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There are no detailed reports of clinical outcomes in Asian patients with nonalcoholic fatty liver disease (NAFLD) who undergo liver biopsy. We aimed to investigate the clinical outcomes of a large cohort of Asian patients with biopsy-proven NAFLD and evaluate the specific effects of nonalcoholic steatohepatitis and fibrosis stage. This multicenter registry-based retrospective cohort study, called the CLIONE (Clinical Outcome Nonalcoholic Fatty Liver Disease) in Asia, included 1398 patients. The median follow-up period was 4.6 years (range, 0.3–21.6 years), representing a total of 8874 person-years of follow-up. During that time, 47 patients died, and 1 patient underwent orthotopic liver transplantation. The leading cause of death was nonhepatic cancer (n = 10). The leading causes of liver-related death were liver failure (n = 9), hepatocellular carcinoma (HCC) (n = 8), and cholangiocellular carcinoma (n = 4). During follow-up, 37 patients developed HCC, 31 developed cardiovascular disease, and 68 developed nonhepatic cancer (mainly breast, stomach, and colon/rectum). Among our cohort of patients with NAFLD, liver-specific mortality was 2.34/1000 person-years (95% confidence interval [CI], 1.52–3.58), overall mortality was 5.34/1000 person-years (95% CI, 4.02–7.08), and HCC incidence was 4.17/1000 person-years (95% CI, 3.02–5.75). Liver fibrosis was independently associated with liver-related events but not overall mortality. Liver-related mortality was the leading cause of mortality in Asian patients with biopsy-confirmed NAFLD. Although fibrosis stage was independently associated with liver-related events, it was not associated with overall mortality after adjusting for confounders, such as histologic features of steatohepatitis. [Display omitted] [ABSTRACT FROM AUTHOR]

The diagnostic performance of the Fibrosis-4 (FIB-4) index and nonalcoholic fatty liver disease (NAFLD) fibrosis score (NFS) is poor in patients with type 2 diabetes mellitus (T2DM). We determined the usefulness of the Enhanced Liver Fibrosis (ELF) test in patients with T2DM. A total of 1228 patients with biopsy-proven NAFLD were enrolled. The diagnostic performance of the ELF test for predicting advanced fibrosis in participants with or without T2DM was evaluated in comparison with the FIB-4 index and NFS. Overall, the area under the curve of the ELF test for predicting advanced fibrosis was greater (0.828) than that of the FIB-4 index (0.727) and NFS (0.733). The diagnostic performance of the ELF test (area under the curve, 0.820) was also superior to that of the FIB-4 index (0.698) and NFS (0.700) in patients with T2DM. With the low cutoff values for each noninvasive test, the ELF test provided an acceptable false negative rate (cutoff value 9.8, 6.7%) in this population, unlike the FIB-4 index (1.30, 14.5%) and NFS (−1.455, 12.4%). After propensity score matching to avoid selection bias including age, sex, body mass index, and the prevalence of advanced fibrosis, the ELF test with a low cutoff value showed a high sensitivity (≥91.4%) and a high negative predictive value (≥96.8%), irrespective of the presence or absence of T2DM. The high diagnostic performance of the ELF test for predicting advanced fibrosis in individuals with or without T2DM could address an unmet medical need for accurate assessment of liver fibrosis in patients with diabetes and NAFLD. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Patients with Brugada syndrome (BrS) are known to have arrhythmic events after alcohol drinking and are recommended to avoid its excessive intake. Mechanisms underlying the alcohol‐induced cardiac events are however unknown. This study aimed to test the hypothesis whether activity of alcohol‐metabolizing enzymes determines fatal arrhythmic events after drinking alcohol. Methods: A total of 198 Japanese patients with BrS were enrolled in this study. These patients were classified into symptomatic (n = 90) and asymptomatic (n = 108) groups. The former was divided into an alcohol‐related group (syncope after alcohol drinking, n = 16) and an alcohol‐unrelated group (n = 74). Polymerase chain reaction was performed to determine genetic variants of genes encoding alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2). Results: The genotype distribution for ALDH2 was not significantly different between symptomatic and asymptomatic groups and between alcohol‐related and alcohol‐unrelated groups. The genotype distribution for ADH1B was not significantly different between symptomatic and asymptomatic groups, but the genotype ADH1B His/His was significantly more prevalent in the alcohol‐related group than in the alcohol‐unrelated group (81.3% vs 50%, P = .023). In multivariate logistic regression analysis, the genotype of ADH1B His/His was independently associated with syncope after alcohol drinking (odds ratio, 5.746; 95% confidence interval, 1.580‐28.421; P = .007). Conclusions: Arrhythmic events after alcohol drinking was associated with enhanced activity of alcohol‐metabolizing enzyme ADH1B in our cohort of BrS. Therefore, the lifestyle change to avoid the excessive alcohol intake deserves attention. [ABSTRACT FROM AUTHOR]

