968 resultados para Guarnieri, Camargo, 1907-1993, Sonatinas n.3 e n.6 para piano


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The paper describes a model for a 6-phase induction motor driven by an inverter operating in a 6-pulse (square wave) mode. The model is implemented and performance, in terms of torque, current, efficiency and pulsating torque, compared to the performance of a 3-phase motor (both sine and 6-pulse supplied). The models are verified experimentally, in particular the efficiency performance, and it is illustrated that the improvement in inverter efficiency when in 6-pulse operating mode may improve the performance of the overall system. © 2005 IEEE.

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从鲤鱼3个亚种(Cyprinus carpio carpio,Cyprinus carpio haematopterus和Cyprinus carpiorubrofuscus)中选出具代表性的品系共10个,运用PCR方法,扩增出2.4 kb的mtDNA ND5/6区段.共用9种限制性内切酶进行酶切分析,结果表明,每个亚种拥有一种单倍型,有4种限制性内切酶(Dde I,Hae III,Taq I和Mbo I)酶切后产生了能将3个亚种区分开来的诊断性限制性酶切位点.可利用其作为鉴定3个亚种的遗传标记和遗传育种

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A facile and efficient one-pot synthesis of substituted cyclophosphamidic chlorides and their analogues has been developed from readily available enaminones, 2-arylamino-3-acetyl-5,6-dihydro4H-pyrans.

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The crystal structure of the title compound, C12H10ClF3O3, was determined in order to establish the configuration of the C double bond. The compound was found to be the Z isomer. The crystal structure is dominated by Cl center dot center dot center dot O halogen bonds [Cl center dot center dot center dot O = 3.111 (3) angstrom], as well as C-H center dot center dot center dot O and C-H center dot center dot center dot F hydrogen-bonding interactions, that connect neighboring molecules into a three-dimensional supramolecular network.

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A facile and efficient one-pot synthesis of highly substituted pyridin-2(IH)-ones was developed via Vilsmeier-Haack reactions of readily available enaminones, 2-arylamino-3-acetyl-5,6-dihydro-4H-pyrans, and a mechanism involving sequential ring-opening, haloformylation, and intramolecular nucleophilic cyclization reactions is proposed.

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To understand how a signaling molecule's activities are regulated, we need insight into the processes controlling the dynamic balance between its synthesis and degradation. For the Ins(1,3,4,5,6)P5 signal, this information is woefully inadequate. For example, the only known cytosolic enzyme with the capacity to degrade Ins(1,3,4,5,6)P5 is the tumour-suppressor PTEN [J.J. Caffrey, T. Darden, M.R. Wenk, S.B. Shears, FEBS Lett. 499 (2001) 6 ], but the biological relevance has been questioned by others [E.A. Orchiston, D. Bennett, N.R. Leslie, R.G. Clarke, L. Winward, C.P. Downes, S.T. Safrany, J. Biol. Chem. 279 (2004) 1116 ]. The current study emphasizes the role of physiological levels of PTEN in Ins(1,3,4,5,6)P5 homeostasis. We employed two cell models. First, we used a human U87MG glioblastoma PTEN-null cell line that hosts an ecdysone-inducible PTEN expression system. Second, the human H1299 bronchial cell line, in which PTEN is hypomorphic due to promoter methylation, has been stably transfected with physiologically relevant levels of PTEN. In both models, a novel consequence of PTEN expression was to increase Ins(1,3,4,5,6)P5 pool size by 30-40% (p<0.01); this response was wortmannin-insensitive and, therefore, independent of the PtdIns 3-kinase pathway. In U87MG cells, induction of the G129R catalytically inactive PTEN mutant did not affect Ins(1,3,4,5,6)P(5) levels. PTEN induction did not alter the expression of enzymes participating in Ins(1,3,4,5,6)P5 synthesis. Another effect of PTEN expression in U87MG cells was to decrease InsP6 levels by 13% (p<0.02). The InsP6-phosphatase, MIPP, may be responsible for the latter effect; we show that recombinant human MIPP dephosphorylates InsP6 to D/L-Ins(1,2,4,5,6)P5, levels of which increased 60% (p<0.05) following PTEN expression in U87MG cells. Overall, our data add higher inositol phosphates to the list of important cellular regulators [Y. Huang, R.P. Wernyj, D.D. Norton, P. Precht, M.C. Seminario, R.L. Wange, Oncogene, 24 (2005) 3819 ] the levels of which are modulated by expression of the highly pleiotropic PTEN protein.

