade. Estima-se que a versão 4.0 do HTML possua aproximadamente cem diferentes marcações fixas (conhecidas como tags), sem contar aquelas específicas para cada tipo de navegador da Internet. É comum se encontrarem páginas HTML que possuem mais marcações do que conteúdo. Uma possível solução para novas demandas nessa área é a utilização do Extended Markup Language (XML), uma linguagem de marcação que pode introduzir novas possibilidades e trazer melhor integração entre dados e usuários. Este artigo se propõe a abordar, de forma introdutória, o XML, sua utilização na Internet, alguns conceitos complementares necessários ao entendimento do assunto em apresentar vantagens no uso do XML, em relação ao HTML. Além disso, pretende apresentar o assunto como um campo fértil para discussões, proposições e estudo por profissionais da ciência da informação.

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O objetivo deste trabalho foi estudar a interferência interespecífica entre duas espécies de Amaranthus -- A. viridis e A. hybridus Symbol>¾, esta última com dois biótipos distintos (verde e roxo); ambas ocorriam associadas em dois locais. Nas populações de cada local foram feitos ensaios de substituição independentes, em vasos, nos quais observou-se que as populações que germinam mais prontamente são as que vencem em competição, ou seja, se estabelecem e produzem maior número de sementes. Houve tendência de A. hybridus (tipo verde) dominar tanto A. hybridus (tipo roxo) como A. viridis, e de A. hybridus (tipo roxo) dominar A. viridis. Em cultivo misto, houve casos em que as espécies estavam competindo pelos mesmos recursos, ou explorando recursos diferentes do ambiente, ou mesmo com antagonismo mútuo.

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This research consisted of five laboratory experiments designed to address the following two objectives in an integrated analysis: (1) To discriminate between the symbol Stop Ahead warning sign and a small set of other signs (which included the word-legend Stop Ahead sign); and (2) To analyze sign detection, recognizability, and processing characteristics by drivers. A set of 16 signs was used in each of three experiments. A tachistoscope was used to display each sign image to a respondent for a brief interval in a controlled viewing experiment. The first experiment was designed to test detection of a sign in the driver's visual field; the second experiment was designed to test the driver's ability to recognize a given sign in the visual field; and the third experiment was designed to test the speed and accuracy of a driver's response to each sign as a command to perform a driving action. A fourth experiment tested the meanings drivers associated with an eight-sign subset of the 16 signs used in the first three experiments. A fifth experiment required all persons to select which (if any) signs they considered to be appropriate for use on two scale model county road intersections. The conclusions are that word-legend Stop Ahead signs are more effective driver communication devices than symbol stop-ahead signs; that it is helpful to drivers to have a word plate supplementing the symbol sign if a symbol sign is used; and that the guidance in the Manual on Uniform Traffic Control Devices on the placement of advance warning signs should not supplant engineering judgment in providing proper sign communication at an intersection.

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Com o objetivo de estudar a absorção de macronutrientes (N, P, K, Ca, Mg e S) em explantes de bananeira cv. Prata Anã, foram utilizados explantes de plantas estabelecidas in vitro, inoculados em meio básico de Murashige & Skoog (1962) contendo sacarose (30 g/L), e BAP (3,5 mg/L) com sete tratamentos, representados pelos períodos de 0, 10, 20, 30, 40, 50 e 60 dias de cultivo e três repetições. As quantidades de macronutrientes totais absorvidas pelos explantes seguiram a ordem: K > N > Ca > ou = P > Mg Symbol>@ S. O P foi o nutriente absorvido mais rapidamente pelos explantes, com 75% extraído do meio de cultivo nos primeiros 30 dias, cessando sua absorção aos 50 dias, restando ainda 9% no meio de cultivo. A absorção do S cessou também aos 50 dias, quando 66% deste nutriente ainda permanecia no meio de cultivo. Este resultado sugere haver uma relação, quanto à absorção, entre esses dois nutrientes. As maiores taxas de absorção de todos os nutrientes foram verificadas nos primeiros 20 dias. O rizoma, o pseudocaule e as folhas, se diferenciaram quanto à concentração e extração ou acúmulo de nutrientes.

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IB1/JIP-1 is a scaffold protein that regulates the c-Jun NH(2)-terminal kinase (JNK) signaling pathway, which is activated by environmental stresses and/or by treatment with proinflammatory cytokines including IL-1beta and TNF-alpha. The JNKs play an essential role in many biological processes, including the maturation and differentiation of immune cells and the apoptosis of cell targets of the immune system. IB1 is expressed predominantly in brain and pancreatic beta-cells where it protects cells from proapoptotic programs. Recently, a mutation in the amino-terminus of IB1 was associated with diabetes. A novel isoform, IB2, was cloned and characterized. Overall, both IB1 and IB2 proteins share a very similar organization, with a JNK-binding domain, a Src homology 3 domain, a phosphotyrosine-interacting domain, and polyacidic and polyproline stretches located at similar positions. The IB2 gene (HGMW-approved symbol MAPK8IP2) maps to human chromosome 22q13 and contains 10 coding exons. Northern and RT-PCR analyses indicate that IB2 is expressed in brain and in pancreatic cells, including insulin-secreting cells. IB2 interacts with both JNK and the JNK-kinase MKK7. In addition, ectopic expression of the JNK-binding domain of IB2 decreases IL-1beta-induced pancreatic beta-cell death. These data establish IB2 as a novel scaffold protein that regulates the JNK signaling pathway in brain and pancreatic beta-cells and indicate that IB2 represents a novel candidate gene for diabetes.