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101.
In this study, we report the growth of ZnO nanowire on quartz glass substrates with Au-catalyst assistance by electric current heating of ZnO ceramic bar. The effect of substrate temperature on the properties of ZnO nanostructures has been investigated systematically. Structural analysis indicates that the grown ZnO crystals belong to hexagonal phase with preferential growth along (0 0 2) orientation. Scanning electron microscopic studies reveal the aligned ZnO nanowires were grown at 800 °C. The typical length and diameter of nanowires are in the uniform ranges of 4–20 μm and 20–100 nm, respectively, showing their high aspect ratio of about 1000. We have made an attempt to discuss about the change in ZnO nanostructures with different substrate temperatures and the possible mechanism for the growth of nanowires. Optical reflectance studies show the infrared reflectivity was controlled through the substrate temperature.  相似文献   
102.
Although a loss-of-function mutation has been identified in familial Parkinson’s disease PARK7, the wild-type of DJ-1 is known to act as an oxidative stress sensor in neuronal cells. Recently, we identified UCP0045037 as a compound that bound to the reduced form of DJ-1 by in silico virtual screening. In this study, we determined the neuroprotective effects of UCP0045037 against focal cerebral ischemia-induced neurodegeneration in rats. Hydrogen peroxide-induced cell death was significantly inhibited by UCP0045037 in both rat mesencephalic dopaminergic neurons and human normal SH-SY5Y cells. In contrast, DJ-1-knockdown SH-SY5Y cells lost the protective activity of UCP0045037. These results suggest that UCP0045037 interacts with endogenous DJ-1 and produces a neuroprotective response.  相似文献   
103.
Life cycle engineering (LCE) is a key concept for promoting environmentally sustainable practices among manufacturing firms. A major hurdle in the implementation of LCE is the lack of a systematic and strategic method to design or plan an entire product life cycle. To address this issue, this keynote provides a framework for life cycle development and proposes the concept of life cycle planning. This paper aims to provide explicit and systematic methodologies for life cycle planning by reviewing this research area. Practical cases that employ life cycle planning are also illustrated. Finally, some research directions are suggested.  相似文献   
104.
The present study investigates experimentally the effects of thermal properties of the hot surface and droplet characteristics on the droplet evaporation. Cylindrical blocks made of Stainless Steel, Aluminum and Brass with different degrees of surface roughness were used. The droplet diameter and velocity were controlled independently. The behavior of droplet during the collision with hot surface was observed with a high-speed camera. The results presented the effect of the thermal properties of the hot surface, droplet Weber number, droplet velocity, droplet size, hot surface conditions; surface superheat and degree of surface roughness on the solid–liquid contact time and the maximum spread of droplet over the surface. Empirical correlations have been deduced describing the relationship between the hydrodynamic characteristics of an individual droplet impinging on a heated surface and concealing the affecting parameters in such process. Also, the comparison between the current results and the results due to others investigators shows good agreement in which the difference between them ranged from 5% to 25%.  相似文献   
105.
The field orientation control of current source inverter (CSI) drive induction motor (IM) systems has been known to give an induction motor dc motorlike characteristics. As a result of an analysis, the characteristic of these systems does not necessarily coincide with that of dc motor systems, especially with light loads. The result of the analysis is verified by experiments.  相似文献   
106.
A signal current from a cylindrical ionisation chamber with an ionisation volume of 62.7 cm3, 40 mm in diameter and 50 mm long, peaked when the chamber was lixed at 0 degrees and at 90 degrees in 137Cs and 60Co gamma ray fields for source-chamber distances of 1 m and 2 m. A smaller ionisation chamber showed a small peak at 0 degrees in both fields but not at 90 degrees. However, calculations indicated that the signal current from the smaller chamber would also show a peak at 90 degrees in a 137Cs point-source gamma ray field. Peaks occur because gamma rays attenuate along the cylindrical side wall or along the end walls when a chamber is tilted slightly from 0 degrees or 90 degrees and the direction of the gamma ray beam agrees with the plane of one of these walls. These facts suggest the need for care in the common practice of measuring and calculating responses for cylindrical ionisation chambers fixed perpendicular to gamma ray beams.  相似文献   
107.
