995 resultados para R-square


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A gravidez é uma fase especial da vida, com diversas alterações nos sistemas hormonais, anatómicos, e na composição corporal da mulher. No entanto, não é claro que alterações biomecânicas tridimensionais ocorrerem. Através do acompanhamento da mulher na gravidez e pós-parto, os objetivos da presente tese foram: 1) determinar os parâmetros temporais e espaciais do ciclo da marcha; 2) descrever a cinemática angular do membro inferior; 3) calcular os momentos e potências articulares do tornozelo, joelho e coxofemoral, utilizando o cálculo por dinâmica inversa; 4) descrever as magnitudes dos picos dos momentos e potências articulares dos membros inferiores; 5) identificar possíveis diferenças entre as fases de recolha relativamente aos parâmetros biomecânicos; 6) descrever longitudinalmente a composição corporal as alterações morfológicas; 7) analisar a influência das alterações antropométricas na cinética articular. Os resultados mostram que as mulheres mantêm os parâmetros temporais e espaciais da marcha. A cinemática angular do membro inferior tem o mesmo padrão, no entanto, a magnitude de alguns picos, especialmente na bacia e coxofemoral durante a fase terminal do apoio, pré-balanço e de balanço, apresentam alterações significativas. A coxofemoral é a articulação com mais alterações na cinética articular, com um aumento da carga interna associada aos momentos articulares da coxofemoral no plano transversal. No entanto, diversos momentos e potências articulares revelam uma diminuição significativa para o final da gravidez e/ou um aumento entre alguns trimestres da gravidez e o pós-parto. Como esperado, a maioria das variáveis associadas à composição corporal e às dimensões corporais tem um aumento significativo durante a gravidez e uma diminuição no pós-parto. Os modelos desenvolvidos para prever a carga interna aplicada ao membro inferior da grávida através de variáveis antropométricas, incluem quatro modelos com variáveis associadas à quantidade de gordura, quatro modelos com variáveis associadas à massa corporal global, três modelos que incluem a massa livre de gordura, e um modelo que inclui a forma do tronco. Os altos valores do R2 ajustado, mostram que as alterações na composição corporal e morfologia, determinam em grande parte a cinética articular da mulher nesta fase particular da vida.

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The purpose of this research is to develop a new statistical method to determine the minimum set of rows (R) in a R x C contingency table of discrete data that explains the dependence of observations. The statistical power of the method will be empirically determined by computer simulation to judge its efficiency over the presently existing methods. The method will be applied to data on DNA fragment length variation at six VNTR loci in over 72 populations from five major racial groups of human (total sample size is over 15,000 individuals; each sample having at least 50 individuals). DNA fragment lengths grouped in bins will form the basis of studying inter-population DNA variation within the racial groups are significant, will provide a rigorous re-binning procedure for forensic computation of DNA profile frequencies that takes into account intra-racial DNA variation among populations. ^

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Photo-lithoprint reproduction. Ann Arbor, Mich., Edwards Bros., 1947.

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Three distinct coordination complexes, viz., [Co(imi)(2)(tmb)(2)] (1) [where imi = imidazole], {[Ni(tmb)(2)(H2O)(3)]center dot 2H(2)O}(n) (2) and [Cu-2(mu-tmb)(4)(CH3OH)(2)] (3), have been synthesized hydrothermally by the reactions of metal acetates,2,4,6-trimethylbenzoic acid (Htmb) and with or without appropriate amine. The Ni analogue of 1 and the Co analogue of 2 have also been synthesized. X-ray single-crystal diffraction suggests that complex 1 represents discrete mononuclear species and complex 2 represents a 1D chain coordination polymer in which the Ni(H) ions are connected by the bridging water molecules. Complex 3 represents a neutral dinuclear complex. In 1, the central metal ions are associated by the carboxylate moiety and imidazole ligands, whereas the central metal atom is coordinated to the carboxylate moiety and the respective solvent molecules in 2 and 3. In 3, the four 2,4,6-trimethylbenzoate moieties act as a bridge connecting two copper (11) ions and the 0 atoms of methanol coord geometry, with the methanol molecule at the apical position. In all the three structures the central metal atom sits on a crystallographic inversion centre. In all the cases, the coordination entities are further organized via hydrogen bonding interactions to generate multifarious supramolecular networks. Complexes 1, 2 and 3 have also been characterized by spectroscopic (UV/Vis and IR) and thermal analysis (TGA). In addition, the complexes were found to exhibit antimicrobial activity. The magnetic susceptibility measurements, measured from 8 to 300 K, revealed antiferromagnetic interactions between the Co(II) ions in compound 1 and the Ni(II) ions in la, respectively.

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This paper presents a generalized approach to design an electromagnetically coupled microstrip ring antenna for dual-band operation. By widening two opposite sides of a square ring antenna, its fractional bandwidth at the primary resonance mode can be increased significantly so that it may be used for practical applications. By attaching a stub to the inner edge of the side opposite to the feed arm, some of the losses in electrical length caused by widening can be regained. More importantly, this addition also alters the current distribution on the antenna and directs radiations at the second resonant frequency towards boresight. It has also been observed that for the dual frequency configurations studied, the ratio of the resonant frequencies (center dot r(2)center dot center dot r(1)) can range between 1.55 and 2.01. This shows flexibility in designing dual frequency antennas with a desired pair of resonant frequencies.