Background Anisotropic and slow conduction in the atrium underlie the development of atrial fibrillation (AF). This study aimed to investigate the P wave characteristics associated with the development of AF in patients with a biphasic P wave in the inferior leads. Methods Digital analysis of retrospectively recorded 12-lead electrocardiograms was performed to select patients with a biphasic P wave (positive/negative) in lead II from a database of 114,334 patients. Characteristics of the P wave in the inferior leads associated with incidence of AF were determined. Receiver operating characteristic curves dichotomized P wave variables were measured in each lead. Results A total of 141 patients (77 men; mean age, 64±19 years) were enrolled in this study. Twenty-nine (20.6%) patients developed AF (AF group) vs. 112 (79.6%) who did not (non-AF group) during a follow-up period of 50±62 months. The amplitude of the initial P wave portion in lead II was significantly larger in the AF group when compared with the non-AF group (77.3±77.0 µV vs. 51.0±30.1 µV, p =0.003), while the amplitude of the terminal P wave portion in lead III was significantly decreased in the AF group when compared with the non-AF group (−70.6±41.3 µV vs. −89.1±38.1 µV, p =0.024). The duration of the initial P wave portion in lead III was significantly longer in the AF group when compared with the non-AF group (52.7±34.6 ms vs. 35.8±30.4 ms, p =0.011). Multivariate Cox proportional-hazards analysis confirmed that the increased duration of the initial P wave portion in lead III (≥71 ms) was independently associated with AF development (hazard ratio 2.90, 95% confidence interval 1.16–7.11, p =0.02). Conclusion The analyses of the biphasic P wave in the inferior leads suggest that the development of AF could be attributed to increased atrial slow conduction. [ABSTRACT FROM AUTHOR]

Background J wave is known to be associated with increased risk of life-threatening ventricular arrhythmias in both structural and nonstructural heart disease. A documented history of ventricular tachycardia (VT) is also a known predictor for future arrhythmic events. The purpose of this study is to investigate prognostic factors in ventricular tachyarrhythmias in patients with an implanted defibrillator. Methods Intracardiac electrograms were thoroughly analyzed in patients with either an implanted implantable cardioverter-defibrillator or with cardiac resynchronization therapy with a defibrillator. The relation between the clinical characteristics and the device interventions for ventricular tachyarrhythmias was evaluated retrospectively with multivariate Cox proportional hazards models. Results This study enrolled a total of 160 patients who were followed for a mean period of 44 ± 28 months. Of these patients, 31 (19%) showed J wave and 77 (48%) showed documented VT before the device implantation. Multivariate Cox proportional hazards models revealed that the presence of J wave and the documented history of VT before the device implantation were independently associated with device intervention in patients with device implantation even after the adjustment of confounding factors (hazard ratio [HR], 2.90; 95% confidence interval [CI], 1.56–5.24; p = 0.001 and HR, 4.34; 95% CI, 2.43–8.05; p < 0.0001, respectively). Conclusion The presence of J wave and the documented history of VT prior to device implantation served as independent predictors of future device intervention for ventricular tachyarrhythmias. [ABSTRACT FROM AUTHOR]