Using two hexagonal samples of ice, polycrystalline and single-crystalline, the electrical treeing has been investigated under an applied impulse voltage. The crystallinity and temperature of the ice play an important role in the events of the treeing. In the single-crystalline ice, the tree in the samples at -25 /spl deg/C always progressed along the basal plane of the ice crystal, but at -196 /spl deg/C, it progressed along the c-axis. These distinctive patterns of the tree progression were attributed to the crystal axis dependence on the electrical conductivity and the relative permittivity at each temperature. The current accompanying the trees were detected by means of an electro-optic coupling with light emitting diodes and photodiodes. After the large current pulses which occur just after voltage application, small intermittent current pulses were visible in the wave tail of the applied voltage. These intermittent pulses appear to generate by the movement of accumulated charges after the formation of tree channels. The electrical breakdown strength of ice at -25 C was large for the electric field parallel to the c-axis of the single-crystalline ice.  相似文献   
108.
Local excision of 67 pulmonary lesions in 5 patients was performed with the Nd-YAG laser. There were 2 women and 3 men with an average age of 68 years. The patients consisted of three cases of metastatic lung cancer (65 lesions), one hamartoma (One lesion) and one organized pneumonitis (one lesion). The lesion was first enucleated by a contact method using an Nd-YAG laser scalpel, then the crater of the resected lesion in the normal lung tissue was coagulated with a defocused laser beam. The craters of 52 of the 67 resected lesions which were shallow seated in the lung were left open, but the other 15 resected lesions were closed with sutures. Total blood loss was less than 100 ml. There was no bleeding or air leakage (30 cm water pressure) during the post operative days in 4 of the 5 patients, but one patients (one lesion) had to be treated by bronchoscopic endobronchial embolization against a persistent air leak. This lesion was 2.5 cm in diameter and 4 cm deep in the lung on CT. The other lesions were also measured by CT. The tumor size was 1.4 +/- 0.7 cm and the depth was 2.4 +/- 1.0 cm. The Nd-YAG laser is very suitable for local resection of peripheral lung lesions without suturing.  相似文献   
109.
The clinical efficacy and safety of a beta 2-microglobulin (beta 2M) adsorbent column, BM-01, on the treatment of dialysis-related amyloidosis were investigated in 7 hemodialysis patients for more than 6 months. The percent reduction of serum beta 2M was more than 60-70%, and the level at the end of each session was less than 10 mg/L in almost all patients. The amount of beta 2M removed was calculated as more than 200-300 mg/session. The results demonstrated that BM-01 performed very well for removing beta 2M, was capable of maintaining less than 25 mg/L of time average concentration (TAC) for beta 2M, and improved the clinical symptoms. Clinically severe side effects were not observed. We recommend that BM-01 should undergo further evaluation for its usefulness in the long-term treatment of dialysis-related amyloidosis, though treatment with the column may not be successful in preventing the onset of the disease.  相似文献   
110.
Proteins associated with the mineral phase of dentin are considered to have the potential to alter cell function within the local environment, during development and regeneration of tooth/periodontal tissues. Cells that may be altered include osteoblasts, ameloblasts, periodontal ligament cells, odontoblasts, and cementoblasts. However, specific factors within dentin controlling cell activity have not been elucidated. To investigate further the role of dentin proteins in regulating cell behavior, MC3T3-E1 cells, a mouse osteoprogenitor cell line, were exposed to guanidine/EDTA extracts of dentin (G/E-D) prepared from bovine teeth. Cells, with or without G/E-D (2 to 50 microg/ml), were evaluated for proliferative activity and for mRNA expression of bone-associated genes. Results indicated that G/E-D suppressed cell proliferation and caused striking morphological changes, including the conversion of cuboidal cells into fibroblastic, spindle-shaped cells. Markers of osteoblast differentiation, osteocalcin and bone sialoprotein mRNA were decreased, while osteopontin mRNA was enhanced in cells exposed to G/E-D. Since transforming growth factor beta (TGFbeta1) has been reported to influence cells in a similar fashion, G/E-D were examined for the presence of and concentration of TGFbeta using slot blot analysis and enzyme immunoassay (ELISA), respectively. These analyses demonstrated that G/E-D contained 6.6 ng/mg of TGFbeta1. Next, cells were exposed to G/E-D in conjunction with anti-TGFbeta1,2,3 antibody. When cells were exposed to antibody, G/E-D-mediated changes in morphology and gene expression were blocked. These results suggest that TGFbeta1 and perhaps other factors in dentin can regulate cell behavior and, therefore, can influence development, remodeling, and regeneration of mineralized tissues.  相似文献   
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