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Atitude dos professores do 1º e 2º ciclos do ensino básico face à inclusão de alunos com dislexia no ensino regular

Lopes, Maria Cristina Santos
Fonte: Repositório Científico Lusófona Publicador: Repositório Científico Lusófona
Tipo: Dissertação de Mestrado
Português
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Através dos tempos, a legislação que disciplina a Inclusão de alunos com deficiência nas escolas regulares, sofreu transformações que conduziram a uma crescente responsabilização dessas mesmas escolas, pela Inclusão destes alunos numa perspectiva de "Escola Para Todos". Desta forma, este trabalho pretende apresentar um estudo sobre a inclusão de Disléxicos. O seu objectivo principal foi conhecer as atitudes dos professores, perante o factor inclusão, de alunos com Dislexia. Tendo em conta os objectivos que regulam este estudo e fundamentam este trabalho, a selecção metodológica deliberada tem um carácter descritivo, no quadro do paradigma quantitativo. (Doyle, 1978), após uma recolha de dados por questionário triangulando-o com o paradigma qualitativo, uma vez que estamos convictos de que ― as técnicas triangulares nas Ciências Sociais visam explicar de maneira mais completa, a riqueza e complexidade do comportamento humano estudando-o desde mais que um ponto de vista‖ (Cohen e Manion, 1990:331). A metodologia de triangulação com predominância das técnicas quantitativas foi aplicada a uma amostra constituída por docentes do 1º, 2º Ciclos, do concelho de Baião. Utilizamos como instrumento para a recolha de dados...

Formation of the active site of ribulose-1,5-bisphosphate carboxylase/oxygenase by a disorder-order transition from the unactivated to the activated form.

Schreuder, H A; Knight, S; Curmi, P M; Andersson, I; Cascio, D; Brändén, C I; Eisenberg, D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/11/1993 Português
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Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) catalyzes the key first step in photosynthetic CO2 fixation, the reaction that incorporates CO2 into sugar. In this study, refined crystal structures of unactivated tobacco RuBisCO and activated RuBisCO from spinach and tobacco, in complex with the reaction-intermediate analog 2-carboxyarabinitol 1,5-bisphosphate (CABP), are compared. Both plant enzymes are hexadecameric complexes of eight large and eight small subunits with a total relative molecular mass of approximately 550,000. The comparison of activated and unactivated forms of RuBisCO provides insight into the dynamics of action of this enzyme. The catalytic site, which is open to the solvent in the unactivated enzyme, becomes shielded in the activated CABP complex. This shielding is accomplished by a 12-A movement of the active-site "loop 6" (residues 331-338) and a disorder-order transition of three loops near the active-site entrance, the N terminus, the C terminus, and a loop comprising residues 64-68. All these residues belong to the catalytic large subunit. Domain rotations of about 2 degrees are observed, also tightening the active-site cleft. These observations provide an explanation for the extremely tight binding (Kd < or = 10(-11) M) of the CABP molecule. A striking correlation exists between crystallographic temperature factors in the activated enzyme and the magnitude of the atomic movement upon activation.

Enhancement of antibiotic susceptibility and suppression of Mycobacterium avium complex growth by poloxamer 331.

Hunter, R L; Jagannath, C; Tinkley, A; Behling, C A; Nolte, F
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1995 Português
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The resistance of Mycobacterium avium complex (MAC) to antibiotics is thought to be enhanced by its outer glycolipid layer, which protects the organisms from antibiotics and host defense mechanisms. We hypothesized that surfactants which disrupt the lipid barrier might be of therapeutic value. We evaluated the ability of 10 poloxamer surfactants to inhibit the growth of MAC organisms and to potentiate antimycobacterial drug activity in broth culture using a radiometric assay. Very large, small, or hydrophilic poloxamers had little or no effect. However, certain hydrophobic poloxamers, especially P331, retarded the growth of most isolates of MAC and produced a synergistic effect with rifampin. The MIC of rifampin required to inhibit the growth of MAC was reduced from a mean of 14.6 micrograms/ml (range, 4 to > 32 micrograms/ml) to 1.4 micrograms/ml (range, < 1.125 to 4 micrograms/ml) by 1.0 mg of P331 per ml (P < 0.01). Enhancement of antibiotic susceptibility was observed with concentrations of poloxamer as low as 10 micrograms/ml. These studies suggest that P331 might be useful in increasing the effectiveness of antibiotic therapy of MAC infections.