Background Andersen-Tawil syndrome (ATS) is an autosomal dominant genetic or sporadic disorder characterized by ventricular arrhythmias (VAs), periodic paralyses, and dysmorphic features. The optimal pharmacological treatment of VAs in patients with ATS remains unknown. Objective We evaluated the efficacy and safety of flecainide for VAs in patients with ATS with KCNJ2 mutations. Methods Ten ATS probands (7 females; mean age 27 ± 11 years) were enrolled from 6 institutions. All of them had bidirectional VAs in spite of treatment with β-blockers (n = 6), but none of them had either aborted cardiac arrest or family history of sudden cardiac death. Twenty-four-hour Holter recording and treadmill exercise test (TMT) were performed before (baseline) and after oral flecainide therapy (150 ± 46 mg/d). Results Twenty-four-hour Holter recordings demonstrated that oral flecainide treatment significantly reduced the total number of VAs (from 38,407 ± 19,956 to 11,196 ± 14,773 per day; P = .003) and the number of the longest ventricular salvos (23 ± 19 to 5 ± 5; P = .01). At baseline, TMT induced nonsustained ventricular tachycardia (n = 7) or couplets of premature ventricular complex (n = 2); treatment with flecainide completely (n = 7) or partially (n = 2) suppressed these exercise-induced VAs ( P = .008). In contrast, the QRS duration, QT interval, and U-wave amplitude of the electrocardiogram were not altered by flecainide therapy. During a mean follow-up of 23 ± 11 months, no patients developed syncope or cardiac arrest after oral flecainide treatment. Conclusion This multicenter study suggests that oral flecainide therapy is an effective and safe means of suppressing VAs in patients with ATS with KCNJ2 mutations, though the U-wave amplitude remained unchanged by flecainide. [ABSTRACT FROM AUTHOR]

Objectives: An elongated styloid process may cause vascular Eagle syndrome that includes cervical carotid artery (CCA) dissection with stenosis and aneurysm formation. There are only four reported cases with vascular Eagle syndrome-related CCA dissecting aneurysm treated with carotid artery stenting (CAS). This is the first report of applying a dual-layer nitinol micromesh stent (CASPER) for vascular Eagle syndrome-related CCA dissecting aneurysm.Case Presentation: A 38-year-old man presented with a sudden onset of aphasia and right hemiplegia. Cerebral angiography demonstrated the left CCA dissecting aneurysm. The superior trunk of the left middle cerebral artery (MCA) was also occluded, and emergent thrombectomy was performed. Computed tomography with angiography (CTA) revealed that a 33 mm-long styloid process compressed the CCA at the aneurysm formation. Three weeks later, a CASPER stent was applied for the CCA aneurysm under the flow reversal system. Immediately after stent placement, blood flow in the aneurysm became stagnant, and postoperative CTA demonstrated regression of the aneurysm. The aneurysm did not recur for 6 months with no styloid process resection.Conclusions: The dual-layer nitinol micromesh stent (CASPER) was useful to treat vascular Eagle syndrome-related CCA dissecting aneurysm. [ABSTRACT FROM AUTHOR]

Background: J‐point elevation has been demonstrated to be associated with ventricular fibrillation (VF) and has been proposed as a cause of the J‐wave syndrome (JWS). A mutation of KCNJ8, S422L, was reported as a culprit gene. This study aimed to determine the prevalence of KCNJ8 mutations in a Japanese population with JWS or idiopathic VF (IVF). Methods: A total of 230 probands with JWS and IVF underwent genetic screening of KCNJ8. To analyze and compare clinical and electrocardiographic characteristics, the probands were divided into 4 groups: Brugada (Br) pattern only, early repolarization (ER) pattern only, Br and ER patterns, and true IVF. Results: The results of the genetic analysis revealed no S422L or other KCNJ8 mutations and indicated no significant difference between the groups. Conclusion: The KCNJ8 mutation showed no association with JWS or IVF among our Japanese patients. [ABSTRACT FROM AUTHOR]

