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71.
72.
Hunhee Lim Donghun Kim Min‐Jae Choi Edward H. Sargent Yeon Sik Jung Jin Young Kim 《Liver Transplantation》2019,9(48)
Quantum‐dot (QD) photovoltaics (PVs) offer promise as energy‐conversion devices; however, their open‐circuit‐voltage (VOC) deficit is excessively large. Previous work has identified factors related to the QD active layer that contribute to VOC loss, including sub‐bandgap trap states and polydispersity in QD films. This work focuses instead on layer interfaces, and reveals a critical source of VOC loss: electron leakage at the QD/hole‐transport layer (HTL) interface. Although large‐bandgap organic materials in HTL are potentially suited to minimizing leakage current, dipoles that form at an organic/metal interface impede control over optimal band alignments. To overcome the challenge, a bilayer HTL configuration, which consists of semiconducting alpha‐sexithiophene (α‐6T) and metallic poly(3,4‐ethylenedioxythiphene) polystyrene sulfonate (PEDOT:PSS), is introduced. The introduction of the PEDOT:PSS layer between α‐6T and Au electrode suppresses the formation of undesired interfacial dipoles and a Schottky barrier for holes, and the bilayer HTL provides a high electron barrier of 1.35 eV. Using bilayer HTLs enhances the VOC by 74 mV without compromising the JSC compared to conventional MoO3 control devices, leading to a best power conversion efficiency of 9.2% (>40% improvement relative to relevant controls). Wider applicability of the bilayer strategy is demonstrated by a similar structure based on shallow lowest‐unoccupied‐molecular‐orbital (LUMO) levels. 相似文献
73.
Jaeho Shin Dong Shin Choi Hyeon Jeong Lee Yousung Jung Jang Wook Choi 《Liver Transplantation》2019,9(14)
Aqueous zinc ion batteries (AZIBs) are steadily gaining attention based on their attractive merits regarding cost and safety. However, there are many obstacles to overcome, especially in terms of finding suitable cathode materials and elucidating their reaction mechanisms. Here, a mixed‐valence vanadium oxide, V6O13, that functions as a stable cathode material in mildly acidic aqueous electrolytes is reported. Paired with a zinc metal anode, this material exhibits performance metrics of 360 mAh g?1 at 0.2 A g?1, 92% capacity retention after 2000 cycles, and 145 mAh g?1 at a current density of 24.0 A g?1. A combination of experiments and density functional theory calculations suggests that hydrated intercalation, where water molecules are cointercalated with Zn ions upon discharge, accounts for the aforementioned electrochemical performance. This intercalation mechanism facilitates Zn ion diffusion throughout the host lattice and electrode–electrolyte interface via electrostatic shielding and concurrent structural stabilization. Through a correlation of experimental data and theoretical calculations, the promise of utilizing hydrated intercalation as a means to achieve high‐performance AZIBs is demonstrated. 相似文献
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Jungil Yang Lae‐Hyeon Cho Jinmi Yoon Hyeryung Yoon Antt Htet Wai Woo‐Jong Hong Muho Han Hitoshi Sakakibara Wanqi Liang Ki‐Hong Jung Jong‐Seong Jeon Hee‐Jong Koh Dabing Zhang Gynheung An 《Plant biotechnology journal》2019,17(1):178-187
Grain number is an important agronomic trait. We investigated the roles of chromatin interacting factor Oryza sativa VIN3‐LIKE 2 (OsVIL2), which controls plant biomass and yield in rice. Mutations in OsVIL2 led to shorter plants and fewer grains whereas its overexpression (OX) enhanced biomass production and grain numbers when compared with the wild type. RNA‐sequencing analyses revealed that 1958 genes were up‐regulated and 2096 genes were down‐regulated in the region of active division within the first internodes of OX plants. Chromatin immunoprecipitation analysis showed that, among the downregulated genes, OsVIL2 was directly associated with chromatins in the promoter region of CYTOKININ OXIDASE/DEHYDROGENASE2 (OsCKX2), a gene responsible for cytokinin degradation. Likewise, active cytokinin levels were increased in the OX plants. We conclude that OsVIL2 improves the production of biomass and grain by suppressing OsCKX2 chromatin. 相似文献
78.
