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In this study, the effect of rheological properties of Cu nano/micro (NP/MP)-inks with various amounts of dispersant on the print-ability and sinter-ability for flash light sintering was investigated. The rheological properties such as viscosity, viscoelasticity and thixotropic index of Cu NP/MP-inks were measured using a rheometer. The fabricated Cu NP/MP-inks were printed on polyimide substrate using a screen printing method. The 3D profile of printed Cu NP/MP-ink pattern was measured using surface profiler. In order to sinter the printed Cu NP/MP-inks, flash light sintering technique was employed. The flash light irradiation conditions (pulse power, pulse number, on-time, and off-time) were optimized to obtain the high sintering characteristic of Cu NP/MP-inks. In order to characterize the microstructures and transformation crystal phase of the sintered Cu NP/MP-inks, scanning electron microscopy, focused ion-beam and X-ray diffraction analysis were performed. From the results, the optimal sintered Cu NP/MP-ink film had a 6.16 μΩ·cm resistivity and 5B level of adhesion strength.

Transparent conducting electrodes (TCEs) are fabricated through the flash light sintering of reverse-offset printed Ag mesh patterns. Interestingly, the narrower printing lines require a higher flash light energy to obtain an equivalent sheet resistance even if the same Ag nanoparticle ink is used. The microstructural development of sintered Ag nanoparticles is also retarded with the decrease of line width after the same flash light sintering. The temperature calculation in the Ag mesh patterns clearly reveals that heat dissipation is affected by the print dimension. To improve the performance of Ag mesh TCEs with 3 μm wide lines, a preheating step comprised of multi-pulses is inserted before a main flash light sintering. The multi-pulsed flash light sintering is effective in decreasing the sample temperature and in removing the substrate damages or microstructural defects. As a result, the flash light-sintered Ag mesh TCEs shows a sheet resistance of 27 Ω/□ and an optical transmittance of 84.7% including an optical transmittance of substrate.

In this study, an intense pulsed light (IPL) process for annealing an indium-gallium-zinc-oxide (IGZO) semiconductor was conducted via flash white light combined with near-infrared (NIR) and deep-ultraviolet (DUV) drying to form a thin-film transistor (TFT). The IGZO thin-film semiconductor was fabricated using a solution-based process on a doped-silicon wafer covered with silicon dioxide. In order to optimize the IPL irradiation condition for the annealing process, the flash white light irradiation energy was varied from 70 to 130 J/cm2. Drying by NIR and DUV irradiation was employed and optimized to improve the performance of the TFT during IPL annealing. A TFT with a bottom-gate and top-contact structure was formed by depositing an aluminum electrode on the source and drain on the IPL-annealed IGZO. The electrical transfer characteristic of the TFT was measured using a parameter analyzer. The field effect mobility of the saturation regime and on/off current ratio were evaluated. Changes of the metal-oxide bonds in the IGZO thin film were analyzed using X-ray photoelectron spectroscopy to verify the effect of NIR and DUV drying and IPL annealing. Also, the distributions of the carrier concentration on the IPL-annealed IGZO were measured through a hall-effect system to deeply investigate the transition of the electrical characteristic of the TFT. From the results, it was found that the bond between oxygen and the gallium compound was activated via DUV irradiation. The NIR- and DUV-assisted IPL-annealed IGZO-based TFT showed highly enhanced electrical performance with a 7.7 cm2/V·s mobility and a 3 × 106 on/off ratio.

Objective To observe the prognostic influences of the cardiac rehabilitation (CR) program in Korean acute myocardial infarction (AMI) patients during the first year after an occurrence of the disease. Method A total of 141 AMI patients who underwent percutaneous coronary intervention (PCI) were recruited consecutively for this study and divided into the CR group and the control group. The CR group completed the phase 2 CR program in the hospital for a period of 6-8 weeks and maintained self-exercise in their community by exercise prescription for a year after AMI. We performed a prospective comparison of the patients' demographic data, high sensitive C-reactive protein (hs-CRP) level after the 4-month CR program, and the rate of recurrence (AMI, re-hospitalization, positive coronary angiogram, needed revascularization procedure, or death) between the two groups. Results Compared to the control group (0.33±0.48 mg/dl), the hs-CRP level was lower in the CR group (0.18±0.32 mg/dl) after 4 months of exercise. The recurrence rate was lower (10%, 7/69) in the CR group, compared to the control group (24%, 17/72, p

OBJECTIVE To compare the technical strengths and weaknesses between retrodiscal (RD) and conventional subpedicular (SP) approaches of transforaminal epidural block (TF-EPB). METHOD Sixty-one patients with L5 radiculopathy who planned to undergo TF-EPB were consecutively enrolled as study subjects. Subjects were randomly assigned to one of two groups. For the RD approach, the positioning of the patient and the C-arm were similar to that for lumbar discography. We compared the pattern of dye spreads, the frequency of complications during the procedures, and the effect of the pain block 2 weeks after the procedure between the two groups. RESULTS For the RD group (n=24), the contrast dye diffused around the L5 and S1 nerve roots in 16 cases (67%), but it diffused around only the L5 root in 27 cases (73%) in the SP group (n=37) (p