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia syndrome characterized by episodic ventricular tachycardia induced by adrenergic stress. Although β‐blockers are used as first‐line therapy, their therapeutic effects are largely incomplete. Flecainide has recently been shown to modify the molecular defects in CPVT. The aim of this study was to investigate the effects of flecainide as an add‐on to conventional therapy on exercise‐induced ventricular arrhythmia and compare them with those of conventional therapy alone. Methods: The study included 5 CPVT patients with a mutation in RYR2. They experienced episodic arrhythmic events despite conventional β‐blocker therapy and were therefore given flecainide in addition. The effects of the addition of flecainide therapy on ventricular arrhythmia during exercise testing were compared with those of conventional therapy alone. Results: Both β‐blockers alone and with additional flecainide increased the maximal workload attained at the onset of ventricular arrhythmia; however, only flecainide increased the sinus rate at the onset of ventricular arrhythmias. Furthermore, flecainide increased the exercise capacity by preventing exercise‐induced arrhythmias. During a follow‐up period of 17±2 months, 1 patient experienced recurrent arrhythmic episodes that were associated with noncompliance. All patients reported improvements in their ability to perform the activities of daily living. Conclusion: Flecainide effectively reduced ventricular arrhythmias via a mechanism that differs from that of β‐blockers in genotype‐positive patients with CPVT. The specific effects of flecainide may be critical in the improvement noted in the patients' ability to perform daily activities. [ABSTRACT FROM AUTHOR]

Abstract: Green façades have long been used to reduce the overheating of buildings by excessive solar gain, but little research attention has been paid to the plant traits that reduce the surface temperature of urban structures. This study aimed to identify the key traits contributing to the cooling effects of green façades by comparing five vine plant species. The vines were trained to climb a plastic net that was attached on the freestanding walls under outdoor conditions. One of the walls was not covered with plants to serve as control. We measured the longest vine length, total number of leaves, percentage coverage, leaf transpiration rate, leaf solar transmittance, wall surface temperatures, global solar radiation on a vertical south surface (GSR) and ambient temperature. We identified the percentage coverage as the key trait determining the overall cooling effect: a statistically positive relationship (P < 0.001) was identified between the percentage coverage and the wall surface temperature reduction (WTR; the wall surface temperature differences between the non-covered wall and the covered wall) under GSR of more than 0.1 kW m−2. The percentage coverage was in turn found to be determined by the vine length. We also found that genotypic differences in WTRs that were not explained by those in the percentage coverage were related to those in leaf solar transmittance, indicating that this trait also contributed to the cooling effects. [Copyright &y& Elsevier]

Development of an effective low-cost anti-acquired immunodeficiency syndrome (AIDS) drugs is needed for treatment of AIDS patients in developing countries. Host cell lipid raft microdomains, which are enriched with cholesterol, glycolipids, ceramide, and gangliosides, are important for human immunodeficiency virus type 1 (HIV-1) entry. Retinoid analogs have been shown to modulate ceramide levels in the cell membrane, while cholera toxin B subunit (CT-B) specifically binds to the ganglioside GM1. In this study, we found that the acyclic retinoid analogs geranylgeranoic acid (GGA) and NIK-333 as well as CT-B efficiently attenuate CXCR4-tropic, but not CCR5-tropic, HIV-1 vector infection. We also found that GGA and NIK-333 suppress CXCR4-tropic HIV-1 infection by attenuating CXCR4 expression. CT-B also attenuated CXCR4-tropic HIV-1 infection, but did not suppress CXCR4 expression. These results suggest a distinct role for lipid raft microdomains in CXCR4- and CCR5-tropic HIV-1 infections and illuminate novel agents for the development of AIDS therapy. [ABSTRACT FROM AUTHOR]

