Comparison of volatile organic compounds from uninfested and Monochamus alternatus Hope infested Pinus massoniana Lamb.

Xiao‐Juan Li,Guang-Ping DONG,Jian-Min FANG,Hong-Jian LIU,Wan-Lin GUO 한국곤충학회 2017 Entomological Research Vol.47 No.3

Monochamus alternatus is a destructive stem‐boring herbivore of Pinus massoniana, and the principal vector of pine wood nematode. To investigate the impacts of boring by M. alternatus larvae on the emission of volatile organic compounds (VOCs) from their host trees, the VOCs from uninfested and M. alternatus larvae infested P. massoniana trees were observed using a gas chromatograph–mass spectrometer. We detected 12, 9, 18 and 14 volatile organic compounds from infested xylem, infested phloem, uninfested xylem and uninfested phloem, respectively. In P. massoniana xylem, the boring of M. alternatus larvae induced cyclosativene, and inhibited 4‐carene, humulene, styrene, α‐phellandrene, β‐myrcene, β‐phellandrene and γ‐terpinene. The relative amounts of camphene, copacamphene, longicyclene, longifolene, tricyclene and α‐longipinene were significantly increased, and the relative amounts of α‐pinene and β‐pinene were significantly decreased by the boring behaviors of M. alternatus larvae. In P. massoniana phloem, the boring of M. alternatus larvae induced 2‐bornanone, copacamphene, longicyclene and α‐longipinene, and inhibited 2‐carene, 4‐carene, styrene, α‐phellandrene, β‐myrcene, β‐phellandrene, β‐pinene, γ‐terpinene and ο‐cymene. The relative amounts of camphene, caryophyllene and longifolene were significantly increased by the boring behaviors of M. alternatus larvae. The results indicate that the boring behaviors of M. alternatus larvae changed both the sorts and contents of the VOCs from P. massoniana trees.

Evolutionary dynamics of transposable elements during silkworm domestication

Min‑Jin Han,Hong‑En Xu,Xiao‑Min Xiong,Hua‑Hao Zhang 한국유전학회 2018 Genes & Genomics Vol.40 No.10

Although there are some documented examples on population dynamics of transposable elements (TEs) in model organisms, the evolutionary dynamics of TEs in domesticated species has not been systematically investigated. The objective of this study is to understand population dynamics of TEs during silkworm domestication. In this work, using transposondisplay we examined the polymorphism of seven TE families [they represent about 59% of silkworm (Bombyx mori) total TE content] in four domesticated silkworm populations and one wild silkworm population. Maximum likelihood (ML) was used to estimate selection pressure. Population differentiation and structure were performed by using AMOVA analysis and program DISTRUCT, respectively. The results of transposon-display showed that significant differentiation occurred between the domesticated silkworm and wild silkworm. These TEs have experienced expansions and fixation in the domesticated silkworm but not in wild silkworm. Furthermore, the ML results indicated that purifying selection of TEs in the domesticated silkworm were significantly weaker than that in the wild silkworm. Interestingly, an adaptation insertion induced by BmMITE-2 was found, and this insertion can reduce the polymorphism of the flanking regions of its neighboring COQ7 gene. Our results suggested that TEs expanded and were fixed in the domesticated silkworm might result from demographic effects and artificial selection during domestication. We concluded that the data presented in this study have general implication in animal and crop improvements as well as in domestication of new species.

Three-dimensional Network Structure of Conductive Composites by Hybrid Conductive Fillers of Silver/graphene

Xiao Min Zhang,Kun-yan Wang,Guo Zhao,Qi Long Li,Bin Wang 한국섬유공학회 2019 Fibers and polymers Vol.20 No.6

In order to explore new generations of interconnecting materials in electronic packaging industries, silvernanoparticles (Ag NPS) and graphene nanosheets (GNS) were introduced into matrix resin to prepare conductive composites. The electrical and mechanical of above electrically conductive adhesives (ECAs) were investigated and characterized. It wasfound that the ECAs can be solidified through a chemical sintering in the air at 150 oC for 30 min. The results indicated thatthe percolation threshold of resistivity reaches 3.5×10-4 Ω·cm for ECAs filled with 65 wt.% Ag NPS, 0.5 wt.% GNS and theshear strength reaches 10.8 MPa, suggesting excellent electric conductivity and bonding strength.

