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51.
The influence of humidity on the transmission loss of ZrF4-based optical fibres is clarified. Humidity increases the OH absorption loss as well as the scattering loss in the fibre. The absorption loss at 2.8 μm, due to fundamental stretching vibration of OH ions, has been reduced to 30 dB/km. It is foreseen that fluoride optical fibre with low loss at the 2–4 μm band can be realized by the extremely dry atmosphere process.  相似文献   
52.
The gain characteristics of a 1.4-μm-band thulium-holmium-doped ZBLYAN fiber amplifier are described. Signal gain is obtained over the whole 1.4-μm band for a pump power level of 73.5 mW. A maximum signal gain of 18 dB is achieved at a signal wavelength of 6.46 μm for a pump power of 150 mW at 0.79 μm. The noise figure is 5.6 dB in the signal wavelength region from 1.45-1.50 μm. From a comparison of the gain characteristics of thulium-holmium-doped ZBLYAN fibers and thulium-doped ZBLYAN fibers, it is proved that holmium ions play an effective role in increasing the gain and widening the gain spectrum  相似文献   
53.
54.
The distribution of the neuromedin K receptor (NK3; NKR) in the central nervous system was investigated in the adult rat by using in situ hybridization and immunohistochemical techniques. The rabbit anti-NKR antibody was raised against a bacterial fusion protein containing a C-terminal portion of NKR and affinity purified with a Sepharose 4B column conjugated to the fusion protein. Immunoblot analysis was performed to test the reactivity and specificity of the antibody. Crude membrane was prepared from cDNA-transfected Chinese hamster ovary (CHO) cells expressing each of the rat NKR, substance P receptor (NK1; SPR), and substance K receptor (NK2; SKR) and from the hypothalamus, cerebral cortex, and cerebellum. Immunoreactive bands were observed specifically in the NKR-CHO cells, hypothalamus, and cerebral cortex but not in the SPR- or SKR-CHO cells, nor in the cerebellum. Molecular weights of the immunoreactive bands ranged from 73 to 89 kDa and from 59 to 83 kDa in the NKR-CHO cells and tissues, respectively. The distribution of NKR-like immunoreactivity coincided with that of NKR mRNA. The expression of NKR was indicated on neuronal cell bodies and dendrites. NKR was found to be expressed intensely or moderately in neurons in the glomerular and granule cell layers of the main olfactory bulb; glomerular and mitral cell layers of the accessory olfactory bulb; layers IV and V of the cerebral neocortex; medial septal nucleus; nucleus of the diagonal band; bed nucleus of the stria terminalis; globus pallidus; ventral pallidum; paraventricular nucleus; supraoptic nucleus; zona incerta; dorsal, lateral, and posterior hypothalamic areas; amygdaloid nuclei; medial habenular nucleus; ventral tegmental area; midbrain periaqueductal gray; interpeduncular nuclei; substantia nigra pars compacta; linear, median, dorsal, and pontine raphe nuclei; posteromedial tegmental nucleus; sphenoid nucleus; nucleus of the solitary tract; intermediate and rostroventrolateral reticular nuclei; and lamina II of the caudal spinal trigeminal nucleus and spinal dorsal horn. These findings are discussed in relation to the physiological functions associated with neuromedin K.  相似文献   
55.
Excess noise peaks in an index-guided single-mode laser can be suppressed by superposing high-frequency current. By this method, index-guided lasers have stable noise characteristics and the noise level is about 7?12 dB lower than that in gain-guided multimode lasers at output power of about 3 to 5 mW.  相似文献   
56.
