Maydis Stigma Elicits Analgesia and Blocks Edema in Mice and Inhibits Inflammation in Macrophages

Jeong, Yun Hee,Oh, You-Chang,Cho, Won-Kyung,Yang, Hye Jin,Ma, Jin Yeul World Scientific Publishing Company 2017 The American journal of Chinese medicine Vol.45 No.7

<P>Maydis Stigma (MS) is an herb traditionally used in many parts of the world. Previous studies have reported that MS plays a role in several biological activities, including antidiabetic and anticancer activities. However, the effects of a MS ethanolic extract (MSE) on the anti-inflammatory cellular mechanism remain unclear. Here, we investigated the anti-inflammatory properties of MSE and its molecular mechanism both <I>in vitro</I> and <I>in vivo</I>. The effects of MSE on the production of inflammatory mediators, cytokines, and related proteins and the identification of target genes were determined using LPS-stimulated macrophages. We also determined the analgesic and anti-inflammatory effects of MSE by examining acetic acid-induced writhing responses and xylene-induced ear edema in mice. Our results indicated that MSE markedly decreased iNOS and COX-2 levels without causing cytotoxicity and suppressed the secretion of NO in LPS-stimulated macrophages. MSE also inhibited the production of proinflammatory cytokines, such as TNF-<TEX>$ \alpha $</TEX>, IL-6, and IL-1<TEX>$ \beta $</TEX>, and induced the expression of HO-1. Moreover, MSE treatment significantly reduced the LPS-stimulated activation of MAPK, NF-<TEX>$ \kappa $</TEX>B, and AP-1. Furthermore, MSE exerted an analgesic effect on the acetic acid-induced abdominal writhing response test and an anti-inflammatory effect on xylene-induced ear edema in ICR mice. Finally, we investigated the components of MSE using UPLC-ESI-MS and found that it contains the maysin as a marker component. Overall, these observations demonstrate that MSE has anti-inflammatory and antinociceptive effects both <I>in vitro</I> and <I>in vivo</I>, which may provide new scientific evidence for its use as a potential therapeutic agent for the treatment of inflammation.</P>

Development of a Tele-Operated Rescue Robot for a Disaster Response

Hong, Seongil,Park, Gyuhyun,Lee, Youngwoo,Lee, Wonsuk,Choi, Byunghun,Sim, Okkee,Oh, Jun-Ho World Scientific Publishing Company 2018 INTERNATIONAL JOURNAL OF HUMANOID ROBOTICS Vol.15 No.4

<P>This paper proposes practical hardware design strategies and control methods for a rescue robot to save patients in disastrous environments. None of the existing humanoid robots have not shown the capability to efficiently execute rescue tasks for transferring a human to a safe place in a highly unstructured world. To resolve this problem a new form of powerful dual arm mechanism and hybrid tracked-legged mobile platform is developed and the motion is synthesized with dynamics based optimization and a modified hierarchical control scheme. These new design and control policies enable us to simultaneously enhance the manipulation performance and driving stability which have been verified through both in extensive numerical simulations and physical experiments where the rescue robot and whole-body control are indeed required.</P>

MULTIFRACTAL CHARACTERISTICS OF AXISYMMETRIC JET TURBULENCE INTENSITY FROM RANS NUMERICAL SIMULATION

SEO, YONGWON,KO, HAENG SIK,SON, SANGYOUNG WORLD SCIENTIFIC PUBLISHING COMPANY 2018 FRACTALS -LONDON- Vol.26 No.1

<P>A turbulent jet bears diverse physical characteristics that have been unveiled yet. Of particular interest is to analyze the turbulent intensity, which has been a key factor to assess and determine turbulent jet performance since diffusive and mixing conditions are largely dependent on it. Multifractal measures are useful in terms of identifying characteristics of a physical quantity distributed over a spatial domain. This study examines the multifractal exponents of jet turbulence intensities obtained through numerical simulation. We acquired the turbulence intensities from numerical jet discharge experiments, where two types of nozzle geometry were tested based on a Reynolds-Averaged Navier-Stokes (RANS) equations. The <TEX>$ k$</TEX>-<TEX>$ \varepsilon $</TEX> model and <TEX>$ k$</TEX>-<TEX>$ \omega $</TEX> model were used for turbulence closure models. The results showed that the RANS model successfully regenerates transversal velocity profile, which is almost identical to an analytical solution. The RANS model also shows the decay of turbulence intensity in the longitudinal direction but it depends on the outfall nozzle lengths. The result indicates the existence of a common multifractal spectrum for turbulence intensity obtained from numerical simulation. Although the transverse velocity profiles are similar for two different turbulence models, the minimum Lipschitz-Hölder exponent <TEX>$ (\alpha _{\min })$</TEX> and entropy dimension <TEX>$ (\alpha _{1})$</TEX> are different. These results suggest that the multifractal exponents capture the difference in turbulence structures of hierarchical turbulence intensities produced by different turbulence models.</P>

Hamiltonian formalism of topologically massive electrodynamics

Kim, Taegyu,Kouwn, Seyen,Oh, Phillial World Scientific Publishing Company 2019 Modern Physics Letters A Vol.34 No.10

<P>We consider the four-dimensional topologically massive electrodynamics in which a gauge field interacts with rank two antisymmetric tensor field through a topological interaction. The photon becomes massive by eating the rank two tensor field, which is dual to the Higgs mechanism. We explicitly demonstrate the nature of the mechanism by performing a canonical analysis of the theory and discuss various aspects of it.</P>

Strange quark mass effect on the structure of hybrid stars

Xu, Jian-Feng,Luo, Yan-An,Li, Lei,Peng, Guang-Xiong World Scientific Publishing Company 2018 International Journal of Modern Physics E Vol.27 No.1