Functional contribution of cysteine residues to the human immunodeficiency virus type 1 envelope.

Tschachler, E; Buchow, H; Gallo, R C; Reitz, M S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1990 Português
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Although the envelope gene of human immunodeficiency virus type 1 shows considerable strain variability, cysteine residues of the envelope protein are strongly conserved, suggesting that they are important to the envelope structure. We constructed and analyzed mutants of a biologically active molecular clone of human immunodeficiency virus type 1 in which different cysteines were replaced by other amino acids in order to determine their functional importance. Substitution of cysteines 296 and 331, on either side of a region recognized by type-specific neutralizing antibodies, or on either side (residues 418 and 445) of a region important for CD4 binding, resulted in noninfectious mutants. These mutants were blocked early in the viral life cycle. Their gp160 envelope precursor polypeptides were poorly cleaved, and CD4 binding was also strongly impaired. Similar substitutions in the first variable region (residue 131) or between the first and second variable regions (residue 196) also gave noninfectious mutant virus, but here the block was late in the virus life cycle; these mutants were defective for syncytium formation. Substitution of cys386, between the neutralization and CD4 binding regions, resulted in a virus which retained infectivity but which spread much more slowly than the wild type. As with the cys131 and cys196 mutants...

(1H-1,2,3-Benzotriazol-1-yl)methyl 2,2-dimethyl­propano­ate

Xu, Sen; Shen, Yingzhong
Fonte: International Union of Crystallography Publicador: International Union of Crystallography
Tipo: Artigo de Revista Científica
Publicado em 14/03/2012 Português
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In the title compound, C12H15N3O2, the dihedral angle between the mean planes of the benzene and triazole rings is 0.331 (53) °. The side chain of the pivalate unit forms a dihedral angle of 69.04 (12)° with the benzotriazole unit. The ester group and two methyl groups of the pivalate unit are disordered with an occupancy ratio of 0.731 (3):0.269 (3). In the crystal, weak π–π stacking inter­actions are observed between inversion-related benzene rings [centroid–centroid distance = 3.9040 (1) Å].

Identification and Enhancement of HLA-A2.1-Restricted CTL Epitopes in a New Human Cancer Antigen-POTE

Huang, Yi-Hsiang; Terabe, Masaki; Pendleton, C. David; Stewart Khursigara, Deborah; Bera, Tapan K.; Pastan, Ira; Berzofsky, Jay A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 04/06/2013 Português
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Identification of CD8+ T cell epitopes that can induce T cells to kill tumor cells is a fundamental step for development of a peptide cancer vaccine. POTE protein is a newly identified cancer antigen that was found to be expressed in a wide variety of human cancers, including prostate, colon, lung, breast, ovary and pancreas. Here, we determined HLA-A2.1-restricted cytotoxic T lymphocyte (CTL) epitopes in the POTE protein, and also designed enhanced epitopes by amino acid (AA) substitutions. Five 9-mer peptides were first selected and their binding affinity to HLA-A2 molecules was measured by the T2 binding assay. POTE 272–280 and POTE 323–331 showed the strongest HLA-A2 binding affinity. AA substituted peptides POTE 252-9V (with valine at position 9), POTE 553-1Y (with tyrosine at position 1) and POTE 323-3F (with phenylalanine at position 3) conferred higher affinity for HLA-A2, and induced CTL responses cross-reactive with wild type antigens. While POTE 252-9V was the strongest in this respect, POTE 323-3F had the greatest increase in immunogenicity compared to wild type. Importantly, two modified epitopes (POTE-553-1Y and POTE-323-3F) induced CTLs that killed NCI-H522, a POTE-expressing HLA-A2+ human non-small cell lung cancer cell line...

