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Study Design. Prospective observational study. Objective. To assess the influence of pain sensitivity on surgical outcomes after lumbar spine surgery in patients with lumbar spinal stenosis (LSS). Summary of Background Data. No previous study has investigated the relationship between the surgical outcomes for LSS and pain sensitivity questionnaire (PSQ) scores. Methods. The study included 171 patients who were scheduled to undergo spine surgery for LSS. On the basis of their PSQ scores, patients were assigned to either a low (PSQ score < 6.5, n = 87) or high PSQ group (PSQ score ≥ 6.5, n = 84). The primary outcome was the Oswestry Disability Index (ODI) at 12 months after surgery. Results. The ODI at 12 months after surgery was significantly lower in the low PSQ group than in the high PSQ group. Twelve months after surgery, the mean ODI scores (95% confidence interval) in the low and high PSQ groups were 21.1 (16.8-25.5) and 29.6 (25.0- 34.1), respectively. The difference (95% confidence interval) in the ODI between the 2 groups was 3.2 (-14.7 to -2.2) (P = 0.009). There were significant differences in the secondary endpoints, including the ODI and visual analogue scale (VAS) scores for back and leg pain, in the follow-up assessments during a 12-month period after surgery, between the 2 groups (PSQ group; P < 0.001 for the ODI, VAS score for back pain, and VAS score for leg pain). However, the patterns of changes of the ODI and VAS scores for back pain and leg pain in the follow-up assessments during a 12-month period were not significantly different (interaction between the PSQ group and follow-up assessment time; P = 0.757, 0.126, and 0.950, respectively). Conclusion. Patients with high pain sensitivity may display less improvement in back pain, leg pain, and disability after surgery for LSS compared with patients with low pain sensitivity. Furthermore, the PSQ can be used to predict surgical outcomes after spine surgery for LSS. [ABSTRACT FROM AUTHOR]

Many previous sodium cooled fast reactors (SFRs) adopted steam Rankine cycle as the power conversion system. However, the concern of sodium water reaction has been one of the major design issues of a SFR system. As an alternative to the steam Rankine cycle, several closed Brayton cycles including supercritical CO2 cycle, helium cycle and nitrogen cycle have been suggested recently. In this paper, these alternative gas Brayton cycles will be compared to each other in terms of cycle performance and physical size for small modular SFR application. Several new layouts are suggested for each fluid while considering the turbomachinery design and the total system volume. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate actual conditions associated with veterinary anesthetic drug use in Korea, and to obtain responses from Korean veterinarians and researchers pertaining to the use of anesthetic drugs. To accomplish this, a nationwide survey was issued to veterinarians working at animal hospitals and to researchers in the Korean Association for Laboratory Animal Science (KALAS). A self-administered questionnaire-based survey was then conducted in which respondents were asked questions about actual conditions associated with the use of animal anesthetic drugs. The survey revealed that the distribution and management of animal medicines in Korea was quite vulnerable to misuse or abuse due to a variety of factors. Therefore, a relevant regulatory system should be strictly enforced to protect vulnerable individuals from abuse or misuse. [ABSTRACT FROM AUTHOR]

A blue light emitting diode based on wide band gap host for a blue fluorescence light emitting layer has been developed to fabricate hybrid white organic light emitting diode comprising of a fluorescence blue and a phosphorescence red light emitting layers. We have tested various wide band gap host materials including CBP, BAlq, and TcTa, and among them the device with TcTa host has shown good performance which could be attributed to tight exciton confinement. A phosphorescence red dopant (RD) has been introduced into BAlq layer to harvest triplet states of the fluorescence blue emission layer and we have succeeded in obtaining the balanced emission of the blue and the red emissions with high efficiency. The device showed the maximum external quantum efficiency of 16% at 0.1 mA/cm2 and 13% of external quantum efficiency with (0.29, 0.23) of CIE coordinates at 10 mA/cm2. [ABSTRACT FROM AUTHOR]