Background: Short QT syndrome is one of the underlying disorders associated with ventricular fibrillation. However, the precise prognostic implication of a short QT interval remains unclear. Objective: The purpose of this study was to investigate the prevalence and long-term prognosis in patients with a shorter-than-normal QT interval in a large hospital-based population. Methods: We chose patients with a short Bazett QTc interval from a database consisting of 114,334 patients to determine the clinical characteristics and prognostic value of a short QT interval. Results: A total of 427 patients (mean age 43.4 ± 22.4 years) had a short QT interval with about a 1.2 times higher male predominance (234 men). The QTc interval was significantly longer in female than in male patients (363.8 ± 6.1 ms vs 357.1 ± 5.8 ms, P <.0001). The age-specific prevalence of patients with short QT interval was biphasic, peaking at young and old age. Atrial fibrillation and early repolarization were complicated with short QT interval in 39 (9.1%) and 26 (6.1%) patients, respectively. The prognosis of 327 patients (182 men; mean age, 46.4 ± 27.3 years) with a short QT interval could be assessed (mean follow-up period, 54.0 ± 62.0 months). During the follow-up, 2 patients, 1 of whom had early repolarization, developed life-threatening events, in contrast to 6 patients who died of noncardiac causes and did not have early repolarization. Conclusion: The prevalence of a short QT interval showed a slight male preponderance and biphasic age-dependent distribution in both genders. The complication rate of atrial fibrillation was higher in those with a short QT interval than in general populations. The long-term outcome suggested that early repolarization in a short QT interval might be associated with potential risk of lethal arrhythmia. [ABSTRACT FROM AUTHOR]

The renin-angiotensin system regulates the vascular fibrinolytic balance. In the human forearm vasculature, angiotensin-converting enzyme (ACE) inhibitors (ACE-Is) increase the release of t-PA through endogenous bradykinin. We tested the hypothesis that ACE inhibition and sex modulate the endogenous coronary release of tissue plasminogen activator (t-PA) in hypertensive patients. Seventy-three patients underwent diagnostic coronary angiography and had normal coronary angiograms. Thirty-three patients (21 men and 12 women) were treated with imidapril (5 mg/day) for 4 weeks (ACE-I group), and 40 (23 men and 17 women) were not treated with ACE-I (non-ACE-I group). All of the women were postmenopausal. Coronary blood flow in the left anterior descending artery was evaluated by measuring Doppler flow velocity. Net coronary t-PA release was determined as (coronary sinus-aorta gradient of t-PA)x(coronary blood flow)x[(100-hematocrit)/100]. Age, arterial pressure, heart rate, lipid levels, coronary flow, and the plasma level of t-PA at either aorta or coronary sinus were comparable among the 4 groups. In women, net t-PA release in the ACE-I group was significantly higher than that in the other groups (P<0.05; man non-ACE-I group: 1.4+/-2.6 ng/mL; woman non-ACE-I group: 1.4+/-3.1 ng/mL; man ACE-I group: -1.8+/-2.8 ng/mL; woman ACE-I group: 14.8+/-3.6 ng/mL). Correction for smoking status gave similar results. There was a significant negative correlation between serum ACE activity and coronary t-PA release in women (r=-0.38; P<0.05) but not in men. ACE inhibition increases coronary release of t-PA in women but not in men. [ABSTRACT FROM AUTHOR]

