RCAAP - Repositório Científico de Acesso Aberto de Portugal
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Effects of sexual maturation on blood pressure of male children and adolescents with different body mass, height and cronological age
No full textO presente estudo tem como objetivo responder à seguinte questão: os efeitos da maturação sexual (MS) sobre os níveis de pressão arterial sistólica (PAS) e diastólica (PAD) em crianças e adolescentes do sexo masculino, entre oito e 15 anos, estudantes de 30 escolas da área periférica e central do Porto, são independentes dos efeitos das variáveis de crescimento corporal: estatura (EST); massa corporal (MC); e idade cronológica (IC)? As variáveis antropométricas EST e MC foram avaliadas segundo a metodologia proposta pelo COUNCIL OF EUROPE (1988). A pressão arterial (PA) foi medida de acordo com os métodos propostos por GILLMAN e COOK (1995) e DE SWIET et al., (1989). A amostra foi agrupada de acordo com os cinco estágios maturacionais descritos por TANNER (1962). Optou-se pela pilosidade como característica sexual secundária para a classificação pubertária dos meninos (MARTIN et al., 2001; MATSUDO & MATSUDO, 1994). Os resultados do presente estudo sugerem que os valores de PAS sofrem influência do processo de MS (Anova). Todavia quando controlou-se os efeitos das variáveis EST e MC as diferenças deixaram de ser estatisticamente significativas. Da mesma forma quando controlou-se os efeitos da IC a PAS apresentou diferença estatisticamente significativa apenas entre os estágios II e IV. Os resultados possibilitam concluir que os níveis de PA em crianças e adolescentes do sexo masculino, não devem ser determinados pelos estágios de MS independentemente de considerar-se os efeitos dissociados das variáveis EST, MC e IC.The aim of this study was to analyse if the effects of sexual maturation (SM) on sistolic blood pressure (SBP) and diastolic blood pressure (DBP) are independent of body growth (height, weight, chronological age), in boys aged 8-15 years old. Height and weight were determined by standard anthropometric methods (COUNCIL OF EUROPE, 1988). Blood pressure (BP) was measured according to standard methods (GILLMAN & COOK, 1995). Pubic hair was chosen as a secondary sexual characteristic for the puberty classification in boys (MATSUDO & MATSUDO, 1994; TANNER, 1962). The results of the present study show that SBP is influenced by SM (Anova). Results of the Ancova, with height and weight as the covariates, did not show statistically significant differences. When chronological age is the covariate, the BP shows statistically significant differences only between SM stages II and IV. Conclusion: Boys BP should not be determined by SM alone. The effects of height, weight and chronological age should be considered
Noncommutative quantum mechanics as a gauge theory
No full textThe classical counterpart of noncommutative quantum mechanics is a constrained system containing only second-class constraints. The embedding procedure formulated by Batalin, Fradkin and Tyutin (BFT) enables one to transform this system into an Abelian gauge theory exhibiting only first class constraints. The appropriateness of the BFT embedding, as implemented in this work, is verified by showing that there exists a one to one mapping linking the second-class model with the gauge invariant sector of the gauge theory. As is known, the functional quantization of a gauge theory calls for the elimination of its gauge freedom. Then, we have at our disposal an infinite set of alternative descriptions for noncommutative quantum mechanics, one for each gauge. We study the relevant features of this infinite set of correspondences. The functional quantization of the gauge theory is explicitly performed for two gauges and the results compared with that corresponding to the second-class system. Within the operator framework the gauge theory is quantized by using Dirac’s method
Interconnection between zero resistance and magnetic irreversibility temperatures in the hole doped Y0.9Ca0.1Ba2Cu3O7-δ single crystal
No full textLow Sr doping effects on critical current density and pinning mechanism of YBa2Cu3O7-δ single crystals
No full text
Phase diagrams of three-component attractive ultracold fermions in one dimension
No full textWe investigate trions, paired states and quantum phase transitions in one-dimensional SU(3) attractive fermions in external fields by means of the Bethe ansatz formalism. Analytical results for the ground state energy, critical fields and complete phase diagrams are obtained for the weak coupling regime. Higher-order corrections for these physical quantities are presented in the strong attractive regime. Numerical solutions of the dressed energy equations allow us to examine how the different phase boundaries are modified by varying the intercomponent coupling throughout the whole attractive regime. The pure trionic phase existing in the strong coupling regime decreases smoothly with a decrease in this coupling, until the weak limit is reached. In this weak regime, a pure Bardeen–Cooper–Schrieffer (BCS)-like paired phase can be sustained under certain nonlinear Zeeman splittings
