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11.
The effects of estrogen-induced hyperlipidemia on plasma lipid peroxidation, fatty acid composition and osmotic fragility of erythrocytes in chickens were studied. Young male chickens implanted with estrogen for three wk developed a marked hyperlipidemia. Plasma levels of triglyceride, cholesterol and phospholipid were elevated 68-, four- and 24-fold, respectively, over controls. There was also a two-fold increase in plasma lipid peroxidation measured by the thiobarbituric acid test. Vitamin E supplement (1,000 IU/kg diet) reduced the plasma lipid peroxidation to the control level, but had no effect on the plasma lipid content. Estrogen-induced hyperlipidemia resulted in changes in the fatty acid composition of membrane lipids of erythrocytes. The major changes were an increase in oleic acid from 10.0% to 14.2% and a decrease in linoleic acid from 31.3% to 26.0%. The erytrocytes with an altered membrane fatty acid composition were found to have an increased osmotic fragility. It was apparent that there was a direct correlation between the oleic acid content and the osmotic fragility of erythrocytes.  相似文献   
12.
Color segmentation takes a great attention because color is an effective and robust visual cue for characterizing an object from the others. However, color segmentation suffers from color variations incurred by irregular illumination changes. We propose a reliable color modeling approach in hue–saturation–intensity (HSI) color space while considering intensity information by adopting the B-spline curve fitting to make a mathematical model for statistical characteristics of a color with respect to intensity. It is based on the fact that color distribution of a single-colored object is not invariant with respect to brightness variations even in the HS (hue–saturation) plane. The statistical characteristics contain the mean and standard deviation of hue and saturation with respect to intensity. They are mathematically expressed as four bar graphs. In order to fit the bar graphs to continuous curves, we use B-spline curve fitting procedure. From several experimental results, we verify that the proposed algorithm is successfully applied to color segmentation under various illumination conditions.  相似文献   
13.
14.
Lim TK  Jeong MY  Song C  Kim DC 《Applied optics》1998,37(13):2723-2728
The effect of light absorption by sample in the analysis of Makerfringe data for estimating a second-order nonlinear coefficient hasbeen studied experimentally. Two theories, one by Jerphagnon andKurtz that neglects the absorption effect and one by Herman and Haydenthat takes into account the absorption effect, were compared with theexperimental results. It was found that Jerphagnon and Kurtz'sformula was unable to predict correctly not only the magnitude but alsothe incident angle dependence or the sample thickness dependence of thesecond harmonic signal generated by the sample with strong absorption, whereas the theory by Herman and Hayden was able to make thosepredictions fairly well. It was also found that the error in theestimated nonlinear coefficient when one uses Jerphagnon and Kurtz'sformula could be as large as 2-4 times the true value, depending onsample thickness.  相似文献   
15.
Tissue dynamics spectroscopy combines dynamic light scattering with short-coherence digital holography to capture intracellular motion inside multicellular tumor spheroid tissue models. The cellular mechanical activity becomes an endogenous imaging contrast agent for motility contrast imaging. Fluctuation spectroscopy is performed on dynamic speckle from the proliferating shell and hypoxic core to generate drug-response spectrograms that are frequency versus time representations of the changes in spectral content induced by an applied compound or an environmental perturbation. A combination of 28 reference compounds and conditions applied to rat osteogenic UMR-106 spheroids generated spectrograms that were crosscorrelated in a similarity matrix used for unsupervised hierarchical clustering of similar compound responses. This work establishes the feasibility of tissue dynamics spectroscopy for three-dimensional tissue-based phenotypic profiling of drug response as a fully endogenous probe of the response of tissue to reference compounds.  相似文献   
16.
Abstract— Non‐volatile memory effects of an all‐solution‐processed oxide thin‐film transistor (TFT) with ZnO nanoparticles (NPs) as the charge‐trapping layer are reported. The device was fabricated by using a soluble MgInZnO active channel on a ZrHfOx gate dielectric. ZnO NPs were used as the charge‐trapping site at the gate‐insulator—channel interface, and Al was used for source and drain electrodes. Transfer characteristics of the device showed a large clockwise hysteresis, which can be used to demonstrate its memory function due to electron trapping in the ZnO NP charge‐trapping layer. This memory effect has the potential to be utilized as a memory application on displays and disposable electronics.  相似文献   
17.
