멜라민 첨가 순서에 따른 UMF 접착제의 경화거동과 접착력의 영향

( Guang-zhu Xu1 ),엄영근 ( Young Geun Eom ),이영규 ( Young Kyu Lee ),임동혁 ( Dong Hyuk Lim ),이병호 ( Byoung Ho Lee ),김현중 ( Hyun Joong Kim ) 한국 접착 및 계면학회 2009 접착 및 계면 Vol.10 No.2

Effects of diff erent NO 3 − :NH 4 + ratios on the photosynthesis and ultrastructure of lettuce seedlings

Xu Zhu,Rui Yang,Yingyan Han,Jinghong Hao,Chaojie Liu,Shuangxi Fan 한국원예학회 2020 Horticulture, Environment, and Biotechnology Vol.61 No.3

Nitrate nitrogen (NO 3− ) and ammonium N (NH 4+ ) are the two main forms of nitrogen (N). The eff ects of the NO 3− :NH 4+ ratio(0:100, 25:75, 50:50, 75:25, and 100:0) in the nutrient solution on growth, pigment content, photosynthetic parameters, chlorophyll(Chl) precursor content, and chloroplast mitochondrial ultrastructure of lettuce leaves were evaluated to determine theappropriate N ratio for the growth of lettuce. The results showed that a ratio of nitrate to ammonium of 75:25 compared withthe single N form resulted in signifi cantly higher fresh weights in the shoots and the lower parts of the lettuce. The growthrate, as indicated by the CO 2 response curve, was increased because of the carboxylation effi ciency and dark respiration rate(Rday) of the lettuce seedlings, and the diff erence between the light compensation point and CO 2 compensation point wasreduced under single nitrate N treatment. The contents of δ-aminolevulinic acid (ALA), porphobilinogen, uroporphyrinogenIII, protoporphyrin IX, and Mg-protoporphyrin IX in seedlings at 75:25 nitrate:ammonium were higher than those inseedlings under the other treatments. The contents of Chl a and b were also the highest when the ratio of nitrate ammoniumwas 75:25. The chloroplast structure of lettuce leaves was intact, the cell membrane was completely closed to the cell wall,and the organelles were closely arranged on the cell membrane. The chloroplast was spindle-shaped and full of vesicles. The whole mitochondria were rich, the base particles were rich, the base granules were clear and rich, and the mitochondriaexhibited the overall best state with a complete structure, rich sputum, and dense inclusions. The above results show that thenutrient solution with a ratio of nitrate to ammonium of 75:25 was more conducive to Chl synthesis and the promotion ofphotosynthesis and root growth in lettuce seedlings than the other treatments. The single nitrate N nutrient solution reducedChl synthesis and photosynthesis in lettuce seedlings, while the single ammonium N nutrient solution aff ected the growthof lettuce seedlings, resulting in lower growth of lettuce shoots and roots. Therefore, the nutrient solution ratio of nitrate toammonium of 75:25 is the most suitable for the lettuce seedling growth.

Long-circulating siRNA nanoparticles for validating Prohibitin1-targeted non-small cell lung cancer treatment

Zhu, Xi,Xu, Yingjie,Solis, Luisa M.,Tao, Wei,Wang, Liangzhe,Behrens, Carmen,Xu, Xiaoyang,Zhao, Lili,Liu, Danny,Wu, Jun,Zhang, Ning,Wistuba, Ignacio I.,Farokhzad, Omid C.,Zetter, Bruce R.,Shi, Jinjun National Academy of Sciences 2015 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.112 No.25

<P><B>Significance</B></P><P>This study developed a new generation lipid–polymer hybrid nanoparticle platform for effective systemic delivery of small interfering RNA (siRNA) to tumors, which represents a challenging hurdle for the widespread application of RNA interference (RNAi) in cancer research and therapy. With promising in vivo features such as long blood circulation, high tumor accumulation, and effective gene silencing, the hybrid siRNA nanoparticles were successfully used to reveal and validate a putative therapeutic target, Prohibitin1 (PHB1), in non-small cell lung cancer treatment. In vivo antitumor efficacy results and human tissue microarray analysis further suggested the feasibility of utilizing PHB1 siRNA nanoparticles as a novel therapeutic agent. This hybrid RNAi nanoparticle platform may serve as a valuable tool for validating potential cancer targets and developing new cancer therapies.</P><P>RNA interference (RNAi) represents a promising strategy for identification and validation of putative therapeutic targets and for treatment of a myriad of important human diseases including cancer. However, the effective systemic in vivo delivery of small interfering RNA (siRNA) to tumors remains a formidable challenge. Using a robust self-assembly strategy, we develop a unique nanoparticle (NP) platform composed of a solid polymer/cationic lipid hybrid core and a lipid-poly(ethylene glycol) (lipid-PEG) shell for systemic siRNA delivery. The new generation lipid–polymer hybrid NPs are small and uniform, and can efficiently encapsulate siRNA and control its sustained release. They exhibit long blood circulation (<I>t</I><SUB>1/2</SUB> ∼8 h), high tumor accumulation, effective gene silencing, and negligible in vivo side effects. With this RNAi NP, we delineate and validate the therapeutic role of Prohibitin1 (PHB1), a target protein that has not been systemically evaluated in vivo due to the lack of specific and effective inhibitors, in treating non-small cell lung cancer (NSCLC) as evidenced by the drastic inhibition of tumor growth upon PHB1 silencing. Human tissue microarray analysis also reveals that high PHB1 tumor expression is associated with poorer overall survival in patients with NSCLC, further suggesting PHB1 as a therapeutic target. We expect this long-circulating RNAi NP platform to be of high interest for validating potential cancer targets in vivo and for the development of new cancer therapies.</P>

