KCNN2 polymorphisms and cardiac tachyarrhythmias

Potassium calcium-activated channel subfamily N member 2 (KCNN2) encodes an integral membrane protein that forms small-conductance calcium-activated potassium (SK) channels. Recent studies in animal models show that SK channels are important in atrial and ventricular repolarization and arrhythmogenesis. However, the importance of SK channels in human arrhythmia remains unclear. The purpose of the present study was to test the association between genetic polymorphism of the SK2 channel and the occurrence of cardiac tachyarrhythmias in humans. We enrolled 327 Han Chinese, including 72 with clinically significant ventricular tachyarrhythmias (VTa) who had a history of aborted sudden cardiac death (SCD) or unexplained syncope, 98 with a history of atrial fibrillation (AF), and 144 normal controls. We genotyped 12 representative tag single nucleotide polymorphisms (SNPs) across a 141-kb genetic region containing the KCNN2 gene; these captured the full haplotype information. The rs13184658 and rs10076582 variants of KCNN2 were associated with VTa in both the additive and dominant models (odds ratio [OR] 2.89, 95% confidence interval [CI] = 1.505-5.545, P = 0.001; and OR 2.55, 95% CI = 1.428-4.566, P = 0.002, respectively). After adjustment for potential risk factors, the association remained significant. The population attributable risks of these 2 variants of VTa were 17.3% and 10.6%, respectively. One variant (rs13184658) showed weak but significant association with AF in a dominant model (OR 1.91, CI = 1.025-3.570], P = 0.042). There was a significant association between the KCNN2 variants and clinically significant VTa. These findings suggest an association between KCNN2 and VTa; it also appears that KCNN2 variants may be adjunctive markers for risk stratification in patients susceptible to SCD

High Photoelectric Conversion Efficiency of Metal Phthalocyanine/Fullerene Heterojunction Photovoltaic Device

This paper introduces the fundamental physical characteristics of organic photovoltaic (OPV) devices. Photoelectric conversion efficiency is crucial to the evaluation of quality in OPV devices, and enhancing efficiency has been spurring on researchers to seek alternatives to this problem. In this paper, we focus on organic photovoltaic (OPV) devices and review several approaches to enhance the energy conversion efficiency of small molecular heterojunction OPV devices based on an optimal metal-phthalocyanine/fullerene (C60) planar heterojunction thin film structure. For the sake of discussion, these mechanisms have been divided into electrical and optical sections: (1) Electrical: Modification on electrodes or active regions to benefit carrier injection, charge transport and exciton dissociation; (2) Optical: Optional architectures or infilling to promote photon confinement and enhance absorption

Carrier Injection and Transport in Blue Phosphorescent Organic Light-Emitting Device with Oxadiazole Host

In this paper, we investigate the carrier injection and transport characteristics in iridium(III)bis[4,6-(di-fluorophenyl)-pyridinato-N,C2']picolinate (FIrpic) doped phosphorescent organic light-emitting devices (OLEDs) with oxadiazole (OXD) as the bipolar host material of the emitting layer (EML). When doping Firpic inside the OXD, the driving voltage of OLEDs greatly decreases because FIrpic dopants facilitate electron injection and electron transport from the electron-transporting layer (ETL) into the EML. With increasing dopant concentration, the recombination zone shifts toward the anode side, analyzed with electroluminescence (EL) spectra. Besides, EL redshifts were also observed with increasing driving voltage, which means the electron mobility is more sensitive to the electric field than the hole mobility. To further investigate carrier injection and transport characteristics, FIrpic was intentionally undoped at different positions inside the EML. When FIrpic was undoped close to the ETL, driving voltage increased significantly which proves the dopant-assisted-electron-injection characteristic in this OLED. When the undoped layer is near the electron blocking layer, the driving voltage is only slightly increased, but the current efficiency is greatly reduced because the main recombination zone was undoped. However, non-negligible FIrpic emission is still observed which means the recombination zone penetrates inside the EML due to certain hole-transporting characteristics of the OXD

