OSCILLATORY BEHAVIOR AND COMPARISON FOR HIGHER ORDER NONLINEAR DYNAMIC EQUATIONS ON TIME SCALES

Sun, Taixiang,Yu, Weiyong,Xi, Hongjian The Korean Society for Computational and Applied M 2012 Journal of applied mathematics & informatics Vol.30 No.1

In this paper, we study asymptotic behaviour of solutions of the following higher order nonlinear dynamic equations $$S_n^{\Delta}(t,x)+{\delta}p(t)f(x(g(t)))=0$$ and $$S_n^{\Delta}(t,x)+{\delta}p(t)f(x(h(t)))=0$$ on an arbitrary time scale $\mathbb{T}$ with sup $\mathbb{T}={\infty}$, where n is a positive integer, ${\delta}=1$ or -1 and $$S_k(t,x)=\{\array x(t),\;if\;k=0,\\a_k(t)S_{{\kappa}-1}^{\Delta}(t),\;if\;1{\leq}k{\leq}n-1,\\a_n(t)[S_{{\kappa}-1}^{\Delta}(t)]^{\alpha},\;if\;k=n,$$ with ${\alpha}$ being a quotient of two odd positive integers and every $a_k$ ($1{\leq}k{\leq}n$) being positive rd-continuous function. We obtain some sufficient conditions for the equivalence of the oscillation of the above equations.

A Novel Approach to Controlling CaCO₃ Crystalline Assembly by Changing the Concentration of Poly(aspartic acid)

Zhou, Hongjian,Gao, Yanmin,Hwang, Sun-Gu,Lee, Dong-Yun,Park, Jung-Youn,Lee, Jae-Beom Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.11

$CaCO_3$ crystalline structures having novel assemblies were in situ fabricated as analogs of naturally occurring proteins and polysaccharides for biomineralization. The calcite crystal was mineralized in a poly(vinyl alcohol)-$Ca^{2+}$ complex film immersed in a $Na_2CO_3$ solution containing poly(aspartic acid). The morphology and size of the $CaCO_3$ crystals were tuned by varying the concentration of poly(aspartic acid). The mechanisms of their nucleation orientation and formation were investigated experimentally and through molecular dynamics (MD) simulations in order to obtain a better understanding of the interactions between the polymers and the crystal at the molecular level. Both the MD results and experimental results indicate that the interaction between PVA and calcite mainly depends on the concentration of the polymer. The novel approach proposed herein for the fabrication of inorganic crystalline assembly structures can be used to fabricate precise crystalline structures.

OSCILLATORY BEHAVIOR AND COMPARISON FOR HIGHER ORDER NONLINEAR DYNAMIC EQUATIONS ON TIME SCALES

Taixiang Sun,Weiyong Yu,Hongjian Xi 한국전산응용수학회 2012 Journal of applied mathematics & informatics Vol.30 No.1

In this paper, we study asymptotic behaviour of solutions of the following higher order nonlinear dynamic equations [수식] and [수식] on an arbitrary time scale T with sup T = ∞ , where n is a positive integer, where n is a positive integer, [수식] and [수식] with a being quotient of two odd positive integers and every ak (1≤k≤n) being positive rd-continuous function. We obtain some sufficient conditions for the equivalence of the oscillation of the above equations.

Cytotoxicity and Gene Expression in Sarcoma 180 Cells in Response to Spiky Magnetoplasmonic Supraparticles

Zhou, Hongjian,Choi, Sun Il,Zou, Fengming,Oh, Sangjin,Kim, Ji Eun,Hwang, Dae Youn,Lee, Jaebeom American Chemical Society 2014 ACS APPLIED MATERIALS & INTERFACES Vol.6 No.22

<P>Multifunctional nanoparticles (NPs) have been designed for a variety of cell imaging and therapeutic applications, and the study of their cellular interactions is crucial to the development of more efficient biomedical applications. Among current nanomaterials, concave core–shell NPs with complex angled geometries are attractive owing to their unique shape-dependent optical and physical properties as well as different tendency for cell interaction. In this study, we investigated the morphology effect of spiky gold-coated iron oxide supraparticles (Fe<SUB>3</SUB>O<SUB>4</SUB>@Au SPs) on cytotoxicity and global gene expression in sarcoma 180 cells. Cells treated for 7 days with spiky supraparticles (SPs) at concentrations up to 50 μg/mL showed >90% viability, indicating that these NPs were nontoxic. To shed light on the differences in cytotoxicity, we monitored the expression of 33 315 genes using microarray analysis of SP-treated cells. The 171 up-regulated genes and 181 down-regulated genes in spiky SP-treated cells included <I>Il1b</I>, <I>Spp1</I>, <I>Il18</I>, <I>Rbp4</I>, and <I>Il11ra1</I>, where these genes are mainly involved in cell proliferation, differentiation, and apoptosis. These results suggested that the spiky Fe<SUB>3</SUB>O<SUB>4</SUB>@Au SPs can induce noncytotoxicity and gene expression in tumor cells, which may be a promising cornerstone on which to base related research such as cyto-/genotoxicology of nanomaterials or the design of nanoscale drug carriers.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2014/aamick.2014.6.issue-22/am504632g/production/images/medium/am-2014-04632g_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am504632g'>ACS Electronic Supporting Info</A></P>