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Oxygen transfer rate and the corresponding power requirement to operate the rotor are vital for design and scale-up of surface aerators. Present study develops simulation or scale-up criterion correlating the oxygen transsimulation fer coefficient and power number along with a parameter governing theoretical power per unit volume (X, which is defined as equal to (FR1/3)-R-4/3, where F and R are impellers' Fronde and Reynolds number, respectively). Based on such scale-up criteria, design considerations are developed to save energy requirements while designing square tank surface aerators. It has been demonstrated that energy can be saved substantially if the aeration tanks are run at relatively higher input powers. It is also demonstrated that smaller sized tanks are more energy conservative and economical when compared to big sized tanks, while aerating the same volume of water, and at the same time by maintaining a constant input power in all the tanks irrespective of their size. An example illustrating how energy can be reduced while designing different sized aerators is given. The results presented have a wide application in biotechnology and bioengineering areas with a particular emphasis on the design of appropriate surface aeration systems.

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Oxygen transfer rate and the corresponding power requirement to operate the rotor are vital for design and scale-up of surface aerators. Present study develops simulation or scale-up criterion correlating the oxygen transsimulation fer coefficient and power number along with a parameter governing theoretical power per unit volume (X, which is defined as equal to (FR1/3)-R-4/3, where F and R are impellers' Fronde and Reynolds number, respectively). Based on such scale-up criteria, design considerations are developed to save energy requirements while designing square tank surface aerators. It has been demonstrated that energy can be saved substantially if the aeration tanks are run at relatively higher input powers. It is also demonstrated that smaller sized tanks are more energy conservative and economical when compared to big sized tanks, while aerating the same volume of water, and at the same time by maintaining a constant input power in all the tanks irrespective of their size. An example illustrating how energy can be reduced while designing different sized aerators is given. The results presented have a wide application in biotechnology and bioengineering areas with a particular emphasis on the design of appropriate surface aeration systems.

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Self-assembly of a rigid tripyridyl linker with a bidentate 90 degrees Pt(II) acceptor yielded a somewhat unusual double square cage, representing the first example of Pt(II) cage of such shape. Multinuclear NMR as well as single-crystal structure analysis characterized the cage.

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Self-assembly of a rigid tripyridyl linker with a bidentate 90 degrees Pt(II) acceptor yielded a somewhat unusual double square cage, representing the first example of Pt(II) cage of such shape. Multinuclear NMR as well as single-crystal structure analysis characterized the cage.

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A method is presented for obtaining lower bound on the carrying capacity of reinforced concrete foundation slab-structures subject to non-uniform contact pressure distributions. Functional approach suggested by Vallance for simply supported square slabs subject to uniform pressure distribution has been extended to simply supported rectangular slabs subject to symmetrical non-uniform pressure distributions. Radial solutions, ideally suited for rotationally symmetric problems, are shown to be adoptable for regular polygonal slabs subject to contact pressure paraboloids with constant edge pressures. The functional approach has been shown to be well suited even when the pressure is varying along the edges.

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We report the C-HETSERF experiment for determination of long- and short-range homo- and heteronuclear scalar couplings ((n)J(HH) and (n)J(XH), n >= 1) of organic molecules with a low sensitivity dilute heteronucleus in natural abundance. The method finds significant advantage in measurement of relative signs of long-range heteronuclear total couplings in chiral organic liquid crystal. The advantage of the method is demonstrated for the measurement of residual dipolar couplings (RDCs) in enantiomers oriented in the chiral liquid crystal with a focus to unambiguously assign R/S designation in a 2D spectrum. The alignment tensor calculated from the experimental RDCs and with the computed structures of enantiomers obtained by DFT calculations provides the size of the back-calculated RDCs. Smaller root-mean-square deviations (rmsd) between experimental and calculated RDCs indicate better agreement with the input structure and its correct designation of the stereogenic center.

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Directional emission triangle and square InGaAsP/InP lasers have been fabricated by standard photolithography, inductively coupled plasma etching technique combined with wet chemical etching process. In this article, the characteristics of the microcavity lasers are presented. For an equilateral triangle microcavity laser with the side length of 30 mu m, we got the laser spectra fitted very well with the mode wavelength formulate LIP to the 8(th) transverse mode at room temperature. But the laser spectra are usually more complex than the formulae for the lasers, especially for the lasers with a smaller side length. For a square microcavity laser with side length of 20 mu m, we observed the mode competition between the Fabry-Perot (FP) modes and Whispering-Gallery (WG) modes at 200K. The output spectra below the threshold have the mode interval of FP modes with a large mode interval, and the laser spectra agree very well with the WG modes, which have mode interval less than the FP modes. The output spectra are dominated by the FP modes below the threshold, because the FP modes have a higher output coupling efficiency than the WG modes.

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Output coupling efficiencies are analyzed for triangular and square microlasers connected with an output waveguide by FDTD simulation. The results show that square resonator with an output waveguide connected to the midpoint of one side can have high output coupling efficiency and a good mode selection.