Molecular Propulsion: Chemical Sensing and Chemotaxis of DNA Driven by RNA Polymerase

Yu, Hua,Jo, Kyubong,Kounovsky, Kristy L.,Pablo, Juan J. de,Schwartz, David C. American Chemical Society 2009 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.131 No.16

<P>Living cells sense extracellular signals and direct their movements in response to stimuli in environment. Such autonomous movement allows these machines to sample chemical change over a distance, leading to chemotaxis. Synthetic catalytic rods have been reported to chemotax toward hydrogen peroxide fuel. Nevertheless individualized autonomous control of movement of a population of biomolecules under physiological conditions has not been demonstrated. Here we show the first experimental evidence that a molecular complex consisting of a DNA template and associating RNA polymerases (RNAPs) displays chemokinetic motion driven by transcription substrates nucleoside triphosphates (NTPs). Furthermore this molecular complex exhibits a biased migration into a concentration gradient of NTPs, resembling chemotaxis. We describe this behavior as 'Molecular Propulsion', in which RNAP transcriptional actions deform DNA template conformation engendering measurable enhancement of motility. Our results provide new opportunities for designing and directing nanomachines by imposing external triggers within an experimental system.</P>

Investigation of a new 3Y-stabilized zirconia with an improved optical property for applications as a dental ceramic

Yuhua Wang,Hui Huang,Limin Gao and,Fuqiang Zhang 한양대학교 세라믹연구소 2011 Journal of Ceramic Processing Research Vol.12 No.4

To study the mechanical and optical properties of a new nanocrystalline yttria-stabilized zirconia (PX242A Tosoh Japan). The influence of heating rates on its properties and its potential use as a dental ceramic were also evaluated. Samples of PX242A were divided into 4 groups according to heating rates : group H1 (100oKh−1); group H2 (200oKh−1); group H4 (400oKh−1);group H6 (600oKh−1). Group H0 (3Y-SBE Tosoh Japan) was made according to the manufacturer’s recommendation as a control. The contrast ratio (CR), transparency parameter (TP) and total transmittance (TT) were measured by an Xrite spectrophotometer. The flexural strength and fracture toughness were also evaluated. The flexural strength and fracture toughness were found to be independent of the heating rate while the optical properties significantly increased when the heating rates were 600oKh−1, 200oKh−1 and 400oKh−1, but were not significantly different with 100oKh−1. A heating rate of 600oKh−1 is suggested as a time efficiency protocol, because it could provide desirable mechanical and optical properties,making zirconia suitable for clinical use.

Fermented Platycodon grandiflorum Extract Inhibits Lipid Accumulation in 3T3-L1 Adipocytes and High-Fat Diet-Induced Obese Mice

Yuhua Huang,정다운,이옥환,강일준 한국식품영양과학회 2016 Journal of medicinal food Vol.19 No.11

The aim of this study was to investigate whether fermented Platycodon grandiflorum (FPG) inhibits lipid accumulation in 3T3-L1 adipocytes and mice with high-fat diet (HFD)-induced obesity. We evaluated the effect of FPG on antiadipogenic activity via regulation of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα), as well as protein expression of their target genes, fatty acid binding protein 4 (FABP4). We further examined the antiobesity effects of FPG on HFD-induced obesity in mice. The FPG was orally administered to mice with a HFD at 50, 100, or 200 mg/kg/day for 8 weeks. Our results show that FPG significantly inhibited fat accumulation during 3T3-L1 adipogenesis through downregulating adipogenic transcript factors. Moreover, FPG markedly reduced the final body weight with a decrease in epididymal adipose tissue mass and adipocyte size compared with the untreated HFD-induced group. The effects of FPG on HFD-induced obesity were primarily responsible for inhibiting adipogenesis in adipose tissue and regulating lipid metabolism, such as through lipogenesis and fatty acid oxidation. Additionally, FPG ameliorated serum total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels. Hence, FPG may be an alternative treatment for controlling obesity through downregulating lipid accumulation.

