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111.
A magnetostrictive-shape memory piezoelectric material composite is proposed to realize a magnet field memory effect. An imprint electrical field enables a shape memory piezoelectric actuator, and the shape memory effect maintains a certain permeability of the magnetostrictive materials. A new magnetic flux memory effect is generated using a composite of the magnetostrictive-shape memory piezoelectric actuator and a permanent magnet. This magnetic flux memory effect can be operated with a pulsed voltage to the shape memory piezoelectric actuator, so that no energy is consumed to maintain a certain magnetic effect.  相似文献   
112.
We have presented two cases of cranioplasty with neovascularized autogenous calvarial bone. A surgical procedure applying the principle of flap prefabrication has been applied to the preservation of autogenous calvarial bone obtained during external cranial decompression. The rectus abdominis muscle flap was elevated. A subcutaneous pocket was prepared for preservation of calvarial bone integrated with the rectus abdominis muscle. The outer cortex of calvarial bone was removed partially by bone chiseling. The muscle flap was attached to the bone graft by means of two holes on the bone by suture. The calvarial bone, grafted onto the rectus abdominis muscle flap, was inserted into the subcutaneous pocket. Several weeks later, the neovascularized calvarial bone flap was dissected along with inferior epigastric pedicle. Cranioplasty was performed using the bone element of the flap. Revascularization was achieved by anastomosing the inferior epigastric vessels to the temporal vessels. The postoperative films demonstrated marked radiolucency at the borders of the flap, although bone scan documented that the flap was vascularized. We speculate that the transferred bony segment was not completely vascularized.  相似文献   
113.
114.
A very low loss single-mode fibre with a minimum loss of 0.20 dB/km at a wavelength of 1.55 ?m is attained; this loss reaches the ultimate lower loss limit of silica-based optical glass fibre. The loss mechanism is also discussed.  相似文献   
115.
The expression of membrane-bound Fas ligand (FasL) and Fas in lymphocytes and monocytes and levels of soluble forms of FasL (sFasL) and Fas (sFas) in plasma from human immunodeficiency virus (HIV)-positive and -negative subjects was evaluated. Surface FasL was detectable on monocytes, but poorly so on lymphocytes, even in the presence of KB8301, a metalloproteinase inhibitor. Unexpectedly, monocytes of HIV-positive subjects expressed less FasL than those of HIV-negative volunteers. sFasL levels in plasma of HIV-positive persons were elevated and correlated with levels in plasma and with HIV RNA burden. sFas levels in plasma of HIV-positive subjects were also elevated and correlated with Fas expression in apoptotic lymphocytes. Finally, culture-induced lymphocyte apoptosis of HIV-positive subjects was enhanced by anti-Fas agonistic antibody but was not inhibited by anti-FasL blocking antibodies. These results suggest that significant dysregulation of both Fas and FasL occurs in HIV infection and contributes to increased sensitivity of lymphocytes to apoptosis.  相似文献   
116.
Fragments of disrupted capsids were frequently seen in purified preparations of human rotavirus inner capsids by negative staining method in electron microscopy. The ultrastructures of these fragments were analyzed in comparison with the T = 13L model. Well-resolved pentamers were rarely seen in the fragments on observation at the standard electron doses, but were frequently seen at low electron doses, which meant a better preservation of the steric structure of capsid fragments in the latter case. Thus advantages of low dose electron microscopy have been shown in observation of capsid fragments.  相似文献   
117.
This paper presents the theoretical and experimental investigations on polarization characteristics of PANDA fiber with flat cladding. It is theoretically shown that the modal birefringence in the flat-clad fiber is almost the same as that in the circular-clad fiber. The flat-clad PANDA fiber has been fabricated by grinding off the preform cladding on the opposite faces and then drawing with a low furnace temperature. The modal birefringence of the fiber isB = 5.9 times 10^{-4}and the separation of the bending loss edges for the two polarization modes isDeltaupsilon = 0.51in the normalized frequency. The polarizing region can be tuned from 1.3 to 1.56 μm by varying the fiber-bending diameter from 3.5 to 4.5 cm. A 1.5-m length of polarizing fiber exhibits extinction ratios of 44.9 and 44.4 dB with insertion losses for the guided mode of 0.25 and 0.41 dB at 1.3 and 1.56 μm, respectively.  相似文献   
118.
The surgical treatment for truncal valve regurgitation is still controversial in patients with truncus arteriosus. A two-year-old girl with complaints of low weight gain and tachypnea was referred for treatment of truncal valve regurgitation. She had undergone an emergency pulmonary artery banding for severe congestive heart failure due to truncus arteriosus-type I at six months of age. This anomaly had been corrected by Barbero-Marcial method at seven months of age. But the truncal valve regurgitation started appearing at sixteen months of age with the progression of the stenosis of the pulmonary artery orifice and the right ventricular outflow tract regurgitation. Echo cardiography and cineangiography revealed the truncal valve to be bicuspid, and the regurgitation severe, especially through the prolapsed left sided cusp. The truncal valve was repaired by commissural suspension method, and the right ventricular outflow tract reconstructed with patch angioplasty of the pulmonary artery orifice and Carpentier-Edwards pericardial Bioprosthesis (19 mm). The post-operative course was uneventful. One year after, truncal valve regurgitation is small by color Doppler study. We conclude that valvoplasty is to be considered as the first choice of treatment for truncal valve regurgitation.  相似文献   
119.
A preform dimension control technique in the VAD process has been developed using chemical dry etching with fluoride gas applied to silica glass particles in an oxyhydrogen flame. Wholly synthesised VAD single-mode fibre preforms have been fabricated using this technique with high adjustment accuracy of outer/core diameter ratio. These preforms have exhibited excellent structural characteristics.  相似文献   
120.
We have analyzed the evolution of recognition of tRNAsSerby seryl-tRNA synthetases, and compared it to other type 2 tRNAs, which contain a long extra arm. In Eubacteria and chloroplasts this type of tRNA is restricted to three families: tRNALeu, tRNASer and tRNATyr. tRNALeuand tRNASer also carry a long extra arm in Archaea, Eukarya and all organelles with the exception of animal mitochondria. In contrast, the long extra arm of tRNATyr is far less conserved: it was drastically shortened after the separation of Archaea and Eukarya from Eubacteria, and it is also truncated in animal mitochondria. The high degree of phylo-genetic divergence in the length of tRNA variable arms, which are recognized by both class I and class II aminoacyl-tRNA synthetases, makes type 2 tRNA recognition an ideal system with which to study how tRNA discrimination may have evolved in tandem with the evolution of other components of the translation machinery.  相似文献   
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