Association Between the Ku70-1310C/G Promoter Polymorphism and Cancer Risk: a Meta-analysis

Xu, Lu,Ju, Xiao-Bing,Li, Pu,Wang, Jue,Shi, Zhu-Mei,Zheng, Ming-Jie,Xue, Dan-Dan,Xu, Yan-Jie,Yin, Yong-Mei,Wang, Shui,You, Yong-Ping Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2

Ku70 plays an important role in DNA double-strand break repair. Studies revealing conflicting results on the role of the Ku70-1310C/G promoter polymorphism on cancer risk led us to perform a meta-analysis to investigate this relationship. Ten case-control studies with 2566 cases and 3058 controls were identified. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of associations. The overall results suggested no association between the Ku70-1310C/G promoter polymorphism and total cancer risk. However, on stratified analysis, significantly increased risks were observed among the Asian population (GG vs. CC: OR=1.50, 95%CI=1.10-2.06; GG vs. CC/CG: OR=1.47, 95%CI=1.07-2.01) and population-based case-control studies (GG vs. CC: OR=1.57, 95%CI=1.12-2.22; CG vs. CC: OR=1.35, 95%CI=1.11-1.64; CG/GG vs. CC: OR=1.37, 95%CI=1.14-1.65). Additionally, variant genotypes were associated with a significantly increased breast cancer risk (GG vs. CC: OR=1.80, 95%CI=1.26-2.56; GG vs. CC/CG: OR=1.40, 95%CI=1.01-1.95).

Inter regional diffusion of policy innovation in China A comparative case study

Xu-Feng Zhu 서울대학교행정대학원 2017 Asian Journal of Political Science Vol.25 No.3

Classic theoretical research on the diffusion of policy innovation is usually based on decentralized democratic regimes. However, in authoritarian centralized countries such as China, questions such as, ‘What are the driving forces and the structural dynamics behind local government policy innovation and inter-regional diffusion?’ and ‘How do the governmental structural factors lead to the different patterns of diffusion of policy innovation across local governments?’ are interesting research topics. The theoretical framework proposed in this study highlights the roles of the contingent vertical and horizontal governmental relations in innovation diffusion. I extract two key properties: vertical mandatory intervention from the central government and horizontal political competition among peer governments. This research uses four models to develop a new typology of the interregional diffusion of policy innovation in China: (1) the enlightenment model, (2) the championship model, (3) the designation model, and (4) the recognition model. A comparative case study is conducted in this research, with four policy cases showing that China has developed diversified mechanisms to encourage local governments to perform policy innovation and inter-regional diffusion.

Interaction between Metalloporphyrins and Diazine Tautomers

Xu, Huiying,Wang, Wei,Zhu, Jianqing,Xu, Xiaolu,Zhang, Deyong Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.12

The interaction between metalloporphyrins and diazine tautomers was investigated using quantum chemistry method. The results showed that the metal atom in the metalloporphyrin was not coplanar with porphin ring, and zinc porphyrin has the most extent of its non-coplanar nature. The most stable complex in nine complexes was iron porphyrin. NBO analysis indicated that the interaction between the lone pair of electrons on the nitrogen atom and the unoccupied lone pair orbital of metal contributes significantly to the stability of the complexes. Through the conceptual DFT parameter and Fukui dual descriptor, the thermodynamic stability and reactivity of complexes were analyzed. The density difference function (DDF) analyzes were performed to explore the rearrangement of electronic density after the coordination interaction. NICS calculation indicated that metalloporphyrin aromaticity was reduced after the coordination interaction, and aromaticity of diazine tautomer was increased along direction vector of the coordination interaction force.

