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Periodic Breathing in Preterm Infants: Incidence and Characteristics
Pediatrics, 1989The prevalence and characteristics of periodic breathing in preterm infants were measured by 24-hour impedance pneumograms in 66 preterm infants before discharge from the nursery. Four periodic breathing parameters (percentage of periodic breathing per quiet time, number of episodes of periodic breathing per 100 minutes of quiet time, mean duration of ...
S F, Glotzbach +4 more
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Characteristics of resonant periodic orbits
Astrophysics and Space Science, 1982We study the families of periodic orbits in a time-independent two-dimensional potential field symmetric with respect to both axes. By numerical calculations we find characteristic curves of several families of periodic orbits when the ratio of the unperturbed frequencies isA1/2/B1/2=2/1.
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Growth Characteristics of Mouse Thymus in the Neonatal Period
Nature, 1967ALTHOUGH renewed efforts have been made towards an understanding of the function(s) of the thymus, the exact mechanisms involved remain unclear. It is not known whether the thymus serves primarily as a source of immunologically competent cells, or whether it produces a substance or substances and/or contact factors which may control proliferation and ...
M W, Hess, R D, Stoner, H, Cottier
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Alpaca semen characteristics previous to a mating period
Animal Reproduction Science, 2002Increasing the knowledge of the semen characteristics in the alpaca will contribute to understanding one of the many factors that affect the poor fertility rate in this species. Ten adult male alpacas, 2.6-10 years of age, average weight 64.7 +/- 4.7 kg were used.
Flores, Paloma +4 more
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Linear propagation characteristics of periodically segmented waveguides
Optics Letters, 1992Periodically segmented planar waveguides are modeled by using the rigorous modal method of diffraction gratings. The radiation loss, effective index, and electric-field strength distribution are analyzed for different segment duty cycles. It is shown that except for the low radiation loss and possible presence of stop bands, a segmented waveguide ...
L, Li, J J, Burke
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On characteristic polynomials of periodic graphs
Discrete Mathematics and Applications, 2004This work considers periodic graphs of two types, chain and cyclic extensions of an arbitrary graph. Some formulas are obtained which express the characteristic polynomials of such constructions in terms of the polynomials of the initial graphs, their subgraphs and the polynomials of a chain and a cycle.
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Sensory Attenuation Characteristics for Periodic Force Variation
2019 58th Annual Conference of the Society of Instrument and Control Engineers of Japan (SICE), 2019This study aimed to clarify the physiological mechanisms of human perceptual recognition by measuring and evaluating the sensory attenuation response. Here, we have reconstructed an experimental system in order to improve the precision of quantitative measurement and evaluation of sensory attenuation, and in order to look for a novel indicator ...
Atsuo Nuruki +2 more
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Characteristic Periodic Motion of Polymers in Shear Flow
Physical Review Letters, 2005The motion of both free and tethered polymer molecules as well as rigid Brownian rods in unbound shear flow is found to be characterized by a clear periodicity or tumbling frequency. Periodicity is shown using a combination of single molecule DNA experiments and computer simulations.
Charles M, Schroeder +3 more
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Periods of ordinary abelian varieties in characteristic p
Boletim da Sociedade Brasileira de Matem�tica, 1998Let \(A\) be an abelian variety over a field \(K\) of characteristic \(p>0\) and let \(K_s\) be the separable closure of \(K\). Let \(A^{(p^n)}\) be the image of \(A\) under the \(n\)-th power of the Frobenius and \(V_n: A^{(p^n)}\to A\) the dual isogeny. The period lattice of \(A\) is defined by \(\Lambda= \varprojlim \operatorname {Ker} V_n\).
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Citation Characteristics of Periodical Literature in Veterinary Science
American Journal of Veterinary Research, 1977SUMMARY The usage of periodical literature in veterinary science was measured by means of citation analysis. Eighty-two percent of the citations in the source of this study, Advances in Veterinary Science and Comparative Medicine (1970-1974), were from periodicals, and 70 of the 743 periodical titles cited (9.4%) contributed 66% of the total periodical
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