Identification of differentially expressed immunity‐related genes in Monochamus alternatus Hope (Coleoptera: Cerambycidae) larvae parasitized by Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae)

Xiao‐Juan Li,Guang-Ping DONG,Jian-Min FANG,Hong-Jian LIU,Wan-Lin GUO 한국곤충학회 2018 Entomological Research Vol.48 No.4

The pine sawyer Monochamus alternatus Hope (Coleoptera: Cerambycidae) is a serious pest of several Pinus species, and the ectoparasitoid larvae of Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) is an important natural enemy of this pest. The transcriptome of M. alternatus larvae was sequenced using the Illumina platform and immunity‐related genes were specifically analyzed. De novo assembly resulted in the identification of 24 241 unigenes, with a mean length of 1122 bp, in unparasitized M. alternatus larvae and 23 807 unigenes, with a mean length of 1140 bp, for parasitized larvae. Removal of redundant unigenes resulted in 26 095 all‐unigenes, of which 16 959 (64.99%) showed clear homology with some of the known genes in the National Center for Biotechnology Information nr database. Parasitization had notable effects on the transcriptome profile of M. alternatus larvae. In all, 2702 genes were differentially expressed in M. alternatus larvae after parasitization, with 1491 (55.18%) upregulated and 1211 (44.82%) downregulated. Moreover, expression levels of immunity‐related genes in M. alternatus larvae were markedly altered in response to parasitization by D. helophoroides. In conclusion, the transcriptome profiling data, especially the discovered of immunity‐related genes, help illustrate the molecular mechanisms of parasitism between D. helophoroides and M. alternatus and provide new insights into developing immunity regulation‐mediated control methods of M. alternatus.

Some Further Results on Weighted Sharing of Values for Meromorphic Functions Concerning a Result of Terglane

Li, Xiao-Min,Yi, Hong-Xun Department of Mathematics 2008 Kyungpook mathematical journal Vol.48 No.3

In this paper, we deal with the problem of meromorphic functions that have three weighted sharing values, and obtain some uniqueness theorems which improve those given by N. Terglane, Hong-Xun Yi & Xiao-Min Li, and others. Some examples are provided to show that the results in this paper are best possible.

Performance of fluidized bed electrode in a molten carbonate fuel cell anode

Jubing Zhang,Zhaoping Zhong,Jianmin Xiao,Zongming Fu,Jinxiao Zhao,Weiling Li,Min Yang 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.8

A fluidized bed electrode could lower concentration polarization and activation polarization because of its high mass and heat transfer coefficient. The polarization characteristics of the fluidized bed electrode are systematically investigated in a molten carbonate fuel cell anode with an O_2/CO_2/gold reference electrode. The results show that polarization performance of the anode is improved by selecting proper flow rates of H_2, O_2 and CO_2, choosing suitable nickel particle content together with appropriate O_2/CO_2 ratio, and increasing reaction temperature as well as the area of the current collector. Limiting current density of 115.56 mA·cm^(−2) is achieved under optimum performance as follows:a cylindrically curved nickel plate current collector, nickel particle content of 7.89%, the reaction temperature of 923 K,H_2 flow rate of 275 mL·min^(−1), O_2/CO_2 flow rate of 10/20 mL·min−1 and O_2/CO_2 ratio of 1 : 2.

Effect of the Oxygen Flux Ratio on the Structural and the Optical Properties of Silver-oxide Films Deposited by Using the Direct-current Reactive Magnetron Sputtering Method

Xiao-Yong Gao,Hong-Liang Feng,Zeng-Yuan Zhang,Jiao-Min Ma,Meng-Ke Zhao,Chao Chen,Jin-Hua Gu,Shi-E Yang,Yong-Sheng Chen,Jing-Xiao Lu 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.2

Using values of the oxygen flux ratio (OFR = [O2]/[Ar]) ranging from 0 to 0.5, authors deposited a series of silver-oxide (Ag_xO) films on glass substrates by direct-current reactive magnetron sputtering (DC sputtering) at a substrate temperature of 150 ℃. The effect of the OFR on the film’s structural and optical properties was systematically investigated by using X-ray diffractometry, scanning electron microscopy and spectrophotometry. The Ag_xO films deposited clearly show an evolution of the film’s phase structure from the biphased (Ag + Ag_2O) structure to the biphased (AgO + Ag_2O) structure and then to the single-phased (Ag_2O) structure as value of the OFR increases. Accordingly, the film’s surface morphology, related to the film’s crystalline structure, clearly changes from a loose and porous surface structure to a compact surface structure and then to a pyramid-like surface structure with increasing value of the OFR. The novel porous structure may be attributed to the interruption of the silver’s growth course by the AgO on the film’s surface. Notably, a single-phased Ag_2O film is deposited by DC-sputtering at OFR = 0.5 due to the dual effects of thermal decomposition of the AgO phase and a combination reaction of AgO and Ag to Ag_2O. The oscillations both in the film’s reflectivity and transmissivity spectra are strengthened with increasing OFR, indicating an evolution from the metallic behavior of the biphased (Ag + Ag_2O) film to the dielectric behavior of the biphased (Ag_2O + AgO) film and the single-phased Ag2O film. The fitted optical absorption edges of the Ag_2O and the Ag_xO films deposited at values of the OFR of 0.5 and 0.33 are approximately 2.43 eV and 2.34 eV, respectively. The absorption edges are closely related to the direct interband transitions.

