2,151 research outputs found

    From identical S- and P-wave pT/M spectra to maximally distinct polarizations: probing NRQCD with chi states

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    A global analysis of ATLAS and CMS measurements reveals that, at mid-rapidity, the directly-produced Ōác1\chi_{c1}, Ōác2\chi_{c2} and J/Ōą\psi mesons have differential cross sections of seemingly identical shapes, when presented as a function of the mass-rescaled transverse momentum, pT/Mp_{\rm T}/M. This identity of kinematic behaviours among S- and P-wave quarkonia is certainly not a natural expectation of non-relativistic QCD (NRQCD), where each quarkonium state is supposed to reflect a specific family of elementary production processes, of significantly different pTp_{\rm T}-differential cross sections. Remarkably, accurate kinematic cancellations among the variegated NRQCD terms (colour singlets and octets) of its factorization expansion can lead to a surprisingly good description of the data. This peculiar tuning of the NRQCD mixtures leads to a clear prediction regarding the Ōác1\chi_{c1} and Ōác2\chi_{c2} polarizations, the only observables not yet measured: they should be almost maximally different from one another, and from the J/Ōą\psi polarization, a striking exception in the global panorama of quarkonium production. Measurements of the difference between the Ōác1\chi_{c1}, Ōác2\chi_{c2} and J/Ōą\psi polarizations, complementing the observed identity of momentum dependences, represent a decisive probe of NRQCD.Comment: Submitted to European Physical Journal

    The Graphicahedron

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    The paper describes a construction of abstract polytopes from Cayley graphs of symmetric groups. Given any connected graph G with p vertices and q edges, we associate with G a Cayley graph of the symmetric group S_p and then construct a vertex-transitive simple polytope of rank q, called the graphicahedron, whose 1-skeleton (edge graph) is the Cayley graph. The graphicahedron of a graph G is a generalization of the well-known permutahedron; the latter is obtained when the graph is a path. We also discuss symmetry properties of the graphicahedron and determine its structure when G is small.Comment: 21 pages (European Journal of Combinatorics, to appear

    Asymmetric microbial reduction of ketones: absolute configuration of trans-4-ethyl-1-(1S-hydroxyethyl)cyclohexanol

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    A set of five fungal species, Botrytis cinerea, Trichoderma viride and Eutypa lata, and the endophytic fungi Colletotrichum crassipes and Xylaria sp., was used in screening for microbial biocatalysts to detect monooxygenase and alcohol dehydrogenase activities (for the stereoselective reduction of carbonyl compounds). 4-Ethylcyclohexanone and acetophenone were biotransformed by the fungal set. The main reaction pathways involved reduction and hydroxylations at several positions including tertiary carbons. B. cinerea was very effective in the bioreduction of both substrates leading to the chiral alcohol (S)-1- phenylethanol in up to 90% enantiomeric excess, and the cis‚Äďtrans ratio for 4-ethylcyclohexanol was 0:100. trans-4-Ethyl-1-(1S-hydroxyethyl)cyclohexanol, obtained from biotransformation by means of an acyloin-type reaction, is reported here for the first time. The absolute configurations of the compounds trans-4-ethyl-1-(1S-hydroxyethyl)cyclohexanol and 4-(1S- and 4-(1R-hydroxyethyl)cyclohexanone were determined by NMR analysis of the corresponding Mosher‚Äôs esters

    Maternidade transnacional: o exercício da maternidade por mulheres que imigraram sem os filhos

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    O presente projeto pretende fazer um estudo te√≥rico e emp√≠rico sobre as mulheres que imigram; geralmente de pa√≠ses pobres ou em desenvolvimento para pa√≠ses ricos e desenvolvidos, em busca de melhores condi√ß√Ķes de vida; e deixam para tr√°s os filhos, muitas vezes com menos de um ano de idade, por longos per√≠odos de tempo. O estudo, no entanto deixar√° um pouco de lado os impactos financeiros do fen√īmeno migrat√≥rio e das rela√ß√Ķes transnacionais e se focar√° mais nestas pessoas e nas consequ√™ncias de ordem social sobre as mesmas, especialmente as m√£es imigrantes, nomeadamente os efeitos sobre a subjetividade e o bem-estar, as rela√ß√Ķes interpessoais e os comportamentos e pr√°ticas de um modo geral.This project aims to make a theoretical and empirical study about women who immigrate, generally from poor or developing countries to rich and developed countries in search of better living conditions, and leave behind their children, often with less than one year of age for long periods of time. The study, nevertheless leave a little aside the financial impacts of the migratory phenomenon and the transnational relations and will focus more on these people and the social order‚Äôs consequences on them, especially the immigrant mothers, including the effects on subjectivity and well-being, interpersonal relationships and behaviors and practices in a general way

