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Lee C.-R.,National Cheng Kung University | Lin S.-H.,National Cheng Kung University | Guo J.-W.,National Cheng Kung University | Lin J.-D.,National Cheng Kung University | And 6 more authors.
Optical Materials Express | Year: 2015

This paper reports for the first time an electrically and thermally controllable nanoparticle (NP) random laser in a well-aligned dye-doped liquid crystal (DDLC) cell. Experimental results show that the random lasing emission is attributed to the amplification of the fluorescence via the multiple scattering of the randomly distributed NPs in the diffusion rout of the well-aligned DDLC cell. The random laser can be electrically and thermally controlled by varying the applied voltage and cell temperature, respectively. As the applied voltage is increased, the orientational change of the LCs from homogeneous to homeotropic texture decreases the dye absorption and thus the spontaneous fluorescence emission, resulting in the decrease of the random lasing emission. The random lasing intensity decreases with increasing temperature at the nematic phase and dramatically increases after the nematic→isotropic (N→I) phase transition. The result in the former stage is attributed to the decreases in the absorption and thus in the spontaneous fluorescence emission for the laser dyes because of the decrease in the order of the laser dyes with increasing temperature at the nematic phase. The result in the latter stage results from the significant decrease of the loss because of the disappearance for the strong leakage of the scattering fluorescence light through the boundaries of the LCs and the glass substrates after the N→I phase transition. Moreover, the anisotropy of the random lasing is crucially determined by two factors: the anisotropies in the spontaneous emission and the leakage of the scattering fluorescence light. © 2015 Optical Society of America. Source


Horng C.-T.,Medical Education Center | Horng C.-T.,Tajen University | Horng C.-T.,Chung Shang Medical University and Chung Shang Medical University Hospital | Hsieh Y.-S.,Chung Shang Medical University and Chung Shang Medical University Hospital | And 8 more authors.
International Journal of Environmental Research and Public Health | Year: 2015

The effect of horizontal acceleration on human visual acuity and stereopsis is demonstrated in this study. Twenty participants (mean age 22.6 years) were enrolled in the experiment. Acceleration from two different directions was performed at the Taiwan High-Speed Rail Laboratory. Gx and Gy (< and >0.1 g) were produced on an accelerating platform where the subjects stood. The visual acuity and stereopsis of the right eye were measured before and during the acceleration. Acceleration <0.1 g in the X- or Y-axis did not affect dynamic vision and stereopsis. Vision decreased (mean from 0.02 logMAR to 0.25 logMAR) and stereopsis declined significantly (mean from 40 s to 60.2 s of arc) when Gx > 0.1 g. Visual acuity worsened (mean from 0.02 logMAR to 0.19 logMAR) and poor stereopsis was noted (mean from 40 s to 50.2 s of arc) when Gy > 0.1 g. The effect of acceleration from the X-axis on the visual system was higher than that from the Y-axis. During acceleration, most subjects complained of ocular strain when reading. To our knowledge, this study is the first to report the exact levels of visual function loss during Gx and Gy. © 2015 by the authors; licensee MDPI, Basel, Switzerland. Source


Lee C.-R.,National Cheng Kung University | Lin J.-D.,National Cheng Kung University | Mo T.-S.,Tainan University of Technology | Horng C.-T.,Kaohsiung Armed Forced General Hospital | And 2 more authors.
Optics Express | Year: 2015

This work investigates the performance evolution of color cone lasing emissions (CCLEs) based on dye-doped cholesteric liquid crystal (DDCLC) cells at different fabrication conditions. Experimental results show that the energy threshold (Eth) and relative slope efficiency (ηs) of the lasing signal emitted at each cone angle (0°-35°) in the CCLE decreases and increases, respectively, when the waiting time in a homogenously rubbed aligned DDCLC cell is increased from 0 hr to 216 hr (9 days). This result occurs because defect lines gradually shrink with the anchoring of the surface alignment when the waiting time is increased. Hence, the scattering loss decreases, and the dwelling time of the fluorescence photons in the resonator increases, which in turn enhances the CCLE performance. With the aligned cell given the pretreatment of a rapid annealing processing (RAP), the waiting time for obtaining an optimum CCLE can markedly be reduced sixfold. The surface alignment of the DDCLC cell also plays a necessary role in generating the CCLE. This work provides an insight into the temporal evolution of the performance for the CCLE laser and offers a method (RAP) of significantly speeding up the formation of a CCLE laser with optimum performance. © 2015 Optical Society of America. Source


Lin S.-M.,National Defense Medical Center | Liang J.-B.,National Defense Medical Center | Chien K.-H.,National Defense Medical Center | Chen Y.-H.,National Defense Medical Center | And 4 more authors.
Life Science Journal | Year: 2014

Purpose: To report a case of asymptomatic Wilson's disease (WD) in which the identification of a Kayser-Fleischer (K-F) ring and its characterization by confocal biomicroscopy led to the diagnosis. Methods: Case report. Results: Confocal biomicroscopy showed clustered, highly reflective, and round foci in Descemet's membrane, which we believed to be depositions of copper in this patient with asymptomatic WD. Conclusion: WD is characterized by toxic copper accumulation that can result in irreversible organ damage, neurologic deficit, and even death. Patients concurrent WD and hepatitis B show aggregate manifestations and worse prognosis than those of patients with WD alone. Hence, early diagnosis and treatment of WD are important in populations with high hepatitis B prevalence. The presence of a K-F ring is a pathognomonic sign of WD but is often confused as a sign of another disease such as corneal dystrophy or toxic or metabolic disorder. Early use of confocal biomicroscopy prior to a traditional serum test, urine assay, and liver biopsy may provide a fast, accurate, and non-invasive method to detect WD and potentially save a patient's life. Source


Chen W.-Y.,National Chung Hsing University | Huang Y.-C.,National Taichung University of Science and Technology | Yang M.-L.,Chung Shan Medical University | Lee C.-Y.,Chung Shan Medical University | And 7 more authors.
International Immunopharmacology | Year: 2014

Lipopolysaccharide (LPS), also called endotoxin, is the important pathogen of acute lung injury (ALI), which is a clinical syndrome that still lacks effective therapeutic medicine. Rutin belongs to vitamin P and possesses various beneficial effects. In this study, we investigate the potential protective effects and the mechanisms of rutin on LPS-induced ALI. Pre-administration with rutin inhibited LPS-induced arterial blood gas exchange and neutrophils infiltration in the lungs. LPS-induced expression of macrophage inflammatory protein (MIP)-2 and activation of matrix metalloproteinase (MMP)-9 were suppressed by rutin. In addition, the inhibitory concentration of rutin on phosphorylation of Akt was similar as MIP-2 expression and MMP-9 activation. In conclusion, rutin is a potential protective agent for ALI via suppressing the blood gas exchange and neutrophil infiltration. The mechanism of rutin is down-regulation of MIP-2 expression and MMP-9 activation through inhibition of Akt phosphorylation. © 2014 Elsevier B.V. Source

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