FBXL20-mediated Vps34 ubiquitination as a p53 controlled checkpoint in regulating autophagy and receptor degradation

Xiao, Juan,Zhang, Tao,Xu, Daichao,Wang, Huibing,Cai, Yu,Jin, Taijie,Liu, Min,Jin, Mingzhi,Wu, Kejia,Yuan, Junying Cold Spring Harbor Laboratory Press 2015 Genes & development Vol.29 No.2

<P>Vps34, the catalytic subunit in the class III phosphatidylinositol 3 kinase complexes, mediates the production of PtdIns3P, a key intracellular lipid involved in regulating autophagy and receptor degradation. Xiao et al. show that DNA damage-activated mitotic arrest and CDK activation lead to the phosphorylation of Vps34. This provides a signal to promote Vps34 ubiquitination and proteasomal degradation mediated by FBXL20, leading to inhibition of autophagy and receptor endocytosis. Importantly, they also find that expression of FBXL20 is regulated by p53-dependent transcription.</P><P>Vacuolar protein-sorting 34 (Vps34), the catalytic subunit in the class III PtdIns3 (phosphatidylinositol 3) kinase complexes, mediates the production of PtdIns3P, a key intracellular lipid involved in regulating autophagy and receptor degradation. However, the signal transduction pathways by which extracellular signals regulate Vps34 complexes and the downstream cellular mechanisms are not well understood. Here we show that DNA damage-activated mitotic arrest and CDK activation lead to the phosphorylation of Vps34, which provides a signal to promote its ubiquitination and proteasomal degradation mediated by FBXL20 (an F-box protein) and the associated Skp1 (S-phase kinase-associated protein-1)–Cullin1 complex, leading to inhibition of autophagy and receptor endocytosis. Furthermore, we show that the expression of FBXL20 is regulated by p53-dependent transcription. Our study provides a molecular pathway by which DNA damage regulates Vps34 complexes and its downstream mechanisms, including autophagy and receptor endocytosis, through SCF (Skp1–Cul1–F-box)-mediated ubiquitination and degradation. Since the expression of FBXL20 is regulated by p53-dependent transcription, the control of Vps34 ubiquitination and proteasomal degradation by FBXL20 and the associated SCF complex expression provides a novel checkpoint for p53 to regulate autophagy and receptor degradation in DNA damage response.</P>

On a Result of Tohge

Xiao-Min Li,Hong-Xun Yi 경북대학교 자연과학대학 수학과 2004 Kyungpook mathematical journal Vol.44 No.3

This paper studies the problem of uniqueness of meromorphic functions which share the value zero with their first two derivatives, the result in this paper improves some theorems given by W. Saxer, W. K. Hayman, K. Tohge and other authors.

Novel miniature inverted-repeat transposable elements derived from novel CACTA transposons were discovered in the genome of the ant Camponotus floridanus

Xiao-Min Xiong,Shen-Hua Jiang,Guo-Yin Li 한국유전학회 2016 Genes & Genomics Vol.38 No.12

Fourteen novel miniature inverted-repeat transposable element (MITE) families are found in the Florida carpenter ant genome, Camponotus floridanus. They constitute approximately 0.63 % of the entire genome. Analysis of their insertion time showed that most members of these MITEs were inserted into their host genome in less than 8 million years ago. In addition, the association between MITEs and the noncoding regions of genes in C. floridanus is random. Interestingly, an autonomous partner (named CfTEC) responsible for the amplification of these MITEs was also found in C. floridanus. Meanwhile, we present evidence, based on searches of publicly available databases, that this autonomous element was widespread in animals. Moreover, structure and phylogenetic analyses supported that TECs might represent a novel cade of transposons intermediate between the classic CACTA transposon and TRCs. Finally, their transposition mechanism and impact on host genome evolution were also discussed.