Fast Growing, Healthy and Resident Green Turtles (Chelonia mydas) at Two Neritic Sites in the Central and Northern Coast of Peru: Implications for Conservation

Velez-Zuazo, Ximena; Quiñones, Javier; Pacheco, Aldo S.; Klinge, Luciana; Paredes, Evelyn; Quispe, Sixto; Kelez, Shaleyla
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 19/11/2014 Português
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In order to enhance protection and conservation strategies for endangered green turtles (Chelonia mydas), the identification of neritic habitats where this species aggregates is mandatory. Herein, we present new information about the population parameters and residence time of two neritic aggregations from 2010 to 2013; one in an upwelling dominated site (Paracas ∼14°S) and the other in an ecotone zone from upwelling to warm equatorial conditions (El Ñuro ∼4°S) in the Southeast Pacific. We predicted proportionally more adult individuals would occur in the ecotone site; whereas in the site dominated by an upwelling juvenile individuals would predominate. At El Ñuro, the population was composed by (15.3%) of juveniles, (74.9%) sub-adults, and (9.8%) adults, with an adult sex ratio of 1.16 males per female. Times of residence in the area ranged between a minimum of 121 and a maximum of 1015 days (mean 331.1 days). At Paracas the population was composed by (72%) of juveniles and (28%) sub-adults, no adults were recorded, thus supporting the development habitat hypothesis stating that throughout the neritic distribution there are sites exclusively occupied by juveniles. Residence time ranged between a minimum of 65 days and a maximum of 680 days (mean 236.1). High growth rates and body condition index values were estimated suggesting healthy individuals at both study sites. The population traits recorded at both sites suggested that conditions found in Peruvian neritic waters may contribute to the recovery of South Pacific green turtles. However...

Solubilizacao de Fosfatos de Rocha pro Aspergillus Niger em Diferentes Tipos de Vinhaca.

NAHAS, E., ASSIS, L.C. de
Fonte: Pesquisa Agropecuaria Brasileira, Brasilia, v.27, n.2, p.325-331, fev.1992 Publicador: Pesquisa Agropecuaria Brasileira, Brasilia, v.27, n.2, p.325-331, fev.1992
Tipo: Artigo em periódico indexado (ALICE)
Português
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Aspergillus niger foi inoculado em frascos contendo vinhacas mistas de diferentes origens a fluorapatita como fonte de fosforo, ou alternativamente fosfatos de rocha com diferentes composicoes. O crescimento do fungo e a solubilizacao de fluorapatita nao diferiram quando foi usada vinhaca esterilizada ou nao. O teor de solidos totais e soluveis foi, pelo menos, duas vezes superior na vinhaça a 65:35 (caldo: melaco) que a 10:1(caldo: mel). Possivelmente, o maior teor de acucares totais - acarretando maior teor de acidez titulavel , ou o menor crescimento fungico, tenham propiciado maior acumulo de fosfato soluvel na vinhaca a 10:1 que na vinhaca a 65:35. Nao se constatou diferenca apreciavel entre os teores de fosfato soluvel residual quando se empregou concentracoes crescentes de fluorapatita. Fosfatos de rocha de diferentes origens e concentracoes de fosforo influiram na capacidade solubilizadora do fungo. Enquanto com o fosfato concentrado apatitico grosso obteve-se favorecimento ao maior acumulo de fosfato soluvel no meio de cultura (1,08 mg/ml), com o bitolato Patos de Minas obteve-se a maior solubilizacao, correspondendo a 72% do total de fosfato.; 1992

Lixiviação de glyphosate e imazapyr em solos com diferentes texturas e composição química. I. Método do bioensaio.