Background: Early repolarization, which was regarded as benign, has recently been associated with malignant arrhythmia. Despite the newly emerged importance of early repolarization, little is known about prevalence and QT interval of early repolarization. Methods: Early repolarization (defined as an elevation at the junction between QRS complex and ST segment ≥ 0.1 mV in at least 2 leads) was assessed in database containing 308,391 ECGs consisting of 102,065 patients (52,779 males and 49,286 females). Results: A total of 1,775 patients (mean age, 49 ± 30 years) with early repolarization were chosen (1.7% of total population). The prevalence of early repolarization was about 11-times higher in male patients (n = 1,623) than in female patients (n = 152). The prevalence of early repolarization was 1.4% at the age of 0-9 years, peaked (5.0%) at the age of 10-19 years, and progressively decreased with advancing age from 20 to 79 years (3.3, 2.1, 1.6, 0.9, 0.5, and 0.3% at the age of 20-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years, respectively). Bazett''s QTc interval of patients with early repolarization did not significantly differ among groups of each decade and between genders. Conclusion: The prevalence of early repolarization was both age- and gender-dependent in a hospital-based population. Yet, there was no association between QTc interval and age and between QTc interval and gender. [Copyright &y& Elsevier]

Background: Terminal P-wave inversion in lead V1 representing left atrial overload has been considered a precursor of atrial fibrillation (AF). Objective: The purpose of this study was to determine whether this P-wave morphologic characteristic can predict the development of AF. Methods: Digital analysis of 12-lead ECGs was performed to enroll patients with P terminal force ≥0.06 s × 2 mm in lead V1 from among a database of 308,391 ECG recordings. The prognostic value of ECG characteristics for developing AF was determined. Results: A total of 78 patients (mean age 52 ± 19 years) with left atrial overload were chosen from among 102,065 patients in the database. During mean follow-up of 43 months, 15 (19%) patients developed AF (AF group) versus 63 (81%) patients who did not (non-AF group). No significant difference was noted between the AF and non-AF groups with regard to the area, duration, and amplitude of the P-wave terminal portion in lead V1. In contrast, the area, duration, and amplitude of the P-wave initial portion in the same lead were significantly greater in the AF group than in the non-AF group (114.6 ± 73.0 μV × ms vs 73.1 ± 59.3 μV × ms, 42.2 ± 12.4 ms vs 35.7 ± 10.1 ms, and 94.0 ± 39.9 μV vs 68.8 ± 49.4 μV, respectively; P <.05 for each). Multivariate analysis confirmed that the area of the P-wave initial portion was independently associated with the development of AF (hazard ratio 4.02, 95% confidence interval 1.25–17.8; P = .018). Conclusion: P-wave initial portion in lead V1 was an independent risk stratifier of AF development in patients with marked left atrial overload. [Copyright &y& Elsevier]

Background: Terminal P-wave inversion in lead V(1) representing left atrial overload has been considered a precursor of atrial fibrillation (AF).Objective: The purpose of this study was to determine whether this P-wave morphologic characteristic can predict the development of AF.Methods: Digital analysis of 12-lead ECGs was performed to enroll patients with P terminal force > or =0.06 s x 2 mm in lead V(1) from among a database of 308,391 ECG recordings. The prognostic value of ECG characteristics for developing AF was determined.Results: A total of 78 patients (mean age 52 +/- 19 years) with left atrial overload were chosen from among 102,065 patients in the database. During mean follow-up of 43 months, 15 (19%) patients developed AF (AF group) versus 63 (81%) patients who did not (non-AF group). No significant difference was noted between the AF and non-AF groups with regard to the area, duration, and amplitude of the P-wave terminal portion in lead V(1). In contrast, the area, duration, and amplitude of the P-wave initial portion in the same lead were significantly greater in the AF group than in the non-AF group (114.6 +/- 73.0 microV x ms vs 73.1 +/- 59.3 microV x ms, 42.2 +/- 12.4 ms vs 35.7 +/- 10.1 ms, and 94.0 +/- 39.9 microV vs 68.8 +/- 49.4 microV, respectively; P <.05 for each). Multivariate analysis confirmed that the area of the P-wave initial portion was independently associated with the development of AF (hazard ratio 4.02, 95% confidence interval 1.25-17.8; P = .018).Conclusion: P-wave initial portion in lead V(1) was an independent risk stratifier of AF development in patients with marked left atrial overload. [ABSTRACT FROM AUTHOR]