A novel series of poly(10‐hexyl‐phenothiazine‐S,S‐dioxide‐3,7‐diyl) and poly(9,9′‐dioctyl‐fluorene‐2,7‐diyl‐alt‐10‐hexyl‐3,7‐phenothiazine‐S,S‐dioxide) (PFPTZ‐SS) compounds were synthesized through Ni(0)‐mediated Yamamoto polymerization and Pd(II)‐catalyzed Suzuki polymerization. The synthesized polymers were characterized by 1H NMR spectroscopy and elemental analysis and showed higher glass transition temperatures than that of pristine polyfluorene. In terms of photoluminescence (PL), the PFPTZ‐SS compounds were highly fluorescent with bright blue emissions in the solid state. Light‐emitting devices were fabricated with these polymers in an indium tin oxide/poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate)/polymer/Ca/Al configuration. The electroluminescence (EL) of the copolymers differed from the PL characteristics: the EL device exhibited a redshifted greenish‐blue emission in contrast to the blue emission observed in the PL. Additionally, this unique phenothiazine‐S,S‐dioxide property, triggered by the introduction of an electron‐deficient SO2 unit into the electron‐rich phenothiazine, gave rise to improvements in the brightness, maximum luminescence intensity, and quantum efficiency of the EL devices fabricated with PFPTZ‐SS. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1236–1246, 2007 [ABSTRACT FROM AUTHOR]

White organic light emitting devices (OLEDs) with an RGB stacked multilayer structure are demonstrated. In RGB staked OLEDs, blue emitting 1,4-bis[2,2-diphenylvinyl]biphenyl (DPVBi), green emitting quinacridone (QD), and red emitting [2,6-bis[2-[5-(dibutylamino)phenyl]vinyl]-4H-pyran-4-ylidene]propanedinitrile (DADB) were used. Through the optimization of the device structure, the pure white light emission with CIE coordinates of (0.33,0.33) at 20 mA/cm 2 was obtained, at which the color temperature and color rendering index were 5560 K and 79, respectively. Its maximum luminance was 14,000 cd/m 2 at 12.6 V, and the luminance efficiency was 1.34 lm/W at 100 cd/m 2 . [ABSTRACT FROM AUTHOR]

We have investigated a relationship between device performances and host properties in the emissive layer (EML) of iridium(III) bis(4′,6′-difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate doped blue phosphorescent organic light-emitting diodes (PHOLEDs). We found that the recombination zone as well as charge carrier injection properties of the EML could be systematically engineered through a mixed host system. Therefore, light-emitting performances of blue PHOLEDs were greatly improved with external quantum and power efficiencies of 20.5% and 43.5 lm/W at a luminance of 56 cd/m2, respectively. [ABSTRACT FROM AUTHOR]

Cesium iodide (CsI) coated graphite is a good candidate for an electrode material of a thermionic power generation device due to its low work function. In this letter, a thermionic device with a nanometer-scale vacuum gap between a CsI coated graphite emitter and a collector will be investigated while considering various gap-size effects. It is shown that a nanometer scale gap-size not only affects electron transport but also photon transport, and that all of these effects must be taken into account when estimating the device’s performance. [ABSTRACT FROM AUTHOR]

We report a significant enhancement and a reduced efficiency roll-off in blue and white phosphorescent organic light-emitting diodes (PHOLEDs) based on a mixed host structure. The combination of a hole-transport-type host and an electron-transport-type host as a mixed host emissive layer resulted in an effective charge carrier injection and distribution of the recombination zone, and therefore highly efficient blue PHOLEDs with peak external quantum and power efficiencies of 21.6% and 44.9 lm/W were achieved. Moreover, white PHOLEDs with a mixed host structure showed a power efficiency of 37 lm/W, which is over four times higher than 8.7 lm/W in a single host structure device at a luminance of 1000 cd/m2. [ABSTRACT FROM AUTHOR]