Adaptive Synchronization of the Complex Dynamical Network with Double Non-delayed and Double Delayed Coupling

Yuhua Xu,Wuneng Zhou,Jian-an Fang 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.2

To simulate more realistic networks, we introduce a complex dynamical network model with double non-delayed and double delayed coupling and further investigate its synchronization phenomenon in this paper. Based on Lyapunov stability theory, adaptive synchronization criteria is obtained. Analytical result shows that under the designed adaptive controllers, the complex dynamical network with double non-delayed and double delayed coupling can asymptotically synchronize to a given trajectory. What is more, the coupling matrix is not assumed to be symmetric or irreducible. Finally, simulation results show the method is effective.

Back-stepping Robust Control for Flexible Air-breathing Hypersonic Vehicle via a-filter-based Uncertainty and Disturbance Estimator

Yuhua Yang,Xingling Shao,Yi Shi,Wendong Zhang 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.2

In this paper, a robust control scheme using back-stepping and α-filter-based uncertainty and disturbance estimator (UDE) is designed for flexible air-breathing hypersonic vehicle (FAHV) in the presence of severe external disturbances. Firstly, with the aid of back-stepping technique, the longitudinal dynamics of FAHV is separated into velocity and altitude subsystems. Feedback linearization (FL) is utilized to design control laws for each subsystem. Secondly, to enhance robustness of the controller, α-filter-based UDEs are constructed to estimate the lumped disturbances, including aerodynamic parameter uncertainties, flexible effects and external disturbances. More importantly, the performance superiority of α-filter-based UDE is clarified via frequency response analysis and comparisons with an extended state observer (ESO). Furthermore, the issue of tuning design parameter α is analyzed. The stability of closed-loop system is proved by Lyapunov stability theory. Simulation results demonstratethe effectiveness of the proposed control strategy.

The Impact of Linguistic and Cultural Differences on Chinese-English Translation

Yuhua Gao 한국영어교육연구학회 2012 영어교육연구 Vol.- No.44

We all agree that translation is cross-cultural communication, which is not only the linguistic transfer but also cultural exchange. Translation is the exploration of an unbridgeable gap and of a tension between cultures, and its function is to develop cross-cultural communication and bridge the gap. Moreover, no translators could afford to neglect lots of striking differences between the two languages, namely English and Chinese. In this essay, the author will explore the impact of the sharp contrast between English and Chinese on translation from two perspectives as follows: Linguistic forms and cultural differences. In terms of linguistic forms, English is subject-prominent, hypotaxis, agglutinating, pitch language, whereas Chinese is topic-prominent, parataxis, isolating, tone language. Furthermore, they also differ a lot in word order and syntactic structures. As for different way of thinking, Eastern thinking patterns are characterized by entirety, synthesis, specificity and parataxis. Conversely, when it come to the westerners, analysis, logic, abstractness, linear-thinking come first.

Interleukin-10-Producing B Cells Help Suppress Ovariectomy-Mediated Osteoporosis

Yuhua Wang,Wei Zhang,임성민,Li Xu,진준오 대한면역학회 2020 Immune Network Vol.20 No.6

Osteoporosis is prevalent in elderly women and it may cause dental implant failure. In particular, estrogen deficiency in postmenopausal women leads to higher rates of osteoporosis prevalence. Immune cell-mediated effects involving the development of osteoporosis have been studied previously; however, the role of IL-10-producing regulatory B (B10) cells in osteoporosis is largely unclear. Here, we examined the role of B10 cells in osteoporosis. C57BL/6 mice were subjected to ovariectomy (OVX). Fifteen weeks after OVX surgery, the first molar of the right maxillary was extracted, and twenty-four weeks after OVX surgery, serous progression of osteoporosis was observed in the alveolar bone. Moreover, the proportion of CD19+CD5+CD1dhigh regulatory B cells, B10, and CD4+CD25+FoxP3+ regulatory T cells from the spleen of OVX mice decreased during the progression of osteoporosis, compared to controls. In contrast to regulatory cells, IL-17-producing Th (Th17) cell levels were increased in OVX mice. Adoptive transfer of B10 cells to OVX mice led to a decrease in Th17 cell abundance and inhibited the development of osteoporosis in the alveolar bone from OVX mice. Thus, our results suggest that B10 cells may help suppress osteoporosis development.