Exclusive photoproduction of J/ψ and ψ(2S) states in proton-proton collisions at the CERN LHC
No full textIn this work we investigate the exclusive photoproduction of J=c and the radially excited c ð2SÞ state off nucleons in proton-proton collisions. The theoretical framework considered in the analysis is the light-cone dipole formalism and predictions are done for proton-proton collisions at the CERN-LHC energy of 7 TeV. The theoretical uncertainties are investigated and a comparison is made to the recent LHCb Collaboration data for the exclusive charmonium production
Confinement effects of ion tracks in ultrathin polymer films
No full textWe show direct experimental evidence that radiation effects produced by single MeV heavy ions on a polymer surface are weakened when the length of the ion track in the material is confined into layers of a few tens of nanometers. Deviation from the bulk (thick film) behavior of ion-induced craters starts at a critical thickness as large as ∼40 nm, due to suppression of long-range additive effects of excited atoms along the track. Good agreement was found between the experimental results, molecular dynamic simulations, and an analytical model
Culinária do Seridó: um elemento da identidade territorial
No full textEste trabalho tem por objetivo analisar a culinária local como um elemento da identidade
territorial do Seridó norte-rio-grandense na contemporaneidade século XXI, onde acontece
um movimento, aparentemente contraditório, no entanto dialógico, em que o modo de comer
local é modificado pela diversidade alimentar e ao mesmo tempo é enaltecido como elemento
de resistência, isto é, de identificação. Baseados na perspectiva de que os grupos vão, ao
longo do tempo, delineando no território suas características culturais alimentar, verificamos
que a espacialização da culinária local aconteceu durante o processo de estruturação
territorial, estando suscetível às mudanças sociais, econômicas e tecnológicas, que pairam
sobre esse espaço. No desenrolar cotidiano criou-se toda uma semiologia em volta da
culinária, incorporando ao seu território de vivência, símbolos, imagens, saberes, sabores,
sentimentos e cheiros que legitimam um modo de ser, melhor dizendo, de comer. Mas não são
todos os seus pratos que congregam esses aspectos, só os mais antigos, os mais emblemáticos.
Com os diversos intercruzamentos de cultura, no Seridó, são eles que mantêm o vínculo do
grupo com sua cultura e com seu território, fazendo-os lembrar o que são , ou pelo menos,
o que foram , conferindo-lhes uma legitimidade perante os demais com os quais se
relacionam. A culinária seridoense, dessa maneira, é um geossímbolo cultural que torna esse
espaço significativo e visível, por ordenar as características internas do grupo diante de novos
modelos socioculturais existentes no territórioThis work aims to analyze the local cuisine as an element of territorial identity from Seridó
Rio Grande do Norte State in the contemporaneousness - XXI century, where it takes place
one motion, seemly contradictory, yet dialogical, in the way of eating locally is modified by
food diversity and yet is lauded as an element of resistance, that is, of identification. Based on
the perspective that groups go over time outlining on the territory their eating cultural
characteristics, we have noticed that the spatiality from the local cuisine has happened during
the territorial structuring process, being susceptible to the social, economical and
technological changes, that hover over this space. On the unfolding days it was created a
whole semiology around the cookery , incorporating to its territory of living, symbols,
images, knowledge, tastes, feelings and smells that legitimate a way of being, better saying, of
eating. But not all of the plates that congregate these aspects, only the oldest, the most
emblematic. Within the diverse intercrossing of culture at Seridó region, they are the ones that
maintain the vinculum from the group with its culture and with its territory, reminding what
they are, or at least what they were, conferring them a legitimacy before those to whom they
relate. The cookery from the Seridó region, this way is a cultural geo-symbol that turn this
space significant and visible, for ordering the inside characteristics from the group before the
new socio-cultural models present in the territor