Robust Power Control for Cognitive Radio in Spectrum Underlay Networks

( Nan Zhao ),( Hongjian Sun ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.7

Power control is a key technique in spectrum underlay cognitive network to guarantee the interference temperature limit of the primary users (PUs) and the quality of service of the secondary users (SUs). In this paper, a robust power control scheme via link gain pricing with H∞ estimator is proposed. The scheme guarantees the interference temperature of the PUs through operating in the network-centric manner, and keeps the fairness between the SUs through link gain pricing. Furthermore, the H∞ filter is also used in the proposed scheme to estimate the channel variation, and thus the power control scheme is robust to the severe channel fading. Plenty of simulations are taken, and prove its superior robust performance against the channel fading, and its effectiveness in guaranteeing the interference temperature limit of the PUs.

A Hybrid Multiuser Detection Algorithm for Outer Space DS-UWB Ad-hoc Network with Strong Narrowband Interference

( Zhendong Yin ),( Yunsheng Kuang ),( Hongjian Sun ),( Zhilu Wu ),( Wenyan Tang ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.5

Formation flying is an important technology that enables high cost-effective organization of outer space aircrafts. The ad-hoc wireless network based on direct-sequence ultra-wideband (DS-UWB) techniques is seen as an effective means of establishing wireless communication links between aircrafts. In this paper, based on the theory of matched filter and error bits correction, a hybrid detection algorithm is proposed for realizing multiuser detection (MUD) when the DS-UWB technique is used in the ad-hoc wireless network. The matched filter is used to generate a candidate code set which may contain several error bits. The error bits are then recognized and corrected by an novel error-bit corrector, which consists of two steps: code mapping and clustering. In the former step, based on the modified optimum MUD decision function, a novel mapping function is presented that maps the output candidate codes into a feature space for differentiating the right and wrong codes. In the latter step, the codes are clustered into the right and wrong sets by using the K-means clustering approach. Additionally, in order to prevent some right codes being wrongly classified, a sign judgment method is proposed that reduces the bit error rate (BER) of the system. Compared with the traditional detection approaches, e.g., matched filter, minimum mean square error (MMSE) and decorrelation receiver (DEC), the proposed algorithm can considerably improve the BER performance of the system because of its high probability of recognizing wrong codes. Simulation results show that the proposed algorithm can almost achieve the BER performance of the optimum MUD (OMD). Furthermore, compared with OMD, the proposed algorithm has lower computational complexity, and its BER performance is less sensitive to the number of users.

The dynamic transcriptome of waxy maize (Zea mays L. sinensis Kulesh) during seed development

Wei Gu,Diansi Yu,Yuan Guan,Hui Wang,Tao Qin,Pingdong Sun,Yingxiong Hu,Jihui Wei,Hongjian Zheng 한국유전학회 2020 Genes & Genomics Vol.42 No.9

Background Waxy maize (Zea mays L. sinensis Kulesh) is a mutant of maize (Zea mays L.) with a mutation at Waxy1 (Wx1) gene locus. The seed of waxy maize has higher viscosity compared to regular maize. By now, we know little about the expression patterns of genes that involved in the seed development of waxy maize. Objective By analyzing the transcriptome data during waxy maize seed development, we attempt to dig out the genes that may infuence the seed development of waxy maize. Methods The seeds of waxy maize inbred line SWL01 from six phases after pollination were used to do RNA-seq. Bioinformatics methods were used to analyze the expression patterns of the expressed genes, to identify the genes involved in waxy maize seed development. Results A total of 24,546 genes including 1611 transcription factors (TFs) were detected during waxy maize seed development. Coexpression analysis of expressed genes revealed the dynamic processes of waxy maize seed development. Particularly, 2457 genes including 177 TFs were specially expressed in waxy maize seed, some of which mainly involved in the process of seed dormancy and maturation. In addition, 2681, 5686, 4491, 4386, 3669 and 4624 genes were identifed to be diferential expressed genes (DEGs) at six phases compared to regular maize B73, and 113 DEGs among them may be key genes that lead the diference of seed development between waxy and regular maizes in milk stage. Conclusion In summary, we elucidated the expression patterns of expressed genes during waxy maize seed development globally. A series of genes that associated with seed development were identifed in our research, which may provide an important resource for functional study of waxy maize seed development to help molecular assisted breeding.