The Study of High Contrast Display Devices

本論文中將介紹兩種高對比度顯示元件。其一為內含黑色陰電極的有機發光元件(OLED)，另一種為利用反射式液晶顯示元件(RLCD)與透明OLED元件垂直整合並封裝成一個單一混成元件。新的黑色陰極的OLED內含有破壞性干涉的共振腔結構，共振腔中所填充的介電層為一具有高吸收特性與高導電特性。介電層的材料是利用銀粒子摻雜有機材料MPPDI而來。有機材料吸收的增強與導電性的增加主要分別來自奈米銀離子的摻雜所造成的表面電漿共振所引發的吸收增強與銀本身電性較佳的結果。未做表面抗反射處理的黑色陰電極的OLED所導致的反射超低大約只有4%，這個值很接近空氣與玻璃介面的反射；在人眼最敏感的波長550 nm部份，也只有5.5%。此元件在廣視角的影像表現很好，反射率也很低，在斜視角60o時有反射率12.3％在550 nm，因此有利於當成手持顯示裝置在戶外使用。再者，此元件的電性與壽命表現也與一般傳統元件相當。造中結合兩種不同元件RLCD與透明OLED具有相當困難度，我們發展了一套適當的製造流程設計以使得OLED的光電特性不受製程影響。在元件的儲存狀態下壽命測試中，可發現透明OLED在此混成元件中可以保有比傳統封裝方式的元件還久的特性，原因來自於液晶也形成另一型式的保護層保護著OLED。In this thesis, two kinds of high contrast display devices were demonstrated. One is an organic light-emitting device (OLED) with absorptive and destructive interference black cathode (ADIBC) structure. The other is a hybrid device vertically integrated with a reflective liquid crystal display (RLCD) and a transparent OLED in one unit cell.he novel ADIBC-OLED constructed with a destructive interference cavity filled with a highly absorptive and conductively thin-film which was fabricated by doping Ag into N,N''-Bis (2,6-diisopropylphenyl)-1,7-bis (4-methoxy-phenyl) perylene-3,4,9,10 -tetracarboxydiimide (MPPDI). Strong absorption and high conduction of thin-film resulted from plasmon-enhanced absorption and electrical properties improvement of Ag nanoparticles. Reflection from the ADIBC-OLED is as low as 4% at 800 nm, and 5.5% at 550 nm. Besides, low reflection was also achieved at oblique viewing angles (12.3% at 550 nm with 60o) with good image quality under outdoor environments. Such a ADIBC-OLED exhibited a nearly identical J-V and lifetime performances to the control device.abrication and integration issues of the transflective (TR-) hybrid device consisting of a reflective LCD and an OLED were addressed and solved. With suitable design of the process flow, electrical and optical characteristics of the OLED were not affected by the following LCD processes. Storage lifetime of this TR-hybrid device was even longer than that of the control one because of the passivation effect of the LC materials.Contents 要 ibstract iiontents ivable captions: viiigure captions: viiihapter 1 1.1 Contrast ratio (CR) and ambient contrast ratio (A-CR) of a display 3.2 Introduction to OLED and LCD 5.2.1 Organic light-emitting device 6.2.2 Liquid crystal display 8.3 High ambient contrast OLED 11.4 Hybrid Emi-flective device (OLED combined with LCD) 15.5 Thesis organization 18eference 23hapter 2 27.1 Introduction 27.2 Fabrication of OLED 28.2.1 Evaporator 28.2.2 OLED and monolayer device 29.3 Measurement of organic thin film and OLED 31.3.1 B-J-V characteristics of OLED, J-V of organic thin film, and photocurrent measurements 31.3.2 Optical measurements: PL, Transmittance and Reflectance 33.3.3 Morphological measurements (FE-SEM, AFM, SOPRA) 35.4 LCD fabrication and measurements 36eferences 45hapter 3 46.1 Introduction 46.2 Ag Dopant 49.2.1 Appearance of thin-films 49.2.2 Morphology: FE-SEM and AFM 50.2.3 Optical properties: refractive index n(λ) and absorption coefficient k(λ) 52.2.4 Optical analysis: transmittance, reflectance and absorptance 53.2.5 Photoluminescence characteristics 56.2.6 Electrical characteristics of mono-layer device 58.2.7 Photosensitivity 60eference 74hapter 4 76.1 Introduction 76.2 Results of A series 77.2.1 Architecture of ADIBC-OLED 77.2.2 Results and discussions 78.3.1 Architecture and fabrication 82.3.2 Results and discussions 83.3.3 Results and discussion for A-CR and wide view angle reflectance 87eference 110hapter 5 111.1 Introduction 111.2 Experimental details (fabrication for transparent OLED and the TR-hybrid device) 113.2.1 Transparent OLED fabrication 113.2.2 Fabrication process for TR-hybrid device 113.3 Results and discussions 116.3.1 Characteristics of DML for transparent OLED 116.3.2 Variation of transparent OLED characteristics during fabrication 116.3.3 Optical characteristics of TR-hybrid device 118.4 Operational mechanism and Storage lifetime for hybrid device 121eference 132hapter 6 133.1 Summary 133.2 Further works 135eference 138ppendix A 139.1 Introduction: 139.2 Organic material: 141.2.1 Chemical structure 141.2.2 Absorptance spectrum 143.3.1 Absorption characterizations 144.3.2 Photoluminescence 144.3.3 Photocurrent measurement 146eference 152ppendix B 153eference 158ppendix C 159eference 165ppendix D 166.1. High transparent OLED structure and characterization 167.2. Conceptual structure of tandem device 168.3 Simulated A-CR results 169.4 Operational mechanisms and white light A-CR 172eferences 17