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The X-ray crystal structures of two lamotrigine derivatives (I) 3,5-diamino-6-(2-chlorophenyl)-1,2,4-triazine, C9H8ClN5, (465BL) as a hydrate, and (II) 3,5-diamino-6-(3,6-dichlorophenyl)-1,2,4-triazine, C9H7Cl2N5, (469BR) as a methanol solvate, have been carried out at liquid nitrogen temperature and room temperature, respectively. A detailed comparison of the two structures is given. Both are centrosymmetric with (I) in the orthorhombic space group Pbca, a = 12.2507(3), b = 15.7160(6), c = 21.71496(9) angstrom, Z = 16, and (II) in the monoclinic space group C2/c, a = 38.553(3), b = 4.9586(2), c = 14.546(2) angstrom, beta = 111.59(1)degrees, Z = 8. Final R indices [I > 2sigma(I)] for (I) are R1 = 0.0670, wR2 = 0.1515 and for (II) R1 = 0.0434, wR2 = 0.1185. Structure (I) has water of crystallization in the lattice and (II) includes a solvated CH3OH. Structure (I) is characterized by having two crystallographically independent molecules, A and B, of 465BL, per asymmetric unit. Molecule B has a very unusual feature in that the 2-chlorophenyl ring is statistically disordered, occupying site (1) in 87.5% of the structure and site (2) in 12.5% of the structure. Sites (1) and (2) are related by an exact 180 degrees pivot of the phenyl ring about the ring linkage bond. The presence of two independent molecules per asymmetric unit provides an ideal opportunity for the conformational flexibility of the molecule 465BL to be studied. Structure (I) also includes a further unusual feature in that the lattice contains one fully occupied water molecule and an additional solvated water which is only 33% occupied.

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The X-ray crystal structures of two lamotrigine derivatives (I) 2-methyl, 3-amino, 5-imino-6-(2, 3-dichlorophenyl)-1,2,4-triazine, C10H9Cl2N5, as the hemi hydrate and (II) 2-methyl,3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazine, C10H10Cl2N5, as the isethionate-water solvate, have been carried out at liquid nitrogen temperature. A detailed comparison of the two structures is given. Both are monoclinic and centrosymmetric, with (I) in space group C2/c, and (II) in space group P2(1)/n. For (I) the unit cell dimensions are a = 19.5466(10), b = 7.5483(4), c = 15.7861(8) angstrom, beta = 91.458(3)degrees, volume = 2328.4(2) angstrom(3), Z = 8, density = 1.590 Mg/m(3); for (II). For (II) the unit cell dimensions are a = 6.0566(2), b = 11.0084(4) c = 23.9973(9) angstrom, beta = 92.587(3)degrees, volume = 1598.35(10) angstrom(3), Z = 4, density = 1.597 Mg/m(3). For (I) final R indices [I > 2sigma(I)] are R1 = 0.0356, wR2 = 0.0782 and R indices (all data) are R1 = 0.0424, wR2 = 0.0817. For (II) final R indices [I > 2sigma(I)] are R1 = 0.0380, wR2 = 0.0871 and R indices (all data) R1 = 0.0558, wR2 = 0.0949. Both structures have a molecule of water of crystallization and (II) also includes a solvated CH3SO3. Comparisons are made between the two structures. Structure (I) is very unusual in having a = NH group at position C5' on the triazine ring. No other examples of this particular substitution, which is usually -NH2, have been reported.

