All-Benzocyclobutene Functionalized Polycarbosilane and Derived Copolymers with Low Dielectric Constant and High Thermal Stability

Nan Zhong,Xian Li,Huan Hu,Yawen Huang,Xu Ye,Junxiao Yang 한국고분자학회 2019 Macromolecular Research Vol.27 No.12

All-benzocyclobutene functionalized polycarbosilanes and the derived copolymers were successfully synthesized by ring-opening polymerization (ROP) of 1,1-dibenzocyclobutene-1-silacyclobutane (DBCBSCB) and 1,1-diphenylsiletane (DPSCB) using Karstedt’s catalyst. Adjusting the copolymerization ratio of DBCBSCB and DPSCB could afford to control the ultimate properties of the cured resins. The linear polycarbosilanes containing dibenzocyclobutene were directly cross-linked upon high temperature. With increasing the copolymerization ratio of DBCBSCB and DPSCB, the 5% weight loss temperature (T5%) of cured resins is increased from 450 °C to 506 °C under a nitrogen atmosphere, while the dielectric constant (k) is decreased from 2.60 to 2.42 at 10 MHz. The excellent thermostability and low-dielectric performance make such thermosets have potential application in the microelectronic industry.

Meromorphic Function that Shares One Small Function with its Differential Polynomial

Li, Nan,Yang, Lian-Zhong Department of Mathematics 2010 Kyungpook mathematical journal Vol.50 No.3

In this paper, we investigate the uniqueness problems of meromorphic functions that share a small function with its differential polynomials, and give a result which is related to a conjecture of R. Br$\"{u}$ck and improve the results of I. Lahiri and Q. C. Zhang.

Hydrophobic modification of silica/exfoliated graphite nanoplatelets aerogel and its application as supporting material for form-stable phase change materials

Ni Tan,Yang Feng,Ping Hu,QiLin Ding,Chuan-Huang Lin,Yu-Hao Ning,Hao-Nan Zhou,Linping Yu,Zhong Cao,Ju-Lan Zeng 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.99 No.-

Hydrophobic modified silica/exfoliated graphite nanoplatelets aerogel (M-SiO2/xGnP) were successfullyprepared via surface modification of silica/xGnP alcogel and followed by ambient pressure drying. Afterwards, form-stable PCMs in which capric–palmitic acids eutectic (CA–PA) was confined in theprepared aerogels were obtained by vacuum infiltration. Characterization of the prepared form-stablePCMs revealed that both the hydrophobic modification and the doping of xGnP could effectively improvethe loading of CA–PA in the aerogel. The unmodified silica aerogel could not adsorb CA–PA, while theloading of CA–PA in the surface modified pure silica aerogel supported form-stable PCM and theunmodified silica/xGnP aerogel supported form-stable PCM were 24.2 wt% and 44.4 wt%, respectively. Besides, the hydrophobic modification and the doping of xGnP showed significant synergistic effect. Theloading of CA–PA in the M-SiO2/xGnP supported form-stable PCM (FPCM/xGnP-20-48) could attain78.9 wt% when the M-SiO2/xGnP was obtained by modifying the alcogel with 20 vol% trimethylchlorosilane for 48 h. The FPCM/xGnP-20-48 not only had high latent heat and good thermal reliability,but also exhibited significantly improved thermal conductivity and alleviated supercooling due to theeffective thermal conductive network formed by xGnP and the promoted heterogeneous nucleation ofCA–PA at interfaces with aerogel.

Structure-based design, structure–activity relationship analysis, and antitumor activity of diaryl ether derivatives

Shao-Mei Yang,Fu-Nan Li,Zhi-Ning Huang,Zhong-Shi Zhou,Jin Hou,Man-Yi Zheng,Li-Juan Wang,Yu Jiang,Xin-Yi Zhou,Qiu-Yue Chen,Shan-Hua Li 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.10

To identify novel therapeutic agents to treatcancer, we synthesized a series of diaryl ether derivatives. Structure–activity relationship studies revealed that thepresence of a chlorine or hydroxyl at the para-position onthe phenyl ring (5h or 5k) significantly enhanced antitumoractivity. Compound 5h had stronger growth inhibitory activityin HepG2, A549, and HT-29 cells than compound 5k,with IC50 values of 2.57, 5.48, and 30.04 lM, respectively. Compound 5h also inhibited the growth of other cells lines,including Hep3B, PLC/PRF5, SMMC-7721, HeLa, andA375, with IC50 values of 2.76, 4.26, 29.66, 18.86, and10.21 lM, respectively. The antitumor activity of compound5h was confirmed by a colony forming assay. Further,our results indicated that the antitumor activity ofcompound 5h may be mediated by enhancing expression ofp21 and cl-caspase3, and leading to apoptosis of cancercells.

