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11.
The hemostatic effect of aprotinin in pediatric cardiac surgery is controversial. This study demonstrated the usefulness of aprotinin in cases undergoing additional surgery. In a retrospective study, three groups of children were investigated. In group I (n = 10), no aprotinin or Cell saver was used (control). In group II (n = 12), Cell saver was used intraoperatively. In group III (n = 14), aprotinin 30,000 KIU/kg was added to the prime of cardiopulmonary bypass, and another 10,000 KIU/kg was given every hour during extracorporeal circulation. Both blood loss and use of homologous blood during operation were significantly (p < 0.01) reduced in group III compared to those in the other two groups. In group III, blood loss both 12 and 48 hours postoperatively were one-third less than those in group I (no significant difference). The use of homologous blood 48 hours postoperatively was significantly reduced in group III compared to that in group I (p < 0.01) or group II (p < 0.05). We conclude that aprotinin administration during cardiopulmonary bypass reduced blood loss and homologous blood requirements both operatively and postoperatively when pediatric cardiac surgery must be redone. 相似文献
12.
13.
Upper and lower critical solution temperatures have been determined for solutions of poly(ethylene glycol) in t-butyl acetate and water over the molecular weight range of Mη = 2.18 × 103 to ~1020 × 103. The phase diagram for solutions of poly(ethylene glycol) (Mη = 719 × 103) in t-butyl acetate was expressed as the ‘hour glass’ type, while the phase diagram for solution of poly(ethylene glycol) (Mη = 2.18 × 103 to ~2.29 × 103) in water was expressed as the ‘closed loop’ type. The value of the pressure dependence of the lower critical solution temperature in the poly(ethylene glycol) (Mη = 1020 × 103)/water system over the pressure range of 0 to ~50 atm was negligibly small and positive. 相似文献
14.
A suitable alloying design for improving the punchability of nonoriented electrical steels containing 0.1 % Si was investigated.
The appropriate addition of sulfur to steels containing relatively high manganese content is very useful in obtaining good
punchability without detrimental effects on magnetic properties. 相似文献
15.
Recently multineuronal recording has allowed us to observe patterned firings, synchronization, oscillation, and global state transitions in the recurrent networks of central nervous systems. We propose a learning algorithm based on the process of information maximization in a recurrent network, which we call recurrent infomax (RI). RI maximizes information retention and thereby minimizes information loss through time in a network. We find that feeding in external inputs consisting of information obtained from photographs of natural scenes into an RI-based model of a recurrent network results in the appearance of Gabor-like selectivity quite similar to that existing in simple cells of the primary visual cortex. We find that without external input, this network exhibits cell assembly-like and synfire chain-like spontaneous activity as well as a critical neuronal avalanche. In addition, we find that RI embeds externally input temporal firing patterns to the network so that it spontaneously reproduces these patterns after learning. RI provides a simple framework to explain a wide range of phenomena observed in in vivo and in vitro neuronal networks, and it will provide a novel understanding of experimental results for multineuronal activity and plasticity from an information-theoretic point of view. 相似文献
16.
Joris Vaillant Abderrahmane Kheddar Hervé Audren François Keith Stanislas Brossette Adrien Escande Karim Bouyarmane Kenji Kaneko Mitsuharu Morisawa Pierre Gergondet Eiichi Yoshida Suuji Kajita Fumio Kanehiro 《Autonomous Robots》2016,40(3):561-580
We describe the research and the integration methods we developed to make the HRP-2 humanoid robot climb vertical industrial-norm ladders. We use our multi-contact planner and multi-objective closed-loop control formulated as a QP (quadratic program). First, a set of contacts to climb the ladder is planned off-line (automatically or by the user). These contacts are provided as an input for a finite state machine. The latter builds supplementary tasks that account for geometric uncertainties and specific grasps procedures to be added to the QP controller. The latter provides instant desired states in terms of joint accelerations and contact forces to be tracked by the embedded low-level motor controllers. Our trials revealed that hardware changes are necessary, and parts of software must be made more robust. Yet, we confirmed that HRP-2 has the kinematic and power capabilities to climb real industrial ladders, such as those found in nuclear power plants and large scale manufacturing factories (e.g. aircraft, shipyard) and construction sites. 相似文献
17.
Xinyue Zhao Author Vitae Yutaka Satoh Author Vitae Author Vitae Shun’ichi Kaneko Author Vitae Author Vitae Ryushi Ozaki Author Vitae 《Pattern recognition》2011,44(6):1296-1311
In this paper, we propose a robust and accurate background model, called grayscale arranging pairs (GAP). The model is based on the statistical reach feature (SRF), which is defined as a set of statistical pair-wise features. Using the GAP model, moving objects are successfully detected under a variety of complex environmental conditions. The main concept of the proposed method is the use of multiple point pairs that exhibit a stable statistical intensity relationship as a background model. The intensity difference between pixels of the pair is much more stable than the intensity of a single pixel, especially in varying environments. Our proposed method focuses more on the history of global spatial correlations between pixels than on the history of any given pixel or local spatial correlations. Furthermore, we clarify how to reduce the GAP modeling time and present experimental results comparing GAP with existing object detection methods, demonstrating that superior object detection with higher precision and recall rates is achieved by GAP. 相似文献
18.
Dependence of self-heating effects on operation conditions and device structures for polycrystalline silicon TFTs 总被引:1,自引:0,他引:1
Takechi K. Nakata M. Kanoh H. Otsuki S. Kaneko S. 《Electron Devices, IEEE Transactions on》2006,53(2):251-257
Self-heating, a degradation mechanism of n-channel poly-Si thin-film transistors (TFTs) due to bias stress, has been investigated. The aim of this work is to study this effect in depth to be able to propose a device structure designed to reduce it. The variation of the threshold voltage (V/sub t/) shift with the stress-pulsewidth is related to the temperature rise due to the self-heating effect that depends on the stress-pulsewidth. Electron trapping in the oxide caused by the bias stress is considered to be enhanced by the TFT temperature rise owing to the self-heating. We show that copper-film-based TFTs, which have a substrate made of an extremely thin glass layer and a copper film exhibit much reduced self-heating and thus a decrease of V/sub t/ shift caused by the bias stress. These observations are interpreted using numerical simulations to estimate the temperature rise in the poly-Si channel region due to Joule heating. 相似文献
19.
Damping characteristics and frequency characteristics of ferro fluid bearing (FFB) spindles were measured using a high-frequency vibration base driven by a piezo actuator. Using the high-frequency vibration base, high-frequency excitation was added to ferro fluid bearing spindles mounted on the vibration base, and it was proved that ferro fluid bearing spindles have effective damping. And the damping effect became larger with higher spindle rotational speed. Also we have measured spindle runout of a ferro fluid bearing spindle using a lock-in amplifier to increase S/N ratio and succeeded to measure nano meter order displacements. 相似文献
20.
Y. Xue S. Asada A. Hosomichi S. Naher J. Xue H. Kaneko H. Suzuki T. Muranaka J. Akimitsu 《Journal of Low Temperature Physics》2005,138(5-6):1105-1115
We have performed powder X-ray diffraction of MgB2 superconductor between 10 and 300 K. Temperature dependence of integrated intensities of both (002) and (110) X-ray reflections shows a peak at around TC, superconducting transition temperature. The integrated intensity of the X-ray reflection is related to the phonon frequency through a Debye--Waller factor. Lattice parameters a and c show negative thermal expansions at low temperatures. The negative thermal expansion might be due to an electronic origin and not directly related to the superconducting transition. 相似文献