APPLICATION OF PSEUDO $Z_p$ INDEX THEORY TO PERIODIC SOLUTIONS WITH MINIMAL PERIOD FOR DISCRETE HAMILTONIAN SYSTEMS

Yuhua, Long The Korean Society for Computational and Applied M 2010 Journal of applied mathematics & informatics Vol.28 No.3

By making use of minimax theory and pseudo $Z_p$ index theory, some results on the existence and multiplicity of periodic solutions with minimal period to nonconvex superquadratic discrete Hamiltonian systems are obtained.

Performance of a Polymeric Light-Emitting Diode (PLED) Using a ZnO Film as an Anode Electrode

Yuhua Lee,S. H. Huang 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.2

An ion-beam sputtering technique was utilized in ZnO film deposition, and small and large ion-beam currents (Ib) of 10 and 30 mA, respectively, were used with the ion-beam voltage (Vb) kept constant at 600 V. To control the thin film's stoichiometry and, thus, its resistivity, we employed different oxygen flow rates (r) of 0, 0.2, 0.4, 0.6 and 1 sccm. For both Ib = 10 and 30 mA, the resistivity increased and the carrier concentration decreased with increasing oxygen flow rates. When the carrier concentration dropped below 1020 cm-3, the performance of the PLED was degraded, and no illumination was given off when the concentration reached ∽1017 cm-3. The best device performance observed for the films made with Ib = 10 mA and 30 mA corresponded, respectively, to no oxygen flow rate and a small (0.2 sccm) ow rate. These two lms showed a luminance of ∽1600 cd/m2 at 10 V. The turn-on voltage was 3.0 V for Ib = 10 mA and 4.5 V for Ib = 30 mA. An ion-beam sputtering technique was utilized in ZnO film deposition, and small and large ion-beam currents (Ib) of 10 and 30 mA, respectively, were used with the ion-beam voltage (Vb) kept constant at 600 V. To control the thin film's stoichiometry and, thus, its resistivity, we employed different oxygen flow rates (r) of 0, 0.2, 0.4, 0.6 and 1 sccm. For both Ib = 10 and 30 mA, the resistivity increased and the carrier concentration decreased with increasing oxygen flow rates. When the carrier concentration dropped below 1020 cm-3, the performance of the PLED was degraded, and no illumination was given off when the concentration reached ∽1017 cm-3. The best device performance observed for the films made with Ib = 10 mA and 30 mA corresponded, respectively, to no oxygen flow rate and a small (0.2 sccm) ow rate. These two lms showed a luminance of ∽1600 cd/m2 at 10 V. The turn-on voltage was 3.0 V for Ib = 10 mA and 4.5 V for Ib = 30 mA.

The Impact of Agreement on the Licensing of Null Arguments

Yuhua Gao,Lirong Ding 한국영어교육연구학회 2015 영어교육연구 Vol.- No.47

This paper attempts to illustrate the impact of agreement on the licensing of null arguments, especially on pro and argument ellipsis (henceforth AE) in Italian, Turkish, Serbo-Croatian (henceforth SC) and Mandarin Chinese (henceforth MC). Subject pros in agreement pro-drop languages like Italian and Turkish, and object pros in SC, are supposed to be licensed by subject or object-predicate agreement. By contrast, I argue, in radical pro-drop languages without agreement at all like MC, subject pro is licensed by discourse and context, along with the definiteness restriction on the pre-verbal subject position. Moreover, I further argue that invariant nominal gender prohibits the licensing of AE in SC, a NP language with rich agreement within Traditional Noun Phrase (henceforth TNP).