Multiple down-regulated cytochrome P450 monooxygenase genes contributed to synergistic interaction between chlorpyrifos and imidacloprid against Nilaparvata lugens

Lu Xue,Guanghua Luo,Yang Sun,Shuijin Huang,De-Jin Xu,Guang-Chun Xu,Zhao-Jun Han,Zhong-Yan Gu,Ya-Nan Zhang 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.1

Insecticide mixtures are an effective strategy in pest resistance management. The synergistic chlorpyrifos and imidacloprid mixture could significantly increase toxicity against rice pest, Nilaparvata lugens, despite their high levels of resistance. However, synergism mechanisms to explain this phenomenon remain unknown. Chlorpyrifos and imidacloprid at a 1:0.5 ratio showed significant synergism on N. lugens with a combination index value of 0.18 after topical exposure. We constructed a genetic database of the genes expressed in individual and synergistic chlorpyrifos and imidacloprid treatments of N. lugens using Illumina Hiseq™ X Ten, and 17 co-downregulated genes putatively involved in synergism were detected by comparative transcriptome analyses. Expression patterns of the 17 candidate synergistic genes matched with transcriptome sequencing data by quantitative real-time PCR analyses. Feeding of dsRNAs further reduced the expression levels of 10 of these candidate synergistic genes (from 1.68 to 4.13-fold). Nymphs fed with only dsRNAs of CYP4DE1, CYP6AY1v2, CYP353D1, and CYP439A1 experienced more high mortality rates (81.45–90.34%) to improve synergism between chlorpyrifos and imidacloprid. Multiple reductive expressed P450 genes were potentially associated with synergism of a mixture of chlorpyrifos and imidacloprid, as confirmed by comparative transcriptome analyses and RNAi assays. Our findings suggested that synergistic interactions between chlorpyrifos and imidacloprid might be controlled by P450s.

New method for rapidly estimating population densities of the concealed wood‐borer Monochamus alternatus (Coleoptera: Cerambycidae) in the field

Xiao‐Yi Wang,Zhong-qi Yang,Chun-Nan SITU,Jian WANG,Fu-Yong FU 한국곤충학회 2016 Entomological Research Vol.46 No.2

To rapidly estimate pine sawyer, Monochamus alternatus Hope, population densities in forests, the vertical distributions of M. alternatus oviposition sites and larvae on infested Masson pines (Pinus massoniana Lamb.) were studied. Results showed that the number of oviposition sites on sections of trunks between 0 and 2 m above ground was significantly greater than on sections of trunk above 2 m, and the vertical distribution had a significant logarithmic relationship with trunk height. The larval number of M. alternatus on dead infested trees had a significant difference among heights of trunks. Sections on trunks at 2–4 m usually contained the largest number of M. alternatus larvae, while the number of larvae on trunks above 10 m declined significantly, as well as in the 1 m section of trunk at the base. The vertical distribution of M. alternatus larvae on dead infested pines showed a distinct parabolic relationship with trunk height. The number of oviposition sites of M. alternatus on infested Masson pine trunks revealed a significant exponential relationship with the diameter at breast height (DBH) of trees. A significant positive linear relationship also was observed between M. alternatus larval number and DBH on the host pine trees, as well as between the numbers of larvae and oviposition sites on an individual tree. The total number of larvae in an infested tree could be calculated easily using an established equation, through counting the number of oviposition sites at 3–4 m of trunk aboveground. This study developed a practical method for rapid estimation of M. alternatus populations.

CLV1 Interacts with UFO in Modulation of Gynoecium Development in Arabidopsis thaliana

Zhi-Peng Cheng,Zhong-Nan Yang,Sen Zhang 한국식물학회 2013 Journal of Plant Biology Vol.56 No.1

The gynoecium is the female reproductive structurein flowering plants. It has been known that the CLAVATA1(CLV1) gene regulates the floral meristem maintenance andfloral organ number in Arabidopsis thaliana. However,whether CLV1 plays roles in gynoecium development remainsuncharacterized. In this study, we showed that CLV1genetically interacts with Unusual Floral Organs (UFO) toregulate the development of Arabidopsis gynoecium. Throughforward genetic screen, we identified a clv1 allele, clv1-9,showing abnormal gynoecium development. Some epidermalcells on the growing inner surfaces of the clv1-9 gynoeciumfailed to fuse after contacting with each other, suggesting thatCLV1 is essential for proper postgenital fusion. Furthermore,the ufo clv1-9 double mutant exhibited an expanded uppergynoecium, narrowed lower part of the ovary, alteredvascular patterning and abaxial outward proliferation of thetransmitting tract tissues. The transcription level of the ETTgene, which is required for gynoecium structure and patternformation, was down-regulated in the ufo clv1-9 doublemutant genoecia. Taken together, our results indicate thatCLV1 functions together with UFO to regulate gynoeciumdevelopment likely through modulating the expression ofETT.