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RESUMO: Os glicoconjugados que decoram a superfície celular e os lípidos e proteínas secretados ocupam o ponto de encontro onde normalmente ocorrem interacções críticas homólogas (hospedeiro-hospedeiro) e heterólogas (hospedeiro-patogénio). Apesar de ser largamente aceite que os glicanos são parte integrante do processo de imunidade, continua a não ser claro qual o papel que os glicanos, em toda a sua diversidade, tomam no quadro geral da imunidade. Os glicanos, que são frequentemente terminados por resíduos de ácido siálico, podem ser alterados por factores externos, tais como patogénios, ou por acontecimentos fisiológicos celulares específicos. Normalmente em posição terminal, as glico-estruturas que contêm ácido siálico assumem um papel fundamental numa quantidade substancial de receptores imunes envolvidos na adesividade e tráfico celular, tal como as Selectinas e as Siglecs, das quais se sabe apresentarem uma relevante função imune. À altura do início desta tese, era sabido que os ácidos siálicos expressos à superfície das células poderiam modular mecanismos importantes nas respostas imunes adaptativas. Considerando a posição de charneira que as células dendríticas (DCs) ocupam na transição da resposta imune inata para a adaptativa, antecipámos que os ácidos siálicos poderiam também modular mecanismos relevantes nas DCs humanas. As DCs têm uma função muito relevante na verificação e captura antigénica, migração para os gânglios linfáticos e apresentação antigénica aos linfócitos, uma sequência de funções que conduz, em ultima instância, à indução da resposta inata adaptativa. Considerando estas premissas, a nossa hipótese principal foi que os ácidos siálicos podem influenciar funções relevantes das DCs, tais como captura de antigénios, maturação, migração para os gânglios linfáticos e apresentação antigénica às células Para testar esta hipótese, dividimos o trabalho em quatro partes: 1) Analisámos os glicanos sialilados de superfície, expressos durante a diferenciação de monócitos humanos em DCs (moDCs). Os nossos dados mostraram que a expressão dos glicanos com ligações em O (O-glicanos) e sialilados em α2,3, assim como glicanos com ligações em N (N-glicanos) sialilados em α2,6 e α2,3 aumentou durante o processo de diferenciação das moDCs. Contribuindo para esta nova configuração glicosídica, três sialiltransferases (STs) poderão estar envolvidas: a ST6Gal-1 correlaciona-se com a expressão aumentada de N-glicanos sialilados em α2,6; a ST3Gal-1 contribui para a sialilação em α2,3 de O-glicanos, em especial de antigénios T; e a ST3Gal-4 poderá ser responsável pelo aumento de N-glicanos sialilados em α2,3. Após estímulo e consequente maturação das moDCs, ambos os níveis de expressão génica de ST6Gal-1 e ST3Gal-4 são negativamente modificados sendo, também, que a expressão de ST3Gal-1 varia consoante o estímulo. 2) Estudámos posteriormente as consequências da modulação dos ácidos siálicos de superfície nas funções das DCs. Observámos que a remoção dos ácidos siálicos de superfície diminui significativamente a capacidade de macropinocitose e endocitose mediada por receptores nas moDCs. Em contrapartida, o tratamento com sialidase aumentou significativamente a capacidade das moDCs para fagocitar Escherichia coli. Determinou-se também que este mecanismo requer a existência de ácido siálico presente nas E. coli indicando um mecanismo de interacção hospedeiro-patogénio dependente de ácido siálico em ambas as partes envolvidas. As moDCs tratadas com sialidase também apresentam um nível superior de expressão de moléculas de MHC e moléculas co-estimulatórias, sugerindo um fenótipo celular mais maduro. Recorrendo ao modelo de ratinho, utilizaram-se DCs derivadas de células da medula (BMDCs) de ratinhos deficientes em ST3Gal-1 e ST6Gal-1. Estes ensaios revelaram que quer a endocitose quer a maturação são influenciadas por modificações 37 nos glicanos sialilados em α2,3 ou α2,6. A detecção e quantificação de proteínas Nglicosiladas e sialiladas em α2,6 apontou para um potencial envolvimento de integrinas β2 nestes mecanismos. 3) O efeito da sialilação em α2,6 na migração das DCs para os gânglios linfáticos foi também analisado. Observámos que BMDCs deficientes para ST6Gal-1 apresentam uma redução de cerca de 50% nos níveis de migração das DCs para os gânglios linfáticos, tal como aferido em ensaios de inflamação in situ e estudos de transferência adoptiva de células. Uma redução dos níveis deste tipo de migração foi também observada quando BMDCs nativas foram transferidas para ratinhos receptores deficientes em ST6Gal-1. São, contudo, necessários mais ensaios de forma a identificar as moléculas envolvidas neste processo. 4) Por último, analisámos o impacto da sialilação na estimulação antigénica das DCs às células T. Assim, concluiu-se que moDCs tratadas com sialidase apresentam um nível de expressão superior de IL-12, TNF-ɑ, IL-6 e IL-10, e activação do factor de transcrição nuclear kappa B (NF-κB). As DCs tratadas com sialidase induziram uma maior proliferação nas células T, com expressão correspondente de interferão-γ. Este dado sugere que a remoção de ácidos siálicos de superfície contribui para o desenvolvimento de uma resposta pro-inflamatória do tipo 1 por células T auxiliares (resposta Th1). Considerando estes dados no seu todo, concluímos que o ácido siálico tem um papel marcante nas funções imunes das DCs. Alterações à concentração de ácido siálico à superfície das células podem alterar a endocitose/fagocitose, maturação, migração para os tecidos e gânglios linfáticos e capacidade estimulatória para com as células T. Complementando estes dados, as ligações glicosídicas de ácidos siálicos criados por ST6Gal-1 e ST3Gal-1 são funcionalmente relevantes. A modulação programada da sialilação do glicocálice, mediada por sialidases individuais ou sialiltransferases é uma possibilidade aceitável para a melhoria da fagocitose por DCs e da sua potência imunológica. Este facto tem um significado particular para imunoterapias baseadas em DCs, podendo provar-se decisivo para a sua eficiência e aplicabilidade num futuro muito próximo.