Effect of Different Cooling Rates in High Rheological Rate Forming Process on Mechanical Properties of Zr57Cu20Al10Ni8Ag5 Bulk Metallic Glass

Xiao‑Bo Mei,Bao‑Chuan Liu,Wei Jiang,Quan Xu,Qi‑Dong Zhang,Yu‑Bai Ma,Fang‑Qiu Zu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.9

The influence of cooling rates on the mechanical properties of a Zr-based bulk metallic glass prepared with high rheologicalrate forming (HRRF) was investigated and compared with traditional suction cast methods. Amorphous samples of Zr57Cu-20Ni8Al10Ag5 were prepared in copper molds with different sizes in order to obtain different cooling rates for both HRRFand traditional cast methods. These specimens were subjected to compression experiments, including microhardness testing,X-ray diffraction testing and differential scanning calorimetry analysis. The results indicate that the plasticity of the samplesformed by HRRF are higher than that of the as-cast ones at the same cooling rates, while the microhardness manifests theopposite principle. As the cooling rate increases further, the difference in plasticity further increases between two methods,indicating that the plasticity of metallic glasses is more sensitive to cooling rates during the HRRF process. At the core ofthis phenomenon is the fact that HRRF methods can introduce more free volume into glasses than traditional cast methodswith an elevated cooling rate are able to.

Elevated FBXL6 expression in hepatocytes activates VRK2-transketolase-ROS-mTOR-mediated immune evasion and liver cancer metastasis in mice

Zhang Jie,Lin Xiao-Tong,Yu Hong-Qiang,Fang Lei,Wu Di,Luo Yuan-Deng,Zhang Yu-Jun,Xie Chuan-Ming 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Metastatic hepatocellular carcinoma (HCC) is the most lethal malignancy and lacks effective treatment. FBXL6 is overexpressed in human hepatocellular carcinoma (HCC), but whether this change drives liver tumorigenesis and lung metastasis in vivo remains unknown. In this study, we aimed to identify FBXL6 (F-Box and Leucine Rich Repeat Protein 6) as a key driver of HCC metastasis and to provide a new paradigm for HCC therapy. We found that elevated FBXL6 expression in hepatocytes drove HCC lung metastasis and was a much stronger driver than Kras mutation (KrasG12D/+;Alb-Cre), p53 haploinsufficiency (p53+/-) or Tsc1 loss (Tsc1fl/fl;Alb-Cre). Mechanistically, VRK2 promoted Thr287 phosphorylation of TKT and then recruited FBXL6 to promote TKT ubiquitination and activation. Activated TKT further increased PD-L1 and VRK2 expression via the ROS-mTOR axis, leading to immune evasion and HCC metastasis. Targeting or knockdown of TKT significantly blocked FBXL6-driven immune evasion and HCC metastasis in vitro and in vivo. Notably, the level of active TKT (p-Thr287 TKT) was increased and was positively correlated with the FBXL6 and VRK2 expression levels in HCC patients. Our work provides novel mechanistic insights into FBXL6-driven HCC metastasis and suggests that targeting the TKT-ROS-mTOR-PD-L1/VRK2 axis is a new paradigm for treating patients with metastatic HCC with high FBXL6 expression.

An Updated Meta-analysis Between the Association of XRCC1 Arg399Gln Polymorphism and Hepatocellular Carcinoma Risk

Zhang, Xiao-Lian,Lu, Yu,Yang, Shi,Peng, Qi-Liu,Wang, Jian,Xie, Li,Deng, Yan,He, Yu,Li, Tai-Jie,Qin, Xue,Li, Shan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: Various studies have evaluated the relationship between X-ray repair cross-complementing group 1 (XRCC1) Arg399Gln polymorphism and hepatocellular carcinoma (HCC) risk, but the conclusions have been inconsistent and underpowered. The purpose of this updated meta-analysis was to examine whether XRCC1 Arg399Gln polymorphism confers susceptibility to HCC. Methods: Eligible studies extracted from PubMed, Embase, Cochrane Library, VIP (chinese) and CNKI (chinese) up to November 2013 were included in the study. Pooled odds ratio (OR) together with their 95% confidence interval (CI) were estimated to evaluate XRCC1 Arg399Gln polymorphism and HCC risk. Results: Finally, 21 studies with 4,170 cases and 5,030 controls were involved in our meta-analysis. The results demonstrated that there was significant association between Arg399Gln polymorphism and HCC risk under two contrast models in overall populations (AG vs GG: OR=1.265, 95%CI=1.036-1.545, p=0.021; AA+AG vs GG: OR=1.240, 95%CI=1.021-1.506, p=0.030). In subgroup analyses, significant association was found in Asians (A vs G: OR=1.175, 95%CI=1.013-1.362, p=0.033; AG vs GG: OR=1.317, 95%CI=1.070-1.622, p=0.009; AA+AG vs GG: OR=1.289, 95%CI=1.055-1.575, p=0.013) and Caucasians (A vs G: OR=0.591, 95%CI=0.361-0.966, p=0.036; AA+AG vs GG: OR=0.468, 95%CI=0.234-0.934, p=0.031). Conclusions: The results suggest that XRCC1 Arg399Gln polymorphism may increase HCC risk especially among Asians. However, XRCC1 Arg399Gln polymorphism might act as a protective role against HCC among Caucasians.