Multilocus sequence typing (MLST) has been successfully applied to the epidemiology of Candida albicans isolates not only within the hospital setting but also in multiple locations nationwide. We performed MLST to investigate the genetic relatedness among bloodstream infection (BSI) isolates of C. albicans recovered from 10 Korean hospitals over a 12-month period. The 156 isolates yielded 112 unique diploid sequence types (DSTs). While 95 DSTs were each derived from a single isolate, 17 DSTs were shared by 61 isolates (39.1%). Interestingly, 111 (71.1%) isolates clustered within previously known clades, and 29 (18.6%) clustered within a new clade that includes strains of Asian origin previously typed as singletons. This MLST study was complemented by restriction endonuclease analysis of genomic DNA using BssHII (REAG-B) in order to evaluate whether strains with identical DSTs and originating from the same hospital corresponded to nosocomial clusters. Importantly, only those isolates with a strong epidemiological relationship showed ≥95% identical REAG-B types. Our results indicate that REAG-B typing can be complementary to MLST but should be limited to the investigation of isolates of identical DSTs and when interhuman transmission is suspected.

BACKGROUND Fluorescent dye Rhodamine 6G (R6G) is a substrate of multidrug resistance pumps and its accumulation is reduced in some azole-resistant Candida isolates with the upregulation of multidrug efflux transporter genes. Despite reports on species-specific differences in azole susceptibility in various Candida species, only a few studies have been reported on the R6G accumulation among clinical isolates of Candida species. In this study, we compared R6G accumulation between six different Candida species. METHODS The intracellular accumulation of R6G and minimal inhibitory concentrations (MICs) of three triazole agents were investigated in 48 strains of six Candida species (14 C. albicans, 9 C. tropicalis, 8 C. glabrata, 8 C. krusei, 7 C. parapsilosis, and 2 C. haemulonii). R6G accumulation was measured by using flow cytometry and the geometric mean of the fluorescence intensity (GMF) was used to compare the accumulation between the Candida isolates. RESULTS The GMF values for the C. tropicalis, C. albicans, C. krusei, C. parapsilosis, and C. glabrata isolates were 167.3+/-18.5, 126.9+/-6.6, 88.5+/-18.5, 50.8+/-7.0, and 38.1+/-3.9, respectively. C. glabrata had a significantly lower mean GMF than all the other Candida species (P

Objective To survey the cardiovascular complications induced by cardiac monitoring exercise during 10 years of our cardiac rehabilitation (CR) clinic and report on the safety of monitoring exercise training for early hospital-based CR. Method All cardiac patients who participated in our exercise program from January 2000 through December 2009 were recruited as study subjects. We stratified the exercise risks of cardiac events and conducted the monitoring exercise with individualized prescriptions. We measured all cardiac complications, including death, symptoms, abnormal hemodynamic responses, and electrocardiogram (ECG) abnormality during exercise training, for 10 years. A total of 975 patients (68% male; mean age, 58.9±10.6) were included in this study. Initial indications for CR were recent percutaneous transluminal coronary angioplasty (PTCA) (75%), post-cardiac surgery (coronary bypass graft, 13.2%), valvular surgery and other cardiac surgery (4.2%), and others (7.6%). Results The study population underwent 13,934 patient-hours of monitoring exercise. No death, cardiac arrest or acute myocardial infarction (AMI) occurred during exercise (0/13,934 exercise-hours). Fifty-nine patients experienced 70 cardiovascular events during the 13,934 exercise-hours (1/199 exercise-hours); there were 17 cases of angina only (1/820 exercise-hours), 31 cases of ECG abnormalities only (1/449 exercise-hours), 12 cases of angina with ECG abnormalities (1/1,161 exercise-hours), and 10 cases of abnormal hemodynamic responses (1/1,393 exercise-hours). Conclusion Early hospital-based CR is safe enough that no death, cardiac arrest or AMI occurred during the 13,934 patient-hours of monitoring exercise. However, risk stratification for exercise-induced cardiovascular events, proper exercise prescriptions, and intensive ECG monitoring are required prior to initiation of the monitoring exercise.

This study is the first attempt to search for the relationship between socioeconomic characteristics and year of immigration among Asian populations in the United States for the purpose of examining the feasibility of the ‘late arrival hypothesis’ that late arrival accounts for one's low socioeconomic status at the place of destination. In order to discuss additionally how differences in socioeconomic characteristics among Asian ethnic groups occur, Japanese were selected as an early immigrated Asian population, Korean as an intermediately immigrated one, and Vietnamese as a late immigrant. The data for this study are from the 5 percent public use sample of the 1980 Census of Population for the State of California.