SOUZA, A. P. de; FERREIRA, F.A.; SILVA, A. A. da; RUIZ, H.A.; PRATES, H.T.
Fonte: Planta Daninha, Campinas, v. 18, n. 1, p. 5-16, 2000. Publicador: Planta Daninha, Campinas, v. 18, n. 1, p. 5-16, 2000.
Tipo: Artigo em periódico indexado (ALICE)
Português
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A mobilidade dos herbicidas no perfil do solo e influenciado por varios processos, tais como, retencao, transformacao e transporte. O conhecimento destes fenomenos e fundamental para a perfeita compreensao do destino de tais produtos no ambiente. Dentre as varias tecnicas utilizadas nesses estudos, o metodo do bioensaio apresenta-se como de otima representatividade e reprodutibilidade. Em razao dessas caracteristicas, associadas a poucas informacoes sobre a mobilidade de herbicidas nos solos sob condicoes tropicais, foi conduzido um bioensaio objetivando verificar o movimento vertical do glyphosate e do imazapyr, em colunas de solos de diferentes texturas e composicao quimica, utilizando-se o tomaterio (Lycopersicon esculentum Mill var. Santa Clara) como planta-teste. Os resultados desse estudo permitiram concluir que: a)o limite de deteccao do bioensaio para o glyphosate e para o imazapyr corresponde ao menor valor de I50, obtido na curva padrao, 331,52 e 5,4 ug L-1, respectivamente; b) as concentracoes do glyphosate biologicamente ativo nos lixiviados dos solos de Vicosa e de Sabara encontram-se abaixo dos limite de deteccao do bioensaio; b) o glyphosate apresentou, na coluna de 1 cm, mobilidade muito baixa nos solos estudados; d) a mobilidade do imazapyr...

Estudio comparativo del síndrome coronario agudo laboral y no laboral

Piné Cáceres, María Teresa
Fonte: Universidade de Múrcia Publicador: Universidade de Múrcia
Tipo: Tese de Doutorado Formato: application/pdf
Português
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Actualmente, las enfermedades cardiovasculares, dentro de las que incluimos el Síndrome Coronario Agudo (SCA), se encuentran entre las primeras causas de Incapacidad Temporal (IT). En España se registran cada año 23.000 bajas laborales por enfermedad cardiovascular, siendo la causa más frecuente de IT tras la lumbalgia y la depresión. El objetivo de este estudio es conocer si existen diferencias en la evolución de los pacientes que sufren SCA, dependiendo de si los procesos de IT son considerados accidente laboral o enfermedad común, tanto a nivel de la asistencia sanitaria que reciben los pacientes tratados por el Sistema Público de Salud o por una Mutua, el gasto por prestaciones económicas que generan los procesos de IT en ambas contingencias, la situación funcional final de los pacientes, y su reincorporación al mundo laboral. También analizamos el papel desempeñado por la Rehabilitación Cardíaca en este tipo de procesos. Para ello, hemos estudiado un total de 600 pacientes que iniciaron un proceso de IT tras sufrir SCA, 301 por contingencia común (CC) y 299 por contingencia profesional (CP), y hemos comparado variables demográficas (edad, sexo y Comunidad Autónoma), clínicas (hipertensión arterial, diabetes mellitus...

Violencia de los usuarios hacia el personal de enfermería : evaluación del riesgo laboral y análisis de las consecuencias psicológicas

Galián Muñoz, Inmaculada
Fonte: Universidade de Múrcia Publicador: Universidade de Múrcia
Tipo: Tese de Doutorado Formato: application/pdf
Português
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La presente tesis doctoral se centra en el estudio de la exposición a la violencia de los usuarios del personal de enfermería de los hospitales públicos de la Región de Murcia, ya que el riesgo de violencia laboral presenta una especial importancia en el ámbito sanitario, siendo el colectivo de enfermería uno de los más afectados tal y como se refleja en distintos estudios (Franz, Zeh, Schablon, Kuhnert y Nienhaus, 2010; Kling, Yassi, Smailes, Lovato y Koehoorn, 2009; Roche, Diers, Duffield y Catling-Paull, 2010; Shields y Wilkins, 2009). Los objetivos de este estudio son conocer la exposición a ma¬nifestaciones hostiles de los usuarios hacia los profesionales de enfer¬mería hospitalaria dependientes del Servicio Murciano de Salud (SMS) según variables sociodemográficas y laborales; profundizar en el análisis de la exposición a violencia en el servicio detectado en el capitulo dos como más expuesto (urgencias), valorando, igualmente, la exposición a conductas hostiles según variables sociodemográficas y laborales, e incluyendo la presencia de posibles consecuencias psicológicas, así como una comparativa con los resultados de la muestra total de profesionales de enfermería hospitalaria; y por último, estudiar la relación entre la exposición a violencia y el nivel de burnout...