<P>We study the strange quark mass effect on the phase diagram of strong interaction and the structure of compact stars with a thermodynamically enhanced perturbative QCD model by matching quark matter onto nuclear matter using the Gibbs conditions. It is found that the mass effect of strange quark matter can obviously stiffen the equation of state of mixed phases and result in more massive hybrid stars (HSs), while that usually lowers the maximum mass of pure quark stars. Given reasonable model parameters, the maximum mass of HSs can reach two times the solar mass and the stars always have mixed-phase core in a considerably wide range of model parameters.</P>

Polynomial invariants for virtual marked graphs and virtual surface-link theory I

World Scientific Publishing Company 2017 Journal of knot theory and its ramifications Vol.26 No.12

<P>In this paper, we introduce a notion of virtual marked graphs and their equivalence and then define polynomial invariants for virtual marked graphs using invariants for virtual links. We also formulate a way how to define the ideal coset invariants for virtual surface-links using the polynomial invariants for virtual marked graphs. Examining this theory with the Kauffman bracket polynomial, we establish a natural extension of the Kauffman bracket polynomial to virtual marked graphs and found the ideal coset invariant for virtual surface-links using the extended Kauffman bracket polynomial.</P>

Lattice stick number of spatial graphs

Yoo, Hyungkee,Lee, Chaeryn,Oh, Seungsang World Scientific Publishing Company 2018 Journal of knot theory and its ramifications Vol.27 No.8

<P>The lattice stick number of knots is defined to be the minimal number of straight sticks in the cubic lattice required to construct a lattice stick presentation of the knot. We similarly define the lattice stick number <TEX>$ s_{L}(G)$</TEX> of spatial graphs <TEX>$ G$</TEX> with vertices of degree at most six (necessary for embedding into the cubic lattice), and present an upper bound in terms of the crossing number <TEX>$ c(G)$</TEX>$ s_{L}\left(G\right) \leq 3c\left(G\right) + 6e - 4v - 2s + 3b + k,$ where <TEX>$ G$</TEX> has <TEX>$ e$</TEX> edges, <TEX>$ v$</TEX> vertices, <TEX>$ s$</TEX> cut-components, <TEX>$ b$</TEX> bouquet cut-components, and <TEX>$ k$</TEX> knot components.</P>

Polynomial splittings of correction terms and doubly slice knots

Kim, Se-Goo,Kim, Taehee World Scientific Publishing Company 2018 Journal of knot theory and its ramifications Vol.27 No.1

<P>We show that if the connected sum of two knots with coprime Alexander polynomials is doubly slice, then the Ozsváth-Szabó correction terms, as smooth double sliceness obstructions, vanish for both knots. Recently, Meier gave smoothly slice knots that are topologically doubly slice, but not smoothly doubly slice. As an application, we give a new example of such a knot that is distinct from Meier’s knots modulo doubly slice knots.</P>

Circuit presentation and lattice stick number with exactly four <tex> $ z$</tex> -sticks

Kim, Hyoungjun,No, Sungjong World Scientific Publishing Company 2018 Journal of knot theory and its ramifications Vol.27 No.8

<P>The lattice stick number <TEX>$ s_{L}(L)$</TEX> of a link <TEX>$ L$</TEX> is defined to be the minimal number of straight line segments required to construct a stick presentation of <TEX>$ L$</TEX> in the cubic lattice. Hong, No and Oh [Upper bound on lattice stick number of knots, <I>Math. Proc. Cambridge Philos. Soc.</I><B>155</B> (2013) 173-179] found a general upper bound <TEX>$ s_{L}(K) \leq 3c(K) + 2$</TEX>. A rational link can be represented by a lattice presentation with exactly 4 <TEX>$ z$</TEX>-sticks.</P><P>An <TEX>$ n$</TEX>-circuit is the disjoint union of <TEX>$ n$</TEX> arcs in the lattice plane <TEX>$ \mathbb{Z}^{2}$</TEX>. An <TEX>$ n$</TEX>-circuit presentation is an embedding obtained from the <TEX>$ n$</TEX>-circuit by connecting each <TEX>$ n$</TEX> pair of vertices with one line segment above the circuit. By using a two-circuit presentation, we can easily find the lattice presentation with exactly four <TEX>$ z$</TEX>-sticks.</P><P>In this paper, we show that an upper bound for the lattice stick number of rational <TEX>$ \frac{p}{q}$</TEX>-links realized with exactly four <TEX>$ z$</TEX>-sticks is <TEX>$ 2p + 6$</TEX>. Furthermore, it is <TEX>$ 2p + 5$</TEX> if <TEX>$ L$</TEX> is a two-component link.</P>

NEW FINDINGS ON RIVER NETWORK ORGANIZATION: LAW OF EIGENAREA AND RELATIONSHIPS AMONG HORTONIAN SCALING RATIOS

YANG, SOOHYUN,PAIK, KYUNGROCK WORLD SCIENTIFIC PUBLISHING COMPANY 2017 FRACTALS -LONDON- Vol.25 No.3

<P>Horton’s laws have long served as fundamental principles for fractal organization of a drainage basin. Scaling ratios of stream number, length, area, and side tributary have been proposed but the definitions of these basic variables are inconsistent. The concept of eigenarea can be utilized to resolve this issue. Here, we investigated the relationships among Hortonian scaling ratios using the concept of eigenarea. We found that the eigenarea ratio, likewise other scaling ratios, is invariant within a stream network, the law of eigenarea. We analytically revealed that the eigenarea ratio is equivalent to the stream length ratio. Our examination implies that Horton’s original two ratios of stream number and length can represent most Hortonian scaling ratios except Tokunaga ratio.</P>