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141.
A mechanosensitive, visco‐poroelastic polymer ion pump that can rapidly establish a dense electrical double layer via mechanical pressure, thereby significantly enhancing output performance of an ionic triboelectric nanogenerator (iTENG), is described. A working mechanism of an iTENG using a highly mechanosensitive, visco‐poroelastic ion pump is suggested and the optimal characteristics of the polymer ion pump are reported by investigating optical, mechanical, electrical, and electrochemical properties. Surprisingly, the pressure sensitivity of the iTENG reaches 23.3 V kPa?1, which is tens of times the record value. To achieve controlled high‐frequency pulses from an iTENG, kinematic systems using a gear train and a cam are integrated with a single grounded iTENG, which produces a maximum of 600 V and 22 mA (≈2.2 W cm?2) at an input frequency of 1.67 Hz; after power transforming, those values are converted to 1.42 V and 225 mA. A capacitor of 1 mF can be fully charged to 2 V in only 60 s, making it possible to continuously operate a wireless‐communicating self‐powered humidity sensor. Also, due to the high transparency and deformability of the polymer ion pump, a self‐powered transparent tactile sensor is successfully assembled using a 5 × 5 iTENG array.  相似文献   
142.
Recently, two‐dimensional (2D) structure on three‐dimensional (3D) perovskites (graded 2D/3D) has been reported to be effective in significantly improving both efficiency and stability. However, the electrical properties of the 2D structure as a passivation layer on the 3D perovskite thin film and resistance to the penetration of moisture may vary depending on the length of the alkyl chain. In addition, the surface defects of the 2D itself on the 3D layer may also be affected by the correlation between the 2D structure and the hole conductive material. Therefore, systematic interfacial study with the alkyl chain length of long‐chained alkylammonium iodide forming a 2D structure is necessary. Herein, the 2D interfacial layers formed are compared with butylammonium iodide (BAI), octylammonium iodide (OAI), and dodecylammonium iodide (DAI) iodide on a 3D (FAPbI3)0.95(MAPbBr3)0.05 perovskite thin film in terms of the PCE and humidity stability. As the length of the alkyl chain increased from BA to OA to DA, the electron‐blocking ability and humidity resistance increase significantly, but the difference between OA and DA is not large. The PSC post‐treated with OAI has slightly higher PCE than those treated with BAI and DAI, achieving a certified stabilized efficiency of 22.9%.  相似文献   
143.
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   
144.
The soybean pod borer, Maruca vitrata is one of the key insect pests of tropical legumes. It damages tender leaf axils, flower buds, flowers and pods by webbing and boring clusters of flowers and pods. In this study, we investigated the survival and life table parameters of M. vitrata on several leguminous crops; soybean (cvs. Daewon, Poongsannamool and Socheongja), azuki bean (cv. Hongeon), mung bean (cv. Sanpo), and cowpea (cv. Jangchae), compared to artificial diet to assess the antibiosis resistance to M. vitrata. The life‐variables of M. vitrata were significantly affected by the tested legume cultivars. None of the larvae fed cowpea cultivar Jangchae survived. The azuki bean cultivar Hongeon and mung bean cultivar Sanpo were found susceptible to M. vitrata, whereas cowpea cultivar Jangchae and soybean cultivar Daewon showed antibiosis resistance to M. vitrata. Further studies should examine the chemicals associated with leguminous crop cultivars and its mechanism to develop a control method against M. vitrata.  相似文献   
145.
Anastatus orientalis is a solitary endoparasitoid of Lycorma delicatula (Hemiptera: Fulgoridae) eggs. We investigated the development, longevity, fecundity, and sex ratio of A. orientalis on different temperatures to establish the optimal temperature condition for laboratory mass rearing. There were significant differences in its development and longevity between 15 °C and the rest of temperature conditions (20, 25, and 30 °C), among which were no significant differences. The average number of eggs laid by A. orientalis was higher at 20 and 25 °C, but there was no statistically significant difference in its fecundity between the two temperatures. More females emerged at 15 and 20 °C than higher temperatures.Parasitisms of A. orientalis varied with host egg ages and densities. Even in 14 day old eggs of L. delicatula, parasitoids successfully emerged from 92.3% of the parasitized eggs. On the other hand, parasitism was lowest (13.8%) on just before hatching eggs. Parasitism was negatively dependent on host density.Oviposition behavior for A. orientalis primarily occurred at 1400–1600 h, not at 2400–0800 h. The majority of this parasitoid's emergence occurred at 0800–1000 h, largely before noon. These results may be useful for controlling the adequate time for supplying host eggs and release density of this parasitoid as well as for potentially predicting the accurate time for securing parasitoid adults in laboratory mass rearing of A. orientalis.  相似文献   
146.
147.
Leucyl-tRNA synthetase (LRS) plays an important role in amino acid-dependent mTORC1 signaling, which is known to be associated with cellular metabolism and proliferation. Therefore, LRS-targeting small molecules that can suppress mTORC1 activation may provide an alternative strategy to current anticancer therapy. In this work, we developed a library of leucyladenylate sulfate analogues by extensively modifying three different pharmacophoric regions comprising adenine, ribose and leucine. Several effective compounds were identified by cell-based mTORC1 activation assays and further tested for anticancer activity. The selected compounds mostly exhibited selective cytotoxicity toward five different cancer cell lines, supporting the hypothesis that the LRS-mediated mTORC1 pathway is a promising alternative target to current therapeutic approaches.  相似文献   
148.
Journal of Industrial Microbiology & Biotechnology - Methylated flavonoids possess improved bioactivities compared to their unmethylated counterparts. In this study, for the efficient...  相似文献   
149.
Kim  Ji Yoon  Joo  Gea-Jae 《Limnology》2019,20(1):3-11
Limnology - Maintaining moderate levels of aquatic plant cover in agricultural reservoirs is an important issue because aquatic plant development is closely related to diverse ecosystem functions,...  相似文献   
150.
Sleep and Biological Rhythms - There is an increasing need for portable sleep monitoring in clinical practice, but there is no comparative study that used the same device for home and in-laboratory...  相似文献   
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