Honesty After a Labor Relationship

Blanco, Mariana; Cárdenas, Juan Camilo
Fonte: Facultad de Economía Publicador: Facultad de Economía
Tipo: info:eu-repo/semantics/workingPaper; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em 20/10/2015 Português
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Al final de un experimento controlado, donde se contrataron asistentes de investigación para la codificación de noticias de los periódicos en línea durante un mes, el experimentador-empleador los invitó a lanzar un dado y reportar el resultado con el fin de pagar en efectivo una cantidad proporcional y lineal en el número reportado, de 1 a 6. Otro grupo (control) de estudiantes similares, fue invitado a realizar la misma tarea, pero sin tener relación laboral previa con el experimentador-empleador. Nuestro grupo de tratamiento mostró niveles promedio más altos de honestidad, ya que la distribución de los números reportados por estos fue menos sesgada a la derecha. Es decir, el grupo de relaciones de trabajo fue más propenso a reportar números que están más cerca de la distribución uniforme (honesta) que el grupo de control, y que otros estudios con este tipo de experimento. Se conjetura que la relación laboral del grupo de tratamiento indujo mayores niveles de honestidad entre los participantes. Una de las posibles razones es que la relación de trabajo creada para el grupo de estudiantes de tratamiento incluía una serie de choques que implicaba la posibilidad de desempleo involuntario, generando incentivos para que los estudiantes interpretaran la honestidad como un rasgo que podría ser valorado en el mercado de trabajo. Este artículo contribuye a la creciente literatura sobre la comprensión de los motivos de la honestidad y el engaño.; At the end of a controlled experiment where research assistants were hired for coding news from online newspapers...

Structural and functional analysis of the human Y-box binding protein (YB-1) gene promoter.

Makino, Y; Ohga, T; Toh, S; Koike, K; Okumura, K; Wada, M; Kuwano, M; Kohno, K
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/05/1996 Português
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We have isolated three overlapping genomic clones containing the 5'portion of the human YB-1 gene. These clones span approximately 25 kb of contiguous DNA containing 10 kb of 5' flanking sequence and 15 kb of the gene. The nucleotide sequence of the first exon and of 2000 upstream base pairs (bp) was determined. The first axon is unusually large and contains a 166 bp coding sequence and a 331 bp untranslated region. CpG sequences cover the 5'-end of the YB-1 gene including its first axon and intron as well as the upstream regions. The GC content around the first exon is approximately 70% and a CpG-free region was located in the untranslated sequence. The segment preceding the major transcription initiation site does not contain a TATA box, CCAAT box and the binding sequence for known transcription factors. A transient expression assay using the chloramphenicol acetyltransferase (CAT) gene showed that the sequence from +24 to +281 was critical for CAT expression. Fluorescence in situ hybridization demonstrated the chromosomal locus of YB-1 gene on chromosome 1p34. Polymerase chain reaction analysis on other genomic phage DNAs showed that several clones were derived from pseudogenes.

MicroRNAs miR-21a and miR-93 are down regulated in peripheral blood mononuclear cells (PBMCs) from patients with type 1 diabetes

Carrasco, Elena; Codner Dujovne, Ether; Pizarro, Carolina; Valencia, Elizabeth; Pérez Bravo, Francisco; Salas-Pérez, Francisca
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo de revista
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Artículo de publicación ISI; Introduction: It is well established that type 1 diabetes (T1D) is an autoimmune disease. Controversial data exists regarding the differential control of the immune system in T1D patients compared to unaffected individuals. MicroRNAs (miRNAs) are involved in the control of gene expression (by negative regulation of gene expression at post-transcriptional level, by mediating translational repression or degradation of the mRNA targets). Their potential role in T cell activation and autoimmunity is controversial. Aim: We investigated the expression profile of miR-21a and miR-93 in PMC samples of 20 T1D patients and 20 healthy controls by means of qPCR in different glucose concentrations (basal, 11 nM and 25 mM), and we analyzed the possible relationship of this expression pattern with autoimmunity. Results: MiR-21a was significantly underexpressed in T1D samples (media values expression 0.23 ± 0.05, p < 0.01) compared to controls (values less than 1 indicate a decrease in gene expression). When the PMCs were incubated with glucose 11 mM and 25 mM, miR-21a expression decreased in controls and increased in T1D samples (0.506 ± 0.05, p < 0.04). MiR-93 was underexpressed in T1D patients (0.331 ± 0.05...