    A efetividade jur√≠dica brasileira da prote√ß√£o de dados n√£o divulgados e suas implica√ß√Ķes no setor da ind√ļstria farmac√™utica

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    Este trabalho analisa a controv√©rsia do atual regime de prote√ß√£o de informa√ß√Ķes confidenciais, que s√£o confiados √°s ag√™ncias reguladoras governamentais, a fim de obter a aprova√ß√£o de comercializa√ß√£o dos medicamentos para uso humano. Nesta √°rea, encontram-se, claramente, os direitos de propriedade e desenvolvimento tecnol√≥gico em confronto com o direito de acesso da popula√ß√£o a medicamentos de baixo custo. Analisa-se tamb√©m o regime nacional de medicamentos gen√©ricos e similares, tendo em vista a atual pol√≠tica adotada pelo governo brasileiro para o desenvolvimento desses medicamentos

    Toranja, O Jogo : experiências com um Objeto de Aprendizagem no ensino das Artes Visuais na Educação Básica

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    Monografia (gradua√ß√£o)‚ÄĒUniversidade de Bras√≠lia, Instituto de Artes, Departamento de Artes Visuais, 2014.O presente trabalho investiga a cerca das potencialidades e experi√™ncias que podem surgir a partir do uso de um Objeto de Aprendizagem nas aulas de Artes Visuais, e um OA foi desenvolvido e aplicado em grupos focais para este fim. O objetivo desta pesquisa √© investigar sobre os benef√≠cios e desafios que este recurso poderia trazer para o √Ęmbito das aulas de Artes Visuais. Conceitualmente, s√£o aqui exploradas as id√©ias de Johan Huizinga acerca do Homo ludens, de John Dewey e a arte como experi√™ncia, bem como o trabalho de artistas contempor√Ęneos que dialoguem com estas propostas, como o grupo Fluxus e os neoconcretos Lygia Clark e Helio Oiticica. Esta pesquisa √© de car√°ter qualitativo, com an√°lise da experi√™ncia de tr√™s grupos focais, entrevistas, question√°rios estruturados e observa√ß√Ķes in loco. _____________________________________________________________________________ ABSTRACTThis study investigates about the potentials and experiences that may arise from the use of a Learning Object in Visual Arts classes, and a LO was developed and applied in focus groups for this purpose. The objective of this research is to investigate the benefits and challenges that this feature could bring to the scope of Visual Arts classes. Conceptually, here are explored Johan Huizinga's ideas about Homo ludens, John Dewey and the art as experience, as well as the work of contemporary artists that communicate with these proposals, as the Fluxus group and the neoconcrete artists Lygia Clark and Helio Oiticica. This research is qualitative, with analysis of the experience of three focus groups, interviews, structured questionnaires and on-site observations

    A road map for designing and reporting clinical trials in paediatric dentistry

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    Background Unless clinical trials are well‚Äźdesigned, there is a risk that they will not be usable to improve patient care. Aim This paper discusses some factors important in designing clinical trials in paediatric dentistry. It uses the prevention and management of dental caries in children as the lens through which to look at these. Findings Amongst the factors to consider are clear research questions and objectives; appropriate outcomes and outcome measures; sample size calculation and the level of randomisation; methods for random allocation; and operator/assessor training. Experts in trial design including statisticians and a trialist should be consulted early in the design process. The aspects of trial design unique to cariology trials such as ‚Äėclustering‚Äô of data items, mixed dentition issues and those related to trials involving children (communication, consent etc) should be considered. Comprehensive reporting of trial results is essential. Conclusion There are many readily available resources and tools to help the researcher design a trial of good quality that will yield results useful to the research community and beyond, to those who will implement the findings and ultimately those who will benefit from them
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