A supercritical CO2 (S-CO2) Brayton cycle is expected to have high compactness, simple configuration, and competitive efficiency. These advantages originated from CO2 nonideal gas properties near the critical point. However, the strong real gas effect makes the design challenging. Among components, turbomachinery is most affected by the real gas effects of S-CO2. In order to obtain accurate design of the turbomachinery, accurate loss models are needed. Windage loss is one of the external losses that determines the motor load and is responsible for heat generation due to friction. The overall turbomachinery efficiency is greatly affected by the windage loss especially in an S-CO2 power cycle due to high fluid density and high rotational speed. Therefore, an accurate windage loss model that can reflect the real gas effect of CO2 near the critical point is essential to obtain accurate design of the turbomachinery as well as the power cycle. In this paper, existing windage loss models are compared under S-CO2 conditions first, and the applicability of each model is evaluated. The comparison is to understand how much turbomachinery performance uncertainty can be expected due to the windage loss models and to suggest the way to improve the models. [ABSTRACT FROM AUTHOR]

This study was conducted to compare the hemostatic efficacy of three ferric subsulfate- and chitosan-based styptics as a powder and a gel containing ferric subsulfate and chitosan (FSC-PO and FSC-G, respectively) and a soaked pad containing ferric subsulfate and lidocaine (FSL-SP) using a rat tail bleeding model. The cytotoxicity of the styptics against L-929 mouse fibroblasts was also evaluated using a cell counting kit-8 assay. Four groups of 10 rats each were assigned to the three different styptics and a non-treated control groups. Rat tail tips were transected, after which styptics were applied with pressure. The wounds were observed for hemostasis for 3 min, then irrigated with saline to check for recurrent hemorrhage. L-929 mouse fibroblasts were exposed to extracts of the styptics (100 mg/ mL) and their dilutions (1:10, 1:100, and 1:1,000). FSC-PO and FSC-G more effectively controlled initial hemorrhage than FSL-SP (p = 0.033). Additionally, FSC-PO and FSC-G more effectively maintained hemostasis than the control group (p = 0.02 and p < 0.01, respectively). However, all styptics showed enhanced cytotoxicity against L-929 cells in a dose-dependent manner. Therefore, although FSC-PO and FSC-G would be recommended to control hemorrhage, the benefits of styptics must be balanced against the clinical significance of their cytotoxicity. [ABSTRACT FROM AUTHOR]

In this paper, recent advances in Ocean Nuclear Power Plants (ONPPs) are reviewed, including their general arrangement, design parameters, and safety features. The development of ONPP concepts have continued due to initiatives taking place in France, Russia, South Korea, and the United States. Russia's first floating nuclear power stations utilizing the PWR technology (KLT-40S) and the spar-type offshore floating nuclear power plant designed by a research group in United States are considered herein. The APR1400 and SMART mounted Gravity Based Structure (GBS)-type ONPPs proposed by a research group in South Korea are also considered. In addition, a submerged-type ONPP designed by DCNS of France is taken into account. Last, issues and challenges related to ONPPs are discussed and summarized. [ABSTRACT FROM AUTHOR]

To modify SiO 2 dielectric surface of bottom-contact OTFT device, octadecyltriethoxysilane (OTES) was used to find optimum condition of surface modification for triethoxysilane derivatives. Either spin-coating method or solution dipping method was applied to modify the dielectric surface with OTES. Optimization process was performed with varying solution concentration, reaction time and so on. Through surface modification of OTFT, 0.01-0.04 cm 2 /V/s of hole mobilities were observed depending on modification conditions. [ABSTRACT FROM AUTHOR]

White light-emitting devices were fabricated using the blends of blue, green, red emissive polymers of poly[9,9-(2′-ethylhexyl)fluorene] (PEHF), poly(9,9-dioctylfluorene-2,7-vinylene) (POFV), poly(2-(3′,7′-dimethyloctyloxy)-5-methoxy-1,4-phenylene-1-cyanovinylene) (CN-PPV) and poly(2-(2′-ethylhexyloxy)-5-methoxy-1,4-phenylenevinylene) (MEH-PPV). Inefficient energy transfers between the blue polymer and the green or the red polymer, which was observed in PL spectra of the blend films, provides a good advantage to get a white light emission due to better blend ratio controllability. The EL devices were fabricated with ITO/PEDOT/blend/Ca/Al configuration and good white light-emission was obtained for a certain blend ratio. The light-emission was observable from 4 V and the maximum brightness of 400 cd/m 2 was obtained with the device. [ABSTRACT FROM AUTHOR]