Numerical optimization of transmission bremsstrahlung target for intense pulsed electron beam

Xiao Yu,Jie Shen,Shijian Zhang,Jie Zhang,Nan Zhang,Ivan Sergeevich Egorov,Sha Yan,Chang Tan,Gennady Efimovich Remnev,Xiaoyun Le 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.2

The optimization of a transmission type bremsstrahlung conversion target was carried out with MonteCarlo code FLUKA for intense pulsed electron beams with electron energy of several hundred keV formaximum photon fluence. The photon emission intensity from electrons with energy ranging from300 keV to 1 MeV on tungsten, tantalum and molybdenum targets was calculated with varied targetthicknesses. The research revealed that higher target material element number and electron energy leadsto increased photon fluence. For a certain target material, the target thickness with maximum photonemission fluence exhibits a linear relationship with the electron energy. With certain electron energy andtarget material, the thickness of the target plays a dominant role in increasing the transmission photonintensity, with small target thickness the photon flux is largely restricted by low energy loss of electronsfor photon generation while thick targets may impose extra absorption for the generated photons. Thespatial distribution of bremsstrahlung photon density was analyzed and the optimal target thicknessesfor maximum bremsstrahlung photon fluence were derived versus electron energy on three targetmaterials for a quick determination of optimal target design

The catalytic core of DEMETER guides active DNA demethylation in <i>Arabidopsis</i>

Zhang, Changqing,Hung, Yu-Hung,Rim, Hyun Jung,Zhang, Dapeng,Frost, Jennifer M.,Shin, Hosub,Jang, Hosung,Liu, Fang,Xiao, Wenyan,Iyer, Lakshminarayan M.,Aravind, L.,Zhang, Xiang-Qian,Fischer, Robert L. National Academy of Sciences 2019 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.116 No.35

<P><B>Significance</B></P><P>Flowering plants reproduce via a unique double-fertilization event, producing the zygote and the nutritive endosperm. The genome of the central cell, the precursor of the endosperm, undergoes extensive demethylation prior to fertilization. This epigenetic reconfiguration, directed by the DEMETER (DME) glycosylase at thousands of loci in <I>Arabidopsis</I>, differentiates the epigenetic landscapes of parental genomes and establishes parent of origin-specific expression of many imprinted genes in endosperm essential for seed development. However, how DME is targeted to various locations remains unknown. Here we show that the multidomain DME is organized into 2 functional regions: the C-terminal region, which guides localization and catalysis, and the N-terminal region, which likely recruits chromatin remodelers to facilitate demethylation within heterochromatin.</P><P>The <I>Arabidopsis</I> DEMETER (DME) DNA glycosylase demethylates the maternal genome in the central cell prior to fertilization and is essential for seed viability. DME preferentially targets small transposons that flank coding genes, influencing their expression and initiating plant gene imprinting. DME also targets intergenic and heterochromatic regions, but how it is recruited to these differing chromatin landscapes is unknown. The C-terminal half of DME consists of 3 conserved regions required for catalysis in vitro. We show that this catalytic core guides active demethylation at endogenous targets, rescuing <I>dme</I> developmental and genomic hypermethylation phenotypes. However, without the N terminus, heterochromatin demethylation is significantly impeded, and abundant CG-methylated genic sequences are ectopically demethylated. Comparative analysis revealed that the conserved DME N-terminal domains are present only in flowering plants, whereas the domain architecture of DME-like proteins in nonvascular plants mainly resembles the catalytic core, suggesting that it might represent the ancestral form of the 5mC DNA glycosylase found in plant lineages. We propose a bipartite model for DME protein action and suggest that the DME N terminus was acquired late during land plant evolution to improve specificity and facilitate demethylation at heterochromatin targets.</P>

American ginseng attenuates azoxymethane/dextran sodium sulfate-induced colon carcinogenesis in mice