Polyethers possessing 9,9-diarylfluorene moieties in the main chain (F-PEs 3) were synthesized in 85-99% yields by the polycondensation of 9,9-bis(hydroxyaryl)fluorenes with alkyl ditosylates in the presence of cesium carbonate. Molecular weight of the F-PEs was dependent on the structure of the ditosylate 1; cyclohexyl-1,4-dimethylene (1a), 1,2-ethylene (1b), 1,3-trimethylene (1c), and 1,6-hexamethylene (1d). Higher molecular weight F-PEs (Mn 32000-60000, Mw 74000-160000) was obtained when longer alkyl chain ditosylates (1a and 1d) were used. The F-PEs showed good solubility toward various organic solvents such as toluene and high 5% weight loss temperature (Td5: 424-447 °C). The glass transition temperature of F-PEs (Tg) was ranging from 147 to 220°C. No melting point (Tm) was observed. F-PEs showed high water-resistance. The transmittance of F-PEs in film state (thickness: 21-32 µm) reached over 90% in the visible region. The F-PEs exhibited high refractive indices in a range of 1.62-1.66 at 590 nm in addition to sufficiently low birefringence values, probably due to the cardo structure of the fluorene moiety placed in the main chain. The structural dependence of dispersing ability to fullerene C60 was investigated. [ABSTRACT FROM AUTHOR]

Polysiloxanes possessing 9,9-diarylfluorene moieties (F-PSiOs 3) were synthesized in 83-91% yield by the polycondensation of 9,9-bis(hydroxyaryl or hydroxyethoxyphenyl)fluorenes with Ph2SiCI2 in the presence of pyridine. F-PSiOs with higher molecular weight (Mn 19000-32000, Mw 32000-75000) were obtained, when less polar solvents such as toluene and CCI4 were used as the polymerization solvent. The F-PSiOs showed good solubility toward various organic solvents, high 5% weight loss temperature (Td5: 443-544°C), and lower glass transition temperature (Tg: 100-171 °C) under nitrogen atmosphere rather than 9,9-diaryifluorene—based polymers reported. On the other hand, no melting point (Tm) was observed owing to the amorphous nature of F-PSiOs. Dynamic viscoelasticity of F-PSiO film was also measured to evaluate the thermal behavior. The transmittance of F-PSiOs in the film state (thickness: 62-70μm) reached over 90% in the visible region. The F-PSiOs exhibited remarkably high refractive index values in a range of 1.64-1.66 at 589 nm in addition to sufficiently low birefringence values, probably due to the cardo structure of the fluorene moiety placed in the main chain. [ABSTRACT FROM AUTHOR]

Control of light diffusion or direction of transmitted light were generated from polymer composites, consisting of single fiber and surrounded polymer matrix, using a fiber whose cross-section is triangle shape. Light diffusion property was drastically changed by following two ways, slight rotation of samples with respect to the direction of incident light, or little adjustment of refractive index of polymer matrix. If triangle fiber was used, spatial pattern of light diffusion was strongly dependent on incident light direction or refractive index ratio between fiber and polymer matrix, whereas, if circular fiber was used, they were relatively insensitive to incident light direction or refractive index ratio. In this research we also succeeded in polarization separation, by use of a monofilament birefringent fiber. The fabrication procedure was same except that fiber was birefringent. Since the light diffusion property was drastically influenced by the shift of refractive index, spatial patterns of light diffusion were quite different between two polarized light (axis of electric field are vertical each other) in birefringent fiber, thus polarized light was separated to different directions. In our samples, we could separate more than 95% of polarized light into two different directions. [ABSTRACT FROM AUTHOR]