-------------------------------ABSTRACT: Glycans decorating cell surface and secreted proteins and lipids occupy the junction where critical host–host and host-pathogen interactions occur. In spite of the wide acceptance that glycans are centrally implicated in immunity, exactly how glycans and their variety and variability contribute to the overall immune response remains poorly defined. Glycans, frequently terminated by sialic acid residues, may be modified by external factors such as pathogens or upon specific physiological cellular events. The terminal, privileged positions of sialic acid-modified structures makes them key, fundamental determinants for a number of immune receptors with known involvement in cellular adhesiveness and cell trafficking, such as Selectins and Siglecs, with known relevant immune functions. At the time this thesis was initiated, it was established that sialic acids expressed at cell surface could modulate important mechanisms of the adaptive immune responses. Given the key role of dendritic cells (DCs) in the transition from innate to the adaptive immune responses, we anticipated that sialic acids could also modulate important mechanisms of human DCs. DCs have a relevant role in antigen screening and uptake, migration to lymph nodes and antigen presentation to lymphocytes, ultimately triggering the adaptive immune response. Therefore, our primary hypothesis was that sialic acids may modulate DC functions, such as antigen uptake, maturation, homing to lymph nodes and antigen presentation to T cells. To test this hypothesis, we divided our work in four parts. 1) Surface sialylated glycans expressed during differentiation from human monocytes to DCs (moDCs) were analyzed. Our data showed that α2,3-sialylated O-glycans and α2,6- and α2,3-sialylated N-glycans expression increased during moDC differentiation. Three main sialyltransferases (STs) are committed with this new glycan configuration: ST6Gal- 1 correlates with the increased expression of α2,6-sialylated N-glycans; ST3Gal-1 32 contributes for the α2,3-sialylation of O-glycans, especially T antigens; and ST3Gal-4 may contribute for the increased α2,3-sialylated N-glycans. Upon moDC maturation, ST6Gal-1 and ST3Gal-4 are downregulated and ST3Gal-1 is altered in a stimulus dependent manner. 2) We subsequently analyzed the consequences of the modulation of cell surface sialic acids in DC functions. We observed that removing surface sialic acid by sialidase significantly decreased the capacity of moDCs to micropinocytose and receptormediated endocytose. In contrast, treatment with a sialidase significantly improved the capacity of moDCs to phagocytose Escherichia coli. The improved phagocytosis mechanism required E. coli sialic acids, indicating a mechanism of host–pathogen interaction dependent on sialic acid moieties. Sialidase-treated moDCs have increased expression of MHC and co-stimulatory molecules, suggesting a more mature phenotype. Experiments using mouse bone marrow-derived DCs (BMDCs) from ST3Gal-1-/- and ST6Gal-1-/- strains indicated that endocytosis and maturation are influenced by changes in either α2,3 or α2,6-sialylated glycans. The analysis of α2,6-sialylated, N-glycosylated proteins, strongly suggested the potential involvement of β2 integrins, underlying these mechanisms. 3) The effect of α2,6-sialylation in DC homing to lymph nodes was also analyzed. We observed that BMDCs deficient for ST6Gal-1 have an almost 50% reduction in DC homing, as assayed by in situ inflammation and adoptive transfer studies. A reduction in DC homing was also observed when wild type BMDCs were transferred into ST6Gal-1-/- recipient mice. Further investigations are necessary to identify the molecules involved in this process. 4) Finally, we also analyzed the impact of sialylation on DCs ability to prime T cells. Sialidase-treated moDCs show increased gene expression of IL-12, TNF-α, IL-6 and IL- 10 cytokines, and activation of the transcription factor nuclear factor-κB. Sialidase33 treated DCs induced a higher proliferative response of T cells with concomitant higher expression of interferon-γ, suggesting that the clearance of cell surface sialic acids contributes to the development of a T helper type 1 proinflammatory response. Together, our data strongly support sialic acid’s relevance in DC immune functions. Alterations of cell surface sialic acid content can alter the endocytosis/phagocytosis, maturation, migration/homing and the ability for T cell priming in human DCs. Moreover, sialic acid linkages created by ST6Gal-1 and ST3Gal-1 are functionally relevant. The engineering of cell surface sialylation, mediated by individual sialidases or sialyltransferases is a likely possibility to fine tune DC phagocytosis and immunological potency, with particular significance to DC-based therapies.