Abstract— Even though dyes have a fine resolution and good chromaticities, they are not widely used as coloring materials for color filters (CFs) due to their low thermal stability and chemical resistance. A series of azo‐dye derivatives, which consist of two cross‐linkable acrylate or methacrylate groups to improve thermal and chemical properties, have been synthesized and used to fabricate color filters. The spectral properties and chemical/thermal stabilities of the fabricated CFs were investigated by comparing dye‐based CFs, without a complicated dispersion process, but with pigment‐based CFs using dispersed pigment. Also, more properties including the development test and surface morphologies lithographic properties were studied. The synthesized azo dyes were characterized by elemental analysis, UV‐visible spectra, IR, mass, and 1H‐NMR spectra.  相似文献   
18.
We consider a problem of finding a path of an unmanned combat vehicle that patrols a given area by visiting a given set of checkpoints with the objective of minimizing possibility of enemy’s infiltration. In this study, we focus on a situation in which the possibility of enemy’s infiltration at (through) each checkpoint is increased nonlinearly as time passes and the checkpoint may be patrolled multiple times during a planning horizon. We develop two-phase heuristics in which an initial path is constructed in the first phase and then it is improved in the second phase. For evaluation of the performance of the proposed heuristics, computational experiments are performed on randomly generated problem instances, and results show that the heuristics give good solutions in a reasonably short time.  相似文献   
19.
A detachable thermosiphon, as a transient thermal switch for conduction-cooled superconducting magnet, is designed, fabricated and tested. A thermosiphon between the first and second stages of a cryocooler can reduce the cool-down time of a conduction-cooled superconducting magnet by using the large cooling capacity of the first stage. The thermosiphon is a very efficient heat transfer device until all the working fluid in it freezes (off-state). After the working fluid freezes and the second stage temperature becomes lower than that of the first stage, however, the thermosiphon then becomes a conduction heat leak path between two stages of the cryocooler. Considering a very small cooling capacity of the second stage of the cryocooler around 4.2 K, the conduction heat loss is not negligible. Therefore, a detachable thermosiphon, made of a metal bellows, is considered to be able to eliminate such a conduction heat leak. The mock-up magnet is cooled down with the thermosiphon and the thermodynamic states of the thermosiphon and the mock-up magnet are precisely examined during the whole cool-down process. At off-state, the thermosiphon is detached mechanically from the magnet. In this way, the conduction heat leak path through the thermosiphon wall is completely eliminated. This paper describes the detailed transient operation of the detachable thermosiphon using nitrogen as the working fluid.  相似文献   
20.
Wire ball open failure at the interface of the gold wire and bonding pad of a multi-stack package (MSP) under high temperature storage (HTS) condition of 150 °C is studied. Failure analysis using FIB-SEM was conducted by in-plane moiré interferometry and FEA to clarify the failure mechanism. The ball open failure due to Kirkendall void that results from metal diffusion at high temperature was accelerated by the tensile stress imposed at the gold wire. The tensile stress developed at the gold wire when packages showing different warpage behaviours were stacked. Mechanical interaction between top and bottom packages caused unstable warpage, readily twisted and saddled. The wire came in contact with the photo-sensitive solder resist (PSR) dam because of the unstable warpage and this contact resulted in tensile stress at the gold wires. Solder flux residues reacted with the encapsulant, and as a result, the encapsulant of the top package adhered to the chip of the bottom package, and this adherence created additional tensile stress at the gold wires. To reduce the tensile stress at the wires, the PSR dam was removed, loop shape was altered from 45° to 90°, water soluble flux was applied, and cleaning process was added. HTS reliability was significantly improved and guaranteed after reducing the tensile stress at the wires.  相似文献   
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