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41.
Infant death certificates were linked with birth certificates for infants born to residents of Tohoku, Tokai and Kyushu regions in 1989 (n = 409, 679, or about one-third of all births in Japan), to examine the effects of variables, as reported on birth certificates, on cause-specific infant mortality. "Certain conditions originating in the perinatal period" and "congenital anomalies" accounted for nearly 90 percent of neonatal deaths, while "congenital anomalies", "injuries and poisoning" and "sudden infant death" were responsible for about 65 percent of postneonatal deaths. Mortality rates for almost all causes of infant deaths, except injuries and poisonings, increased as birth weight decreased not only in the neonatal period but also in the postneonatal period. This suggests that low birth weight places some infants at higher risk of death, and conditions that lead to low birth weight independently contribute to the risk of infant death. Cox's proportional hazards linear model was used to assess the effects of variables on infant mortalities by causes of death. An extremely strong birth weight effect was noted for "certain conditions originating in the perinatal period" and "congenital anomalies". Being a male infant and late order of birth in multiparity were other risk factors for deaths from "congenital anomalies", while being a male infant, resident of Tohoku region and maternal stillbirth experience related to deaths from "certain conditions originating in the perinatal period". Elevated risks of sudden infant death syndrome (SIDS), of which mortality rate in Japan was considerably lower than those in most developed Western countries, i.e. 0.23 per 1,000 live births in 1989, were associated with low birth weight, being a male infant, low maternal age, late order of birth in multiparity and illegitimacy. Low maternal age, late order of birth in multiparity and illegitimacy, also, related significantly to increased risk of infant deaths for "injuries and poisoning". These results suggest the independent contributions of socioeconomic factors to infant mortality, especially postneonatal mortality, from SIDS, "injuries and poisonings". 相似文献
42.
Oriented poly-p-phenylene sulphide (PPS) films (thickness 12 and 75 m) and PPS powder were carbonized/graphitized after stabilizing by oxidation, in order to examine the effect of sulphur on graphitizability of the resulting carbons. The films and the powder resulted in carbons with a high and a low graphitizability respectively. An in-plane oriented structure of the PPS film was the most predominant factor to lead to a high graphitizability, and sulphur in the precursor did not lower the graphitizability when it was subjected to solid-phase carbonization. These phenomena are discussed on the basis of analytical data. 相似文献
43.
In La2–x
Ba
x
CuO4 (LBCO) the transition to a low-temperature tetragonal phase and the suppression of superconductivity occur at the carrier concentration p 1/8 per copper. We will discuss the roles of various material parameters that control this instability. An unusual lattice softening has been found by ultrasonic measurement on La2–x
Sr
x
CuO4 (LSCO). This softening is present only in an in-plane shearing mode and is ascribed to the growth of structural fluctuations in the normal state.These phenomena are closely related because both the structural change in LBCO and the applied strain in LSCO lift the degeneracy of in-plane oxygen sites. They clarify the importance of strong coupling between the normal-state electronic system and the lattice by a Peierls-type mechanism. 相似文献
44.
45.
Correlation between Chemical Dopants and Topological Defects in Catalytically Active Nanoporous Graphene 下载免费PDF全文
46.
K. Yoshida Y. Maeno S. Nishizaki S. Ikeda T. Fujita 《Journal of Low Temperature Physics》1996,105(5-6):1593-1598
We have investigated the normal-state conduction of superconducting Sr2RuO4 (Tc 1K), which is isostructural to La2–xSrxCuO4. The resistivity of single crystals shows a crossover at TM130K from 3D metallic conduction at lower temperatures to 2D one at higher temperatures. Concerning the temperature dependence of the out-of-plane resistivity, we present a systematic interpretation based on competition between the life time of the quasiparticles and the time for the quasiparticles to travel between the adjacent RuO2 planes. 相似文献
47.
In maintenance of concrete structures, crack detection is important for the inspection and diagnosis of concrete structures.
However, it is difficult to detect cracks automatically. In this paper, we propose a robust automatic crack-detection method
from noisy concrete surface images. The proposed method includes two preprocessing steps and two detection steps. The first
preprocessing step is a subtraction process using the median filter to remove slight variations like shadings from concrete
surface images; only an original image is used in the preprocessing. In the second preprocessing step, a multi-scale line
filter with the Hessian matrix is used both to emphasize cracks against blebs or stains and to adapt the width variation of
cracks. After the preprocessing, probabilistic relaxation is used to detect cracks coarsely and to prevent noises. It is unnecessary
to optimize any parameters in probabilistic relaxation. Finally, using the results from the relaxation process, a locally
adaptive thresholding is performed to detect cracks more finely. We evaluate robustness and accuracy of the proposed method
quantitatively using 60 actual noisy concrete surface images. 相似文献
48.
Sarah Mostame Joonsuk Huh Christoph Kreisbeck Andrew J. Kerman Takatoshi Fujita Alexander Eisfeld Alán Aspuru-Guzik 《Quantum Information Processing》2017,16(2):44
With quantum computers being out of reach for now, quantum simulators are alternative devices for efficient and accurate simulation of problems that are challenging to tackle using conventional computers. Quantum simulators are classified into analog and digital, with the possibility of constructing “hybrid” simulators by combining both techniques. Here we focus on analog quantum simulators of open quantum systems and address the limit that they can beat classical computers. In particular, as an example, we discuss simulation of the chlorosome light-harvesting antenna from green sulfur bacteria with over 250 phonon modes coupled to each electronic state. Furthermore, we propose physical setups that can be used to reproduce the quantum dynamics of a standard and multiple-mode Holstein model. The proposed scheme is based on currently available technology of superconducting circuits consist of flux qubits and quantum oscillators. 相似文献
49.
An energy eigenvalue equation for a quasi-particle is derived, starting with the Heisenberg equation of motion for an annihilation operator. An elementary derivation of the Fermi liquid model having a sharply defined Fermi surface in thek-space is given, starting with a realistic model of a metal including the Coulomb interaction amongand between electrons and lattice-ions. The Ginzburg-Landau wave function
(r), where represents the superconducting pairon (Cooper-pair) state, is shown to be connected with the one-pairon density operatorn by
(r) = r¦n
1/2¦. A close analogy between supercurrent and laser is indicated.On sabbatical leave from Department of Physics and Astronomy, State University of New York at Buffalo, Buffalo, New York. 相似文献
50.
In this study, a three-point bendJ lc fracture-toughness test was carried out using four types of structural steels at room temperature. The values of (γ p)V, which represent the width of the region where the voids are located just ahead of the crack tip, were measured by Beacham's method [9] with the help of a scanning electron microscope (SEM). The experimental (γ p) values and the theoretical values obtained using the finite element method (FEM) or calculated fromK at initiation are in good agreement. It was found that there is a certain linear relationship between (γ p)Vand the stretched zone width (SZW), and an experimental relationship betweenJ lc andσ flow·(γ p)V which may be expressed by the following equation: $$J_{lc} = 44.1 + 0.35\sigma _{{\text{flow}}} \cdot (\gamma _{\text{p}} )V_c KJ$$ whereσ flow is the average value of the yield stress and the ultimate tensile strength. (γ p)V c represents the critical value of (γ p)V. The numerical constant 44.1 kJ m?2 is considered to be aJ lc value for brittle fracture of the material tested, according to the authors' previous results. It is possible to calculateJ lc if (γ p)V c can be measured. 相似文献