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Survey map of the Second Welland Canal created by the Welland Canal Company showing the canal along Chippewa Creek in Thorold Township. Identified structures and features associated with the Canal include the towing path, the back ditch, and the waterway itself. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include roads (ex. Road to Welland), Chippewa Creek, and a pond. Properties and property owners of note are: Lots 214, 215, 216 and 222, and Heaslip.

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Tesis (Maestría en Ciencias con Especialidad en Qúimica Orgánica) UANL

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Lecture 6: Where are all the links taking us: Web Science Contains Powerpoint Lecture slides and Hypertext Research Papers: The Literati (The Cyberspace and critical theory website) (Eastgate website); Pervasive Hypertext at Southampton and at Aarhus; Adaptive Hypertext - The Next Big Thing: (De Bra & Chepegin, 2004); Web Science: Creating a Science of the Web (Berners-Lee, Hall, Hendler, Shadbolt & Weitzner, 2006).

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Este libro completa una serie temática acerca de los juegos en la educación básica que abarca de los 3 a los 14 años de edad. Los juegos se clasifican por áreas, lo que permite que se vaya más allá de la aplicación al desarrollo motor del niño en beneficio de una dimensión mucho más globalizadora. Recoge 390 propuestas, en cada una de las cuales se indica la edad a la que va dirigida, el material, la organización, los objetivos, las áreas o ámbitos de experiencia, el desarrollo, las reglas y posibles variantes.