Due to small footprint and high efficiency, a Supercritical CO2 (S-CO2) power cycle is considered to be one of the promising next-generation power cycles. Although S-CO2 is reported as a powerful cleaning agent, the performance of a power system operating with S-CO2 will also inevitably degrade over time. Previous researchers have shown that turbomachinery deterioration could be a major subject regarding the system performance degradation. Nevertheless, no quantitative evaluation has yet been made so far. In this study, the impact of the performance degradation of the S-CO2 turbomachinery on the overall performance of the system is analyzed quantitatively. The concept of Health Parameter is used to simulate turbomachinery degradation. To quantify the impact, an S-CO2 direct-cycle small modular reactor is selected as a target system. A transient analysis platform is built using a nuclear system safety analysis code and the deep neural network (DNN)-based S-CO2 turbomachinery off-design performance model. System dynamics are evaluated for primary frequency control ability and secondary load-following capability. Results show that the control problems during the transient state can occur when the output fluctuations are large and the performance degradation is severe. It has been confirmed that even control failures of the PID controllers can occur. Therefore, the performance degradation of turbomachinery must be monitored and considered, for an operation strategy for S-CO2 systems. [ABSTRACT FROM AUTHOR]

Background Codman's paradox reveals a misunderstanding of geometry in orthopedic practice. Physicians often encounter situations that cannot be understood intuitively during orthopedic interventions such as corrective osteotomy. Occasionally, unexpected angular or rotational deformity occurs during surgery. This study aimed to draw the attention of orthopedic surgeons toward the concepts of orientation and rotation and demonstrate the potential for unexpected deformity after orthopedic interventions. This study focused on three situations: shoulder arthrodesis, femoral varization derotational osteotomy, and femoral derotation osteotomy. Methods First, a shoulder model was generated to calculate unexpected rotational deformity to demonstrate Codman's paradox. Second, femoral varization derotational osteotomy was simulated using a cylinder model. Third, a reconstructed femoral model was used to calculate unexpected angular or rotational deformity during femoral derotation osteotomy. Results Unexpected external rotation was found after forward elevation and abduction of the shoulder joint. In the varization and derotation model, closed-wedge osteotomy and additional derotation resulted in an unexpected extension and valgus deformity, namely, undercorrection of coxa valga. After femoral derotational osteotomy, varization and extension of the distal fragment occurred, although the extension was negligible. Conclusions Surgeons should be aware of unexpected angular deformity after surgical procedure involving bony areas. The degree of deformity differs depending on the context of the surgical procedure. However, this study reveals that notable deformities can be expected during orthopedic procedures such as femoral varization derotational osteotomy. [ABSTRACT FROM AUTHOR]

Drug repositioning is one of the most rapidly emerging fields of study. This concept is anchored on the principle that diseases have similar damaged or affected signaling pathways. Recently, drugs have been repositioned not only for their alternative therapeutic uses but also for their applications as biomaterials in various fields. However, medical drugs as biomaterials are rarely focused on in reviews. Fragmin and protamine have been recently the sources of increasing attention in the field of tissue engineering and regenerative medicine. Fragmin and protamine have been manufactured primarily as a safe antidote for the circulating heparin. Lately, these drugs have been utilized as either micro- or nanoparticle biomaterials. In this paper, we will briefly describe the concept of drug repositioning and some of the medical drugs that have been repurposed for their alternative therapeutic uses. Also, this will feature the historical background of the studies focused on fragmin/protamine micro/nanoparticles (F/P M/NPs) and their applications as biomaterials in tissue engineering, stem cell therapy, and regenerative medicine. [ABSTRACT FROM AUTHOR]

Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering. [ABSTRACT FROM AUTHOR]

Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering. [ABSTRACT FROM AUTHOR]

