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1.
One of the anaphylatoxins, C5a, is known to increase the expression of the complement receptors, CR1 and CR3, on PMNs which play important roles in the phagocytosis. We measured the expression of these receptors before and after the stimulation with C5a and C5a-receptors (C5aR) on PMNs in patients with systemic lupus erythematosus (SLE). PMNs from 16 patients and 11 normal controls were tested. All the patients with SLE were administered with prednisolone orally and were in the inactive stage. The CR1 expression in SLE was significantly weak (p < 0.01) before and after stimulation with 4.55 nM (50 micrograms/ml) of C5a. There was no significant difference of CR3 expression before stimulation. However, after the stimulation with C5a, the increase of CR3 on PMNs from SLE was significantly small (p < 0.01). C5aR on PMNs showed no difference between the two groups. However, the expression of C5aR was significantly suppressed in patients treated with a high dosage of prednisolone (> = 10 mg/day) compared to those with a low dosage of prednisolone (< 10 mg/day). There was no significant difference of CR1 and CR3 expression between these groups. It is concluded that the increase of CR1 and CR3 on PMNs by C5a in small in SLE, of which impaired increase is not due to C5aR on PMNs, and that the expression of C5aR is suppressed by prednisolone.  相似文献   
2.
Infrared (IR) detecting elements were prepared using positive temperature coefficient (PTC) thermistors with large temperature coefficients of resistivity (α). Their compositions were denoted as Ba1−x Sr x Nb0.003Ti0.997O3 + 1 mol % TiO2 + 0.07 mol %MnO (x=0, 0.2), and their temperature coefficients of resistivity were 78 and 50% K−1, respectively. Their IR sensing properties were measured under the self-regulating heating conditions, and were compared with those of a detector with small α (18 % K−1). It was shown that large α was effective for controlling the element temperature by self-regulating heating and for improving sensitivity. The responsivity,R v of the element withx=0.2 was 980 VW−1, and was as large as those of pyroelectric detectors. Expressions which normalize the sensitivity and the thermal time constant were derived. From these expressions, criteria for improving some IR sensing properties were obtained.  相似文献   
3.
The sintering of fibrous BaTiO3 powder particles was investigated. Special emphasis was given to the role of particle orientation in the compact on densification and microstructure development. Compacts were made by dry-pressing. During the initial stage of sintering, the fibrous particles rearranged and bundles of particles were formed. The volume of pores between bundles of particles decreased on further heating. Grain growth started when the sintered density reached ca. 56% of the theoretical density. Higher temperatures of sintering increased the degree of the crystal axis orientation. Thus, highly orientated sintered bodies with high densities were prepared by heating at 1500 °C.  相似文献   
4.
In the current work, we prepared a TiO2 coating on stainless mesh using electrophoretic deposition (EPD), and applied voltage to a stainless mesh to examine the synergy effect on photocatalysis of both 1,4-dioxane and ethylene glycol diformate (EGDF), a main intermediate of the photocatalysis of 1,4-dioxane. The photocatalytic decomposition rate of 1,4-dioxane depends on applying voltage under diffusion-limited reaction conditions. Ethylene glycol diformate and 1,4-dioxane exhibited inverse voltage dependence. Voltage swing provides high-efficiency photocatalysis of 1,4-dioxane while suppressing EGDF formation. This method will be effective for a photocatalysis system containing several chemicals, each with different voltage dependence.  相似文献   
5.
Structural images of the stacking faults in β-SiC were obtained with a high-resolution electron microscope. Stacking faults initially present in β-SiC powder particles were eliminated as grain growth proceeded at elevated temperatures.  相似文献   
6.
The metastable β form of bismuth sesquioxide was obtained by doping antimony oxide. The solubility of antimony was 4 to 10 at. %in β specimens, where more than 75% of the antimony atoms were valenced at 5+.  相似文献   
7.

Epilepsy is a neurological disorder that may affect the autonomic nervous system (ANS) from 15 to 20 min before seizure onset, and disturbances of ANS affect R–R intervals (RRI) on an electrocardiogram (ECG). This study aims to develop a machine learning algorithm for predicting focal epileptic seizures by monitoring R–R interval (RRI) data in real time. The developed algorithm adopts a self-attentive autoencoder (SA-AE), which is a neural network for time-series data. The results of applying the developed seizure prediction algorithm to clinical data demonstrated that it functioned well in most patients; however, false positives (FPs) occurred in specific participants. In a future work, we will investigate the causes of FPs and optimize the developing seizure prediction algorithm to further improve performance using newly added clinical data.

  相似文献   
8.
TiO2 (anatase) coating was prepared on stainless mesh by electrophoretic (EPD) process utilizing an isopropyl alcohol (IPA)-based suspension with submicron TiO2 powder. When the deposition time was 30 s, a smooth thin coating was obtained. It remained crack-free even after sintering. Coating surface morphology was roughened by UV pre-illumination of the suspension. Photocatalytic decomposition of IPA to acetone and resultant electrochemical reaction at cathode during EPD provides heterogeneous deposition.  相似文献   
9.
The orientation and grain boundary microstructure of alumina in reactive metal penetration Al/Al2O3 composites are studied using orientation imaging microscopy and the results are compared with those of sintered polycrystalline Al2O3. The interconnected Al2O3 in the composite material is separated by Σ3 boundaries (twins) with a 60° rotation around the [0001] direction. A high frequency (∼100%) of Σ3 coincidence boundaries in composite alumina is remarkable since only ∼12% of boundaries in a sintered polycrystalline Al2O3 are of special nature. The coincidence boundaries in the in situ alumina grow in a coherent and faceted manner.  相似文献   
10.
Coefficients of friction were measured at elevated temperatures using a hot flat strip drawing test machine newly developed by the authors for the purpose of confirming the coefficients of friction used for the FEM simulation of hot stamping. To examine the functions of the tribo-simulator, the coefficients of friction are measured using hot rolling oil with an emulsion, which is supplied continuously, while varying the drawing speed, drawing pressure and temperature. From the experimental results, it was shown that the coefficient of friction in hot stamping can be measured using this tribo-simulator. The measured coefficients of friction can be used as values in the FEM simulation of hot stamping. Moreover, the tribological behavior at the interface between the die and strip in hot stamping can be evaluated from the coefficient of friction, because it is one of the quantitative values used to represent the tribological behavior between the die and blank.  相似文献   
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