Linkage Disequilibrium Estimation of Chinese Beef Simmental Cattle Using High-density SNP Panels

Zhu, M.,Zhu, B.,Wang, Y.H.,Wu, Y.,Xu, L.,Guo, L.P.,Yuan, Z.R.,Zhang, L.P.,Gao, X.,Gao, H.J.,Xu, S.Z.,Li, J.Y. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.6

Linkage disequilibrium (LD) plays an important role in genomic selection and mapping quantitative trait loci (QTL). In this study, the pattern of LD and effective population size ($N_e$) were investigated in Chinese beef Simmental cattle. A total of 640 bulls were genotyped with IlluminaBovinSNP50BeadChip and IlluminaBovinHDBeadChip. We estimated LD for each autosomal chromosome at the distance between two random SNPs of <0 to 25 kb, 25 to 50 kb, 50 to 100 kb, 100 to 500 kb, 0.5 to 1 Mb, 1 to 5 Mb and 5 to 10 Mb. The mean values of $r^2$ were 0.30, 0.16 and 0.08, when the separation between SNPs ranged from 0 to 25 kb to 50 to 100 kb and then to 0.5 to 1 Mb, respectively. The LD estimates decreased as the distance increased in SNP pairs, and increased with the increase of minor allelic frequency (MAF) and with the decrease of sample sizes. Estimates of effective population size for Chinese beef Simmental cattle decreased in the past generations and $N_e$ was 73 at five generations ago.

Inference on a structural break in trend with mildly integrated errors

Zhu Xu,Pang Tianxiao 한국통계학회 2022 Journal of the Korean Statistical Society Vol.51 No.1

In this paper, we study a regression model with a break in trend regressor, in which the model errors are assumed to be mildly integrated. To be precise, we suppose the model errors are generated by an AR(1) process with the autoregressive coefficient ρT=1+c/kT, where T is the sample size, c is a negative constant, and {kT,T∈N} is a sequence of positive constants diverging to infinity such that kT=o(T). We estimate the break date/break fraction and other parameters in the model using the least squares method. The asymptotic properties, including the consistency, rates of convergence as well as the limiting distributions, of the estimates are examined. The results derived in this paper bridge the findings in Perron and Zhu (Journal of Econometrics 129:65–119, 2005) who estimated the break date/break fraction in trend regressor under I(0) and I(1) model errors. We also show that the phase transition for the estimation error of the least squares estimate of the break date occurs when kT has the same order of magnitude as T1/2. Monte Carlo simulations and an empirical study are given to illustrate the finite-sample performance of estimates.

Content-driven Joint Allocation of Communication and Computing Resources in Vehicular Networks

Xu Zhu,Fangfang Liu,Zhimin Zeng,Caili Guo,Jiujiu Chen 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.2

With the rapid growth of computer vision applications, a large amount of video data in the Internet of Vehicles scenario are used for content analysis. Tasks based on video content understanding are usually accompanied by huge amount of calculation, which put great pressure on traditional wireless communication resource and Mobile Edge Computing (MEC) server computing resource. Furthermore, existing resource allocation schemes based on Quality of Service (QoS) or Quality of Experience (QoE) may not be the best choice for the purpose of video content understanding. In this paper, we propose a joint resource allocation scheme based on Quality of Content (QoC) to maximize the accuracy of video content understanding. Due to the real-time nature of resource allocation and the variability of the environment in autonomous driving scenarios, we design a Multi-agent Distributed Q-Learning algorithm to solve such multi-constrained nonlinear programming problems. Finally, the simulation results show that our proposed QoC-based joint resource allocation scheme has better video content understanding performance.

Fine Mapping of Pa-6 Gene for Purple Apiculus in Rice

Xu Liu,Xu Sun,Wenying Wang,Hanfeng Ding,Wei Liu,Guangxian Li,Mingsong Jiang,Changxiang Zhu,Fangyin Yao 한국식물학회 2012 Journal of Plant Biology Vol.55 No.3

Purple apiculus is one of the important agronomic traits of rice. Single-segment substitution line (SSSL) W23-07-6-02-14 in the genetic background of an elite rice variety Huajingxian74 (HJX74) with the substituted interval of RM225-RM217-RM253 on the chromosome 6 was found to have purple apiculus (Pa). To map the gene governing Pa,W23-07-6-02-14 was crossed with the recipient HJX74 to develop an F2 secondary segregation population. The ratio of purple apiculus to green apiculus showed a good fit to 3:1 ratio,indicating that Pa was controlled by a major dominant gene. The gene locus for Pa was tentatively designated as Pa-6. Using 430 individuals from the F2 segregation population, the Pa-6 locus was mapped between two SSR markers RM19556and RM19561 with genetic distances of 0.2 and 0.3 cM,respectively. For fine mapping of the Pa-6 gene, a large F2:3segregation population of 3890 individuals was developed from F2 heterzygous plants in the RM19556-RM19561 region. Recombinant analyses further mapped the Pa-6 gene locus to an interval of 41.7-kb bounded L02 and RM19561. Sequence analysis of this 41.7-kb region revealed that it contains eleven open reading frames (ORFs), of which, ORF5 is classified as the one that is associated with the C (chromogen for anthocyanin) gene, it was presumed to be the candidate gene for Pa. This result provided a foundation of map-based cloning and function analysis of the Pa-6 gene.