A responsabilidade subsidiária da administração pública por obrigações trabalhistas devidas a terceirizados: uma análise da decisão do STF que declara a constitucionalidade do art. 71, § 1º, da lei Nº 8.666/93

Sousa, Débora de Carvalho
Fonte: Centro Universitário de Brasília Publicador: Centro Universitário de Brasília
Tipo: Trabalho de Conclusão de Curso
Português
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O presente trabalho teve como objetivo a análise da decisão proferida no julgamento da ADC 16 pelo Supremo Tribunal Federal (STF), a qual declarou a constitucionalidade do artigo 71, § 1º, da Lei 8.666/93, para assim verificar a responsabilidade do Estado frente a obrigações trabalhistas no âmbito da terceirização. Esse instituto tem como essência a descentralização das atividades. Por um lado a Lei n. 8.666/93, em seu artigo 71, § 1º, firmava a irresponsabilidade do órgão público. Por outro lado, o Tribunal Superior do Trabalho (TST) editou a Súmula 331 dispondo acerca da responsabilidade subsidiária. Com conteúdos opostos, a controvérsia da responsabilidade frente aos débitos trabalhistas surgira. O STF recebeu diversas reclamações contestando a aplicação da Súmula, levando à configuração da controvérsia jurídica acerca da constitucionalidade ou não desse dispositivo da Lei n. 8.666/93. No ano de 2010, foi proferida a decisão do Supremo, declarando ser de fato constitucional a norma objeto da Ação Declaratória de Constitucionalidade. No entanto, firmou-se o entendimento no sentido de que a irresponsabilidade do ente público, tratada na referida lei, não deve ser considerada absoluta. A ADC 16 assumiu um importante papel de afirmar a harmonia entre os órgãos judiciários e a superioridade do Supremo. A responsabilidade atribuída à Administração é subjetiva...

SU_L(2) X U_Y(1)-invariant description of the bilepton contribution to the WWV vertex in the minimal 331 model

Montano, J.; Tavares-Velasco, G.; Toscano, J. J.; Ramirez-Zavaleta, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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We study the one-loop sensitivity of the WWV (V=gamma, Z) vertex to the new massive gauge bosons predicted by the minimal SU_L(3) X U_X(1) model, which have unusual couplings to the standard model (SM) gauge bosons. A gauge-fixing procedure covariant under the SU_L(2) X U_Y(1) group was introduced for these new gauge bosons (dubbed bileptons) in order to generate gauge-invariant Green functions. The similarities between this procedure and the nonconventional quantization scheme of the background field method are discussed. It is found that, for relatively light bileptons, with a mass ranging from 2m_W to 6m_W, the radiative corrections to the form factors associated with the WWV vertex can be of the same order of magnitude than the SM one. In the case of heavier bileptons, their contribution is smaller by about one and two orders of magnitude than their SM counterpart.; Comment: Includes two new figures, two tables are removed, results and conclusion remain unchanged

spo(2|2)-Equivariant Quantizations on the Supercircle $S^{1|2}$

Mellouli, Najla; Nibirantiza, Aboubacar; Radoux, Fabian
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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We consider the space of differential operators $\mathcal{D}_{\lambda\mu}$ acting between $\lambda$- and $\mu$-densities defined on $S^{1|2}$ endowed with its standard contact structure. This contact structure allows one to define a filtration on $\mathcal{D}_{\lambda\mu}$ which is finer than the classical one, obtained by writting a differential operator in terms of the partial derivatives with respect to the different coordinates. The space $\mathcal{D}_{\lambda\mu}$ and the associated graded space of symbols $\mathcal{S}_{\delta}$ ($\delta=\mu-\lambda$) can be considered as $\mathfrak{spo}(2|2)$-modules, where $\mathfrak{spo}(2|2)$ is the Lie superalgebra of contact projective vector fields on $S^{1|2}$. We show in this paper that there is a unique isomorphism of $\mathfrak{spo}(2|2)$-modules between $\mathcal{S}_{\delta}$ and $\mathcal{D}_{\lambda\mu}$ that preserves the principal symbol (i.e. an $\mathfrak{spo}(2|2)$-equivariant quantization) for some values of $\delta$ called non-critical values. Moreover, we give an explicit formula for this isomorphism, extending in this way the results of [Mellouli N., SIGMA 5 (2009), 111, 11 pages, arXiv:0912.5190] which were established for second-order differential operators. The method used here to build the $\mathfrak{spo}(2|2)$-equivariant quantization is the same as the one used in [Mathonet P....