For quantitative evaluation of the regional lung function in patients with interstitial pulmonary disease (IP) in the sitting position, 99mTc-Technegas and 99mTc-macroaggregated albumin (MAA) single-photon emission tomography (SPET) studies were performed in 12 healthy controls (HC) and 42 IP patients. Four transverse images were prepared from the data obtained and designated as slices no. 1-4 from the top downward. Regions of interest (ROIs) were determined in the anterior and posterior parts of the lung in each slice, and the ratio of the count per voxel in the ROIs to the count in the entire lung was calculated as the regional Technegas index (T). The regional perfusion index (Q) was calculated by a similar procedure using the data of 99mTc-MAA SPET. The ratios between T and Q (T/Q) in the anterior and posterior regions of the lung, and the ratios of T and Q between the anterior and posterior regions of the lung (Tp/Ta and Qp/Qa) were examined. In the HC group, T/Q decreased but Tp/Ta and Qp/Qa increased from the upper to the lower lung fields. When IP patients were classified into (I) those in whom T/Q decreased from the upper to the lower lung fields, (II) those in whom it was similar in all slices, (III) those in whom it increased from slice 3 to slice 4, and (IV) those in whom it increased from slice 2 to slices 3 and 4, this classification was more closely correlated with %VC than with %DLCO or PaO2. When the patients were classified according to Tp/Ta and Qp/Qa into (A) those in whom the values were greater in the lower than the upper lung field, (B) those in whom the values were similar in all slices, and (C) those in whom the values were smaller in lower than in upper lung fields, categories B and C were observed frequently even in patients whose %VC was in the normal range. This method is considered to be an effective means to evaluate the progression and pathology of IP and to detect early impairment of lung function.  相似文献   
57.
Human prostatic carcinoma frequently metastasizes to bone tissue and activates bone metabolism, especially bone formation, at the site of metastasis. It has been reported that an extract of prostatic carcinoma and conditioned medium (CM) of a human prostatic carcinoma cell line, PC-3, established from a bone metastastic lesion, stimulate osteoblastic cell proliferation. However, there is little information about the effect of PC-3 CM on the differentiation of osteoblastic cells. In this study, we investigated the effect of PC-3 CM on the differentiation of two types of osteoblastic cells, primary fetal rat calvaria (RC) cells containing many undifferentiated osteoprogenitor cells, and ROS 17/2.8, a well-differentiated rat osteosarcoma cell line. PC-3 CM inhibited bone nodule formation and the activity of alkaline phosphatase (ALPase), an osteoblastic marker enzyme, on days 7, 14, and 21 (RC cells) or 3, 6, and 9 (ROS 17/2.8 cells) in a dose-dependent manner (5-30% CM). However, the CM did not affect cell proliferation or cell viability. PC-3 CM was found to markedly block the gene expression of ALPase and osteocalcin (OCN) mRNAs but had no effect on the mRNA expression of osteopontin (OPN), the latter two being noncollagenous proteins related to bone matrix mineralization. These findings suggest that PC-3 CM contains a factor that inhibits osteoblastic cell differentiation and that this factor may be involved in the process of bone metastasis from prostatic carcinoma.  相似文献   
58.
The pathogenesis associated with the 36 Megadalton (Md) plasmid of Salmonella choleraesuis subsp. choleraesuis serovar Enteritidis (S. Enteritidis) was assessed by using the plasmid-containing strain AL1190, plasmid-cured strain AL1192, and plasmid-reintroduced strain AL1193. After oral inoculation of strain AL1190 or AL1192 to C57BL/6 mice, mesenteric lymph nodes, spleens, and livers were examined for the numbers of viable bacteria and for the histopathological changes. The numbers of bacteria were greater and histopathological changes were severer in these organs of mice inoculated with strain AL1190, than in those with strain AL1192. Strains AL1190, AL1192, and AL1193 showed the equivalent survival rate to sera of guinea pig, calf, and pig, and grew equally well under the iron-limiting conditions. These results suggested that the 36 Md plasmid of S. Enteritidis contribute to the spread of the infection beyond small intestines to mesenteric lymph nodes, spleens, and livers, but not to serum resistance or acquisition of iron.  相似文献   
59.
A cryogenic loading system for introducing H(2) and D(2) into the diamond anvil cell has been designed and constructed. The integration of pressure loading mechanism, ruby fluorescence spectrometer, and microscope camera allows for in situ tuning and calibrating the pressure. The performance of the system has been demonstrated by successful synthesis of hydride and deuteride of transition metal and rare earth metal. Our cryogenic methodology features facile start-over of loading and in situ electrical resistance measurement of as-synthesized sample.  相似文献   
60.
The improvement of adhesion characteristics is very important for electric trains. The drive system of electric trains must have fine anti‐slip and anti‐skid readhesion controls. In order to achieve the required adhesion, we have already proposed an anti‐slip/skid readhesion control system based on disturbance observer and sensorless vector control. Moreover, we have already applied the proposed method to actual electric multiple unit trains Series 205‐5000. In this paper, using the experimental results of Series 205‐5000 and the numerical simulation results, we evaluate the proposed anti‐slip/skid readhesion control system and confirm that the system has the desired driving wheel torque response. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(4): 55–64, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20834  相似文献   
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