Yu, Chunhao,Wen, Xiao-Dong,Zhang, Zhiyu,Zhang, Chun-Feng,Wu, Xiao-Hui,Martin, Adiba,Du, Wei,He, Tong-Chuan,Wang, Chong-Zhi,Yuan, Chun-Su The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.1

Background: Colorectal cancer is a leading cause of cancer-related death, and inflammatory bowel disease is a risk factor for this malignancy. We previously reported colon cancer chemoprevention potential using American ginseng (AG) in a xenograft mice model. However, the nude mouse model is not a gut-specific colon carcinogenesis animal model. Methods: In this study, an experimental colitis and colitis-associated colorectal carcinogenesis mouse model, chemically induced by azoxymethane/dextran sodium sulfate (DSS) was established and the effects of oral AG were evaluated. The contents of representative ginseng saponins in the extract were determined. Results: AG significantly reduced experimental colitis measured by the disease activity index scores. This suppression of the experimental colitis was not only evident during DSS treatment, but also very obvious after the cessation of DSS, suggesting that the ginseng significantly promoted recovery from the colitis. Consistent with the anti-inflammation data, we showed that ginseng very significantly attenuated azoxymethane/DSS-induced colon carcinogenesis by reducing the colon tumor number and tumor load. The ginseng also effectively suppressed DSS-induced proinflammatory cytokines activation using an enzyme-linked immunosorbent assay array, in which 12 proinflammatory cytokine levels were assessed, and this effect was supported subsequently by real-time polymerase chain reaction data. Conclusion: AG, as a candidate of botanical-based colon cancer chemoprevention, should be further investigated for its potential clinical utility.

Reliable control of magnetic vortex chirality in asymmetrically optimized magnetic nanodisk

Zhang Huanhuan,Yu Hai,Zhang Xue-Feng,Yang Xiao-Xue,Shim Je-Ho,Ma Xiao-Ping,Piao Hong-Guang 한국물리학회 2022 Current Applied Physics Vol.43 No.-

Magnetic vortex has attracted attention in the field of information storage because their topological spin structures with chiral bistable states. If the vortex core polarity and vortex circulation sense can be controlled simultaneously in a nanodisk, which will be more beneficial to realize the multi-bit ultrahigh density storage. In this paper, a reliable control scheme for magnetic vortex chirality is proposed by optimizing the structure of Pac- Man-like nanodisk. The results show that the polarity and circulation of the vortex can be controlled simultaneously by changing the direction of the global magnetic field, and even the chiral states of the vortex can be determined by detecting the stray field distribution on the surface of the nanodisk. The optimized Pac-Man-like nanodisk provide an experimental method for the control and detection of magnetic vortex chirality, which will be beneficial to the realization of multi-bit magnetic storage or magnetic logic technology in the future.

A Ka Band Coupled Line Directional Coupler Based on the CPW Technology

Xiao-Yu Zhang,Jong-Chul Lee 한국통신학회 2022 한국통신학회 학술대회논문집 Vol.2022 No.11

A Dual-Band Branch-Line Coupler with Ultra-Wideband Harmonic Suppression

Xiao-Yu Zhang,Jong-Chul Lee 한국전자파학회JEES 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.1

Effects of IBA on rooting ability of Cinnamomum bodinieri citral type micro-shoots from transcriptomics analysis

Xiao Zufei,Jin Zhinong,Zhang Beihong,Li Feng,Yu Faxin,Zhang Haiyan,Lü Xiongwei,Zhang Jie 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.4

Cinnamomum bodinieri is a useful plant that could be improved by increasing its cultivation rate. To explore the optimal concentration of exogenously applied IBA for root formation and development in the C. bodinieri citral type, micro-shoots and the fresh tissues of their bases were subjected to morphological and transcriptome analyses, respectively. When plantedQuery on a rooting medium (1/2 MS) with 1.5 mg/L IBA for 25 days, the rooting rates and root numbers were significantly higher than those obtained with 0, 0.5, 1.0, or 2.0 mg/L IBA treatment. Transcriptome analyses conducted 0 day, 7 days, 11 days, and 14 days after planting in the optimal rooting medium demonstrated that the IBA modified the plant’s carbohydrate metabolism and auxin signaling pathway. The root-specific expressions of TIR1, GH3, and SAUR were up-expressed while AUX/IAA was repressed, which contributed to the formation of lateral root initiation sites and root cell elongation. At the same time, d-glucose synthesis increased and the accumulation of starch decreased as more carbohydrates were used to form and develop roots instead of being used for the rapid cell division required for shoot growth. This study identified the optimal rooting medium for the C. bodinieri citral type and determined the molecular mechanisms involved in the regulation of exogenously applied IBA during root formation and development at the transcriptional level.