Composite Fermion Geometric Resonance Near {\nu} = 1/2 Fractional Quantum Hall State

Mueed, M. A.; Kamburov, D.; Hasdemir, S.; Shayegan, M.; Pfeiffer, L. N.; West, K. W.; Baldwin, K. W.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We observe geometric resonance features of composite fermions on the flanks of the even denominator {\nu} = 1/2 fractional quantum Hall state in high-mobility two-dimensional electron and hole systems confined to wide GaAs quantum wells and subjected to a weak, strain-induced, unidirectional periodic potential modulation. The features provide a measure of how close to {\nu} = 1/2 the system stays single-component and supports a composite fermion Fermi sea before transitioning into a {\nu} = 1/2 fractional quantum Hall state, presumably the two-component {\Psi}331 state.

Fractional Quantum Hall Effect at $\nu=1/2$ in Hole Systems Confined to GaAs Quantum Wells

Liu, Yang; Graninger, A. L.; Hasdemir, S.; Shayegan, M.; Pfeiffer, L. N.; West, K. W.; Baldwin, K. W.; Winkler, R.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 29/01/2014 Português
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We observe fractional quantum Hall effect (FQHE) at the even-denominator Landau level filling factor $\nu=1/2$ in two-dimensional hole systems confined to GaAs quantum wells of width 30 to 50 nm and having bilayer-like charge distributions. The $\nu=1/2$ FQHE is stable when the charge distribution is symmetric and only in a range of intermediate densities, qualitatively similar to what is seen in two-dimensional electron systems confined to approximately twice wider GaAs quantum wells. Despite the complexity of the hole Landau level structure, originating from the coexistence and mixing of the heavy- and light-hole states, we find the hole $\nu=1/2$ FQHE to be consistent with a two-component, Halperin-Laughlin ($\Psi_{331}$) state.

Searches for New Physics in the Standard Model's Electroweak Sector: Quartic Anomalous Couplings with Vector Boson Fusion and Flavor Changed Neutral Current in the $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ model

Teles, Patricia Rebello
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/03/2013 Português
Relevância na Pesquisa
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In this thesis we investigated, at partonic level and leading order, the LHC potencial operating with $\sqrt{s}=14$ TeV and integrated luminosity of $L=100\;{fb}^{-1}$ to probe "pure" (without triple vertex contributions) anomalous electroweak quartic couplings, $WWWW$ and $WWZZ$, in the semileptonic $pp \rightarrow l^{\pm}\nu_{l}jjjj$ channel, enhanced by the Vector Boson Fusion collider signatures. Deviations on SM quartic couplings were parameterized in a model independent approach, realized linearly ($L_{S0}$ and $L_{S1}$ operators) or not ($L_{4}$ and $L_{5}$ operators), on the basis of effective lagrangians. Being our analysis essentially events counting-and-cut based, we took into account all possible backgrounds (irreducible, QCD and top quarks processes) considered at ${\cal O}(\alpha_{em}^{6})$, ${\cal O(\alpha_{em}^{4}\alpha_{s}^{2})$ and ${\cal O}(\alpha_{em}^{2}\alpha_{s}^{4})$. In this way, we have obtained the following constraints for the non-linear $\alpha_{4}$ and $\alpha_{5}$ anomalous couplings: $|\alpha_{4,5}| \lesssim 0.01$ to 0.02 at 3$\sigma$. Based on non-linear results, we have estimated, for a specific choice of factorization and renormalization scale, the linear parameters $f_{0}$ and $f_{1}$ constraints as $-22 \leq \dfrac{f_{0}}{\Lambda^{4}}\;({TeV}^{-4}) \leq 20...