Orthogonal 방법을 통한 Poly(AM-DMDAAC)/MMT 고흡수성나노복합체 제조 연구

Jun Dong Yuan,Ming Zhou,Shuang Qiao Yang,Yong Guo Zhou,Nan Qin,Song Tao He,Dong Lai,Zhong Qiang Xie 한국고분자학회 2014 폴리머 Vol.38 No.1

A novel poly(AM-DMDAAC)/MMT superabsorbent nanocomposites are prepared by radical polymerizationusing ammonium persulfate (APS) and anhydrous sodium sulfite as a free radical initiator and N,N-methylene bisacrylamide(MBA) as a crosslinker. In this paper, an optimization study on the synthesis of superabsorbent nanocompositesis carried out. Orthogonal array experiment indicates that the optimized conditions is acrylamide (AM) content 23 wt%,diallyl dimethyl ammonium chloride (DMDAAAC) content 6 wt%, montmorillonite (MMT) content 4 wt%, initiatorcontent 0.2 wt% and crosslinker content 0.02 wt%. Under the optimization syntheses conditions concluded, the maximumwater absorbency in distilled water is 659.53 g·g-1 and in 2 wt% sodium chloride solution is 116.25 g·g-1. Compared withthe range values of different factors (Rj), the order of significance factors in distilled water is C (MMT) > B (DMDAAC)> A (AM) > D (crosslinker) > E (initiator). MMT is intercalated during polymerization reaction and a nanocompositestructure is formed as shown by TEM analysis and XRD analysis.

ACOS5 is Required for Primexine Formation and Exine Pattern Formation During Microsporogenesis in Arabidopsis

Hui-hui Xie,Lin Chen,Fa-qing Xu,Wan-sheng Guo,Shui Wang,Zhong-Nan Yang,Sen Zhang 한국식물학회 2017 Journal of Plant Biology Vol.60 No.4

Pollen exine, mainly composed of sporopollenin,plays important roles during microspore development. It hasbeen reported that Acyl-CoA Synthetase5 (ACOS5) is requiredfor sporopollenin biosynthesis in Arabidopsis. Here we showthat ACOS5 is essential for primexine formation duringArabidopsis microspore development. Through genetic screen,we identified a point mutation of ACOS5 allele, acos5-2,showing abnormal microspore development. Its microsporeswere degenerated and aborted after released from the tetrads. Transmission electron microscopy showed that primexineformation was reduced in acos5-2 mutant as compared tothat of the wild-type. Consequently, sporopollenin wasaggregated and randomly deposited on the microspores. Insitu hybridization indicated that the key regulators of tapetumdevelopment, DYT1 and TDF1, are required for the expressionof ACOS5 in tapetum. Furthermore, the GUS reporter showedthat the 593-bp promoter sequence was sufficient for theexpression of ACOS5 in the anther. Our data provide evidencethat ACOS5 is required for primexine formation andsporopollenin deposition during microspore development.

Combination of Tumor Volume and Epstein-Barr Virus DNA Improved Prognostic Stratification of Stage II Nasopharyngeal Carcinoma in the Intensity Modulated Radiotherapy Era: A Large-Scale Cohort Study

Qiu-Yan Chen,Shao-Yan Guo,Lin-Quan Tang,Tong-Yu Lu,Bo-Lin Chen,Qi-Yu Zhong,Meng-Sha Zou,Qing-Nan Tang,Wen-Hui Chen,Shan-Shan Guo,Li-Ting Liu,Yang Li,Ling Guo,Hao-Yuan Mo,Rui Sun,Dong-Hua Luo,Chong Zha 대한암학회 2018 Cancer Research and Treatment Vol.50 No.3

Purpose Little is known about combination of the circulating Epstein-Barr viral (EBV) DNA and tumor volume in prognosis of stage II nasopharyngeal carcinoma (NPC) patients in the intensity modulated radiotherapy (IMRT) era. We conducted this cohort study to evaluate the prognostic values of combining these two factors. Materials and Methods By Kaplan-Meier, we compare the differences of survival curves between 385 patients with different EBV DNA or tumor volume levels, or with the combination of two biomarkers mentioned above. Results Gross tumor volume of cervical lymph nodes (GTVnd, p < 0.001) and total tumor volume (GTVtotal, p < 0.001) were both closely related to pretreatment EBV DNA, while gross tumor volume of nasopharynx (GTVnx, p=0.047) was weakly related to EBV DNA. EBV DNA was significantly correlated with progress-free survival (PFS, p=0.005), locoregional-free survival (LRFS, p=0.039), and distant metastasis-free survival (DMFS, p=0.017), while GTVtotal, regardless of GTVnx and GTVnd, had a significant correlation with PFS and LRFS. The p-values of GTVtotal for PFS and LRFS were 0.008 and 0.001, respectively. According to GTVtotal and pretreatment EBV DNA level, patients were divided into a low-risk group (EBV DNA 0 copy/mL, GTVtotal < 30 cm3; EBV DNA 0 copy/mL, GTVtotal  30 cm3; or EBV DNA > 0 copy/mL, GTVtotal < 30 cm3) and a high-risk group (EBV DNA > 0 copy/mL, GTVtotal  30 cm3). When patients in the low-risk group were compared with those in the high-risk group, 3-year PFS (p=0.003), LRFS (p=0.010), and DMFS (p=0.031) rates were statistically significant. Conclusion Pretreatment plasma EBV DNA and tumor volume were both closely correlated with prognosis of stage II NPC patients in the IMRT era. Combination of EBV DNA and tumor volume can refine prognosis and indicate for clinical therapy.