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排序方式: 共有943条查询结果,搜索用时 15 毫秒
931.
Seungnyeong Heo Jonghwi Baek Juhyun Bae Prof. Dr. Bo Am Seo Seongjun Kim Subin Jeong Suhyun Kim Dr. Yiseul Ryu Prof. Dr. Joong-jae Lee 《Chembiochem : a European journal of chemical biology》2023,24(11):e202200700
Horseradish peroxidase (HRP) is a pivotal biocatalyst for biosensor development and fine chemical synthesis. HRP proteins are mostly extracted and purified from the roots of horseradish because the solubility and productivity of recombinant HRP in bacteria are significantly low. In this study, we investigate the reconstitution system of split HRP fragments to improve its soluble expression levels in E. coli allowing the cost-effective production of bioactive HRPs. To promote the effective association between two HRP fragments (HRPn and HRPc), we exploit SpyTag-SpyCatcher chemistry, a versatile protein coupling method with high affinity and selectivity. Each HRP fragment was genetically fused with SpyTag and SpyCatcher, respectively, exhibiting soluble expression in the E. coli cytoplasm. The engineered split HRPs were effectively and irreversibly reconstituted into a biologically active and stable assembly that can catalyze intrinsic enzymatic reactions. Compared to the chaperone co-expression system, our approach shows that the production yield of soluble HRP is comparable, but the purity of the final product is relatively high. Therefore, our results can be applied to the high-yield production of recombinant HRP variants and other difficult-to-express proteins in bacteria without complex downstream processes. 相似文献
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Renewable energy generation cannot be consistently predicted or controlled. Therefore, it is currently not widely used in the electricity market, which requires dependable production. In this study, reliability- and variance-based controls of energy storage strategies are proposed to utilize renewable energy as a steady contributor to the electricity market. For reliability-based control, photovoltaic (PV) generation is assumed to be registered in the power generation plan. PV generation yields a reliable output using energy storage units to compensate for PV prediction errors. We also propose a runtime state-of-charge management method for sustainable operations. With variance-based controls, changes in rapid power generation are limited through ramp rate control. This study introduces new reliability and variance indices as indicators for evaluating these strategies. The reliability index quantifies the degree to which the actual generation realizes the plan, and the variance index quantifies the degree of power change. The two strategies are verified based on simulations and experiments. The reliability index improved by 3.1 times on average over 21 days at a real power plant. 相似文献
935.
Food Science and Biotechnology - The article “Food-derived coagulase-negative Staphylococcus as starter cultures for fermented foods”, written by Sojeong Heo, Jong-Hoon Lee, and Do-Won... 相似文献
936.
In the last few years, convolutional neural networks (CNNs) have demonstrated good performance while solving various computer vision problems. However, since CNNs exhibit high computational complexity, signal processing is performed on the server side. To reduce the computational complexity of CNNs for edge computing, a lightweight algorithm, such as a MobileNet, is proposed. Although MobileNet is lighter than other CNN models, it commonly achieves lower classification accuracy. Hence, to find a balance between complexity and accuracy, additional hyperparameters for adjusting the size of the model have recently been proposed. However, significantly increasing the number of parameters makes models dense and unsuitable for devices with limited computational resources. In this study, we propose a novel MobileNet architecture, in which the number of parameters is adaptively increased according to the importance of feature maps. We show that our proposed network achieves better classification accuracy with fewer parameters than the conventional MobileNet. 相似文献
937.
We designed a rhodamine B-based colorimetric chemosensor BHSO ((Z)-3′,6′-bis(diethylamino)-2-(2-(((8-hydroxy-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)methylene)amino)ethyl)spiro[isoindoline-1,9′-xanthen]-3-one) for detecting Cu2+. In the presence of Cu2+, BHSO caused a colour variation from colourless to bright orange. The limit of detection for Cu2+ towards BHSO was 0.73 μM. The binding of BHSO to Cu2+ was analysed as a 1:1 ratio through a Job plot and electrospray ionisation mass spectrometry. BHSO can detect readily Cu2+ with a test strip by colorimetric variation. The detecting process of Cu2+ by BHSO was represented by ultraviolet-visible titration, electrospray ionisation mass spectrometry, proton nuclear magnetic resonance titration, Job plot and density functional theory calculations. 相似文献
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939.
Atif Jan Thomas Rembert Sunil Taper Joanna Symonowicz Nives Strkalj Taehwan Moon Yun Seong Lee Hagyoul Bae Hyun Jae Lee Duk-Hyun Choe Jinseong Heo Judith MacManus-Driscoll Bartomeu Monserrat Giuliana Di Martino 《Advanced functional materials》2023,33(22):2214970
Ferroelectric materials offer a low-energy, high-speed alternative to conventional logic and memory circuitry. Hafnia-based films have achieved single-digit nm ferroelectricity, enabling further device miniaturization. However, they can exhibit nonideal behavior, specifically wake-up and fatigue effects, leading to unpredictable performance variation over consecutive electronic switching cycles, preventing large-scale commercialization. The origins are still under debate. Using plasmon-enhanced spectroscopy, a non-destructive technique sensitive to <1% oxygen vacancy variation, phase changes, and single switching cycle resolution, the first real-time in operando nanoscale direct tracking of oxygen vacancy migration in 5 nm hafnium zirconium oxide during a pre-wake-up stage is provided. It is shown that the pre-wake-up leads to a structural phase change from monoclinic to orthorhombic phase, which further determines the device wake-up. Further migration of oxygen ions in the phase changed material is then observed, producing device fatigue. These results provide a comprehensive explanation for the wake-up and fatigue with Raman, photoluminescence and darkfield spectroscopy, combined with density functional theory and finite-difference time-domain simulations. 相似文献
940.
Dong Hyuk Youn Ngoc Minh Tran Thanh Nhan Nguyen Sung Min Cho Harry Jung Aran Lee Jinhee Kim Nayoung Kim Jin Pyeong Jeon Hyojong Yoo 《Journal of the American Ceramic Society》2023,106(12):7218-7229
The design and optimization of nanostructures with unique morphologies and properties are at the forefront of biomedical nanotechnology. Cerium oxides are widely used to investigate the effect of morphology on performance. However, elucidating the morphology–activity relationship of cerium oxide nanocrystals in biomedical applications remains challenging. Herein, the therapeutic effects of cerium oxide nanoparticles with different morphologies: cerium oxide nanorods with two different aspect ratios (CeOx NRs_A and CeOx NRs_B), cerium oxide nanopolyhedra (CeOx NPs), and cerium oxide nanocubes (CeOx NCs) are investigated in in vivo and in vitro mild traumatic brain injury (TBI) models. Cerium oxide nanoparticles inhibit oxidative stress and inflammation after mild TBI, alleviating cognitive impairment; furthermore, the therapeutic effect is significantly affected by their morphology. Owing to the higher Ce3+/Ce4+ ratio, exposure of more active crystal surfaces, and greater number of exposed oxygen vacancies, CeOx NRs show better activity than CeOx NPs and CeOx NCs for mild TBI. Among the two investigated types of cerium oxide nanorods, CeOx NRs_A, with a higher Ce3+/Ce4+ ratio on the surface, appear to spread better than CeOx NRs_B in the injured lesions. The factors causing morphology-controlled biomedical performance, such as Ce3+/Ce4+ molar ratio, surface area, and aspect ratio, are discussed. 相似文献