Self-Heating-Induced Deterioration of Electromechanical Performance in Polymer-Supported Metal Films for Flexible Electronics.

The retention of electrical performance under the combined conditions of mechanical strain and an electrical current is essential for flexible electronics. Here, we report that even below the critical current density required for electromigration, the electrical current can significantly deteriorate the electromechanical performance of metal film/polymer substrate systems. This leads to a loss of stretchability, and this effect becomes more severe with increasing strain as well as increasing current. The local increase of electrical resistance in the metal film caused by damage, such as localized deformations, cracks, etc., locally raises the temperature of the test sample via Joule heating. This weakens the deformation resistance of the polymer substrate, accelerating the necking instability, and consequently leading to a rapid loss of electrical conductivity with strain. To minimize such a current-induced deterioration of the polymer-supported metal films, we develop and demonstrate the feasibility of two methods that enhance the deformation resistance of the polymer substrate at elevated temperatures: increasing the thickness of the polymer substrate, and utilizing a polymer substrate with a high glass transition temperature.

Color Fringe Correction by the Color Difference Prediction Using the Logistic Function.

This paper proposes a new color fringe correction method that preserves the object color well by the color difference prediction using the logistic function. We observe two characteristics between normal edge (NE) and degraded edge (DE) due to color fringe: 1) the DE has relatively smaller R-G and B-G correlations than the NE and 2) the color difference in the NE can be fitted by the logistic function. The proposed method adjusts the color difference of the DE to the logistic function by maximizing the R-G and B-G correlations in the corrected color fringe image. The generalized logistic function with four parameters requires a high computational load to select the optimal parameters. In experiments, a one-parameter optimization can correct color fringe gracefully with a reduced computational load. Experimental results show that the proposed method restores well the original object color in the DE, whereas existing methods give monochromatic or distorted color.

Pulmonary cryptococcosis that mimicked rheumatoid nodule in rheumatoid arthritis lesion.

Recently, the incidence of pulmonary cryptococcosis is gradually increasing in rheumatoid arthritis (RA) patients. Pulmonary rheumatoid nodules (PRN) are rare manifestations of RA. Eighteen months ago, a 65-year old woman was admitted to hospital due to multiple nodules (2.5×2.1×2 cm) with cavitations in the right lower lobe. She was diagnosed with RA three year ago. She had been taking methotrexate, leflunomide, and triamcinolone. A video-assisted thoracoscopic surgery biopsy was performed and PRN was diagnosed. However, a newly growing huge opacity with cavitation was detected in the same site. Pulmonary cryptococcal infection was diagnosed through a transthoracic computed tomograpy guided needle biopsy. Cryptococcus antigen was detected in serum but not in cerebrospinal fluid. The patient was treated with oral fluconazole which resulted clinical improvement and regression of the nodule on a series of radiography. Herein, we report the case of pulmonary cryptococcosis occurring in the same location as that of the PRN.

Gender-specific molecular heterosis of dopamine D2 receptor gene (DRD2) for smoking in schizophrenia.

We examined the genetic effect of DRD2 A1 allele in 167 Korean schizophrenics in relation to their smoking habit. Although there was no apparent difference in the genotype distributions of DRD2 gene among the female schizophrenics (n = 66), the male counterpart (n = 101) showed significant differences in their genotype distributions. The comparison between male smoking and non-smoking patients showed the difference in genotype distribution (P = 0.010) with a higher prevalence of A1 allele (P = 0.020) and frequency of heterozygotes (P = 0.005), but not frequency of the A1 allele. The A1A2 heterozygotes male showed significantly higher smoking rate compared to the A1A1 or A2A2 homozygotes male, and non-smokers were deficient in heterozygotes. By contrast, among female schizophrenics, the heterozygotes showed a lower smoking rate than homozygotes and there were more heterozygotes in non-smokers. The deviation from Hardy-Weinberg expectations was observed in male and female non-smokers showing quite opposite profiles. Highly significant differences were seen between male and female non-smokers in A1 prevalence (P = 0.001), genotype distribution (P = 0.00011), and frequency of heterozygotes (P = 0.00003), but not in A1 frequency. The analyses from both male and female as one group showing no significant difference in the genotype distributions between smokers and non-smokers could be explained by the gender difference in the genetic effect of DRD2 A1 allele. Our findings present the gender-specific molecular heterosis of DRD2 gene in relation specifically to the smoking status of schizophrenic patients. They indicate the importance of heterosis and gender effects that should be taken into consideration for the association studies.