New alternating polymers based on 2,7-dibromo-9,9-bis(4-octyloxy-phenyl) fluorene (BOPF), poly{9,9-bis-(4-octyloxy-phenyl)-fluorene-2,7-diyl- co-3,7-bis(1-cyanovinyl-3-phenothienyl)-1-(2′-ethylhexyloxy)-4-methoxybenzene-3′,7′-diyl} (PFPCVBs), have been designed, synthesized, and characterized. The PFPCVBs were synthesized through palladium-catalyzed Suzuki coupling reactions. BOPF and 3′,7-bis[3-(7′-bromo-phenothienyl)-1-cyanovinyl]-1-(2′-ethyl-hexyloxy)-4-methoxy-benzene (BPCVB) were used as the blue- and orange-light-emitting chromophores, respectively. These polymers were found to be thermally stable and readily soluble in common organic solvents. The photoluminescence (PL) spectra of the synthesized polymers contain both blue and orange emissions from these two chromophores. Moreover, by adjusting the BOPF and BPCVB contents, white-light emission can be obtained from a single PFPCVB polymer. EL devices with ITO/PEDOT:PSS/polymer/Balq/LiF/Al configurations using these polymers were found to produce blue and orange emissions. The EL emissions of PFPCVB 025 and PCPCVB 050 were found to result in white electroluminescence with Commission Internationale de L’Eclairage (CIE) coordinates of (0.30, 0.36) and (0.33, 0.39), respectively. The EL emissions of PFPCVB 025 are stable with respect to variation in the voltage, and were found to have the coordinates (0.30, 0.36), (0.29, 0.35), and (0.28, 0.34) at various device driving voltages. The device using PFPCVB 050 exhibits a maximum brightness of 1740 cd/m 2, a maximum current efficiency of 1.95 cd/A, and a maximum external quantum efficiency of 0.9%. [ABSTRACT FROM AUTHOR]

A series of fluorene‐based copolymers composed of blue‐ and orange‐light‐emitting comonomers were synthesized through palladium‐catalyzed Suzuki coupling reactions. 9,9‐Dihexylfluorene and 2‐(2,6‐bis‐{2‐[1‐(9,9‐dihexyl‐9H‐fluoren‐2‐yl)‐1,2,3,4‐tetrahydroquinolin‐6‐yl]‐vinyl}‐pyran‐4‐ylidene)‐malononitrile (DCMF) were used as the blue‐ and orange‐light‐emitting chromophores, respectively. The resulting single polymers exhibited simultaneous blue (423/450 nm) and orange (580–600 nm) emissions from these two chromophores. By adjusting the fluorene and DCMF contents, white light emission could be obtained from a single polymer; a device with an ITO/PEDOT:PSS/polymer/Ca/Al configuration was found to exhibit pure white electroluminescence with Commission Internationale de L'Eclairage (CIE) coordinates of (0.33, 0.31), a maximum brightness of 1180 cd/m2, and a current efficiency of 0.60 cd/A. Furthermore, the white light emission of this device was found to be very stable with respect to variation of the driving voltage. The CIE coordinates of the device were (0.32, 0.29), (0.32, 0.29), and (0.33, 0.31) for driving voltages of 7, 8, and 10 V, respectively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3380–3390, 2007 [ABSTRACT FROM AUTHOR]