Won‐Jun Jang Sung Keun Jung Tam Thuy Lu Vo Chul‐Ho Jeong 《Journal of cellular and molecular medicine》2019,23(2):1106-1115
The concept of drug repositioning has recently received considerable attention in the field of oncology. In the present study, we propose that paroxetine can be used as a potent anticancer drug. Paroxetine, one of the selective serotonin reuptake inhibitors (SSRIs), has been widely prescribed for the treatment of depression and anxiety disorders. Recently, SSRIs have been reported to have anticancer activity in various types of cancer cells; however, the underlying mechanisms of their action are not yet known. In this study, we investigated the potential anticancer effect of paroxetine in human colorectal cancer cells, HCT116 and HT‐29. Treatment with paroxetine reduced cell viability, which was associated with marked increase in apoptosis, in both the cell lines. Also, paroxetine effectively inhibited colony formation and 3D spheroid formation. We speculated that the mode of action of paroxetine might be through the inhibition of two major receptor tyrosine kinases – MET and ERBB3 – leading to the suppression of AKT, ERK and p38 activation and induction of JNK and caspase‐3 pathways. Moreover, in vivo experiments revealed that treatment of athymic nude mice bearing HT‐29 cells with paroxetine remarkably suppressed tumour growth. In conclusion, paroxetine is a potential therapeutic option for patients with colorectal cancer. 相似文献
79.
Jeongjoo Lee You‐Hyun Seo Sung‐Nam Kwon Do‐Hyung Kim Seokhoon Jang Hyeonwoo Jung Youngu Lee Hasitha Weerasinghe Taehyo Kim Jin Young Kim Doojin Vak Seok‐In Na 《Liver Transplantation》2019,9(36)
The record efficiency of the state‐of‐the‐art polymer solar cells (PSCs) is rapidly increasing, due to the discovery of high‐performance photoactive donor and acceptor materials. However, strong questions remain as to whether such high‐efficiency PSCs can be produced by scalable processes. This paper reports a high power conversion efficiency (PCE) of 13.5% achieved with single‐junction ternary PSCs based on PTB7‐Th, PC71BM, and COi8DFIC fabricated by slot‐die coating, which shows the highest PCE ever reported in PSCs fabricated by a scalable process. To understand the origin of the high performance of the slot‐die coated device, slot‐die coated photoactive films and devices are systematically investigated. These results indicate that the good performance of the slot‐die PSCs can be due to a favorable molecule‐structure and film‐morphology change by introducing 1,8‐diiodooctane and heat treatment, which can lead to improved charge transport with reduced carrier recombination. The optimized condition is then used for the fabrication of large‐area modules and also for roll‐to‐roll fabrication. The slot‐die coated module with 30 cm2 active‐area and roll‐to‐roll produced flexible PSC has shown 8.6% and 9.6%, respectively. These efficiencies are the highest in each category and demonstrate the strong potential of the slot‐die coated ternary system for commercial applications. 相似文献
80.
Suitability of tomato leaves for larval development of Potato Tuber Moth,Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) 总被引:1,自引:0,他引:1
The potato tuber moth (PTM) is an important pest of the potato plant and its tuber. With the expansion of its geographic range, the PTM could be potential threat to the tomato (Solanum lycopersicum L.), a congeneric species of the potato. To assess that risk, we tested larval feeding and development of PTM on leaves of five cultivated tomato varieties namely Moneymaker, Campari, Ailsa Craig, LA3475, E6203 and one wild tomato variety S. pimpinellifolium. PTM larvae accepted all tested plant leaves and developed into adults. Larval development was fastest on the Ailsa Craig variety. Pupae developed fastest on the Moneymaker variety and slowest on LA3475. Host acceptance and survival were highest on Ailsa Craig and lowest on LA3475. The significantly highest male proportion occurred on LA3475 variety. The study showed that PTM could be a potential threat to tomato cultivation which is rapidly increasing in temperate regions owing to climate change. 相似文献