Novel conjugated polyfluorene copolymers, poly[9,9‐dihexylfluorene‐2,7‐diyl‐co‐(2,5‐bis(4′‐diphenylaminostyryl)‐phenylene‐1,4‐diyl)]s (PGs), have been synthesized by nickel(0)‐mediated polymerization from 2,7‐dibromo‐9,9‐dihexylfluorene and 1,4′‐dibromo‐2,5‐bis(4‐diphenylaminostyryl)benzene with various molar ratios of the monomers. Because of the incorporation of triphenylamine (TPA) moieties, PGs exhibit much higher HOMO levels than the corresponding polyfluorene homopolymers and are able to facilitate hole injection into the polymer layer from the anode electrode in light‐emitting diodes. Conventional polymeric light‐emitting devices with the configuration ITO/PEDOT:PSS/polymer/Ca/Al have been fabricated. A light‐emitting device produced with one of the PG copolymers (PG10) as the emitting layer exhibited a voltage‐independent and stable bluish‐green emission with color coordinates of (0.22, 0.42) at 5 V. The maximum brightness and current efficiency of the PG10 device were 3370 cd/m2 (at 9.6 V) and 0.6 cd/A, respectively. To realize a white polymeric light‐emitting diode, PG10 as the host material was blended with 1.0 wt % of a red‐light‐emitting polymer, poly[9,9‐dioctylfluorene‐2,7‐diyl‐alt‐2,5‐bis(2‐thienyl‐2‐cyanovinyl)‐1‐(2′‐ethylhexyloxy)‐4‐methoxybenzene‐5′,5′‐diyl] (PFR4‐S), and poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylenevinylene] (MEH‐PPV). The device based on PG10:PFR4‐S showed an almost perfect pure white electroluminescence emission, with Commission Internationale de l''Eclairage (CIE) coordinates of (0.33, 0.36) at 8 V; for the PG10:MEH‐PPV device, the CIE coordinates at this voltage were (0.30, 0.40) with a maximum brightness of 1930 cd/m2. Moreover, the white‐light emission from the PG10:PFR4‐S device was stable even at different driving voltages and had CIE coordinates of (0.34, 0.36) at 6 V and (0.31, 0.35) at 10 V. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1199–1209, 2007 [ABSTRACT FROM AUTHOR]

We have applied spectroscopic ellipsometry to obtain the optical constants, i.e., refractive indices (n) and extinction coefficients (k) of a thin tris (8-hydroxyquinoline) aluminum (Alq3) film evaporated on the top of 300-nm-thick SiO2 layer on a silicon substrate. Using a spectroscopic ellipsometer we collected the ellipsometric data of Ψ and Δ at 3 incident angles of 65°, 70° and 75° and 226 energies of 1.5 eV to 6.0 eV. For the organic sample, we adopted a simple two-film model consisting of ambient/organic film/SiO2 film/silicon substrate. Using the multiple oscillators of Tauc-Lorentz (TL) dispersion function and the two-film model, we obtained the thickness of the Alq3 film. By data inversion technique, the spectra of n and k for the Alq3 film are calculated from measured Ψ and Δ at each photon energy when the film thickness is fixed to a value obtained by the TL dispersion fitting. The extrapolation of optical function near band gap yields the band gap of 2.64 eV for Alq3 film. [ABSTRACT FROM AUTHOR]

We fabricate organic light-emitting devices with polyacrylate passivation layers formed by using spin coating method and compare the rate of degradation to an organic light-emitting device without the passivation layer. The fabrication process of passivation layer did not influence the electrical and the emissive properties of the device. Polyacrylate passivation layers enhanced the longevity of the device than that of the non-encapsulated device, and its behavior was dependent on the polyacrylate film thickness. [ABSTRACT FROM AUTHOR]

Soluble conjugated polymers such as poly(3-hexylthiophene) (P3HT) are very promising candidates for a cheap electronic device on various substrates. In this study we report the effects of O[sub 2] plasma treatment of the substrates on the electrical properties of P3HT organic thin-film transistors and metal/insulator/organic semiconductor capacitors. Based on the results of a capacitance–voltage measurement, the effective charge density in the interface between P3HT and SiO[sub 2] layer treated by O[sub 2] plasma for 30 s was approximately -18.3 nC/cm[sup 2]. When the period of O[sub 2] plasma treatment was longer than 30 s, the field-effect mobility decreased since the amount of charge and the relaxation time constant of interface traps increased. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

An optical functional film applicable to various lighting devices is demonstrated in this study. The phase separation of two immiscible polymers in a common solvent was used to fabricate the film. In this paper, a self-organized lens-like structure is realized in this manner with optical OLED functional film. For an OLED, there are a few optical drawbacks, including light confinement or viewing angle distortion. By applying the optical film to an OLED, the angular spectra distortion resulting from the designed organic stack which produced the highest efficiency was successfully stabilized, simultaneously enhancing the efficiency of the OLED. We prove the effect of the film on the efficiency of OLEDs through an optical simulation. With the capability to overcome the main drawbacks of OLEDs, we contend that the proposed film can be applied to various lighting devices. [ABSTRACT FROM AUTHOR]